* [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer
@ 2020-07-22 5:55 Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 1/4] drm/i915/perf: Ensure observation logic is not clock gated Umesh Nerlige Ramappa
` (5 more replies)
0 siblings, 6 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-22 5:55 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
This cover letter is included to trigger "Test-with" an IGT patch.
Tests - https://patchwork.freedesktop.org/series/79745/
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Test-with: 20200722053805.57139-1-umesh.nerlige.ramappa@intel.com
Piotr Maciejewski (4):
drm/i915/perf: Ensure observation logic is not clock gated
drm/i915/perf: Whitelist OA report trigger registers
drm/i915/perf: Whitelist OA counter and buffer registers
drm/i915/perf: Map OA buffer to user space for gen12 performance query
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/gt/intel_workarounds.c | 60 +++++
.../gpu/drm/i915/gt/selftest_workarounds.c | 38 ++-
drivers/gpu/drm/i915/i915_perf.c | 239 +++++++++++++++++-
drivers/gpu/drm/i915/i915_perf_types.h | 17 ++
drivers/gpu/drm/i915/i915_reg.h | 12 +
include/uapi/drm/i915_drm.h | 32 +++
8 files changed, 396 insertions(+), 6 deletions(-)
--
2.20.1
_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 1/4] drm/i915/perf: Ensure observation logic is not clock gated
2020-07-22 5:55 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-07-22 5:55 ` Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 2/4] drm/i915/perf: Whitelist OA report trigger registers Umesh Nerlige Ramappa
` (4 subsequent siblings)
5 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-22 5:55 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
From: Piotr Maciejewski <piotr.maciejewski@intel.com>
A clock gating switch can control if the performance monitoring and
observation logic is enaled or not. Ensure that we enable the clocks.
v2: Separate code from other patches (Lionel)
v3: Reset PMON enable when disabling perf to save power (Lionel)
Fixes: 00a7f0d7155c ("drm/i915/tgl: Add perf support on TGL")
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
---
drivers/gpu/drm/i915/i915_perf.c | 13 +++++++++++++
drivers/gpu/drm/i915/i915_reg.h | 2 ++
2 files changed, 15 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index c6f6370283cf..fe408c327d3c 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -2493,6 +2493,14 @@ gen12_enable_metric_set(struct i915_perf_stream *stream,
(period_exponent << GEN12_OAG_OAGLBCTXCTRL_TIMER_PERIOD_SHIFT))
: 0);
+ /*
+ * Initialize Super Queue Internal Cnt Register
+ * Set PMON Enable in order to collect valid metrics.
+ */
+ intel_uncore_write(uncore, GEN12_SQCNT1,
+ intel_uncore_read(uncore, GEN12_SQCNT1) |
+ GEN12_SQCNT1_PMON_ENABLE);
+
/*
* Update all contexts prior writing the mux configurations as we need
* to make sure all slices/subslices are ON before writing to NOA
@@ -2552,6 +2560,11 @@ static void gen12_disable_metric_set(struct i915_perf_stream *stream)
/* Make sure we disable noa to save power. */
intel_uncore_rmw(uncore, RPM_CONFIG1, GEN10_GT_NOA_ENABLE, 0);
+
+ /* Reset PMON Enable to save power. */
+ intel_uncore_write(uncore, GEN12_SQCNT1,
+ intel_uncore_read(uncore, GEN12_SQCNT1) &
+ ~GEN12_SQCNT1_PMON_ENABLE);
}
static void gen7_oa_enable(struct i915_perf_stream *stream)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index a0d31f3bf634..9cc3e312b6b7 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -696,6 +696,8 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
#define OABUFFER_SIZE_16M (7 << 3)
#define GEN12_OA_TLB_INV_CR _MMIO(0xceec)
+#define GEN12_SQCNT1 _MMIO(0x8718)
+#define GEN12_SQCNT1_PMON_ENABLE (1 << 30)
/* Gen12 OAR unit */
#define GEN12_OAR_OACONTROL _MMIO(0x2960)
--
2.20.1
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 2/4] drm/i915/perf: Whitelist OA report trigger registers
2020-07-22 5:55 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 1/4] drm/i915/perf: Ensure observation logic is not clock gated Umesh Nerlige Ramappa
@ 2020-07-22 5:55 ` Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 3/4] drm/i915/perf: Whitelist OA counter and buffer registers Umesh Nerlige Ramappa
` (3 subsequent siblings)
5 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-22 5:55 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
From: Piotr Maciejewski <piotr.maciejewski@intel.com>
OA reports can be triggered into the OA buffer by writing into the
OAREPORTTRIG registers. Whitelist the registers to allow user to trigger
reports.
v2:
- Move related change to this patch (Lionel)
- Bump up perf revision (Lionel)
v3: Pardon whitelisted registers for selftest (Umesh)
v4: Document supported gens for the feature (Lionel)
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
---
drivers/gpu/drm/i915/gt/intel_workarounds.c | 26 +++++++++++++++++++
.../gpu/drm/i915/gt/selftest_workarounds.c | 8 ++++++
drivers/gpu/drm/i915/i915_perf.c | 11 +++++---
3 files changed, 42 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index cef1c122696f..a72ebfd115e5 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -1387,6 +1387,20 @@ whitelist_reg(struct i915_wa_list *wal, i915_reg_t reg)
whitelist_reg_ext(wal, reg, RING_FORCE_TO_NONPRIV_ACCESS_RW);
}
+static void gen9_whitelist_build_performance_counters(struct i915_wa_list *w)
+{
+ /* OA buffer trigger report 2/6 used by performance query */
+ whitelist_reg(w, OAREPORTTRIG2);
+ whitelist_reg(w, OAREPORTTRIG6);
+}
+
+static void gen12_whitelist_build_performance_counters(struct i915_wa_list *w)
+{
+ /* OA buffer trigger report 2/6 used by performance query */
+ whitelist_reg(w, GEN12_OAG_OAREPORTTRIG2);
+ whitelist_reg(w, GEN12_OAG_OAREPORTTRIG6);
+}
+
static void gen9_whitelist_build(struct i915_wa_list *w)
{
/* WaVFEStateAfterPipeControlwithMediaStateClear:skl,bxt,glk,cfl */
@@ -1400,6 +1414,9 @@ static void gen9_whitelist_build(struct i915_wa_list *w)
/* WaSendPushConstantsFromMMIO:skl,bxt */
whitelist_reg(w, COMMON_SLICE_CHICKEN2);
+
+ /* Performance counters support */
+ gen9_whitelist_build_performance_counters(w);
}
static void skl_whitelist_build(struct intel_engine_cs *engine)
@@ -1493,6 +1510,9 @@ static void cnl_whitelist_build(struct intel_engine_cs *engine)
/* WaEnablePreemptionGranularityControlByUMD:cnl */
whitelist_reg(w, GEN8_CS_CHICKEN1);
+
+ /* Performance counters support */
+ gen9_whitelist_build_performance_counters(w);
}
static void icl_whitelist_build(struct intel_engine_cs *engine)
@@ -1522,6 +1542,9 @@ static void icl_whitelist_build(struct intel_engine_cs *engine)
whitelist_reg_ext(w, PS_INVOCATION_COUNT,
RING_FORCE_TO_NONPRIV_ACCESS_RD |
RING_FORCE_TO_NONPRIV_RANGE_4);
+
+ /* Performance counters support */
+ gen9_whitelist_build_performance_counters(w);
break;
case VIDEO_DECODE_CLASS:
@@ -1572,6 +1595,9 @@ static void tgl_whitelist_build(struct intel_engine_cs *engine)
/* Wa_1806527549:tgl */
whitelist_reg(w, HIZ_CHICKEN);
+
+ /* Performance counters support */
+ gen12_whitelist_build_performance_counters(w);
break;
default:
whitelist_reg_ext(w,
diff --git a/drivers/gpu/drm/i915/gt/selftest_workarounds.c b/drivers/gpu/drm/i915/gt/selftest_workarounds.c
index febc9e6692ba..3b1d3dbcd477 100644
--- a/drivers/gpu/drm/i915/gt/selftest_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/selftest_workarounds.c
@@ -934,6 +934,10 @@ static bool pardon_reg(struct drm_i915_private *i915, i915_reg_t reg)
static const struct regmask pardon[] = {
{ GEN9_CTX_PREEMPT_REG, INTEL_GEN_MASK(9, 9) },
{ GEN8_L3SQCREG4, INTEL_GEN_MASK(9, 9) },
+ { OAREPORTTRIG2, INTEL_GEN_MASK(8, 11) },
+ { OAREPORTTRIG6, INTEL_GEN_MASK(8, 11) },
+ { GEN12_OAG_OAREPORTTRIG2, INTEL_GEN_MASK(12, 12) },
+ { GEN12_OAG_OAREPORTTRIG6, INTEL_GEN_MASK(12, 12) },
};
return find_reg(i915, reg, pardon, ARRAY_SIZE(pardon));
@@ -956,6 +960,10 @@ static bool writeonly_reg(struct drm_i915_private *i915, i915_reg_t reg)
/* Some registers do not seem to behave and our writes unreadable */
static const struct regmask wo[] = {
{ GEN9_SLICE_COMMON_ECO_CHICKEN1, INTEL_GEN_MASK(9, 9) },
+ { OAREPORTTRIG2, INTEL_GEN_MASK(8, 11) },
+ { OAREPORTTRIG6, INTEL_GEN_MASK(8, 11) },
+ { GEN12_OAG_OAREPORTTRIG2, INTEL_GEN_MASK(12, 12) },
+ { GEN12_OAG_OAREPORTTRIG6, INTEL_GEN_MASK(12, 12) },
};
return find_reg(i915, reg, wo, ARRAY_SIZE(wo));
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index fe408c327d3c..30f6aeb819aa 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -1448,7 +1448,8 @@ static void gen8_init_oa_buffer(struct i915_perf_stream *stream)
* bit."
*/
intel_uncore_write(uncore, GEN8_OABUFFER, gtt_offset |
- OABUFFER_SIZE_16M | GEN8_OABUFFER_MEM_SELECT_GGTT);
+ OABUFFER_SIZE_16M | GEN8_OABUFFER_MEM_SELECT_GGTT |
+ GEN7_OABUFFER_EDGE_TRIGGER);
intel_uncore_write(uncore, GEN8_OATAILPTR, gtt_offset & GEN8_OATAILPTR_MASK);
/* Mark that we need updated tail pointers to read from... */
@@ -1501,7 +1502,8 @@ static void gen12_init_oa_buffer(struct i915_perf_stream *stream)
* bit."
*/
intel_uncore_write(uncore, GEN12_OAG_OABUFFER, gtt_offset |
- OABUFFER_SIZE_16M | GEN8_OABUFFER_MEM_SELECT_GGTT);
+ OABUFFER_SIZE_16M | GEN8_OABUFFER_MEM_SELECT_GGTT |
+ GEN7_OABUFFER_EDGE_TRIGGER);
intel_uncore_write(uncore, GEN12_OAG_OATAILPTR,
gtt_offset & GEN12_OAG_OATAILPTR_MASK);
@@ -4445,8 +4447,11 @@ int i915_perf_ioctl_version(void)
*
* 5: Add DRM_I915_PERF_PROP_POLL_OA_PERIOD parameter that controls the
* interval for the hrtimer used to check for OA data.
+ *
+ * 6: Whitelist OATRIGGER registers to allow user to trigger reports
+ * into the OA buffer. This applies only to gen8+.
*/
- return 5;
+ return 6;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
--
2.20.1
_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 3/4] drm/i915/perf: Whitelist OA counter and buffer registers
2020-07-22 5:55 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 1/4] drm/i915/perf: Ensure observation logic is not clock gated Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 2/4] drm/i915/perf: Whitelist OA report trigger registers Umesh Nerlige Ramappa
@ 2020-07-22 5:55 ` Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
` (2 subsequent siblings)
5 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-22 5:55 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
From: Piotr Maciejewski <piotr.maciejewski@intel.com>
It is useful to have markers in the OA reports to identify triggered
reports. Whitelist some OA counters that can be used as markers.
A triggered report can be found faster if we can sample the HW tail and
head registers when the report was triggered. Whitelist OA buffer
specific registers.
v2:
- Bump up the perf revision (Lionel)
- Use indexing for counters (Lionel)
- Fix selftest for oa ticking register (Umesh)
v3: Pardon whitelisted registers for selftest (Umesh)
v4:
- Document whitelisted registers (Lionel)
- Fix live isolated whitelist for OA regs (Umesh)
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
---
drivers/gpu/drm/i915/gt/intel_workarounds.c | 34 +++++++++++++++++++
.../gpu/drm/i915/gt/selftest_workarounds.c | 30 +++++++++++++++-
drivers/gpu/drm/i915/i915_perf.c | 8 ++++-
drivers/gpu/drm/i915/i915_reg.h | 10 ++++++
4 files changed, 80 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index a72ebfd115e5..c950d07beec3 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -1392,6 +1392,23 @@ static void gen9_whitelist_build_performance_counters(struct i915_wa_list *w)
/* OA buffer trigger report 2/6 used by performance query */
whitelist_reg(w, OAREPORTTRIG2);
whitelist_reg(w, OAREPORTTRIG6);
+
+ /* Performance counters A18-20 used by tbs marker query */
+ whitelist_reg_ext(w, OA_PERF_COUNTER_A(18),
+ RING_FORCE_TO_NONPRIV_ACCESS_RW |
+ RING_FORCE_TO_NONPRIV_RANGE_4);
+
+ whitelist_reg(w, OA_PERF_COUNTER_A(20));
+ whitelist_reg(w, OA_PERF_COUNTER_A_UPPER(20));
+
+ /* Read access to gpu ticks */
+ whitelist_reg_ext(w, GEN8_GPU_TICKS,
+ RING_FORCE_TO_NONPRIV_ACCESS_RD);
+
+ /* Read access to: oa status, head, tail, buffer settings */
+ whitelist_reg_ext(w, GEN8_OASTATUS,
+ RING_FORCE_TO_NONPRIV_ACCESS_RD |
+ RING_FORCE_TO_NONPRIV_RANGE_4);
}
static void gen12_whitelist_build_performance_counters(struct i915_wa_list *w)
@@ -1399,6 +1416,23 @@ static void gen12_whitelist_build_performance_counters(struct i915_wa_list *w)
/* OA buffer trigger report 2/6 used by performance query */
whitelist_reg(w, GEN12_OAG_OAREPORTTRIG2);
whitelist_reg(w, GEN12_OAG_OAREPORTTRIG6);
+
+ /* Performance counters A18-20 used by tbs marker query */
+ whitelist_reg_ext(w, GEN12_OAG_PERF_COUNTER_A(18),
+ RING_FORCE_TO_NONPRIV_ACCESS_RW |
+ RING_FORCE_TO_NONPRIV_RANGE_4);
+
+ whitelist_reg(w, GEN12_OAG_PERF_COUNTER_A(20));
+ whitelist_reg(w, GEN12_OAG_PERF_COUNTER_A_UPPER(20));
+
+ /* Read access to gpu ticks */
+ whitelist_reg_ext(w, GEN12_OAG_GPU_TICKS,
+ RING_FORCE_TO_NONPRIV_ACCESS_RD);
+
+ /* Read access to: oa status, head, tail, buffer settings */
+ whitelist_reg_ext(w, GEN12_OAG_OASTATUS,
+ RING_FORCE_TO_NONPRIV_ACCESS_RD |
+ RING_FORCE_TO_NONPRIV_RANGE_4);
}
static void gen9_whitelist_build(struct i915_wa_list *w)
diff --git a/drivers/gpu/drm/i915/gt/selftest_workarounds.c b/drivers/gpu/drm/i915/gt/selftest_workarounds.c
index 3b1d3dbcd477..7c2c2be8d212 100644
--- a/drivers/gpu/drm/i915/gt/selftest_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/selftest_workarounds.c
@@ -431,6 +431,19 @@ static bool timestamp(const struct intel_engine_cs *engine, u32 reg)
}
}
+static bool oa_gpu_ticks(u32 reg)
+{
+ reg = reg & ~RING_FORCE_TO_NONPRIV_ACCESS_MASK;
+ switch (reg) {
+ case 0x2910:
+ case 0xda90:
+ return true;
+
+ default:
+ return false;
+ }
+}
+
static bool ro_register(u32 reg)
{
if ((reg & RING_FORCE_TO_NONPRIV_ACCESS_MASK) ==
@@ -511,7 +524,7 @@ static int check_dirty_whitelist(struct intel_context *ce)
if (wo_register(engine, reg))
continue;
- if (timestamp(engine, reg))
+ if (timestamp(engine, reg) || oa_gpu_ticks(reg))
continue; /* timestamps are expected to autoincrement */
ro_reg = ro_register(reg);
@@ -918,6 +931,9 @@ static bool find_reg(struct drm_i915_private *i915,
{
u32 offset = i915_mmio_reg_offset(reg);
+ /* Clear non priv flags */
+ offset &= RING_FORCE_TO_NONPRIV_ADDRESS_MASK;
+
while (count--) {
if (INTEL_INFO(i915)->gen_mask & tbl->gen_mask &&
i915_mmio_reg_offset(tbl->reg) == offset)
@@ -938,6 +954,12 @@ static bool pardon_reg(struct drm_i915_private *i915, i915_reg_t reg)
{ OAREPORTTRIG6, INTEL_GEN_MASK(8, 11) },
{ GEN12_OAG_OAREPORTTRIG2, INTEL_GEN_MASK(12, 12) },
{ GEN12_OAG_OAREPORTTRIG6, INTEL_GEN_MASK(12, 12) },
+ { OA_PERF_COUNTER_A(18), INTEL_GEN_MASK(8, 11) },
+ { OA_PERF_COUNTER_A(20), INTEL_GEN_MASK(8, 11) },
+ { OA_PERF_COUNTER_A_UPPER(20), INTEL_GEN_MASK(8, 11) },
+ { GEN12_OAG_PERF_COUNTER_A(18), INTEL_GEN_MASK(12, 12) },
+ { GEN12_OAG_PERF_COUNTER_A(20), INTEL_GEN_MASK(12, 12) },
+ { GEN12_OAG_PERF_COUNTER_A_UPPER(20), INTEL_GEN_MASK(12, 12) },
};
return find_reg(i915, reg, pardon, ARRAY_SIZE(pardon));
@@ -964,6 +986,12 @@ static bool writeonly_reg(struct drm_i915_private *i915, i915_reg_t reg)
{ OAREPORTTRIG6, INTEL_GEN_MASK(8, 11) },
{ GEN12_OAG_OAREPORTTRIG2, INTEL_GEN_MASK(12, 12) },
{ GEN12_OAG_OAREPORTTRIG6, INTEL_GEN_MASK(12, 12) },
+ { OA_PERF_COUNTER_A(18), INTEL_GEN_MASK(8, 11) },
+ { OA_PERF_COUNTER_A(20), INTEL_GEN_MASK(8, 11) },
+ { OA_PERF_COUNTER_A_UPPER(20), INTEL_GEN_MASK(8, 11) },
+ { GEN12_OAG_PERF_COUNTER_A(18), INTEL_GEN_MASK(12, 12) },
+ { GEN12_OAG_PERF_COUNTER_A(20), INTEL_GEN_MASK(12, 12) },
+ { GEN12_OAG_PERF_COUNTER_A_UPPER(20), INTEL_GEN_MASK(12, 12) },
};
return find_reg(i915, reg, wo, ARRAY_SIZE(wo));
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 30f6aeb819aa..2f23aad12c60 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -4450,8 +4450,14 @@ int i915_perf_ioctl_version(void)
*
* 6: Whitelist OATRIGGER registers to allow user to trigger reports
* into the OA buffer. This applies only to gen8+.
+ *
+ * 7: Whitelist below OA registers for user to identify the location of
+ * triggered reports in the OA buffer. This applies only to gen8+.
+ *
+ * - OA buffer head/tail/status/buffer registers for read only
+ * - OA counters A18, A19, A20 for read/write
*/
- return 6;
+ return 7;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 9cc3e312b6b7..c68dc3f39e62 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -675,6 +675,7 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
#define GEN7_OASTATUS2_HEAD_MASK 0xffffffc0
#define GEN7_OASTATUS2_MEM_SELECT_GGTT (1 << 0) /* 0: PPGTT, 1: GGTT */
+#define GEN8_GPU_TICKS _MMIO(0x2910)
#define GEN8_OASTATUS _MMIO(0x2b08)
#define GEN8_OASTATUS_OVERRUN_STATUS (1 << 3)
#define GEN8_OASTATUS_COUNTER_OVERFLOW (1 << 2)
@@ -733,6 +734,7 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
#define GEN12_OAG_OA_DEBUG_DISABLE_GO_1_0_REPORTS (1 << 2)
#define GEN12_OAG_OA_DEBUG_DISABLE_CTX_SWITCH_REPORTS (1 << 1)
+#define GEN12_OAG_GPU_TICKS _MMIO(0xda90)
#define GEN12_OAG_OASTATUS _MMIO(0xdafc)
#define GEN12_OAG_OASTATUS_COUNTER_OVERFLOW (1 << 2)
#define GEN12_OAG_OASTATUS_BUFFER_OVERFLOW (1 << 1)
@@ -974,6 +976,14 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
#define OAREPORTTRIG8_NOA_SELECT_6_SHIFT 24
#define OAREPORTTRIG8_NOA_SELECT_7_SHIFT 28
+/* Performance counters registers */
+#define OA_PERF_COUNTER_A(idx) _MMIO(0x2800 + 8 * (idx))
+#define OA_PERF_COUNTER_A_UPPER(idx) _MMIO(0x2800 + 8 * (idx) + 4)
+
+/* Gen12 Performance counters registers */
+#define GEN12_OAG_PERF_COUNTER_A(idx) _MMIO(0xD980 + 8 * (idx))
+#define GEN12_OAG_PERF_COUNTER_A_UPPER(idx) _MMIO(0xD980 + 8 * (idx) + 4)
+
/* Same layout as OASTARTTRIGX */
#define GEN12_OAG_OASTARTTRIG1 _MMIO(0xd900)
#define GEN12_OAG_OASTARTTRIG2 _MMIO(0xd904)
--
2.20.1
_______________________________________________
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https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-22 5:55 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
` (2 preceding siblings ...)
2020-07-22 5:55 ` [Intel-gfx] [PATCH 3/4] drm/i915/perf: Whitelist OA counter and buffer registers Umesh Nerlige Ramappa
@ 2020-07-22 5:55 ` Umesh Nerlige Ramappa
2020-07-23 9:31 ` Lionel Landwerlin
2020-07-22 6:27 ` [Intel-gfx] ✗ Fi.CI.SPARSE: warning for Allow privileged user to map the OA buffer (rev4) Patchwork
2020-07-22 6:48 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork
5 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-22 5:55 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
From: Piotr Maciejewski <piotr.maciejewski@intel.com>
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is
mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
v4: Call kref_put on closing perf fd (Chris)
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 211 ++++++++++++++++++++++-
drivers/gpu/drm/i915/i915_perf_types.h | 17 ++
include/uapi/drm/i915_drm.h | 32 ++++
5 files changed, 261 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 2f23aad12c60..331c3f9c59e2 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -378,6 +380,24 @@ static struct ctl_table_header *sysctl_header;
static enum hrtimer_restart oa_poll_check_timer_cb(struct hrtimer *hrtimer);
+static void free_stream(struct kref *kref)
+{
+ struct i915_perf_stream *stream =
+ container_of(kref, typeof(*stream), refcount);
+
+ kfree(stream);
+}
+
+static void perf_stream_get(struct i915_perf_stream *stream)
+{
+ kref_get(&stream->refcount);
+}
+
+static void perf_stream_put(struct i915_perf_stream *stream)
+{
+ kref_put(&stream->refcount, free_stream);
+}
+
void i915_oa_config_release(struct kref *ref)
{
struct i915_oa_config *oa_config =
@@ -434,6 +454,30 @@ static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream)
return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;
}
+static u32 gen12_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+
+ return intel_uncore_read(uncore, GEN12_OAG_OAHEADPTR) &
+ GEN12_OAG_OAHEADPTR_MASK;
+}
+
+static u32 gen8_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+
+ return intel_uncore_read(uncore, GEN8_OAHEADPTR) &
+ GEN8_OAHEADPTR_MASK;
+}
+
+static u32 gen7_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+ u32 oastatus2 = intel_uncore_read(uncore, GEN7_OASTATUS2);
+
+ return oastatus2 & GEN7_OASTATUS2_HEAD_MASK;
+}
+
/**
* oa_buffer_check_unlocked - check for data and update tail ptr state
* @stream: i915 stream instance
@@ -2934,6 +2978,7 @@ static int i915_oa_stream_init(struct i915_perf_stream *stream,
stream->poll_check_timer.function = oa_poll_check_timer_cb;
init_waitqueue_head(&stream->poll_wq);
spin_lock_init(&stream->oa_buffer.ptr_lock);
+ kref_init(&stream->refcount);
return 0;
@@ -3214,6 +3259,69 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+/**
+ * i915_perf_oa_buffer_head_tail_locked - head and tail of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer head and tail filled by this function.
+ */
+static int i915_perf_oa_buffer_head_tail_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_head_tail ht;
+ void __user *output = (void __user *)arg;
+ u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (!output)
+ return -EINVAL;
+
+ memset(&ht, 0, sizeof(ht));
+
+ ht.head = stream->perf->ops.oa_hw_head_read(stream) - gtt_offset;
+ ht.tail = stream->perf->ops.oa_hw_tail_read(stream) - gtt_offset;
+
+ if (copy_to_user(output, &ht, sizeof(ht)))
+ return -EFAULT;
+
+ return 0;
+}
+
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (!output)
+ return -EINVAL;
+
+ memset(&info, 0, sizeof(info));
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3239,6 +3347,10 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL:
+ return i915_perf_oa_buffer_head_tail_locked(stream, arg);
}
return -EINVAL;
@@ -3291,7 +3403,8 @@ static void i915_perf_destroy_locked(struct i915_perf_stream *stream)
if (stream->ctx)
i915_gem_context_put(stream->ctx);
- kfree(stream);
+ WRITE_ONCE(stream->closed, true);
+ perf_stream_put(stream);
}
/**
@@ -3314,12 +3427,98 @@ static int i915_perf_release(struct inode *inode, struct file *file)
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
+ unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
+
/* Release the reference the perf stream kept on the driver. */
drm_dev_put(&perf->i915->drm);
return 0;
}
+static void vm_open_oa(struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = vma->vm_private_data;
+
+ GEM_BUG_ON(!stream);
+ perf_stream_get(stream);
+}
+
+static void vm_close_oa(struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = vma->vm_private_data;
+
+ GEM_BUG_ON(!stream);
+ perf_stream_put(stream);
+}
+
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ struct i915_perf *perf = stream->perf;
+ struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
+ int err;
+ bool closed;
+
+ mutex_lock(&perf->lock);
+ closed = READ_ONCE(stream->closed);
+ mutex_unlock(&perf->lock);
+
+ if (closed)
+ return VM_FAULT_SIGBUS;
+
+ err = i915_gem_object_pin_pages(obj);
+ if (err)
+ goto out;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ obj->mm.pages->sgl, -1);
+
+ i915_gem_object_unpin_pages(obj);
+
+out:
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .open = vm_open_oa,
+ .close = vm_close_oa,
+ .fault = vm_fault_oa,
+};
+
+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ if (vma->vm_flags & VM_WRITE)
+ return -EINVAL;
+
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC | VM_MAYSHARE);
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+ vm_open_oa(vma);
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3332,6 +3531,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4260,6 +4460,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.oa_disable = gen7_oa_disable;
perf->ops.read = gen7_oa_read;
perf->ops.oa_hw_tail_read = gen7_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen7_oa_hw_head_read;
perf->oa_formats = hsw_oa_formats;
} else if (HAS_LOGICAL_RING_CONTEXTS(i915)) {
@@ -4291,6 +4492,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen8_enable_metric_set;
perf->ops.disable_metric_set = gen8_disable_metric_set;
perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
if (IS_GEN(i915, 8)) {
perf->ctx_oactxctrl_offset = 0x120;
@@ -4318,6 +4520,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen8_enable_metric_set;
perf->ops.disable_metric_set = gen10_disable_metric_set;
perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
if (IS_GEN(i915, 10)) {
perf->ctx_oactxctrl_offset = 0x128;
@@ -4342,6 +4545,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen12_enable_metric_set;
perf->ops.disable_metric_set = gen12_disable_metric_set;
perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen12_oa_hw_head_read;
perf->ctx_flexeu0_offset = 0;
perf->ctx_oactxctrl_offset = 0x144;
@@ -4456,8 +4660,11 @@ int i915_perf_ioctl_version(void)
*
* - OA buffer head/tail/status/buffer registers for read only
* - OA counters A18, A19, A20 for read/write
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
index a36a455ae336..2efbe35c5fa9 100644
--- a/drivers/gpu/drm/i915/i915_perf_types.h
+++ b/drivers/gpu/drm/i915/i915_perf_types.h
@@ -311,6 +311,18 @@ struct i915_perf_stream {
* buffer should be checked for available data.
*/
u64 poll_oa_period;
+
+ /**
+ * @closed: Open or closed state of the stream.
+ * True if stream is closed.
+ */
+ bool closed;
+
+ /**
+ * @refcount: References to the mapped OA buffer managed by this
+ * stream.
+ */
+ struct kref refcount;
};
/**
@@ -377,6 +389,11 @@ struct i915_oa_ops {
* generations.
*/
u32 (*oa_hw_tail_read)(struct i915_perf_stream *stream);
+
+ /**
+ * @oa_hw_head_read: read the OA head pointer register
+ */
+ u32 (*oa_hw_head_read)(struct i915_perf_stream *stream);
};
struct i915_perf {
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..2042f6339182 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,38 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IO('i', 0x3)
+
+/**
+ * OA buffer size and offset.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 size;
+ __u32 offset;
+ __u64 reserved[4];
+};
+
+/**
+ * Returns current position of OA buffer head and tail.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL _IO('i', 0x4)
+
+/**
+ * OA buffer head and tail.
+ */
+struct drm_i915_perf_oa_buffer_head_tail {
+ __u32 head;
+ __u32 tail;
+ __u64 reserved[4];
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 33+ messages in thread
* [Intel-gfx] ✗ Fi.CI.SPARSE: warning for Allow privileged user to map the OA buffer (rev4)
2020-07-22 5:55 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
` (3 preceding siblings ...)
2020-07-22 5:55 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
@ 2020-07-22 6:27 ` Patchwork
2020-07-22 6:48 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork
5 siblings, 0 replies; 33+ messages in thread
From: Patchwork @ 2020-07-22 6:27 UTC (permalink / raw)
To: Umesh Nerlige Ramappa; +Cc: intel-gfx
== Series Details ==
Series: Allow privileged user to map the OA buffer (rev4)
URL : https://patchwork.freedesktop.org/series/79460/
State : warning
== Summary ==
$ dim sparse --fast origin/drm-tip
Sparse version: v0.6.0
Fast mode used, each commit won't be checked separately.
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 33+ messages in thread
* [Intel-gfx] ✗ Fi.CI.BAT: failure for Allow privileged user to map the OA buffer (rev4)
2020-07-22 5:55 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
` (4 preceding siblings ...)
2020-07-22 6:27 ` [Intel-gfx] ✗ Fi.CI.SPARSE: warning for Allow privileged user to map the OA buffer (rev4) Patchwork
@ 2020-07-22 6:48 ` Patchwork
5 siblings, 0 replies; 33+ messages in thread
From: Patchwork @ 2020-07-22 6:48 UTC (permalink / raw)
To: Umesh Nerlige Ramappa; +Cc: intel-gfx
[-- Attachment #1.1: Type: text/plain, Size: 15041 bytes --]
== Series Details ==
Series: Allow privileged user to map the OA buffer (rev4)
URL : https://patchwork.freedesktop.org/series/79460/
State : failure
== Summary ==
CI Bug Log - changes from CI_DRM_8775 -> Patchwork_18221
====================================================
Summary
-------
**FAILURE**
Serious unknown changes coming with Patchwork_18221 absolutely need to be
verified manually.
If you think the reported changes have nothing to do with the changes
introduced in Patchwork_18221, please notify your bug team to allow them
to document this new failure mode, which will reduce false positives in CI.
External URL: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/index.html
Possible new issues
-------------------
Here are the unknown changes that may have been introduced in Patchwork_18221:
### IGT changes ###
#### Possible regressions ####
* igt@i915_selftest@live@workarounds:
- fi-skl-6700k2: [PASS][1] -> [DMESG-FAIL][2]
[1]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-skl-6700k2/igt@i915_selftest@live@workarounds.html
[2]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-skl-6700k2/igt@i915_selftest@live@workarounds.html
- fi-kbl-x1275: [PASS][3] -> [DMESG-FAIL][4]
[3]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-x1275/igt@i915_selftest@live@workarounds.html
[4]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-x1275/igt@i915_selftest@live@workarounds.html
- fi-cfl-guc: [PASS][5] -> [DMESG-FAIL][6]
[5]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-cfl-guc/igt@i915_selftest@live@workarounds.html
[6]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-cfl-guc/igt@i915_selftest@live@workarounds.html
- fi-skl-guc: [PASS][7] -> [DMESG-FAIL][8]
[7]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-skl-guc/igt@i915_selftest@live@workarounds.html
[8]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-skl-guc/igt@i915_selftest@live@workarounds.html
- fi-skl-6600u: [PASS][9] -> [DMESG-FAIL][10]
[9]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-skl-6600u/igt@i915_selftest@live@workarounds.html
[10]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-skl-6600u/igt@i915_selftest@live@workarounds.html
- fi-kbl-8809g: [PASS][11] -> [DMESG-FAIL][12]
[11]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-8809g/igt@i915_selftest@live@workarounds.html
[12]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-8809g/igt@i915_selftest@live@workarounds.html
- fi-cfl-8700k: [PASS][13] -> [DMESG-FAIL][14]
[13]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-cfl-8700k/igt@i915_selftest@live@workarounds.html
[14]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-cfl-8700k/igt@i915_selftest@live@workarounds.html
- fi-kbl-r: NOTRUN -> [DMESG-FAIL][15]
[15]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-r/igt@i915_selftest@live@workarounds.html
- fi-cfl-8109u: [PASS][16] -> [DMESG-FAIL][17]
[16]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-cfl-8109u/igt@i915_selftest@live@workarounds.html
[17]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-cfl-8109u/igt@i915_selftest@live@workarounds.html
- fi-skl-lmem: [PASS][18] -> [DMESG-FAIL][19]
[18]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-skl-lmem/igt@i915_selftest@live@workarounds.html
[19]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-skl-lmem/igt@i915_selftest@live@workarounds.html
- fi-kbl-7500u: [PASS][20] -> [DMESG-FAIL][21]
[20]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-7500u/igt@i915_selftest@live@workarounds.html
[21]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-7500u/igt@i915_selftest@live@workarounds.html
- fi-kbl-guc: [PASS][22] -> [DMESG-FAIL][23]
[22]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-guc/igt@i915_selftest@live@workarounds.html
[23]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-guc/igt@i915_selftest@live@workarounds.html
- fi-kbl-soraka: [PASS][24] -> [DMESG-FAIL][25]
[24]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-soraka/igt@i915_selftest@live@workarounds.html
[25]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-soraka/igt@i915_selftest@live@workarounds.html
#### Suppressed ####
The following results come from untrusted machines, tests, or statuses.
They do not affect the overall result.
* igt@i915_selftest@live@workarounds:
- {fi-kbl-7560u}: [PASS][26] -> [DMESG-FAIL][27]
[26]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-7560u/igt@i915_selftest@live@workarounds.html
[27]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-7560u/igt@i915_selftest@live@workarounds.html
Known issues
------------
Here are the changes found in Patchwork_18221 that come from known issues:
### IGT changes ###
#### Issues hit ####
* igt@debugfs_test@read_all_entries:
- fi-bsw-kefka: [PASS][28] -> [DMESG-WARN][29] ([i915#1982]) +1 similar issue
[28]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-bsw-kefka/igt@debugfs_test@read_all_entries.html
[29]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-bsw-kefka/igt@debugfs_test@read_all_entries.html
* igt@gem_ctx_create@basic:
- fi-tgl-y: [PASS][30] -> [DMESG-WARN][31] ([i915#402]) +1 similar issue
[30]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-tgl-y/igt@gem_ctx_create@basic.html
[31]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-tgl-y/igt@gem_ctx_create@basic.html
* igt@i915_pm_rpm@module-reload:
- fi-byt-j1900: [PASS][32] -> [DMESG-WARN][33] ([i915#1982])
[32]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-byt-j1900/igt@i915_pm_rpm@module-reload.html
[33]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-byt-j1900/igt@i915_pm_rpm@module-reload.html
* igt@i915_selftest@live@workarounds:
- fi-apl-guc: [PASS][34] -> [DMESG-FAIL][35] ([i915#1635])
[34]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-apl-guc/igt@i915_selftest@live@workarounds.html
[35]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-apl-guc/igt@i915_selftest@live@workarounds.html
- fi-bxt-dsi: [PASS][36] -> [DMESG-FAIL][37] ([i915#1635])
[36]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-bxt-dsi/igt@i915_selftest@live@workarounds.html
[37]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-bxt-dsi/igt@i915_selftest@live@workarounds.html
* igt@kms_cursor_legacy@basic-busy-flip-before-cursor-atomic:
- fi-bsw-n3050: [PASS][38] -> [DMESG-WARN][39] ([i915#1982]) +1 similar issue
[38]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-bsw-n3050/igt@kms_cursor_legacy@basic-busy-flip-before-cursor-atomic.html
[39]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-bsw-n3050/igt@kms_cursor_legacy@basic-busy-flip-before-cursor-atomic.html
* igt@kms_cursor_legacy@basic-flip-before-cursor-legacy:
- fi-icl-u2: [PASS][40] -> [DMESG-WARN][41] ([i915#1982])
[40]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-icl-u2/igt@kms_cursor_legacy@basic-flip-before-cursor-legacy.html
[41]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-icl-u2/igt@kms_cursor_legacy@basic-flip-before-cursor-legacy.html
* igt@kms_flip@basic-flip-vs-wf_vblank@c-hdmi-a2:
- fi-skl-guc: [PASS][42] -> [DMESG-WARN][43] ([i915#2203])
[42]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-skl-guc/igt@kms_flip@basic-flip-vs-wf_vblank@c-hdmi-a2.html
[43]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-skl-guc/igt@kms_flip@basic-flip-vs-wf_vblank@c-hdmi-a2.html
#### Possible fixes ####
* igt@i915_module_load@reload:
- {fi-tgl-dsi}: [DMESG-WARN][44] ([i915#1982]) -> [PASS][45]
[44]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-tgl-dsi/igt@i915_module_load@reload.html
[45]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-tgl-dsi/igt@i915_module_load@reload.html
- fi-apl-guc: [DMESG-WARN][46] ([i915#1635] / [i915#1982]) -> [PASS][47]
[46]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-apl-guc/igt@i915_module_load@reload.html
[47]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-apl-guc/igt@i915_module_load@reload.html
* igt@i915_pm_rpm@basic-pci-d3-state:
- fi-byt-j1900: [DMESG-WARN][48] ([i915#1982]) -> [PASS][49]
[48]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-byt-j1900/igt@i915_pm_rpm@basic-pci-d3-state.html
[49]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-byt-j1900/igt@i915_pm_rpm@basic-pci-d3-state.html
* igt@i915_pm_rpm@module-reload:
- fi-bsw-kefka: [DMESG-WARN][50] ([i915#1982]) -> [PASS][51] +2 similar issues
[50]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-bsw-kefka/igt@i915_pm_rpm@module-reload.html
[51]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-bsw-kefka/igt@i915_pm_rpm@module-reload.html
* igt@i915_selftest@live@active:
- fi-cfl-8109u: [DMESG-FAIL][52] ([i915#666]) -> [PASS][53]
[52]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-cfl-8109u/igt@i915_selftest@live@active.html
[53]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-cfl-8109u/igt@i915_selftest@live@active.html
* igt@kms_busy@basic@flip:
- fi-kbl-x1275: [DMESG-WARN][54] ([i915#62] / [i915#92] / [i915#95]) -> [PASS][55]
[54]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-x1275/igt@kms_busy@basic@flip.html
[55]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-x1275/igt@kms_busy@basic@flip.html
- fi-tgl-y: [DMESG-WARN][56] ([i915#1982]) -> [PASS][57] +1 similar issue
[56]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-tgl-y/igt@kms_busy@basic@flip.html
[57]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-tgl-y/igt@kms_busy@basic@flip.html
* igt@kms_chamelium@common-hpd-after-suspend:
- fi-kbl-7500u: [DMESG-WARN][58] ([i915#2203]) -> [PASS][59]
[58]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-7500u/igt@kms_chamelium@common-hpd-after-suspend.html
[59]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-7500u/igt@kms_chamelium@common-hpd-after-suspend.html
* igt@kms_pipe_crc_basic@read-crc-pipe-a-frame-sequence:
- fi-tgl-u2: [DMESG-WARN][60] ([i915#402]) -> [PASS][61]
[60]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-tgl-u2/igt@kms_pipe_crc_basic@read-crc-pipe-a-frame-sequence.html
[61]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-tgl-u2/igt@kms_pipe_crc_basic@read-crc-pipe-a-frame-sequence.html
* igt@prime_self_import@basic-with_two_bos:
- fi-tgl-y: [DMESG-WARN][62] ([i915#402]) -> [PASS][63] +1 similar issue
[62]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-tgl-y/igt@prime_self_import@basic-with_two_bos.html
[63]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-tgl-y/igt@prime_self_import@basic-with_two_bos.html
#### Warnings ####
* igt@i915_module_load@reload:
- fi-icl-u2: [DMESG-WARN][64] ([i915#1982] / [i915#289]) -> [DMESG-WARN][65] ([i915#289])
[64]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-icl-u2/igt@i915_module_load@reload.html
[65]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-icl-u2/igt@i915_module_load@reload.html
* igt@i915_pm_rpm@basic-rte:
- fi-kbl-guc: [SKIP][66] ([fdo#109271]) -> [DMESG-FAIL][67] ([i915#2203])
[66]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-guc/igt@i915_pm_rpm@basic-rte.html
[67]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-guc/igt@i915_pm_rpm@basic-rte.html
* igt@kms_force_connector_basic@force-connector-state:
- fi-kbl-x1275: [DMESG-WARN][68] ([i915#62] / [i915#92]) -> [DMESG-WARN][69] ([i915#62] / [i915#92] / [i915#95]) +1 similar issue
[68]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-x1275/igt@kms_force_connector_basic@force-connector-state.html
[69]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-x1275/igt@kms_force_connector_basic@force-connector-state.html
* igt@kms_force_connector_basic@force-edid:
- fi-kbl-x1275: [DMESG-WARN][70] ([i915#62] / [i915#92] / [i915#95]) -> [DMESG-WARN][71] ([i915#62] / [i915#92]) +3 similar issues
[70]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_8775/fi-kbl-x1275/igt@kms_force_connector_basic@force-edid.html
[71]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/fi-kbl-x1275/igt@kms_force_connector_basic@force-edid.html
{name}: This element is suppressed. This means it is ignored when computing
the status of the difference (SUCCESS, WARNING, or FAILURE).
[fdo#109271]: https://bugs.freedesktop.org/show_bug.cgi?id=109271
[i915#1635]: https://gitlab.freedesktop.org/drm/intel/issues/1635
[i915#1982]: https://gitlab.freedesktop.org/drm/intel/issues/1982
[i915#2203]: https://gitlab.freedesktop.org/drm/intel/issues/2203
[i915#289]: https://gitlab.freedesktop.org/drm/intel/issues/289
[i915#402]: https://gitlab.freedesktop.org/drm/intel/issues/402
[i915#62]: https://gitlab.freedesktop.org/drm/intel/issues/62
[i915#666]: https://gitlab.freedesktop.org/drm/intel/issues/666
[i915#92]: https://gitlab.freedesktop.org/drm/intel/issues/92
[i915#95]: https://gitlab.freedesktop.org/drm/intel/issues/95
Participating hosts (47 -> 40)
------------------------------
Missing (7): fi-ilk-m540 fi-hsw-4200u fi-byt-squawks fi-bsw-cyan fi-ctg-p8600 fi-byt-clapper fi-bdw-samus
Build changes
-------------
* IGT: IGT_5742 -> IGTPW_4788
* Linux: CI_DRM_8775 -> Patchwork_18221
CI-20190529: 20190529
CI_DRM_8775: 2dc052ea981f79cb758997ffa762fe4ea18ef9ca @ git://anongit.freedesktop.org/gfx-ci/linux
IGTPW_4788: https://intel-gfx-ci.01.org/tree/drm-tip/IGTPW_4788/index.html
IGT_5742: 540f9de91ab2816885a9076a4c0835cb3dc67a97 @ git://anongit.freedesktop.org/xorg/app/intel-gpu-tools
Patchwork_18221: bab0da323556d2819afea0d012f4ffff7f7410dd @ git://anongit.freedesktop.org/gfx-ci/linux
== Linux commits ==
bab0da323556 drm/i915/perf: Map OA buffer to user space for gen12 performance query
ef7adc915aec drm/i915/perf: Whitelist OA counter and buffer registers
07511bbc9441 drm/i915/perf: Whitelist OA report trigger registers
ddc28fbf91e1 drm/i915/perf: Ensure observation logic is not clock gated
== Logs ==
For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_18221/index.html
[-- Attachment #1.2: Type: text/html, Size: 18175 bytes --]
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_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-22 5:55 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
@ 2020-07-23 9:31 ` Lionel Landwerlin
2020-07-23 23:48 ` Umesh Nerlige Ramappa
0 siblings, 1 reply; 33+ messages in thread
From: Lionel Landwerlin @ 2020-07-23 9:31 UTC (permalink / raw)
To: Umesh Nerlige Ramappa, intel-gfx; +Cc: Chris Wilson
On 22/07/2020 08:55, Umesh Nerlige Ramappa wrote:
> From: Piotr Maciejewski <piotr.maciejewski@intel.com>
>
> i915 used to support time based sampling mode which is good for overall
> system monitoring, but is not enough for query mode used to measure a
> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
> implementation for query, but Gen12+ requires a new approach for query
> based on triggered reports within oa buffer.
>
> Triggering reports into the OA buffer is achieved by writing into a
> a trigger register. Optionally an unused counter/register is set with a
> marker value such that a triggered report can be identified in the OA
> buffer. Reports are usually triggered at the start and end of work that
> is measured.
>
> Since OA buffer is large and queries can be frequent, an efficient way
> to look for triggered reports is required. By knowing the current head
> and tail offsets into the OA buffer, it is easier to determine the
> locality of the reports of interest.
>
> Current perf OA interface does not expose head/tail information to the
> user and it filters out invalid reports before sending data to user.
> Also considering limited size of user buffer used during a query,
> creating a 1:1 copy of the OA buffer at the user space added undesired
> complexity.
>
> The solution was to map the OA buffer to user space provided
>
> (1) that it is accessed from a privileged user.
> (2) OA report filtering is not used.
>
> These 2 conditions would satisfy the safety criteria that the current
> perf interface addresses.
>
> To enable the query:
> - Add an ioctl to expose head and tail to the user
> - Add an ioctl to return size and offset of the OA buffer
> - Map the OA buffer to the user space
>
> v2:
> - Improve commit message (Chris)
> - Do not mmap based on gem object filp. Instead, use perf_fd and support
> mmap syscall (Chris)
> - Pass non-zero offset in mmap to enforce the right object is
> mapped (Chris)
> - Do not expose gpu_address (Chris)
> - Verify start and length of vma for page alignment (Lionel)
> - Move SQNTL config out (Lionel)
>
> v3: (Chris)
> - Omit redundant checks
> - Return VM_FAULT_SIGBUS is old stream is closed
> - Maintain reference counts to stream in vm_open and vm_close
> - Use switch to identify object to be mapped
>
> v4: Call kref_put on closing perf fd (Chris)
>
> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> ---
> drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
> drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
> drivers/gpu/drm/i915/i915_perf.c | 211 ++++++++++++++++++++++-
> drivers/gpu/drm/i915/i915_perf_types.h | 17 ++
> include/uapi/drm/i915_drm.h | 32 ++++
> 5 files changed, 261 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> index b23368529a40..7c4b9b0c334b 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> @@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
> return view;
> }
>
> -static vm_fault_t i915_error_to_vmf_fault(int err)
> +vm_fault_t i915_error_to_vmf_fault(int err)
> {
> switch (err) {
> default:
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
> index efee9e0d2508..1190a3a228ea 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
> @@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
>
> void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
>
> +vm_fault_t i915_error_to_vmf_fault(int err);
> +
> #endif
> diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
> index 2f23aad12c60..331c3f9c59e2 100644
> --- a/drivers/gpu/drm/i915/i915_perf.c
> +++ b/drivers/gpu/drm/i915/i915_perf.c
> @@ -192,10 +192,12 @@
> */
>
> #include <linux/anon_inodes.h>
> +#include <linux/mman.h>
> #include <linux/sizes.h>
> #include <linux/uuid.h>
>
> #include "gem/i915_gem_context.h"
> +#include "gem/i915_gem_mman.h"
> #include "gt/intel_engine_pm.h"
> #include "gt/intel_engine_user.h"
> #include "gt/intel_gt.h"
> @@ -378,6 +380,24 @@ static struct ctl_table_header *sysctl_header;
>
> static enum hrtimer_restart oa_poll_check_timer_cb(struct hrtimer *hrtimer);
>
> +static void free_stream(struct kref *kref)
> +{
> + struct i915_perf_stream *stream =
> + container_of(kref, typeof(*stream), refcount);
> +
> + kfree(stream);
> +}
> +
> +static void perf_stream_get(struct i915_perf_stream *stream)
> +{
> + kref_get(&stream->refcount);
> +}
> +
> +static void perf_stream_put(struct i915_perf_stream *stream)
> +{
> + kref_put(&stream->refcount, free_stream);
> +}
> +
> void i915_oa_config_release(struct kref *ref)
> {
> struct i915_oa_config *oa_config =
> @@ -434,6 +454,30 @@ static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream)
> return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;
> }
>
> +static u32 gen12_oa_hw_head_read(struct i915_perf_stream *stream)
> +{
> + struct intel_uncore *uncore = stream->uncore;
> +
> + return intel_uncore_read(uncore, GEN12_OAG_OAHEADPTR) &
> + GEN12_OAG_OAHEADPTR_MASK;
> +}
> +
> +static u32 gen8_oa_hw_head_read(struct i915_perf_stream *stream)
> +{
> + struct intel_uncore *uncore = stream->uncore;
> +
> + return intel_uncore_read(uncore, GEN8_OAHEADPTR) &
> + GEN8_OAHEADPTR_MASK;
> +}
> +
> +static u32 gen7_oa_hw_head_read(struct i915_perf_stream *stream)
> +{
> + struct intel_uncore *uncore = stream->uncore;
> + u32 oastatus2 = intel_uncore_read(uncore, GEN7_OASTATUS2);
> +
> + return oastatus2 & GEN7_OASTATUS2_HEAD_MASK;
> +}
> +
> /**
> * oa_buffer_check_unlocked - check for data and update tail ptr state
> * @stream: i915 stream instance
> @@ -2934,6 +2978,7 @@ static int i915_oa_stream_init(struct i915_perf_stream *stream,
> stream->poll_check_timer.function = oa_poll_check_timer_cb;
> init_waitqueue_head(&stream->poll_wq);
> spin_lock_init(&stream->oa_buffer.ptr_lock);
> + kref_init(&stream->refcount);
>
> return 0;
>
> @@ -3214,6 +3259,69 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
> return ret;
> }
>
> +/**
> + * i915_perf_oa_buffer_head_tail_locked - head and tail of the OA buffer
> + * @stream: i915 perf stream
> + * @arg: pointer to oa buffer head and tail filled by this function.
> + */
> +static int i915_perf_oa_buffer_head_tail_locked(struct i915_perf_stream *stream,
> + unsigned long arg)
> +{
> + struct drm_i915_perf_oa_buffer_head_tail ht;
> + void __user *output = (void __user *)arg;
> + u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
> +
> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
> + DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
> + return -EACCES;
> + }
> +
> + if (!output)
> + return -EINVAL;
> +
> + memset(&ht, 0, sizeof(ht));
> +
> + ht.head = stream->perf->ops.oa_hw_head_read(stream) - gtt_offset;
> + ht.tail = stream->perf->ops.oa_hw_tail_read(stream) - gtt_offset;
> +
> + if (copy_to_user(output, &ht, sizeof(ht)))
> + return -EFAULT;
> +
> + return 0;
> +}
> +
> +#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
> +
> +/**
> + * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
> + * @stream: i915 perf stream
> + * @arg: pointer to oa buffer info filled by this function.
> + */
> +static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
> + unsigned long arg)
> +{
> + struct drm_i915_perf_oa_buffer_info info;
> + void __user *output = (void __user *)arg;
> +
> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
> + DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
> + return -EACCES;
> + }
> +
> + if (!output)
> + return -EINVAL;
> +
> + memset(&info, 0, sizeof(info));
> +
> + info.size = stream->oa_buffer.vma->size;
> + info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
> +
> + if (copy_to_user(output, &info, sizeof(info)))
> + return -EFAULT;
> +
> + return 0;
> +}
> +
> /**
> * i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
> * @stream: An i915 perf stream
> @@ -3239,6 +3347,10 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
> return 0;
> case I915_PERF_IOCTL_CONFIG:
> return i915_perf_config_locked(stream, arg);
> + case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
> + return i915_perf_oa_buffer_info_locked(stream, arg);
> + case I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL:
> + return i915_perf_oa_buffer_head_tail_locked(stream, arg);
> }
>
> return -EINVAL;
> @@ -3291,7 +3403,8 @@ static void i915_perf_destroy_locked(struct i915_perf_stream *stream)
> if (stream->ctx)
> i915_gem_context_put(stream->ctx);
>
> - kfree(stream);
> + WRITE_ONCE(stream->closed, true);
> + perf_stream_put(stream);
> }
>
> /**
> @@ -3314,12 +3427,98 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> i915_perf_destroy_locked(stream);
> mutex_unlock(&perf->lock);
>
> + unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
> +
> /* Release the reference the perf stream kept on the driver. */
> drm_dev_put(&perf->i915->drm);
>
> return 0;
> }
>
> +static void vm_open_oa(struct vm_area_struct *vma)
> +{
> + struct i915_perf_stream *stream = vma->vm_private_data;
> +
> + GEM_BUG_ON(!stream);
> + perf_stream_get(stream);
> +}
> +
> +static void vm_close_oa(struct vm_area_struct *vma)
> +{
> + struct i915_perf_stream *stream = vma->vm_private_data;
> +
> + GEM_BUG_ON(!stream);
> + perf_stream_put(stream);
> +}
> +
> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
> +{
> + struct vm_area_struct *vma = vmf->vma;
> + struct i915_perf_stream *stream = vma->vm_private_data;
> + struct i915_perf *perf = stream->perf;
> + struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
I could be wrong because I'm not that knowledgeable on memory mapping stuff.
But it seems if close() is called on the i915-perf stream before this
function is called. stream->oa_buffer.vma might be NULL/freed.
It seems like we need an additional reference on the
stream->oa_buffer.vma->obj taken within the perf->lock in this function.
If you notice the stream->oa_buffer.vaddr is NULL inside the lock, it
means a close() call won the race with the mmap() and you should return
VM_FAULT_SIGBUS.
We should drop that reference taken on stream->oa_buffer.vma->obj when
the memory is unmapped.
Maybe Chris can confirm if that sounds correct.
-Lionel
> + int err;
> + bool closed;
> +
> + mutex_lock(&perf->lock);
> + closed = READ_ONCE(stream->closed);
> + mutex_unlock(&perf->lock);
> +
> + if (closed)
> + return VM_FAULT_SIGBUS;
> +
> + err = i915_gem_object_pin_pages(obj);
> + if (err)
> + goto out;
> +
> + err = remap_io_sg(vma,
> + vma->vm_start, vma->vm_end - vma->vm_start,
> + obj->mm.pages->sgl, -1);
> +
> + i915_gem_object_unpin_pages(obj);
> +
> +out:
> + return i915_error_to_vmf_fault(err);
> +}
> +
> +static const struct vm_operations_struct vm_ops_oa = {
> + .open = vm_open_oa,
> + .close = vm_close_oa,
> + .fault = vm_fault_oa,
> +};
> +
> +int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
> +{
> + struct i915_perf_stream *stream = file->private_data;
> +
> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
> + DRM_DEBUG("Insufficient privileges to map OA buffer\n");
> + return -EACCES;
> + }
> +
> + switch (vma->vm_pgoff) {
> + case I915_PERF_OA_BUFFER_MMAP_OFFSET:
> + if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
> + return -EINVAL;
> +
> + if (vma->vm_flags & VM_WRITE)
> + return -EINVAL;
> +
> + break;
> +
> + default:
> + return -EINVAL;
> + }
> +
> + vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC | VM_MAYSHARE);
> + vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
> + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
> + vma->vm_private_data = stream;
> + vma->vm_ops = &vm_ops_oa;
> + vm_open_oa(vma);
> +
> + return 0;
> +}
>
> static const struct file_operations fops = {
> .owner = THIS_MODULE,
> @@ -3332,6 +3531,7 @@ static const struct file_operations fops = {
> * to handle 32bits compatibility.
> */
> .compat_ioctl = i915_perf_ioctl,
> + .mmap = i915_perf_mmap,
> };
>
>
> @@ -4260,6 +4460,7 @@ void i915_perf_init(struct drm_i915_private *i915)
> perf->ops.oa_disable = gen7_oa_disable;
> perf->ops.read = gen7_oa_read;
> perf->ops.oa_hw_tail_read = gen7_oa_hw_tail_read;
> + perf->ops.oa_hw_head_read = gen7_oa_hw_head_read;
>
> perf->oa_formats = hsw_oa_formats;
> } else if (HAS_LOGICAL_RING_CONTEXTS(i915)) {
> @@ -4291,6 +4492,7 @@ void i915_perf_init(struct drm_i915_private *i915)
> perf->ops.enable_metric_set = gen8_enable_metric_set;
> perf->ops.disable_metric_set = gen8_disable_metric_set;
> perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
> + perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
>
> if (IS_GEN(i915, 8)) {
> perf->ctx_oactxctrl_offset = 0x120;
> @@ -4318,6 +4520,7 @@ void i915_perf_init(struct drm_i915_private *i915)
> perf->ops.enable_metric_set = gen8_enable_metric_set;
> perf->ops.disable_metric_set = gen10_disable_metric_set;
> perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
> + perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
>
> if (IS_GEN(i915, 10)) {
> perf->ctx_oactxctrl_offset = 0x128;
> @@ -4342,6 +4545,7 @@ void i915_perf_init(struct drm_i915_private *i915)
> perf->ops.enable_metric_set = gen12_enable_metric_set;
> perf->ops.disable_metric_set = gen12_disable_metric_set;
> perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
> + perf->ops.oa_hw_head_read = gen12_oa_hw_head_read;
>
> perf->ctx_flexeu0_offset = 0;
> perf->ctx_oactxctrl_offset = 0x144;
> @@ -4456,8 +4660,11 @@ int i915_perf_ioctl_version(void)
> *
> * - OA buffer head/tail/status/buffer registers for read only
> * - OA counters A18, A19, A20 for read/write
> + *
> + * 8: Added an option to map oa buffer at umd driver level and trigger
> + * oa reports within oa buffer from command buffer.
> */
> - return 7;
> + return 8;
> }
>
> #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
> diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
> index a36a455ae336..2efbe35c5fa9 100644
> --- a/drivers/gpu/drm/i915/i915_perf_types.h
> +++ b/drivers/gpu/drm/i915/i915_perf_types.h
> @@ -311,6 +311,18 @@ struct i915_perf_stream {
> * buffer should be checked for available data.
> */
> u64 poll_oa_period;
> +
> + /**
> + * @closed: Open or closed state of the stream.
> + * True if stream is closed.
> + */
> + bool closed;
> +
> + /**
> + * @refcount: References to the mapped OA buffer managed by this
> + * stream.
> + */
> + struct kref refcount;
> };
>
> /**
> @@ -377,6 +389,11 @@ struct i915_oa_ops {
> * generations.
> */
> u32 (*oa_hw_tail_read)(struct i915_perf_stream *stream);
> +
> + /**
> + * @oa_hw_head_read: read the OA head pointer register
> + */
> + u32 (*oa_hw_head_read)(struct i915_perf_stream *stream);
> };
>
> struct i915_perf {
> diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
> index 00546062e023..2042f6339182 100644
> --- a/include/uapi/drm/i915_drm.h
> +++ b/include/uapi/drm/i915_drm.h
> @@ -2048,6 +2048,38 @@ struct drm_i915_perf_open_param {
> */
> #define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
>
> +/**
> + * Returns OA buffer properties to be used with mmap.
> + *
> + * This ioctl is available in perf revision 8.
> + */
> +#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IO('i', 0x3)
> +
> +/**
> + * OA buffer size and offset.
> + */
> +struct drm_i915_perf_oa_buffer_info {
> + __u32 size;
> + __u32 offset;
> + __u64 reserved[4];
> +};
> +
> +/**
> + * Returns current position of OA buffer head and tail.
> + *
> + * This ioctl is available in perf revision 8.
> + */
> +#define I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL _IO('i', 0x4)
> +
> +/**
> + * OA buffer head and tail.
> + */
> +struct drm_i915_perf_oa_buffer_head_tail {
> + __u32 head;
> + __u32 tail;
> + __u64 reserved[4];
> +};
> +
> /**
> * Common to all i915 perf records
> */
_______________________________________________
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^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-23 9:31 ` Lionel Landwerlin
@ 2020-07-23 23:48 ` Umesh Nerlige Ramappa
0 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-23 23:48 UTC (permalink / raw)
To: Lionel Landwerlin; +Cc: intel-gfx, Chris Wilson
On Thu, Jul 23, 2020 at 12:31:30PM +0300, Lionel Landwerlin wrote:
>On 22/07/2020 08:55, Umesh Nerlige Ramappa wrote:
>>From: Piotr Maciejewski <piotr.maciejewski@intel.com>
>>
>>i915 used to support time based sampling mode which is good for overall
>>system monitoring, but is not enough for query mode used to measure a
>>single draw call or dispatch. Gen9-Gen11 are using current i915 perf
>>implementation for query, but Gen12+ requires a new approach for query
>>based on triggered reports within oa buffer.
>>
>>Triggering reports into the OA buffer is achieved by writing into a
>>a trigger register. Optionally an unused counter/register is set with a
>>marker value such that a triggered report can be identified in the OA
>>buffer. Reports are usually triggered at the start and end of work that
>>is measured.
>>
>>Since OA buffer is large and queries can be frequent, an efficient way
>>to look for triggered reports is required. By knowing the current head
>>and tail offsets into the OA buffer, it is easier to determine the
>>locality of the reports of interest.
>>
>>Current perf OA interface does not expose head/tail information to the
>>user and it filters out invalid reports before sending data to user.
>>Also considering limited size of user buffer used during a query,
>>creating a 1:1 copy of the OA buffer at the user space added undesired
>>complexity.
>>
>>The solution was to map the OA buffer to user space provided
>>
>>(1) that it is accessed from a privileged user.
>>(2) OA report filtering is not used.
>>
>>These 2 conditions would satisfy the safety criteria that the current
>>perf interface addresses.
>>
>>To enable the query:
>>- Add an ioctl to expose head and tail to the user
>>- Add an ioctl to return size and offset of the OA buffer
>>- Map the OA buffer to the user space
>>
>>v2:
>>- Improve commit message (Chris)
>>- Do not mmap based on gem object filp. Instead, use perf_fd and support
>> mmap syscall (Chris)
>>- Pass non-zero offset in mmap to enforce the right object is
>> mapped (Chris)
>>- Do not expose gpu_address (Chris)
>>- Verify start and length of vma for page alignment (Lionel)
>>- Move SQNTL config out (Lionel)
>>
>>v3: (Chris)
>>- Omit redundant checks
>>- Return VM_FAULT_SIGBUS is old stream is closed
>>- Maintain reference counts to stream in vm_open and vm_close
>>- Use switch to identify object to be mapped
>>
>>v4: Call kref_put on closing perf fd (Chris)
>>
>>Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
>>Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
>>---
>> drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
>> drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
>> drivers/gpu/drm/i915/i915_perf.c | 211 ++++++++++++++++++++++-
>> drivers/gpu/drm/i915/i915_perf_types.h | 17 ++
>> include/uapi/drm/i915_drm.h | 32 ++++
>> 5 files changed, 261 insertions(+), 3 deletions(-)
>>
>>diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
>>index b23368529a40..7c4b9b0c334b 100644
>>--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
>>+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
>>@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
>> return view;
>> }
>>-static vm_fault_t i915_error_to_vmf_fault(int err)
>>+vm_fault_t i915_error_to_vmf_fault(int err)
>> {
>> switch (err) {
>> default:
>>diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
>>index efee9e0d2508..1190a3a228ea 100644
>>--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
>>+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
>>@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
>> void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
>>+vm_fault_t i915_error_to_vmf_fault(int err);
>>+
>> #endif
>>diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
>>index 2f23aad12c60..331c3f9c59e2 100644
>>--- a/drivers/gpu/drm/i915/i915_perf.c
>>+++ b/drivers/gpu/drm/i915/i915_perf.c
>>@@ -192,10 +192,12 @@
>> */
>> #include <linux/anon_inodes.h>
>>+#include <linux/mman.h>
>> #include <linux/sizes.h>
>> #include <linux/uuid.h>
>> #include "gem/i915_gem_context.h"
>>+#include "gem/i915_gem_mman.h"
>> #include "gt/intel_engine_pm.h"
>> #include "gt/intel_engine_user.h"
>> #include "gt/intel_gt.h"
>>@@ -378,6 +380,24 @@ static struct ctl_table_header *sysctl_header;
>> static enum hrtimer_restart oa_poll_check_timer_cb(struct hrtimer *hrtimer);
>>+static void free_stream(struct kref *kref)
>>+{
>>+ struct i915_perf_stream *stream =
>>+ container_of(kref, typeof(*stream), refcount);
>>+
>>+ kfree(stream);
>>+}
>>+
>>+static void perf_stream_get(struct i915_perf_stream *stream)
>>+{
>>+ kref_get(&stream->refcount);
>>+}
>>+
>>+static void perf_stream_put(struct i915_perf_stream *stream)
>>+{
>>+ kref_put(&stream->refcount, free_stream);
>>+}
>>+
>> void i915_oa_config_release(struct kref *ref)
>> {
>> struct i915_oa_config *oa_config =
>>@@ -434,6 +454,30 @@ static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream)
>> return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;
>> }
>>+static u32 gen12_oa_hw_head_read(struct i915_perf_stream *stream)
>>+{
>>+ struct intel_uncore *uncore = stream->uncore;
>>+
>>+ return intel_uncore_read(uncore, GEN12_OAG_OAHEADPTR) &
>>+ GEN12_OAG_OAHEADPTR_MASK;
>>+}
>>+
>>+static u32 gen8_oa_hw_head_read(struct i915_perf_stream *stream)
>>+{
>>+ struct intel_uncore *uncore = stream->uncore;
>>+
>>+ return intel_uncore_read(uncore, GEN8_OAHEADPTR) &
>>+ GEN8_OAHEADPTR_MASK;
>>+}
>>+
>>+static u32 gen7_oa_hw_head_read(struct i915_perf_stream *stream)
>>+{
>>+ struct intel_uncore *uncore = stream->uncore;
>>+ u32 oastatus2 = intel_uncore_read(uncore, GEN7_OASTATUS2);
>>+
>>+ return oastatus2 & GEN7_OASTATUS2_HEAD_MASK;
>>+}
>>+
>> /**
>> * oa_buffer_check_unlocked - check for data and update tail ptr state
>> * @stream: i915 stream instance
>>@@ -2934,6 +2978,7 @@ static int i915_oa_stream_init(struct i915_perf_stream *stream,
>> stream->poll_check_timer.function = oa_poll_check_timer_cb;
>> init_waitqueue_head(&stream->poll_wq);
>> spin_lock_init(&stream->oa_buffer.ptr_lock);
>>+ kref_init(&stream->refcount);
>> return 0;
>>@@ -3214,6 +3259,69 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
>> return ret;
>> }
>>+/**
>>+ * i915_perf_oa_buffer_head_tail_locked - head and tail of the OA buffer
>>+ * @stream: i915 perf stream
>>+ * @arg: pointer to oa buffer head and tail filled by this function.
>>+ */
>>+static int i915_perf_oa_buffer_head_tail_locked(struct i915_perf_stream *stream,
>>+ unsigned long arg)
>>+{
>>+ struct drm_i915_perf_oa_buffer_head_tail ht;
>>+ void __user *output = (void __user *)arg;
>>+ u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
>>+
>>+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
>>+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
>>+ return -EACCES;
>>+ }
>>+
>>+ if (!output)
>>+ return -EINVAL;
>>+
>>+ memset(&ht, 0, sizeof(ht));
>>+
>>+ ht.head = stream->perf->ops.oa_hw_head_read(stream) - gtt_offset;
>>+ ht.tail = stream->perf->ops.oa_hw_tail_read(stream) - gtt_offset;
>>+
>>+ if (copy_to_user(output, &ht, sizeof(ht)))
>>+ return -EFAULT;
>>+
>>+ return 0;
>>+}
>>+
>>+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
>>+
>>+/**
>>+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
>>+ * @stream: i915 perf stream
>>+ * @arg: pointer to oa buffer info filled by this function.
>>+ */
>>+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
>>+ unsigned long arg)
>>+{
>>+ struct drm_i915_perf_oa_buffer_info info;
>>+ void __user *output = (void __user *)arg;
>>+
>>+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
>>+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
>>+ return -EACCES;
>>+ }
>>+
>>+ if (!output)
>>+ return -EINVAL;
>>+
>>+ memset(&info, 0, sizeof(info));
>>+
>>+ info.size = stream->oa_buffer.vma->size;
>>+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
>>+
>>+ if (copy_to_user(output, &info, sizeof(info)))
>>+ return -EFAULT;
>>+
>>+ return 0;
>>+}
>>+
>> /**
>> * i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
>> * @stream: An i915 perf stream
>>@@ -3239,6 +3347,10 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
>> return 0;
>> case I915_PERF_IOCTL_CONFIG:
>> return i915_perf_config_locked(stream, arg);
>>+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
>>+ return i915_perf_oa_buffer_info_locked(stream, arg);
>>+ case I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL:
>>+ return i915_perf_oa_buffer_head_tail_locked(stream, arg);
>> }
>> return -EINVAL;
>>@@ -3291,7 +3403,8 @@ static void i915_perf_destroy_locked(struct i915_perf_stream *stream)
>> if (stream->ctx)
>> i915_gem_context_put(stream->ctx);
>>- kfree(stream);
>>+ WRITE_ONCE(stream->closed, true);
>>+ perf_stream_put(stream);
>> }
>> /**
>>@@ -3314,12 +3427,98 @@ static int i915_perf_release(struct inode *inode, struct file *file)
>> i915_perf_destroy_locked(stream);
>> mutex_unlock(&perf->lock);
>>+ unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
>>+
>> /* Release the reference the perf stream kept on the driver. */
>> drm_dev_put(&perf->i915->drm);
>> return 0;
>> }
>>+static void vm_open_oa(struct vm_area_struct *vma)
>>+{
>>+ struct i915_perf_stream *stream = vma->vm_private_data;
>>+
>>+ GEM_BUG_ON(!stream);
>>+ perf_stream_get(stream);
>>+}
>>+
>>+static void vm_close_oa(struct vm_area_struct *vma)
>>+{
>>+ struct i915_perf_stream *stream = vma->vm_private_data;
>>+
>>+ GEM_BUG_ON(!stream);
>>+ perf_stream_put(stream);
>>+}
>>+
>>+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
>>+{
>>+ struct vm_area_struct *vma = vmf->vma;
>>+ struct i915_perf_stream *stream = vma->vm_private_data;
>>+ struct i915_perf *perf = stream->perf;
>>+ struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
>
>I could be wrong because I'm not that knowledgeable on memory mapping stuff.
>
>But it seems if close() is called on the i915-perf stream before this
>function is called. stream->oa_buffer.vma might be NULL/freed.
>
>
>It seems like we need an additional reference on the
>stream->oa_buffer.vma->obj taken within the perf->lock in this
>function. If you notice the stream->oa_buffer.vaddr is NULL inside the
>lock, it means a close() call won the race with the mmap() and you
>should return VM_FAULT_SIGBUS.
>
>We should drop that reference taken on stream->oa_buffer.vma->obj when
>the memory is unmapped.
>
Based on trying to trigger a SIGBUS with igt, this is what I found:
do_mmap (somewhere in mmap_region) takes a reference to the file. If oa
buffer is mapped successfully, close(perf_fd) does not call
i915_perf_release, but close(perf_fd) followed by unmap() or vice-versa
will end up calling i915_perf_release.
forking did not help either because fork itself takes a reference to the
perf_fd.
Once unmap is called, the vma should be gone anyways, so I don't expect
the kernel to call vm_fault. I would say the kernel is really smart and
wouldn't let it happen :), but maybe Chris can confirm.
Thanks,
Umesh
>
>Maybe Chris can confirm if that sounds correct.
>
>
>-Lionel
>
>
>>+ int err;
>>+ bool closed;
>>+
>>+ mutex_lock(&perf->lock);
>>+ closed = READ_ONCE(stream->closed);
>>+ mutex_unlock(&perf->lock);
>>+
>>+ if (closed)
>>+ return VM_FAULT_SIGBUS;
>>+
>>+ err = i915_gem_object_pin_pages(obj);
>>+ if (err)
>>+ goto out;
>>+
>>+ err = remap_io_sg(vma,
>>+ vma->vm_start, vma->vm_end - vma->vm_start,
>>+ obj->mm.pages->sgl, -1);
>>+
>>+ i915_gem_object_unpin_pages(obj);
>>+
>>+out:
>>+ return i915_error_to_vmf_fault(err);
>>+}
>>+
>>+static const struct vm_operations_struct vm_ops_oa = {
>>+ .open = vm_open_oa,
>>+ .close = vm_close_oa,
>>+ .fault = vm_fault_oa,
>>+};
>>+
>>+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
>>+{
>>+ struct i915_perf_stream *stream = file->private_data;
>>+
>>+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
>>+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
>>+ return -EACCES;
>>+ }
>>+
>>+ switch (vma->vm_pgoff) {
>>+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
>>+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
>>+ return -EINVAL;
>>+
>>+ if (vma->vm_flags & VM_WRITE)
>>+ return -EINVAL;
>>+
>>+ break;
>>+
>>+ default:
>>+ return -EINVAL;
>>+ }
>>+
>>+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC | VM_MAYSHARE);
>>+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
>>+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
>>+ vma->vm_private_data = stream;
>>+ vma->vm_ops = &vm_ops_oa;
>>+ vm_open_oa(vma);
>>+
>>+ return 0;
>>+}
>> static const struct file_operations fops = {
>> .owner = THIS_MODULE,
>>@@ -3332,6 +3531,7 @@ static const struct file_operations fops = {
>> * to handle 32bits compatibility.
>> */
>> .compat_ioctl = i915_perf_ioctl,
>>+ .mmap = i915_perf_mmap,
>> };
>>@@ -4260,6 +4460,7 @@ void i915_perf_init(struct drm_i915_private *i915)
>> perf->ops.oa_disable = gen7_oa_disable;
>> perf->ops.read = gen7_oa_read;
>> perf->ops.oa_hw_tail_read = gen7_oa_hw_tail_read;
>>+ perf->ops.oa_hw_head_read = gen7_oa_hw_head_read;
>> perf->oa_formats = hsw_oa_formats;
>> } else if (HAS_LOGICAL_RING_CONTEXTS(i915)) {
>>@@ -4291,6 +4492,7 @@ void i915_perf_init(struct drm_i915_private *i915)
>> perf->ops.enable_metric_set = gen8_enable_metric_set;
>> perf->ops.disable_metric_set = gen8_disable_metric_set;
>> perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
>>+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
>> if (IS_GEN(i915, 8)) {
>> perf->ctx_oactxctrl_offset = 0x120;
>>@@ -4318,6 +4520,7 @@ void i915_perf_init(struct drm_i915_private *i915)
>> perf->ops.enable_metric_set = gen8_enable_metric_set;
>> perf->ops.disable_metric_set = gen10_disable_metric_set;
>> perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
>>+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
>> if (IS_GEN(i915, 10)) {
>> perf->ctx_oactxctrl_offset = 0x128;
>>@@ -4342,6 +4545,7 @@ void i915_perf_init(struct drm_i915_private *i915)
>> perf->ops.enable_metric_set = gen12_enable_metric_set;
>> perf->ops.disable_metric_set = gen12_disable_metric_set;
>> perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
>>+ perf->ops.oa_hw_head_read = gen12_oa_hw_head_read;
>> perf->ctx_flexeu0_offset = 0;
>> perf->ctx_oactxctrl_offset = 0x144;
>>@@ -4456,8 +4660,11 @@ int i915_perf_ioctl_version(void)
>> *
>> * - OA buffer head/tail/status/buffer registers for read only
>> * - OA counters A18, A19, A20 for read/write
>>+ *
>>+ * 8: Added an option to map oa buffer at umd driver level and trigger
>>+ * oa reports within oa buffer from command buffer.
>> */
>>- return 7;
>>+ return 8;
>> }
>> #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
>>diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
>>index a36a455ae336..2efbe35c5fa9 100644
>>--- a/drivers/gpu/drm/i915/i915_perf_types.h
>>+++ b/drivers/gpu/drm/i915/i915_perf_types.h
>>@@ -311,6 +311,18 @@ struct i915_perf_stream {
>> * buffer should be checked for available data.
>> */
>> u64 poll_oa_period;
>>+
>>+ /**
>>+ * @closed: Open or closed state of the stream.
>>+ * True if stream is closed.
>>+ */
>>+ bool closed;
>>+
>>+ /**
>>+ * @refcount: References to the mapped OA buffer managed by this
>>+ * stream.
>>+ */
>>+ struct kref refcount;
>> };
>> /**
>>@@ -377,6 +389,11 @@ struct i915_oa_ops {
>> * generations.
>> */
>> u32 (*oa_hw_tail_read)(struct i915_perf_stream *stream);
>>+
>>+ /**
>>+ * @oa_hw_head_read: read the OA head pointer register
>>+ */
>>+ u32 (*oa_hw_head_read)(struct i915_perf_stream *stream);
>> };
>> struct i915_perf {
>>diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
>>index 00546062e023..2042f6339182 100644
>>--- a/include/uapi/drm/i915_drm.h
>>+++ b/include/uapi/drm/i915_drm.h
>>@@ -2048,6 +2048,38 @@ struct drm_i915_perf_open_param {
>> */
>> #define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
>>+/**
>>+ * Returns OA buffer properties to be used with mmap.
>>+ *
>>+ * This ioctl is available in perf revision 8.
>>+ */
>>+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IO('i', 0x3)
>>+
>>+/**
>>+ * OA buffer size and offset.
>>+ */
>>+struct drm_i915_perf_oa_buffer_info {
>>+ __u32 size;
>>+ __u32 offset;
>>+ __u64 reserved[4];
>>+};
>>+
>>+/**
>>+ * Returns current position of OA buffer head and tail.
>>+ *
>>+ * This ioctl is available in perf revision 8.
>>+ */
>>+#define I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL _IO('i', 0x4)
>>+
>>+/**
>>+ * OA buffer head and tail.
>>+ */
>>+struct drm_i915_perf_oa_buffer_head_tail {
>>+ __u32 head;
>>+ __u32 tail;
>>+ __u64 reserved[4];
>>+};
>>+
>> /**
>> * Common to all i915 perf records
>> */
>
>
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^ permalink raw reply [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-08-20 18:01 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-08-20 18:02 ` Umesh Nerlige Ramappa
0 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-08-20 18:02 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is
mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
v4: Call kref_put on closing perf fd (Chris)
v5:
- Strip access to OA buffer from unprivileged child of a privileged
parent. Use VM_DONTCOPY
- Enforce MAP_PRIVATE by checking for VM_MAYSHARE
v6:
(Chris)
- Use len of -1 in unmap_mapping_range
- Don't use stream->oa_buffer.vma->obj in vm_fault_oa
- Use kernel block comment style
- do_mmap gets a reference to the file and puts it in do_munmap, so
no need to maintain a reference to i915_perf_stream. Hence, remove
vm_open/vm_close and stream->closed hooks/checks.
(Umesh)
- Do not allow mmap if SAMPLE_OA_REPORT is not set during
i915_perf_open_ioctl.
- Drop ioctl returning head/tail since this information is already
whitelisted. Remove hooks to read head register.
v7: (Chris)
- unmap before destroy
- change ioctl argument struct
v8: Documentation and more checks (Chris)
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 126 ++++++++++++++++++++++-
include/uapi/drm/i915_drm.h | 33 ++++++
4 files changed, 161 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 562154d3fd49..4335a12265fc 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -3265,6 +3267,44 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @cmd: ioctl command
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned int cmd,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (_IOC_SIZE(cmd) != sizeof(info))
+ return -EINVAL;
+
+ if (copy_from_user(&info, output, sizeof(info)))
+ return -EFAULT;
+
+ if (info.type || info.flags || info.rsvd)
+ return -EINVAL;
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3290,6 +3330,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, cmd, arg);
}
return -EINVAL;
@@ -3361,6 +3403,14 @@ static int i915_perf_release(struct inode *inode, struct file *file)
struct i915_perf_stream *stream = file->private_data;
struct i915_perf *perf = stream->perf;
+ /*
+ * User could have multiple vmas from multiple mmaps. We want to zap
+ * them all here. Note that a fresh fault cannot occur as the mmap holds
+ * a reference to the stream via the vma->vm_file, so before user's
+ * munmap, the stream cannot be destroyed.
+ */
+ unmap_mapping_range(file->f_mapping, 0, -1, 1);
+
mutex_lock(&perf->lock);
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
@@ -3371,6 +3421,75 @@ static int i915_perf_release(struct inode *inode, struct file *file)
return 0;
}
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ int err;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ stream->oa_buffer.vma->pages->sgl, -1);
+
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .fault = vm_fault_oa,
+};
+
+static int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ /* mmap-ing OA buffer to user space MUST absolutely be privileged */
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ /*
+ * A non-zero offset ensures that we are mapping the right object. Also
+ * leaves room for future objects added to this implementation.
+ */
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (!(stream->sample_flags & SAMPLE_OA_REPORT))
+ return -EINVAL;
+
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ /*
+ * Only support VM_READ. Enforce MAP_PRIVATE by checking for
+ * VM_MAYSHARE.
+ */
+ if (vma->vm_flags & (VM_WRITE | VM_EXEC |
+ VM_SHARED | VM_MAYSHARE))
+ return -EINVAL;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
+
+ /*
+ * If the privileged parent forks and child drops root
+ * privilege, we do not want the child to retain access to the
+ * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
+ * cases.
+ */
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
+ VM_DONTDUMP | VM_DONTCOPY;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3383,6 +3502,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4527,8 +4647,12 @@ int i915_perf_ioctl_version(void)
*
* - OA buffer head/tail/status/buffer registers for read only
* - OA counters A18, A19, A20 for read/write
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer. See
+ * I915_PERF_IOCTL_GET_OA_BUFFER_INFO.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index fa1f3d62f9a6..cc1702ddc859 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2101,6 +2101,39 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IOWR('i', 0x3, struct drm_i915_perf_oa_buffer_info)
+
+/**
+ * OA buffer size and offset.
+ *
+ * OA output buffer
+ * type: 0
+ * flags: mbz
+ *
+ * After querying the info, pass (size,offset) to mmap(),
+ *
+ * mmap(0, info.size, PROT_READ, MAP_PRIVATE, perf_fd, info.offset).
+ *
+ * Note that only a private (not shared between processes, or across fork())
+ * read-only mmapping is allowed.
+ *
+ * Userspace must treat the incoming data as tainted, but it conforms to the OA
+ * format as specified by user config. The buffer provides reports that have
+ * OA counters - A, B and C.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 type; /* in */
+ __u32 flags; /* in */
+ __u64 size; /* out */
+ __u64 offset; /* out */
+ __u64 rsvd; /* mbz */
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-08-04 17:11 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-08-04 17:11 ` Umesh Nerlige Ramappa
0 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-08-04 17:11 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is
mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
v4: Call kref_put on closing perf fd (Chris)
v5:
- Strip access to OA buffer from unprivileged child of a privileged
parent. Use VM_DONTCOPY
- Enforce MAP_PRIVATE by checking for VM_MAYSHARE
v6:
(Chris)
- Use len of -1 in unmap_mapping_range
- Don't use stream->oa_buffer.vma->obj in vm_fault_oa
- Use kernel block comment style
- do_mmap gets a reference to the file and puts it in do_munmap, so
no need to maintain a reference to i915_perf_stream. Hence, remove
vm_open/vm_close and stream->closed hooks/checks.
(Umesh)
- Do not allow mmap if SAMPLE_OA_REPORT is not set during
i915_perf_open_ioctl.
- Drop ioctl returning head/tail since this information is already
whitelisted. Remove hooks to read head register.
v7: (Chris)
- unmap before destroy
- change ioctl argument struct
v8: Documentation and more checks (Chris)
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 125 ++++++++++++++++++++++-
include/uapi/drm/i915_drm.h | 33 ++++++
4 files changed, 160 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 562154d3fd49..e2b02a9a4645 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -3265,6 +3267,43 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned int cmd,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (_IOC_SIZE(cmd) != sizeof(info))
+ return -EINVAL;
+
+ if (copy_from_user(&info, output, sizeof(info)))
+ return -EFAULT;
+
+ if (info.type || info.flags || info.rsvd)
+ return -EINVAL;
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3290,6 +3329,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, cmd, arg);
}
return -EINVAL;
@@ -3361,6 +3402,14 @@ static int i915_perf_release(struct inode *inode, struct file *file)
struct i915_perf_stream *stream = file->private_data;
struct i915_perf *perf = stream->perf;
+ /*
+ * User could have multiple vmas from multiple mmaps. We want to zap
+ * them all here. Note that a fresh fault cannot occur as the mmap holds
+ * a reference to the stream via the vma->vm_file, so before user's
+ * munmap, the stream cannot be destroyed.
+ */
+ unmap_mapping_range(file->f_mapping, 0, -1, 1);
+
mutex_lock(&perf->lock);
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
@@ -3371,6 +3420,75 @@ static int i915_perf_release(struct inode *inode, struct file *file)
return 0;
}
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ int err;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ stream->oa_buffer.vma->pages->sgl, -1);
+
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .fault = vm_fault_oa,
+};
+
+static int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ /* mmap-ing OA buffer to user space MUST absolutely be privileged */
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ /*
+ * A non-zero offset ensures that we are mapping the right object. Also
+ * leaves room for future objects added to this implementation.
+ */
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (!(stream->sample_flags & SAMPLE_OA_REPORT))
+ return -EINVAL;
+
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ /*
+ * Only support VM_READ. Enforce MAP_PRIVATE by checking for
+ * VM_MAYSHARE.
+ */
+ if (vma->vm_flags & (VM_WRITE | VM_EXEC |
+ VM_SHARED | VM_MAYSHARE))
+ return -EINVAL;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
+
+ /*
+ * If the privileged parent forks and child drops root
+ * privilege, we do not want the child to retain access to the
+ * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
+ * cases.
+ */
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
+ VM_DONTDUMP | VM_DONTCOPY;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3383,6 +3501,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4527,8 +4646,12 @@ int i915_perf_ioctl_version(void)
*
* - OA buffer head/tail/status/buffer registers for read only
* - OA counters A18, A19, A20 for read/write
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer. See
+ * I915_PERF_IOCTL_GET_OA_BUFFER_INFO.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..5a1cd8d2f6b0 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,39 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IOWR('i', 0x3, struct drm_i915_perf_oa_buffer_info)
+
+/**
+ * OA buffer size and offset.
+ *
+ * OA output buffer
+ * type: 0
+ * flags: mbz
+ *
+ * After querying the info, pass (size,offset) to mmap(),
+ *
+ * mmap(0, info.size, PROT_READ, MAP_PRIVATE, perf_fd, info.offset).
+ *
+ * Note that only a private (not shared between processes, or across fork())
+ * read-only mmapping is allowed.
+ *
+ * Userspace must treat the incoming data as tainted, but it conforms to the OA
+ * format as specified by user config. The buffer provides reports that have
+ * OA counters - A, B and C.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 type; /* in */
+ __u32 flags; /* in */
+ __u64 size; /* out */
+ __u64 offset; /* out */
+ __u64 rsvd; /* mbz */
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-31 23:58 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-07-31 23:58 ` Umesh Nerlige Ramappa
0 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-31 23:58 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is
mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
v4: Call kref_put on closing perf fd (Chris)
v5:
- Strip access to OA buffer from unprivileged child of a privileged
parent. Use VM_DONTCOPY
- Enforce MAP_PRIVATE by checking for VM_MAYSHARE
v6:
(Chris)
- Use len of -1 in unmap_mapping_range
- Don't use stream->oa_buffer.vma->obj in vm_fault_oa
- Use kernel block comment style
- do_mmap gets a reference to the file and puts it in do_munmap, so
no need to maintain a reference to i915_perf_stream. Hence, remove
vm_open/vm_close and stream->closed hooks/checks.
(Umesh)
- Do not allow mmap if SAMPLE_OA_REPORT is not set during
i915_perf_open_ioctl.
- Drop ioctl returning head/tail since this information is already
whitelisted. Remove hooks to read head register.
v7: (Chris)
- unmap before destroy
- change ioctl argument struct
v8: Documentation and more checks (Chris)
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 125 ++++++++++++++++++++++-
include/uapi/drm/i915_drm.h | 33 ++++++
4 files changed, 160 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 562154d3fd49..e2b02a9a4645 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -3265,6 +3267,43 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned int cmd,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (_IOC_SIZE(cmd) != sizeof(info))
+ return -EINVAL;
+
+ if (copy_from_user(&info, output, sizeof(info)))
+ return -EFAULT;
+
+ if (info.type || info.flags || info.rsvd)
+ return -EINVAL;
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3290,6 +3329,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, cmd, arg);
}
return -EINVAL;
@@ -3361,6 +3402,14 @@ static int i915_perf_release(struct inode *inode, struct file *file)
struct i915_perf_stream *stream = file->private_data;
struct i915_perf *perf = stream->perf;
+ /*
+ * User could have multiple vmas from multiple mmaps. We want to zap
+ * them all here. Note that a fresh fault cannot occur as the mmap holds
+ * a reference to the stream via the vma->vm_file, so before user's
+ * munmap, the stream cannot be destroyed.
+ */
+ unmap_mapping_range(file->f_mapping, 0, -1, 1);
+
mutex_lock(&perf->lock);
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
@@ -3371,6 +3420,75 @@ static int i915_perf_release(struct inode *inode, struct file *file)
return 0;
}
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ int err;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ stream->oa_buffer.vma->pages->sgl, -1);
+
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .fault = vm_fault_oa,
+};
+
+static int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ /* mmap-ing OA buffer to user space MUST absolutely be privileged */
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ /*
+ * A non-zero offset ensures that we are mapping the right object. Also
+ * leaves room for future objects added to this implementation.
+ */
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (!(stream->sample_flags & SAMPLE_OA_REPORT))
+ return -EINVAL;
+
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ /*
+ * Only support VM_READ. Enforce MAP_PRIVATE by checking for
+ * VM_MAYSHARE.
+ */
+ if (vma->vm_flags & (VM_WRITE | VM_EXEC |
+ VM_SHARED | VM_MAYSHARE))
+ return -EINVAL;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
+
+ /*
+ * If the privileged parent forks and child drops root
+ * privilege, we do not want the child to retain access to the
+ * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
+ * cases.
+ */
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
+ VM_DONTDUMP | VM_DONTCOPY;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3383,6 +3501,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4527,8 +4646,12 @@ int i915_perf_ioctl_version(void)
*
* - OA buffer head/tail/status/buffer registers for read only
* - OA counters A18, A19, A20 for read/write
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer. See
+ * I915_PERF_IOCTL_GET_OA_BUFFER_INFO.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..5a1cd8d2f6b0 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,39 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IOWR('i', 0x3, struct drm_i915_perf_oa_buffer_info)
+
+/**
+ * OA buffer size and offset.
+ *
+ * OA output buffer
+ * type: 0
+ * flags: mbz
+ *
+ * After querying the info, pass (size,offset) to mmap(),
+ *
+ * mmap(0, info.size, PROT_READ, MAP_PRIVATE, perf_fd, info.offset).
+ *
+ * Note that only a private (not shared between processes, or across fork())
+ * read-only mmapping is allowed.
+ *
+ * Userspace must treat the incoming data as tainted, but it conforms to the OA
+ * format as specified by user config. The buffer provides reports that have
+ * OA counters - A, B and C.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 type; /* in */
+ __u32 flags; /* in */
+ __u64 size; /* out */
+ __u64 offset; /* out */
+ __u64 rsvd; /* mbz */
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
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^ permalink raw reply related [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-31 14:46 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
@ 2020-07-31 14:55 ` Chris Wilson
0 siblings, 0 replies; 33+ messages in thread
From: Chris Wilson @ 2020-07-31 14:55 UTC (permalink / raw)
To: Umesh Nerlige Ramappa, intel-gfx
Quoting Umesh Nerlige Ramappa (2020-07-31 15:46:43)
> i915 used to support time based sampling mode which is good for overall
> system monitoring, but is not enough for query mode used to measure a
> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
> implementation for query, but Gen12+ requires a new approach for query
> based on triggered reports within oa buffer.
>
> Triggering reports into the OA buffer is achieved by writing into a
> a trigger register. Optionally an unused counter/register is set with a
> marker value such that a triggered report can be identified in the OA
> buffer. Reports are usually triggered at the start and end of work that
> is measured.
>
> Since OA buffer is large and queries can be frequent, an efficient way
> to look for triggered reports is required. By knowing the current head
> and tail offsets into the OA buffer, it is easier to determine the
> locality of the reports of interest.
>
> Current perf OA interface does not expose head/tail information to the
> user and it filters out invalid reports before sending data to user.
> Also considering limited size of user buffer used during a query,
> creating a 1:1 copy of the OA buffer at the user space added undesired
> complexity.
>
> The solution was to map the OA buffer to user space provided
>
> (1) that it is accessed from a privileged user.
> (2) OA report filtering is not used.
>
> These 2 conditions would satisfy the safety criteria that the current
> perf interface addresses.
>
> To enable the query:
> - Add an ioctl to expose head and tail to the user
> - Add an ioctl to return size and offset of the OA buffer
> - Map the OA buffer to the user space
>
> v2:
> - Improve commit message (Chris)
> - Do not mmap based on gem object filp. Instead, use perf_fd and support
> mmap syscall (Chris)
> - Pass non-zero offset in mmap to enforce the right object is
> mapped (Chris)
> - Do not expose gpu_address (Chris)
> - Verify start and length of vma for page alignment (Lionel)
> - Move SQNTL config out (Lionel)
>
> v3: (Chris)
> - Omit redundant checks
> - Return VM_FAULT_SIGBUS is old stream is closed
> - Maintain reference counts to stream in vm_open and vm_close
> - Use switch to identify object to be mapped
>
> v4: Call kref_put on closing perf fd (Chris)
> v5:
> - Strip access to OA buffer from unprivileged child of a privileged
> parent. Use VM_DONTCOPY
> - Enforce MAP_PRIVATE by checking for VM_MAYSHARE
>
> v6:
> (Chris)
> - Use len of -1 in unmap_mapping_range
> - Don't use stream->oa_buffer.vma->obj in vm_fault_oa
> - Use kernel block comment style
> - do_mmap gets a reference to the file and puts it in do_munmap, so
> no need to maintain a reference to i915_perf_stream. Hence, remove
> vm_open/vm_close and stream->closed hooks/checks.
> (Umesh)
> - Do not allow mmap if SAMPLE_OA_REPORT is not set during
> i915_perf_open_ioctl.
> - Drop ioctl returning head/tail since this information is already
> whitelisted. Remove hooks to read head register.
>
> v7: (Chris)
> - unmap before destroy
> - change ioctl argument struct
>
> v8: Documentation and more checks (Chris)
>
> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> ---
> +#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
> +
> +/**
> + * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
> + * @stream: i915 perf stream
> + * @arg: pointer to oa buffer info filled by this function.
> + */
> +static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
> + unsigned int cmd,
> + unsigned long arg)
> +{
> + struct drm_i915_perf_oa_buffer_info info;
> + void __user *output = (void __user *)arg;
> +
> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
> + DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
> + return -EACCES;
> + }
> +
> + if (_IOC_SIZE(cmd) != sizeof(info))
> + return -EINVAL;
For total pedantry, we could check cmd & (IOC_IN | IOC_OUT) as well :)
> +
> + if (copy_from_user(&info, output, sizeof(info)))
> + return -EFAULT;
> +
> + if (info.type || info.flags || info.rsvd)
> + return -EINVAL;
> +
> + info.size = stream->oa_buffer.vma->size;
> + info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
> +
> + if (copy_to_user(output, &info, sizeof(info)))
> + return -EFAULT;
> +
> + return 0;
> +}
> +
> /**
> * i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
> * @stream: An i915 perf stream
> @@ -3290,6 +3329,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
> return 0;
> case I915_PERF_IOCTL_CONFIG:
> return i915_perf_config_locked(stream, arg);
> + case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
> + return i915_perf_oa_buffer_info_locked(stream, cmd, arg);
> }
>
> return -EINVAL;
> @@ -3361,6 +3402,14 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> struct i915_perf_stream *stream = file->private_data;
> struct i915_perf *perf = stream->perf;
>
> + /*
> + * User could have multiple vmas from multiple mmaps. We want to zap
> + * them all here. Note that a fresh fault cannot occur as the mmap holds
> + * a reference to the stream via the vma->vm_file, so before user's
> + * munmap, the stream cannot be destroyed.
> + */
> + unmap_mapping_range(file->f_mapping, 0, -1, 1);
> +
> mutex_lock(&perf->lock);
> i915_perf_destroy_locked(stream);
> mutex_unlock(&perf->lock);
> @@ -3371,6 +3420,75 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> return 0;
> }
>
> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
> +{
> + struct vm_area_struct *vma = vmf->vma;
> + struct i915_perf_stream *stream = vma->vm_private_data;
> + int err;
> +
> + err = remap_io_sg(vma,
> + vma->vm_start, vma->vm_end - vma->vm_start,
> + stream->oa_buffer.vma->pages->sgl, -1);
> +
> + return i915_error_to_vmf_fault(err);
> +}
> +
> +static const struct vm_operations_struct vm_ops_oa = {
> + .fault = vm_fault_oa,
> +};
> +
> +static int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
> +{
> + struct i915_perf_stream *stream = file->private_data;
> +
> + /* mmap-ing OA buffer to user space MUST absolutely be privileged */
> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
> + DRM_DEBUG("Insufficient privileges to map OA buffer\n");
> + return -EACCES;
> + }
> +
> + switch (vma->vm_pgoff) {
> + /*
> + * A non-zero offset ensures that we are mapping the right object. Also
> + * leaves room for future objects added to this implementation.
> + */
> + case I915_PERF_OA_BUFFER_MMAP_OFFSET:
> + if (!(stream->sample_flags & SAMPLE_OA_REPORT))
> + return -EINVAL;
> +
> + if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
> + return -EINVAL;
> +
> + /*
> + * Only support VM_READ. Enforce MAP_PRIVATE by checking for
> + * VM_MAYSHARE.
> + */
> + if (vma->vm_flags & (VM_WRITE | VM_EXEC |
> + VM_SHARED | VM_MAYSHARE))
> + return -EINVAL;
> +
> + vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
> +
> + /*
> + * If the privileged parent forks and child drops root
> + * privilege, we do not want the child to retain access to the
> + * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
> + * cases.
> + */
> + vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
> + VM_DONTDUMP | VM_DONTCOPY;
> + break;
> +
> + default:
> + return -EINVAL;
> + }
> +
> + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
> + vma->vm_private_data = stream;
> + vma->vm_ops = &vm_ops_oa;
> +
> + return 0;
> +}
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris
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^ permalink raw reply [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-31 14:46 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-07-31 14:46 ` Umesh Nerlige Ramappa
2020-07-31 14:55 ` Chris Wilson
0 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-31 14:46 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is
mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
v4: Call kref_put on closing perf fd (Chris)
v5:
- Strip access to OA buffer from unprivileged child of a privileged
parent. Use VM_DONTCOPY
- Enforce MAP_PRIVATE by checking for VM_MAYSHARE
v6:
(Chris)
- Use len of -1 in unmap_mapping_range
- Don't use stream->oa_buffer.vma->obj in vm_fault_oa
- Use kernel block comment style
- do_mmap gets a reference to the file and puts it in do_munmap, so
no need to maintain a reference to i915_perf_stream. Hence, remove
vm_open/vm_close and stream->closed hooks/checks.
(Umesh)
- Do not allow mmap if SAMPLE_OA_REPORT is not set during
i915_perf_open_ioctl.
- Drop ioctl returning head/tail since this information is already
whitelisted. Remove hooks to read head register.
v7: (Chris)
- unmap before destroy
- change ioctl argument struct
v8: Documentation and more checks (Chris)
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 125 ++++++++++++++++++++++-
include/uapi/drm/i915_drm.h | 33 ++++++
4 files changed, 160 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 562154d3fd49..8af7cc2d523a 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -3265,6 +3267,43 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned int cmd,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (_IOC_SIZE(cmd) != sizeof(info))
+ return -EINVAL;
+
+ if (copy_from_user(&info, output, sizeof(info)))
+ return -EFAULT;
+
+ if (info.type || info.flags || info.rsvd)
+ return -EINVAL;
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3290,6 +3329,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, cmd, arg);
}
return -EINVAL;
@@ -3361,6 +3402,14 @@ static int i915_perf_release(struct inode *inode, struct file *file)
struct i915_perf_stream *stream = file->private_data;
struct i915_perf *perf = stream->perf;
+ /*
+ * User could have multiple vmas from multiple mmaps. We want to zap
+ * them all here. Note that a fresh fault cannot occur as the mmap holds
+ * a reference to the stream via the vma->vm_file, so before user's
+ * munmap, the stream cannot be destroyed.
+ */
+ unmap_mapping_range(file->f_mapping, 0, -1, 1);
+
mutex_lock(&perf->lock);
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
@@ -3371,6 +3420,75 @@ static int i915_perf_release(struct inode *inode, struct file *file)
return 0;
}
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ int err;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ stream->oa_buffer.vma->pages->sgl, -1);
+
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .fault = vm_fault_oa,
+};
+
+static int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ /* mmap-ing OA buffer to user space MUST absolutely be privileged */
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ /*
+ * A non-zero offset ensures that we are mapping the right object. Also
+ * leaves room for future objects added to this implementation.
+ */
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (!(stream->sample_flags & SAMPLE_OA_REPORT))
+ return -EINVAL;
+
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ /*
+ * Only support VM_READ. Enforce MAP_PRIVATE by checking for
+ * VM_MAYSHARE.
+ */
+ if (vma->vm_flags & (VM_WRITE | VM_EXEC |
+ VM_SHARED | VM_MAYSHARE))
+ return -EINVAL;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
+
+ /*
+ * If the privileged parent forks and child drops root
+ * privilege, we do not want the child to retain access to the
+ * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
+ * cases.
+ */
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
+ VM_DONTDUMP | VM_DONTCOPY;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3383,6 +3501,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4527,8 +4646,12 @@ int i915_perf_ioctl_version(void)
*
* - OA buffer head/tail/status/buffer registers for read only
* - OA counters A18, A19, A20 for read/write
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer. See
+ * I915_PERF_IOCTL_GET_OA_BUFFER_INFO.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..16e497461951 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,39 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IOWR('i', 0x3, struct drm_i915_perf_oa_buffer_info)
+
+/**
+ * OA buffer size and offset.
+ *
+ * OA output buffer
+ * type: 0
+ * flags: mbz
+ *
+ * After querying the info, pass (size,offset) to mmap(),
+ *
+ * mmap(0, info.size, PROT_READ, MAP_PRIVATE, perf_fd, info.offset).
+ *
+ * Note that only a private (not shared between processes, or across fork())
+ * read-only mmapping is allowed.
+ *
+ * Userspace must treat the incoming data as tainted, but it conforms to the OA
+ * format as specified by user config. The buffer provides reports that have
+ * OA counters - A, B and C.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 type; /* in */
+ __u32 flags; /* in */
+ __u64 size; /* out */
+ __u64 offset; /* out */
+ __u64 rsvd; /* mbz */
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
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^ permalink raw reply related [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-31 6:07 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
@ 2020-07-31 9:35 ` Chris Wilson
0 siblings, 0 replies; 33+ messages in thread
From: Chris Wilson @ 2020-07-31 9:35 UTC (permalink / raw)
To: Umesh Nerlige Ramappa, intel-gfx
Quoting Umesh Nerlige Ramappa (2020-07-31 07:07:23)
> i915 used to support time based sampling mode which is good for overall
> system monitoring, but is not enough for query mode used to measure a
> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
> implementation for query, but Gen12+ requires a new approach for query
> based on triggered reports within oa buffer.
>
> Triggering reports into the OA buffer is achieved by writing into a
> a trigger register. Optionally an unused counter/register is set with a
> marker value such that a triggered report can be identified in the OA
> buffer. Reports are usually triggered at the start and end of work that
> is measured.
>
> Since OA buffer is large and queries can be frequent, an efficient way
> to look for triggered reports is required. By knowing the current head
> and tail offsets into the OA buffer, it is easier to determine the
> locality of the reports of interest.
>
> Current perf OA interface does not expose head/tail information to the
> user and it filters out invalid reports before sending data to user.
> Also considering limited size of user buffer used during a query,
> creating a 1:1 copy of the OA buffer at the user space added undesired
> complexity.
>
> The solution was to map the OA buffer to user space provided
>
> (1) that it is accessed from a privileged user.
> (2) OA report filtering is not used.
>
> These 2 conditions would satisfy the safety criteria that the current
> perf interface addresses.
>
> To enable the query:
> - Add an ioctl to expose head and tail to the user
> - Add an ioctl to return size and offset of the OA buffer
> - Map the OA buffer to the user space
>
> v2:
> - Improve commit message (Chris)
> - Do not mmap based on gem object filp. Instead, use perf_fd and support
> mmap syscall (Chris)
> - Pass non-zero offset in mmap to enforce the right object is
> mapped (Chris)
> - Do not expose gpu_address (Chris)
> - Verify start and length of vma for page alignment (Lionel)
> - Move SQNTL config out (Lionel)
>
> v3: (Chris)
> - Omit redundant checks
> - Return VM_FAULT_SIGBUS is old stream is closed
> - Maintain reference counts to stream in vm_open and vm_close
> - Use switch to identify object to be mapped
>
> v4: Call kref_put on closing perf fd (Chris)
> v5:
> - Strip access to OA buffer from unprivileged child of a privileged
> parent. Use VM_DONTCOPY
> - Enforce MAP_PRIVATE by checking for VM_MAYSHARE
>
> v6:
> (Chris)
> - Use len of -1 in unmap_mapping_range
> - Don't use stream->oa_buffer.vma->obj in vm_fault_oa
> - Use kernel block comment style
> - do_mmap gets a reference to the file and puts it in do_munmap, so
> no need to maintain a reference to i915_perf_stream. Hence, remove
> vm_open/vm_close and stream->closed hooks/checks.
> (Umesh)
> - Do not allow mmap if SAMPLE_OA_REPORT is not set during
> i915_perf_open_ioctl.
> - Drop ioctl returning head/tail since this information is already
> whitelisted. Remove hooks to read head register.
>
> v7: (Chris)
> - unmap before destroy
> - change ioctl argument struct
>
> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> ---
> drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
> drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
> drivers/gpu/drm/i915/i915_perf.c | 123 ++++++++++++++++++++++-
> include/uapi/drm/i915_drm.h | 18 ++++
> 4 files changed, 143 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> index b23368529a40..7c4b9b0c334b 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
> @@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
> return view;
> }
>
> -static vm_fault_t i915_error_to_vmf_fault(int err)
> +vm_fault_t i915_error_to_vmf_fault(int err)
> {
> switch (err) {
> default:
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
> index efee9e0d2508..1190a3a228ea 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
> @@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
>
> void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
>
> +vm_fault_t i915_error_to_vmf_fault(int err);
> +
> #endif
> diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
> index 8ff502719dfd..8ac7944c24b8 100644
> --- a/drivers/gpu/drm/i915/i915_perf.c
> +++ b/drivers/gpu/drm/i915/i915_perf.c
> @@ -192,10 +192,12 @@
> */
>
> #include <linux/anon_inodes.h>
> +#include <linux/mman.h>
> #include <linux/sizes.h>
> #include <linux/uuid.h>
>
> #include "gem/i915_gem_context.h"
> +#include "gem/i915_gem_mman.h"
> #include "gt/intel_engine_pm.h"
> #include "gt/intel_engine_user.h"
> #include "gt/intel_gt.h"
> @@ -3269,6 +3271,42 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
> return ret;
> }
>
> +#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
> +
> +/**
> + * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
> + * @stream: i915 perf stream
> + * @arg: pointer to oa buffer info filled by this function.
> + */
> +static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
> + unsigned long arg)
> +{
> + struct drm_i915_perf_oa_buffer_info info;
> + void __user *output = (void __user *)arg;
> +
> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
> + DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
> + return -EACCES;
> + }
> +
> + if (!output)
> + return -EINVAL;
I'd leave that for copy_from_user to return EFAULT?
But you should pass the cmd in so we can validate arg is large enough.
Otherwise we may accidentally overwrite the user's data should the
struct change.
> + if (copy_from_user(&info, output, sizeof(info)))
> + return -EFAULT;
> +
> + if (info.type || info.flags || info.rsvd)
> + return -EINVAL;
> +
> + info.size = stream->oa_buffer.vma->size;
> + info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
> +
> + if (copy_to_user(output, &info, sizeof(info)))
> + return -EFAULT;
> +
> + return 0;
> +}
> +
> /**
> * i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
> * @stream: An i915 perf stream
> @@ -3294,6 +3332,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
> return 0;
> case I915_PERF_IOCTL_CONFIG:
> return i915_perf_config_locked(stream, arg);
> + case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
> + return i915_perf_oa_buffer_info_locked(stream, arg);
> }
>
> return -EINVAL;
> @@ -3365,6 +3405,14 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> struct i915_perf_stream *stream = file->private_data;
> struct i915_perf *perf = stream->perf;
>
> + /*
> + * User could have multiple vmas from multiple mmaps. We want to zap
> + * them all here. Note that a fresh fault cannot occur as the mmap holds
> + * a reference to the stream via the vma->vm_file, so before user's
> + * munmap, the stream cannot be destroyed.
> + */
> + unmap_mapping_range(file->f_mapping, 0, -1, 1);
> +
> mutex_lock(&perf->lock);
> i915_perf_destroy_locked(stream);
> mutex_unlock(&perf->lock);
> @@ -3375,6 +3423,75 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> return 0;
> }
>
> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
> +{
> + struct vm_area_struct *vma = vmf->vma;
> + struct i915_perf_stream *stream = vma->vm_private_data;
> + int err;
> +
> + err = remap_io_sg(vma,
> + vma->vm_start, vma->vm_end - vma->vm_start,
> + stream->oa_buffer.vma->pages->sgl, -1);
> +
> + return i915_error_to_vmf_fault(err);
> +}
> +
> +static const struct vm_operations_struct vm_ops_oa = {
> + .fault = vm_fault_oa,
> +};
> +
> +int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
static int i915_perf_mmap
> +{
> + struct i915_perf_stream *stream = file->private_data;
> +
> + /* mmap-ing OA buffer to user space MUST absolutely be privileged */
> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
> + DRM_DEBUG("Insufficient privileges to map OA buffer\n");
> + return -EACCES;
> + }
> +
> + switch (vma->vm_pgoff) {
> + /*
> + * A non-zero offset ensures that we are mapping the right object. Also
> + * leaves room for future objects added to this implementation.
> + */
> + case I915_PERF_OA_BUFFER_MMAP_OFFSET:
> + if (!(stream->sample_flags & SAMPLE_OA_REPORT))
> + return -EINVAL;
> +
> + if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
> + return -EINVAL;
> +
> + /*
> + * Only support VM_READ. Enforce MAP_PRIVATE by checking for
> + * VM_MAYSHARE.
> + */
> + if (vma->vm_flags & (VM_WRITE | VM_EXEC |
> + VM_SHARED | VM_MAYSHARE))
> + return -EINVAL;
> +
> + vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
> +
> + /*
> + * If the privileged parent forks and child drops root
> + * privilege, we do not want the child to retain access to the
> + * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
> + * cases.
> + */
> + vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
> + VM_DONTDUMP | VM_DONTCOPY;
> + break;
> +
> + default:
> + return -EINVAL;
> + }
> +
> + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
> + vma->vm_private_data = stream;
> + vma->vm_ops = &vm_ops_oa;
> +
> + return 0;
> +}
>
> static const struct file_operations fops = {
> .owner = THIS_MODULE,
> @@ -3387,6 +3504,7 @@ static const struct file_operations fops = {
> * to handle 32bits compatibility.
> */
> .compat_ioctl = i915_perf_ioctl,
> + .mmap = i915_perf_mmap,
> };
>
>
> @@ -4531,8 +4649,11 @@ int i915_perf_ioctl_version(void)
> *
> * - OA buffer head/tail/status/buffer registers for read only
> * - OA counters A18, A19, A20 for read/write
> + *
> + * 8: Added an option to map oa buffer at umd driver level and trigger
> + * oa reports within oa buffer from command buffer.
Add a cross-reference?
* See I915_PERF_IOCTL_GET_OA_BUFFER_INFO
> */
> - return 7;
> + return 8;
> }
>
> #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
> diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
> index 00546062e023..35b8ed02ad25 100644
> --- a/include/uapi/drm/i915_drm.h
> +++ b/include/uapi/drm/i915_drm.h
> @@ -2048,6 +2048,24 @@ struct drm_i915_perf_open_param {
> */
> #define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
>
> +/**
> + * Returns OA buffer properties to be used with mmap.
> + *
> + * This ioctl is available in perf revision 8.
> + */
> +#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IOWR('i', 0x3, struct drm_i915_perf_oa_buffer_info)
> +
> +/**
> + * OA buffer size and offset.
Declare the available types and their limitations.
OA output buffer
type: 0
flags: mbz
After querying the info, pass (size,offset) to mmap(),
mmap(0, info.size, PROT_READ, MAP_PRIVATE, perf_fd, info.offset)
Note that only a private (not shared between processes, or across
fork()) read-only mmapping is allowed.
We probably also should mention that userspace must treat the incoming
data as tainted, but it is expected to conform to the OA format as
specified by their config. And mention the set of control registers
associated with the buffer? [At least in general terms such that one can
find the relevant information in the specs.]
> + */
> +struct drm_i915_perf_oa_buffer_info {
> + __u32 type; /* in */
> + __u32 flags; /* in */
> + __u64 size; /* out */
> + __u64 offset; /* out */
> + __u64 rsvd; /* mbz */
> +};
> +
> /**
> * Common to all i915 perf records
> */
> --
> 2.20.1
>
> _______________________________________________
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> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>
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^ permalink raw reply [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-31 6:07 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-07-31 6:07 ` Umesh Nerlige Ramappa
2020-07-31 9:35 ` Chris Wilson
0 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-31 6:07 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is
mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
v4: Call kref_put on closing perf fd (Chris)
v5:
- Strip access to OA buffer from unprivileged child of a privileged
parent. Use VM_DONTCOPY
- Enforce MAP_PRIVATE by checking for VM_MAYSHARE
v6:
(Chris)
- Use len of -1 in unmap_mapping_range
- Don't use stream->oa_buffer.vma->obj in vm_fault_oa
- Use kernel block comment style
- do_mmap gets a reference to the file and puts it in do_munmap, so
no need to maintain a reference to i915_perf_stream. Hence, remove
vm_open/vm_close and stream->closed hooks/checks.
(Umesh)
- Do not allow mmap if SAMPLE_OA_REPORT is not set during
i915_perf_open_ioctl.
- Drop ioctl returning head/tail since this information is already
whitelisted. Remove hooks to read head register.
v7: (Chris)
- unmap before destroy
- change ioctl argument struct
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 123 ++++++++++++++++++++++-
include/uapi/drm/i915_drm.h | 18 ++++
4 files changed, 143 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 8ff502719dfd..8ac7944c24b8 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -3269,6 +3271,42 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (!output)
+ return -EINVAL;
+
+ if (copy_from_user(&info, output, sizeof(info)))
+ return -EFAULT;
+
+ if (info.type || info.flags || info.rsvd)
+ return -EINVAL;
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3294,6 +3332,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, arg);
}
return -EINVAL;
@@ -3365,6 +3405,14 @@ static int i915_perf_release(struct inode *inode, struct file *file)
struct i915_perf_stream *stream = file->private_data;
struct i915_perf *perf = stream->perf;
+ /*
+ * User could have multiple vmas from multiple mmaps. We want to zap
+ * them all here. Note that a fresh fault cannot occur as the mmap holds
+ * a reference to the stream via the vma->vm_file, so before user's
+ * munmap, the stream cannot be destroyed.
+ */
+ unmap_mapping_range(file->f_mapping, 0, -1, 1);
+
mutex_lock(&perf->lock);
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
@@ -3375,6 +3423,75 @@ static int i915_perf_release(struct inode *inode, struct file *file)
return 0;
}
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ int err;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ stream->oa_buffer.vma->pages->sgl, -1);
+
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .fault = vm_fault_oa,
+};
+
+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ /* mmap-ing OA buffer to user space MUST absolutely be privileged */
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ /*
+ * A non-zero offset ensures that we are mapping the right object. Also
+ * leaves room for future objects added to this implementation.
+ */
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (!(stream->sample_flags & SAMPLE_OA_REPORT))
+ return -EINVAL;
+
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ /*
+ * Only support VM_READ. Enforce MAP_PRIVATE by checking for
+ * VM_MAYSHARE.
+ */
+ if (vma->vm_flags & (VM_WRITE | VM_EXEC |
+ VM_SHARED | VM_MAYSHARE))
+ return -EINVAL;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
+
+ /*
+ * If the privileged parent forks and child drops root
+ * privilege, we do not want the child to retain access to the
+ * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
+ * cases.
+ */
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
+ VM_DONTDUMP | VM_DONTCOPY;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3387,6 +3504,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4531,8 +4649,11 @@ int i915_perf_ioctl_version(void)
*
* - OA buffer head/tail/status/buffer registers for read only
* - OA counters A18, A19, A20 for read/write
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..35b8ed02ad25 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,24 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IOWR('i', 0x3, struct drm_i915_perf_oa_buffer_info)
+
+/**
+ * OA buffer size and offset.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 type; /* in */
+ __u32 flags; /* in */
+ __u64 size; /* out */
+ __u64 offset; /* out */
+ __u64 rsvd; /* mbz */
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
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^ permalink raw reply related [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-30 23:02 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-07-30 23:02 ` Umesh Nerlige Ramappa
0 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-30 23:02 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is
mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
v4: Call kref_put on closing perf fd (Chris)
v5:
- Strip access to OA buffer from unprivileged child of a privileged
parent. Use VM_DONTCOPY
- Enforce MAP_PRIVATE by checking for VM_MAYSHARE
v6:
(Chris)
- Use len of -1 in unmap_mapping_range
- Don't use stream->oa_buffer.vma->obj in vm_fault_oa
- Use kernel block comment style
- do_mmap gets a reference to the file and puts it in do_munmap, so
no need to maintain a reference to i915_perf_stream. Hence, remove
vm_open/vm_close and stream->closed hooks/checks.
(Umesh)
- Do not allow mmap if SAMPLE_OA_REPORT is not set during
i915_perf_open_ioctl.
- Drop ioctl returning head/tail since this information is already
whitelisted. Remove hooks to read head register.
v7: (Chris)
- unmap before destroy
- change ioctl argument struct
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 123 ++++++++++++++++++++++-
include/uapi/drm/i915_drm.h | 18 ++++
4 files changed, 143 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 8ff502719dfd..8ac7944c24b8 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -3269,6 +3271,42 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (!output)
+ return -EINVAL;
+
+ if (copy_from_user(&info, output, sizeof(info)))
+ return -EFAULT;
+
+ if (info.type || info.flags || info.rsvd)
+ return -EINVAL;
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3294,6 +3332,8 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, arg);
}
return -EINVAL;
@@ -3365,6 +3405,14 @@ static int i915_perf_release(struct inode *inode, struct file *file)
struct i915_perf_stream *stream = file->private_data;
struct i915_perf *perf = stream->perf;
+ /*
+ * User could have multiple vmas from multiple mmaps. We want to zap
+ * them all here. Note that a fresh fault cannot occur as the mmap holds
+ * a reference to the stream via the vma->vm_file, so before user's
+ * munmap, the stream cannot be destroyed.
+ */
+ unmap_mapping_range(file->f_mapping, 0, -1, 1);
+
mutex_lock(&perf->lock);
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
@@ -3375,6 +3423,75 @@ static int i915_perf_release(struct inode *inode, struct file *file)
return 0;
}
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ int err;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ stream->oa_buffer.vma->pages->sgl, -1);
+
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .fault = vm_fault_oa,
+};
+
+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ /* mmap-ing OA buffer to user space MUST absolutely be privileged */
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ /*
+ * A non-zero offset ensures that we are mapping the right object. Also
+ * leaves room for future objects added to this implementation.
+ */
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (!(stream->sample_flags & SAMPLE_OA_REPORT))
+ return -EINVAL;
+
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ /*
+ * Only support VM_READ. Enforce MAP_PRIVATE by checking for
+ * VM_MAYSHARE.
+ */
+ if (vma->vm_flags & (VM_WRITE | VM_EXEC |
+ VM_SHARED | VM_MAYSHARE))
+ return -EINVAL;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
+
+ /*
+ * If the privileged parent forks and child drops root
+ * privilege, we do not want the child to retain access to the
+ * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
+ * cases.
+ */
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
+ VM_DONTDUMP | VM_DONTCOPY;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3387,6 +3504,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4531,8 +4649,11 @@ int i915_perf_ioctl_version(void)
*
* - OA buffer head/tail/status/buffer registers for read only
* - OA counters A18, A19, A20 for read/write
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..35b8ed02ad25 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,24 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IOWR('i', 0x3, struct drm_i915_perf_oa_buffer_info)
+
+/**
+ * OA buffer size and offset.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 type; /* in */
+ __u32 flags; /* in */
+ __u64 size; /* out */
+ __u64 offset; /* out */
+ __u64 rsvd; /* mbz */
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 19:46 ` Chris Wilson
@ 2020-07-24 22:05 ` Umesh Nerlige Ramappa
0 siblings, 0 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-24 22:05 UTC (permalink / raw)
To: Chris Wilson; +Cc: intel-gfx
On Fri, Jul 24, 2020 at 08:46:16PM +0100, Chris Wilson wrote:
>Quoting Umesh Nerlige Ramappa (2020-07-24 20:35:11)
>> I agree, but strangely, with mmap sequence below, I don't see
>> i915_perf_release() called at all. So destroy() is not called.
>>
>> perf_fd = i915_perf_open_ioctl()
>> mmap(..., perf_fd...)
>> close(perf_fd)
>> delay for a few seconds.
>>
>> If I call munmap() after the close(), I see i915_perf_release() ->
>> destroy() -> unmap_mapping_range()
>
>Hmm, vma->vm_file is pointing to the perf-fd. Ah, that's a big
>difference to what I'm used to. So all the references are handled for
>you by the correct vma->vm_file, and you don't need the
>vm_open/vm_close, the kref or the closed. Sorry.
no worries at all. This is all new for me, so I appreciate all your
prompt guidance that helped me look into this implementation in detail.
Thanks,
Umesh
>-Chris
_______________________________________________
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https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 19:35 ` Umesh Nerlige Ramappa
@ 2020-07-24 19:46 ` Chris Wilson
2020-07-24 22:05 ` Umesh Nerlige Ramappa
0 siblings, 1 reply; 33+ messages in thread
From: Chris Wilson @ 2020-07-24 19:46 UTC (permalink / raw)
To: Umesh Nerlige Ramappa; +Cc: intel-gfx
Quoting Umesh Nerlige Ramappa (2020-07-24 20:35:11)
> I agree, but strangely, with mmap sequence below, I don't see
> i915_perf_release() called at all. So destroy() is not called.
>
> perf_fd = i915_perf_open_ioctl()
> mmap(..., perf_fd...)
> close(perf_fd)
> delay for a few seconds.
>
> If I call munmap() after the close(), I see i915_perf_release() ->
> destroy() -> unmap_mapping_range()
Hmm, vma->vm_file is pointing to the perf-fd. Ah, that's a big
difference to what I'm used to. So all the references are handled for
you by the correct vma->vm_file, and you don't need the
vm_open/vm_close, the kref or the closed. Sorry.
-Chris
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^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 18:55 ` Chris Wilson
@ 2020-07-24 19:35 ` Umesh Nerlige Ramappa
2020-07-24 19:46 ` Chris Wilson
0 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-24 19:35 UTC (permalink / raw)
To: Chris Wilson; +Cc: intel-gfx
On Fri, Jul 24, 2020 at 07:55:06PM +0100, Chris Wilson wrote:
>Quoting Umesh Nerlige Ramappa (2020-07-24 19:47:37)
>> On Fri, Jul 24, 2020 at 05:34:11PM +0100, Chris Wilson wrote:
>> >Quoting Umesh Nerlige Ramappa (2020-07-24 17:29:56)
>> >> On Fri, Jul 24, 2020 at 01:42:33PM +0100, Chris Wilson wrote:
>> >> >Quoting Umesh Nerlige Ramappa (2020-07-24 01:19:01)
>> >> >> From: Piotr Maciejewski <piotr.maciejewski@intel.com>
>> >> >>
>> >> >> i915 used to support time based sampling mode which is good for overall
>> >> >> system monitoring, but is not enough for query mode used to measure a
>> >> >> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
>> >> >> implementation for query, but Gen12+ requires a new approach for query
>> >> >> based on triggered reports within oa buffer.
>> >> >>
>> >> >> Triggering reports into the OA buffer is achieved by writing into a
>> >> >> a trigger register. Optionally an unused counter/register is set with a
>> >> >> marker value such that a triggered report can be identified in the OA
>> >> >> buffer. Reports are usually triggered at the start and end of work that
>> >> >> is measured.
>> >> >>
>> >> >> Since OA buffer is large and queries can be frequent, an efficient way
>> >> >> to look for triggered reports is required. By knowing the current head
>> >> >> and tail offsets into the OA buffer, it is easier to determine the
>> >> >> locality of the reports of interest.
>> >> >>
>> >> >> Current perf OA interface does not expose head/tail information to the
>> >> >> user and it filters out invalid reports before sending data to user.
>> >> >> Also considering limited size of user buffer used during a query,
>> >> >> creating a 1:1 copy of the OA buffer at the user space added undesired
>> >> >> complexity.
>> >> >>
>> >> >> The solution was to map the OA buffer to user space provided
>> >> >>
>> >> >> (1) that it is accessed from a privileged user.
>> >> >> (2) OA report filtering is not used.
>> >> >>
>> >> >> These 2 conditions would satisfy the safety criteria that the current
>> >> >> perf interface addresses.
>> >> >>
>> >> >> To enable the query:
>> >> >> - Add an ioctl to expose head and tail to the user
>> >> >> - Add an ioctl to return size and offset of the OA buffer
>> >> >> - Map the OA buffer to the user space
>> >> >>
>> >> >> v2:
>> >> >> - Improve commit message (Chris)
>> >> >> - Do not mmap based on gem object filp. Instead, use perf_fd and support
>> >> >> mmap syscall (Chris)
>> >> >> - Pass non-zero offset in mmap to enforce the right object is
>> >> >> mapped (Chris)
>> >> >> - Do not expose gpu_address (Chris)
>> >> >> - Verify start and length of vma for page alignment (Lionel)
>> >> >> - Move SQNTL config out (Lionel)
>> >> >>
>> >> >> v3: (Chris)
>> >> >> - Omit redundant checks
>> >> >> - Return VM_FAULT_SIGBUS is old stream is closed
>> >> >> - Maintain reference counts to stream in vm_open and vm_close
>> >> >> - Use switch to identify object to be mapped
>> >> >>
>> >> >> v4: Call kref_put on closing perf fd (Chris)
>> >> >> v5:
>> >> >> - Strip access to OA buffer from unprivileged child of a privileged
>> >> >> parent. Use VM_DONTCOPY
>> >> >> - Enforce MAP_PRIVATE by checking for VM_MAYSHARE
>> >> >>
>> >> >> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
>> >> >> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
>> >> >> ---
>> >> >> @@ -3314,12 +3427,113 @@ static int i915_perf_release(struct inode *inode, struct file *file)
>> >> >> i915_perf_destroy_locked(stream);
>> >> >> mutex_unlock(&perf->lock);
>> >> >>
>> >> >> + unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
>> >> >
>> >> >You can just used unmap_mapping_range(file->f_mapping, 0, -1, 1);
>> >> >It scales with the number of vma present, so no worries, be conservative.
>> >> >(Otherwise, you need s/0/OA_BUFFER_OFFSET/.)
>> >> >
>> >> >> +
>> >> >> /* Release the reference the perf stream kept on the driver. */
>> >> >> drm_dev_put(&perf->i915->drm);
>> >> >>
>> >> >> return 0;
>> >> >> }
>> >> >>
>> >> >> +static void vm_open_oa(struct vm_area_struct *vma)
>> >> >> +{
>> >> >> + struct i915_perf_stream *stream = vma->vm_private_data;
>> >> >> +
>> >> >> + GEM_BUG_ON(!stream);
>> >> >> + perf_stream_get(stream);
>> >> >> +}
>> >> >> +
>> >> >> +static void vm_close_oa(struct vm_area_struct *vma)
>> >> >> +{
>> >> >> + struct i915_perf_stream *stream = vma->vm_private_data;
>> >> >> +
>> >> >> + GEM_BUG_ON(!stream);
>> >> >> + perf_stream_put(stream);
>> >> >> +}
>> >> >> +
>> >> >> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
>> >> >> +{
>> >> >> + struct vm_area_struct *vma = vmf->vma;
>> >> >> + struct i915_perf_stream *stream = vma->vm_private_data;
>> >> >> + struct i915_perf *perf = stream->perf;
>> >> >> + struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
>> >> >> + int err;
>> >> >> + bool closed;
>> >> >
>> >> >So vm_area_struct has a reference to the stream, that looks good now.
>> >> >But there's no reference held to the vma itself.
>> >>
>> >> How do I get a reference to the vma.
>> >
>> >That would be i915_vma_get(), but you don't need to if we control the
>> >order correctly, as then neither the PTE nor the ongoing faulthandler
>> >last longer than the i915_perf_stream
>>
>> I see that the do_mmap()->mmap_region() takes a reference to file
>>
>> vma->vm_file = get_file(file);
>
>By vma, I meant stream-oa_buffer.vma
aah, ok.
>
>> In our case this is perf_fd. do_munmap does a corresponding fput.
>>
>> so unmap_mapping_range() is never called unless both unmap() and
>> close(perf_fd) are called by user (or process terminates).
>
>The unmap_mapping_range() is called by destroy, so that should be
>independent of userspace munmap.
I agree, but strangely, with mmap sequence below, I don't see
i915_perf_release() called at all. So destroy() is not called.
perf_fd = i915_perf_open_ioctl()
mmap(..., perf_fd...)
close(perf_fd)
delay for a few seconds.
If I call munmap() after the close(), I see i915_perf_release() ->
destroy() -> unmap_mapping_range()
Thanks,
Umesh
>
>> Is that good to take care of this ordering?
>>
>> This also explains why I cannot get a VM_FAULT_SIGBUS with the IGTs.
>
>To hit the stream->close you'll need to race mmap/munmap against perf
>destroy. You may like to challenge yourself to hit it :)
>
>> >> >> + mutex_lock(&perf->lock);
>> >> >> + closed = READ_ONCE(stream->closed);
>> >> >> + mutex_unlock(&perf->lock);
>> >> >
>> >> >We do WRITE_ONCE(stream->closed, true) then invalidate all the mappings,
>> >> >so that part looks good. The invalidate is serialised with the
>> >> >vm_fault_oa, so we can just use a plain READ_ONCE(stream->closed) here
>> >> >and not worry about the perf->lock.
>> >>
>> >> will do
>> >> >
>> >> >However... I think it should close&invalidate before releasing
>> >> >stream->oa_buffer.
>> >>
>> >> will do
>> >> >
>> >> >And the read here of stream->oa_buffer should be after checking
>> >> >stream->closed.
>> >>
>> >> I don't understand. I am checking for closed before remap_io_sg.
>> >
>> >It's the
>> >
>> >struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
>> >
>> >that's before the stream->closed check. That's dereferencing vma, but vma
>> >will be set to NULL in i915_perf_destroy.
>>
>> I will not use stream->oa_buffer.vma->obj in vm_fault_oa based on your
>> earlier comments, so this should be taken care of.
>
>Aye.
>-Chris
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^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 18:47 ` Umesh Nerlige Ramappa
@ 2020-07-24 18:55 ` Chris Wilson
2020-07-24 19:35 ` Umesh Nerlige Ramappa
0 siblings, 1 reply; 33+ messages in thread
From: Chris Wilson @ 2020-07-24 18:55 UTC (permalink / raw)
To: Umesh Nerlige Ramappa; +Cc: intel-gfx
Quoting Umesh Nerlige Ramappa (2020-07-24 19:47:37)
> On Fri, Jul 24, 2020 at 05:34:11PM +0100, Chris Wilson wrote:
> >Quoting Umesh Nerlige Ramappa (2020-07-24 17:29:56)
> >> On Fri, Jul 24, 2020 at 01:42:33PM +0100, Chris Wilson wrote:
> >> >Quoting Umesh Nerlige Ramappa (2020-07-24 01:19:01)
> >> >> From: Piotr Maciejewski <piotr.maciejewski@intel.com>
> >> >>
> >> >> i915 used to support time based sampling mode which is good for overall
> >> >> system monitoring, but is not enough for query mode used to measure a
> >> >> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
> >> >> implementation for query, but Gen12+ requires a new approach for query
> >> >> based on triggered reports within oa buffer.
> >> >>
> >> >> Triggering reports into the OA buffer is achieved by writing into a
> >> >> a trigger register. Optionally an unused counter/register is set with a
> >> >> marker value such that a triggered report can be identified in the OA
> >> >> buffer. Reports are usually triggered at the start and end of work that
> >> >> is measured.
> >> >>
> >> >> Since OA buffer is large and queries can be frequent, an efficient way
> >> >> to look for triggered reports is required. By knowing the current head
> >> >> and tail offsets into the OA buffer, it is easier to determine the
> >> >> locality of the reports of interest.
> >> >>
> >> >> Current perf OA interface does not expose head/tail information to the
> >> >> user and it filters out invalid reports before sending data to user.
> >> >> Also considering limited size of user buffer used during a query,
> >> >> creating a 1:1 copy of the OA buffer at the user space added undesired
> >> >> complexity.
> >> >>
> >> >> The solution was to map the OA buffer to user space provided
> >> >>
> >> >> (1) that it is accessed from a privileged user.
> >> >> (2) OA report filtering is not used.
> >> >>
> >> >> These 2 conditions would satisfy the safety criteria that the current
> >> >> perf interface addresses.
> >> >>
> >> >> To enable the query:
> >> >> - Add an ioctl to expose head and tail to the user
> >> >> - Add an ioctl to return size and offset of the OA buffer
> >> >> - Map the OA buffer to the user space
> >> >>
> >> >> v2:
> >> >> - Improve commit message (Chris)
> >> >> - Do not mmap based on gem object filp. Instead, use perf_fd and support
> >> >> mmap syscall (Chris)
> >> >> - Pass non-zero offset in mmap to enforce the right object is
> >> >> mapped (Chris)
> >> >> - Do not expose gpu_address (Chris)
> >> >> - Verify start and length of vma for page alignment (Lionel)
> >> >> - Move SQNTL config out (Lionel)
> >> >>
> >> >> v3: (Chris)
> >> >> - Omit redundant checks
> >> >> - Return VM_FAULT_SIGBUS is old stream is closed
> >> >> - Maintain reference counts to stream in vm_open and vm_close
> >> >> - Use switch to identify object to be mapped
> >> >>
> >> >> v4: Call kref_put on closing perf fd (Chris)
> >> >> v5:
> >> >> - Strip access to OA buffer from unprivileged child of a privileged
> >> >> parent. Use VM_DONTCOPY
> >> >> - Enforce MAP_PRIVATE by checking for VM_MAYSHARE
> >> >>
> >> >> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
> >> >> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> >> >> ---
> >> >> @@ -3314,12 +3427,113 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> >> >> i915_perf_destroy_locked(stream);
> >> >> mutex_unlock(&perf->lock);
> >> >>
> >> >> + unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
> >> >
> >> >You can just used unmap_mapping_range(file->f_mapping, 0, -1, 1);
> >> >It scales with the number of vma present, so no worries, be conservative.
> >> >(Otherwise, you need s/0/OA_BUFFER_OFFSET/.)
> >> >
> >> >> +
> >> >> /* Release the reference the perf stream kept on the driver. */
> >> >> drm_dev_put(&perf->i915->drm);
> >> >>
> >> >> return 0;
> >> >> }
> >> >>
> >> >> +static void vm_open_oa(struct vm_area_struct *vma)
> >> >> +{
> >> >> + struct i915_perf_stream *stream = vma->vm_private_data;
> >> >> +
> >> >> + GEM_BUG_ON(!stream);
> >> >> + perf_stream_get(stream);
> >> >> +}
> >> >> +
> >> >> +static void vm_close_oa(struct vm_area_struct *vma)
> >> >> +{
> >> >> + struct i915_perf_stream *stream = vma->vm_private_data;
> >> >> +
> >> >> + GEM_BUG_ON(!stream);
> >> >> + perf_stream_put(stream);
> >> >> +}
> >> >> +
> >> >> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
> >> >> +{
> >> >> + struct vm_area_struct *vma = vmf->vma;
> >> >> + struct i915_perf_stream *stream = vma->vm_private_data;
> >> >> + struct i915_perf *perf = stream->perf;
> >> >> + struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
> >> >> + int err;
> >> >> + bool closed;
> >> >
> >> >So vm_area_struct has a reference to the stream, that looks good now.
> >> >But there's no reference held to the vma itself.
> >>
> >> How do I get a reference to the vma.
> >
> >That would be i915_vma_get(), but you don't need to if we control the
> >order correctly, as then neither the PTE nor the ongoing faulthandler
> >last longer than the i915_perf_stream
>
> I see that the do_mmap()->mmap_region() takes a reference to file
>
> vma->vm_file = get_file(file);
By vma, I meant stream-oa_buffer.vma
> In our case this is perf_fd. do_munmap does a corresponding fput.
>
> so unmap_mapping_range() is never called unless both unmap() and
> close(perf_fd) are called by user (or process terminates).
The unmap_mapping_range() is called by destroy, so that should be
independent of userspace munmap.
> Is that good to take care of this ordering?
>
> This also explains why I cannot get a VM_FAULT_SIGBUS with the IGTs.
To hit the stream->close you'll need to race mmap/munmap against perf
destroy. You may like to challenge yourself to hit it :)
> >> >> + mutex_lock(&perf->lock);
> >> >> + closed = READ_ONCE(stream->closed);
> >> >> + mutex_unlock(&perf->lock);
> >> >
> >> >We do WRITE_ONCE(stream->closed, true) then invalidate all the mappings,
> >> >so that part looks good. The invalidate is serialised with the
> >> >vm_fault_oa, so we can just use a plain READ_ONCE(stream->closed) here
> >> >and not worry about the perf->lock.
> >>
> >> will do
> >> >
> >> >However... I think it should close&invalidate before releasing
> >> >stream->oa_buffer.
> >>
> >> will do
> >> >
> >> >And the read here of stream->oa_buffer should be after checking
> >> >stream->closed.
> >>
> >> I don't understand. I am checking for closed before remap_io_sg.
> >
> >It's the
> >
> >struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
> >
> >that's before the stream->closed check. That's dereferencing vma, but vma
> >will be set to NULL in i915_perf_destroy.
>
> I will not use stream->oa_buffer.vma->obj in vm_fault_oa based on your
> earlier comments, so this should be taken care of.
Aye.
-Chris
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^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 16:34 ` Chris Wilson
@ 2020-07-24 18:47 ` Umesh Nerlige Ramappa
2020-07-24 18:55 ` Chris Wilson
0 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-24 18:47 UTC (permalink / raw)
To: Chris Wilson; +Cc: intel-gfx
On Fri, Jul 24, 2020 at 05:34:11PM +0100, Chris Wilson wrote:
>Quoting Umesh Nerlige Ramappa (2020-07-24 17:29:56)
>> On Fri, Jul 24, 2020 at 01:42:33PM +0100, Chris Wilson wrote:
>> >Quoting Umesh Nerlige Ramappa (2020-07-24 01:19:01)
>> >> From: Piotr Maciejewski <piotr.maciejewski@intel.com>
>> >>
>> >> i915 used to support time based sampling mode which is good for overall
>> >> system monitoring, but is not enough for query mode used to measure a
>> >> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
>> >> implementation for query, but Gen12+ requires a new approach for query
>> >> based on triggered reports within oa buffer.
>> >>
>> >> Triggering reports into the OA buffer is achieved by writing into a
>> >> a trigger register. Optionally an unused counter/register is set with a
>> >> marker value such that a triggered report can be identified in the OA
>> >> buffer. Reports are usually triggered at the start and end of work that
>> >> is measured.
>> >>
>> >> Since OA buffer is large and queries can be frequent, an efficient way
>> >> to look for triggered reports is required. By knowing the current head
>> >> and tail offsets into the OA buffer, it is easier to determine the
>> >> locality of the reports of interest.
>> >>
>> >> Current perf OA interface does not expose head/tail information to the
>> >> user and it filters out invalid reports before sending data to user.
>> >> Also considering limited size of user buffer used during a query,
>> >> creating a 1:1 copy of the OA buffer at the user space added undesired
>> >> complexity.
>> >>
>> >> The solution was to map the OA buffer to user space provided
>> >>
>> >> (1) that it is accessed from a privileged user.
>> >> (2) OA report filtering is not used.
>> >>
>> >> These 2 conditions would satisfy the safety criteria that the current
>> >> perf interface addresses.
>> >>
>> >> To enable the query:
>> >> - Add an ioctl to expose head and tail to the user
>> >> - Add an ioctl to return size and offset of the OA buffer
>> >> - Map the OA buffer to the user space
>> >>
>> >> v2:
>> >> - Improve commit message (Chris)
>> >> - Do not mmap based on gem object filp. Instead, use perf_fd and support
>> >> mmap syscall (Chris)
>> >> - Pass non-zero offset in mmap to enforce the right object is
>> >> mapped (Chris)
>> >> - Do not expose gpu_address (Chris)
>> >> - Verify start and length of vma for page alignment (Lionel)
>> >> - Move SQNTL config out (Lionel)
>> >>
>> >> v3: (Chris)
>> >> - Omit redundant checks
>> >> - Return VM_FAULT_SIGBUS is old stream is closed
>> >> - Maintain reference counts to stream in vm_open and vm_close
>> >> - Use switch to identify object to be mapped
>> >>
>> >> v4: Call kref_put on closing perf fd (Chris)
>> >> v5:
>> >> - Strip access to OA buffer from unprivileged child of a privileged
>> >> parent. Use VM_DONTCOPY
>> >> - Enforce MAP_PRIVATE by checking for VM_MAYSHARE
>> >>
>> >> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
>> >> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
>> >> ---
>> >> @@ -3314,12 +3427,113 @@ static int i915_perf_release(struct inode *inode, struct file *file)
>> >> i915_perf_destroy_locked(stream);
>> >> mutex_unlock(&perf->lock);
>> >>
>> >> + unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
>> >
>> >You can just used unmap_mapping_range(file->f_mapping, 0, -1, 1);
>> >It scales with the number of vma present, so no worries, be conservative.
>> >(Otherwise, you need s/0/OA_BUFFER_OFFSET/.)
>> >
>> >> +
>> >> /* Release the reference the perf stream kept on the driver. */
>> >> drm_dev_put(&perf->i915->drm);
>> >>
>> >> return 0;
>> >> }
>> >>
>> >> +static void vm_open_oa(struct vm_area_struct *vma)
>> >> +{
>> >> + struct i915_perf_stream *stream = vma->vm_private_data;
>> >> +
>> >> + GEM_BUG_ON(!stream);
>> >> + perf_stream_get(stream);
>> >> +}
>> >> +
>> >> +static void vm_close_oa(struct vm_area_struct *vma)
>> >> +{
>> >> + struct i915_perf_stream *stream = vma->vm_private_data;
>> >> +
>> >> + GEM_BUG_ON(!stream);
>> >> + perf_stream_put(stream);
>> >> +}
>> >> +
>> >> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
>> >> +{
>> >> + struct vm_area_struct *vma = vmf->vma;
>> >> + struct i915_perf_stream *stream = vma->vm_private_data;
>> >> + struct i915_perf *perf = stream->perf;
>> >> + struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
>> >> + int err;
>> >> + bool closed;
>> >
>> >So vm_area_struct has a reference to the stream, that looks good now.
>> >But there's no reference held to the vma itself.
>>
>> How do I get a reference to the vma.
>
>That would be i915_vma_get(), but you don't need to if we control the
>order correctly, as then neither the PTE nor the ongoing faulthandler
>last longer than the i915_perf_stream
I see that the do_mmap()->mmap_region() takes a reference to file
vma->vm_file = get_file(file);
In our case this is perf_fd. do_munmap does a corresponding fput.
so unmap_mapping_range() is never called unless both unmap() and
close(perf_fd) are called by user (or process terminates).
Is that good to take care of this ordering?
This also explains why I cannot get a VM_FAULT_SIGBUS with the IGTs.
>
>> >> + mutex_lock(&perf->lock);
>> >> + closed = READ_ONCE(stream->closed);
>> >> + mutex_unlock(&perf->lock);
>> >
>> >We do WRITE_ONCE(stream->closed, true) then invalidate all the mappings,
>> >so that part looks good. The invalidate is serialised with the
>> >vm_fault_oa, so we can just use a plain READ_ONCE(stream->closed) here
>> >and not worry about the perf->lock.
>>
>> will do
>> >
>> >However... I think it should close&invalidate before releasing
>> >stream->oa_buffer.
>>
>> will do
>> >
>> >And the read here of stream->oa_buffer should be after checking
>> >stream->closed.
>>
>> I don't understand. I am checking for closed before remap_io_sg.
>
>It's the
>
>struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
>
>that's before the stream->closed check. That's dereferencing vma, but vma
>will be set to NULL in i915_perf_destroy.
I will not use stream->oa_buffer.vma->obj in vm_fault_oa based on your
earlier comments, so this should be taken care of.
Thanks,
Umesh
>-Chris
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^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 16:29 ` Umesh Nerlige Ramappa
@ 2020-07-24 16:34 ` Chris Wilson
2020-07-24 18:47 ` Umesh Nerlige Ramappa
0 siblings, 1 reply; 33+ messages in thread
From: Chris Wilson @ 2020-07-24 16:34 UTC (permalink / raw)
To: Umesh Nerlige Ramappa; +Cc: intel-gfx
Quoting Umesh Nerlige Ramappa (2020-07-24 17:29:56)
> On Fri, Jul 24, 2020 at 01:42:33PM +0100, Chris Wilson wrote:
> >Quoting Umesh Nerlige Ramappa (2020-07-24 01:19:01)
> >> From: Piotr Maciejewski <piotr.maciejewski@intel.com>
> >>
> >> i915 used to support time based sampling mode which is good for overall
> >> system monitoring, but is not enough for query mode used to measure a
> >> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
> >> implementation for query, but Gen12+ requires a new approach for query
> >> based on triggered reports within oa buffer.
> >>
> >> Triggering reports into the OA buffer is achieved by writing into a
> >> a trigger register. Optionally an unused counter/register is set with a
> >> marker value such that a triggered report can be identified in the OA
> >> buffer. Reports are usually triggered at the start and end of work that
> >> is measured.
> >>
> >> Since OA buffer is large and queries can be frequent, an efficient way
> >> to look for triggered reports is required. By knowing the current head
> >> and tail offsets into the OA buffer, it is easier to determine the
> >> locality of the reports of interest.
> >>
> >> Current perf OA interface does not expose head/tail information to the
> >> user and it filters out invalid reports before sending data to user.
> >> Also considering limited size of user buffer used during a query,
> >> creating a 1:1 copy of the OA buffer at the user space added undesired
> >> complexity.
> >>
> >> The solution was to map the OA buffer to user space provided
> >>
> >> (1) that it is accessed from a privileged user.
> >> (2) OA report filtering is not used.
> >>
> >> These 2 conditions would satisfy the safety criteria that the current
> >> perf interface addresses.
> >>
> >> To enable the query:
> >> - Add an ioctl to expose head and tail to the user
> >> - Add an ioctl to return size and offset of the OA buffer
> >> - Map the OA buffer to the user space
> >>
> >> v2:
> >> - Improve commit message (Chris)
> >> - Do not mmap based on gem object filp. Instead, use perf_fd and support
> >> mmap syscall (Chris)
> >> - Pass non-zero offset in mmap to enforce the right object is
> >> mapped (Chris)
> >> - Do not expose gpu_address (Chris)
> >> - Verify start and length of vma for page alignment (Lionel)
> >> - Move SQNTL config out (Lionel)
> >>
> >> v3: (Chris)
> >> - Omit redundant checks
> >> - Return VM_FAULT_SIGBUS is old stream is closed
> >> - Maintain reference counts to stream in vm_open and vm_close
> >> - Use switch to identify object to be mapped
> >>
> >> v4: Call kref_put on closing perf fd (Chris)
> >> v5:
> >> - Strip access to OA buffer from unprivileged child of a privileged
> >> parent. Use VM_DONTCOPY
> >> - Enforce MAP_PRIVATE by checking for VM_MAYSHARE
> >>
> >> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
> >> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> >> ---
> >> @@ -3314,12 +3427,113 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> >> i915_perf_destroy_locked(stream);
> >> mutex_unlock(&perf->lock);
> >>
> >> + unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
> >
> >You can just used unmap_mapping_range(file->f_mapping, 0, -1, 1);
> >It scales with the number of vma present, so no worries, be conservative.
> >(Otherwise, you need s/0/OA_BUFFER_OFFSET/.)
> >
> >> +
> >> /* Release the reference the perf stream kept on the driver. */
> >> drm_dev_put(&perf->i915->drm);
> >>
> >> return 0;
> >> }
> >>
> >> +static void vm_open_oa(struct vm_area_struct *vma)
> >> +{
> >> + struct i915_perf_stream *stream = vma->vm_private_data;
> >> +
> >> + GEM_BUG_ON(!stream);
> >> + perf_stream_get(stream);
> >> +}
> >> +
> >> +static void vm_close_oa(struct vm_area_struct *vma)
> >> +{
> >> + struct i915_perf_stream *stream = vma->vm_private_data;
> >> +
> >> + GEM_BUG_ON(!stream);
> >> + perf_stream_put(stream);
> >> +}
> >> +
> >> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
> >> +{
> >> + struct vm_area_struct *vma = vmf->vma;
> >> + struct i915_perf_stream *stream = vma->vm_private_data;
> >> + struct i915_perf *perf = stream->perf;
> >> + struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
> >> + int err;
> >> + bool closed;
> >
> >So vm_area_struct has a reference to the stream, that looks good now.
> >But there's no reference held to the vma itself.
>
> How do I get a reference to the vma.
That would be i915_vma_get(), but you don't need to if we control the
order correctly, as then neither the PTE nor the ongoing faulthandler
last longer than the i915_perf_stream
> >> + mutex_lock(&perf->lock);
> >> + closed = READ_ONCE(stream->closed);
> >> + mutex_unlock(&perf->lock);
> >
> >We do WRITE_ONCE(stream->closed, true) then invalidate all the mappings,
> >so that part looks good. The invalidate is serialised with the
> >vm_fault_oa, so we can just use a plain READ_ONCE(stream->closed) here
> >and not worry about the perf->lock.
>
> will do
> >
> >However... I think it should close&invalidate before releasing
> >stream->oa_buffer.
>
> will do
> >
> >And the read here of stream->oa_buffer should be after checking
> >stream->closed.
>
> I don't understand. I am checking for closed before remap_io_sg.
It's the
struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
that's before the stream->closed check. That's dereferencing vma, but vma
will be set to NULL in i915_perf_destroy.
-Chris
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^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 12:42 ` Chris Wilson
@ 2020-07-24 16:29 ` Umesh Nerlige Ramappa
2020-07-24 16:34 ` Chris Wilson
0 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-24 16:29 UTC (permalink / raw)
To: Chris Wilson; +Cc: intel-gfx
On Fri, Jul 24, 2020 at 01:42:33PM +0100, Chris Wilson wrote:
>Quoting Umesh Nerlige Ramappa (2020-07-24 01:19:01)
>> From: Piotr Maciejewski <piotr.maciejewski@intel.com>
>>
>> i915 used to support time based sampling mode which is good for overall
>> system monitoring, but is not enough for query mode used to measure a
>> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
>> implementation for query, but Gen12+ requires a new approach for query
>> based on triggered reports within oa buffer.
>>
>> Triggering reports into the OA buffer is achieved by writing into a
>> a trigger register. Optionally an unused counter/register is set with a
>> marker value such that a triggered report can be identified in the OA
>> buffer. Reports are usually triggered at the start and end of work that
>> is measured.
>>
>> Since OA buffer is large and queries can be frequent, an efficient way
>> to look for triggered reports is required. By knowing the current head
>> and tail offsets into the OA buffer, it is easier to determine the
>> locality of the reports of interest.
>>
>> Current perf OA interface does not expose head/tail information to the
>> user and it filters out invalid reports before sending data to user.
>> Also considering limited size of user buffer used during a query,
>> creating a 1:1 copy of the OA buffer at the user space added undesired
>> complexity.
>>
>> The solution was to map the OA buffer to user space provided
>>
>> (1) that it is accessed from a privileged user.
>> (2) OA report filtering is not used.
>>
>> These 2 conditions would satisfy the safety criteria that the current
>> perf interface addresses.
>>
>> To enable the query:
>> - Add an ioctl to expose head and tail to the user
>> - Add an ioctl to return size and offset of the OA buffer
>> - Map the OA buffer to the user space
>>
>> v2:
>> - Improve commit message (Chris)
>> - Do not mmap based on gem object filp. Instead, use perf_fd and support
>> mmap syscall (Chris)
>> - Pass non-zero offset in mmap to enforce the right object is
>> mapped (Chris)
>> - Do not expose gpu_address (Chris)
>> - Verify start and length of vma for page alignment (Lionel)
>> - Move SQNTL config out (Lionel)
>>
>> v3: (Chris)
>> - Omit redundant checks
>> - Return VM_FAULT_SIGBUS is old stream is closed
>> - Maintain reference counts to stream in vm_open and vm_close
>> - Use switch to identify object to be mapped
>>
>> v4: Call kref_put on closing perf fd (Chris)
>> v5:
>> - Strip access to OA buffer from unprivileged child of a privileged
>> parent. Use VM_DONTCOPY
>> - Enforce MAP_PRIVATE by checking for VM_MAYSHARE
>>
>> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
>> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
>> ---
>> @@ -3314,12 +3427,113 @@ static int i915_perf_release(struct inode *inode, struct file *file)
>> i915_perf_destroy_locked(stream);
>> mutex_unlock(&perf->lock);
>>
>> + unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
>
>You can just used unmap_mapping_range(file->f_mapping, 0, -1, 1);
>It scales with the number of vma present, so no worries, be conservative.
>(Otherwise, you need s/0/OA_BUFFER_OFFSET/.)
>
>> +
>> /* Release the reference the perf stream kept on the driver. */
>> drm_dev_put(&perf->i915->drm);
>>
>> return 0;
>> }
>>
>> +static void vm_open_oa(struct vm_area_struct *vma)
>> +{
>> + struct i915_perf_stream *stream = vma->vm_private_data;
>> +
>> + GEM_BUG_ON(!stream);
>> + perf_stream_get(stream);
>> +}
>> +
>> +static void vm_close_oa(struct vm_area_struct *vma)
>> +{
>> + struct i915_perf_stream *stream = vma->vm_private_data;
>> +
>> + GEM_BUG_ON(!stream);
>> + perf_stream_put(stream);
>> +}
>> +
>> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
>> +{
>> + struct vm_area_struct *vma = vmf->vma;
>> + struct i915_perf_stream *stream = vma->vm_private_data;
>> + struct i915_perf *perf = stream->perf;
>> + struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
>> + int err;
>> + bool closed;
>
>So vm_area_struct has a reference to the stream, that looks good now.
>But there's no reference held to the vma itself.
How do I get a reference to the vma.
>
>> + mutex_lock(&perf->lock);
>> + closed = READ_ONCE(stream->closed);
>> + mutex_unlock(&perf->lock);
>
>We do WRITE_ONCE(stream->closed, true) then invalidate all the mappings,
>so that part looks good. The invalidate is serialised with the
>vm_fault_oa, so we can just use a plain READ_ONCE(stream->closed) here
>and not worry about the perf->lock.
will do
>
>However... I think it should close&invalidate before releasing
>stream->oa_buffer.
will do
>
>And the read here of stream->oa_buffer should be after checking
>stream->closed.
I don't understand. I am checking for closed before remap_io_sg.
Thanks,
Umesh
>
>> +
>> + if (closed)
>> + return VM_FAULT_SIGBUS;
>> +
>> + err = i915_gem_object_pin_pages(obj);
>> + if (err)
>> + goto out;
>> +
>> + err = remap_io_sg(vma,
>> + vma->vm_start, vma->vm_end - vma->vm_start,
>> + obj->mm.pages->sgl, -1);
>> +
>> + i915_gem_object_unpin_pages(obj);
>
>I'd be really tempted here not to use stream->oa_buffer.vma->obj at all.
>We know the oa_buffer is pinned while it is open (and we know we will be
>serialised against close/destroy), so this can be reduced to just
>
> err = remap_io_sg(vma,
> vma->vm_start, vma->vm_end - vma->vm_start,
> stream->oa_buffer.vma->pages, -1);
>
>> +
>> +out:
>> + return i915_error_to_vmf_fault(err);
>> +}
>> +
>> +static const struct vm_operations_struct vm_ops_oa = {
>> + .open = vm_open_oa,
>> + .close = vm_close_oa,
>> + .fault = vm_fault_oa,
>> +};
>> +
>> +int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
>> +{
>> + struct i915_perf_stream *stream = file->private_data;
>> +
>> + /* mmap-ing OA buffer to user space MUST absolutely be privileged */
>> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
>> + DRM_DEBUG("Insufficient privileges to map OA buffer\n");
>> + return -EACCES;
>> + }
>> +
>> + switch (vma->vm_pgoff) {
>> + /* A non-zero offset ensures that we are mapping the right object. Also
>> + * leaves room for future objects added to this implementation.
>> + */
>
>/*
> * Kernel block comment style.
> */
>
>(There's a few subsystems, i.e net/ that use the other style, but we've
>switch over to the more common open style and try to stick to it.)
>
>> + case I915_PERF_OA_BUFFER_MMAP_OFFSET:
>> + if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
>> + return -EINVAL;
>> +
>> + /* Only support VM_READ. Enforce MAP_PRIVATE by checking for
>> + * VM_MAYSHARE.
>> + */
>> + if (vma->vm_flags & (VM_WRITE | VM_EXEC |
>> + VM_SHARED | VM_MAYSHARE))
>> + return -EINVAL;
>> +
>> + vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
>> +
>> + /* If the privileged parent forks and child drops root
>> + * privilege, we do not want the child to retain access to the
>> + * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
>> + * cases.
>> + */
>
>The explanations are extremely valuable :)
>
>> + vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
>> + VM_DONTDUMP | VM_DONTCOPY;
>> + break;
>> +
>> + default:
>> + return -EINVAL;
>> + }
>> +
>> + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
>> + vma->vm_private_data = stream;
>> + vma->vm_ops = &vm_ops_oa;
>> + vm_open_oa(vma);
>> +
>> + return 0;
>> +}
_______________________________________________
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Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 0:19 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
@ 2020-07-24 12:42 ` Chris Wilson
2020-07-24 16:29 ` Umesh Nerlige Ramappa
0 siblings, 1 reply; 33+ messages in thread
From: Chris Wilson @ 2020-07-24 12:42 UTC (permalink / raw)
To: Umesh Nerlige Ramappa, intel-gfx
Quoting Umesh Nerlige Ramappa (2020-07-24 01:19:01)
> From: Piotr Maciejewski <piotr.maciejewski@intel.com>
>
> i915 used to support time based sampling mode which is good for overall
> system monitoring, but is not enough for query mode used to measure a
> single draw call or dispatch. Gen9-Gen11 are using current i915 perf
> implementation for query, but Gen12+ requires a new approach for query
> based on triggered reports within oa buffer.
>
> Triggering reports into the OA buffer is achieved by writing into a
> a trigger register. Optionally an unused counter/register is set with a
> marker value such that a triggered report can be identified in the OA
> buffer. Reports are usually triggered at the start and end of work that
> is measured.
>
> Since OA buffer is large and queries can be frequent, an efficient way
> to look for triggered reports is required. By knowing the current head
> and tail offsets into the OA buffer, it is easier to determine the
> locality of the reports of interest.
>
> Current perf OA interface does not expose head/tail information to the
> user and it filters out invalid reports before sending data to user.
> Also considering limited size of user buffer used during a query,
> creating a 1:1 copy of the OA buffer at the user space added undesired
> complexity.
>
> The solution was to map the OA buffer to user space provided
>
> (1) that it is accessed from a privileged user.
> (2) OA report filtering is not used.
>
> These 2 conditions would satisfy the safety criteria that the current
> perf interface addresses.
>
> To enable the query:
> - Add an ioctl to expose head and tail to the user
> - Add an ioctl to return size and offset of the OA buffer
> - Map the OA buffer to the user space
>
> v2:
> - Improve commit message (Chris)
> - Do not mmap based on gem object filp. Instead, use perf_fd and support
> mmap syscall (Chris)
> - Pass non-zero offset in mmap to enforce the right object is
> mapped (Chris)
> - Do not expose gpu_address (Chris)
> - Verify start and length of vma for page alignment (Lionel)
> - Move SQNTL config out (Lionel)
>
> v3: (Chris)
> - Omit redundant checks
> - Return VM_FAULT_SIGBUS is old stream is closed
> - Maintain reference counts to stream in vm_open and vm_close
> - Use switch to identify object to be mapped
>
> v4: Call kref_put on closing perf fd (Chris)
> v5:
> - Strip access to OA buffer from unprivileged child of a privileged
> parent. Use VM_DONTCOPY
> - Enforce MAP_PRIVATE by checking for VM_MAYSHARE
>
> Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> ---
> @@ -3314,12 +3427,113 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> i915_perf_destroy_locked(stream);
> mutex_unlock(&perf->lock);
>
> + unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
You can just used unmap_mapping_range(file->f_mapping, 0, -1, 1);
It scales with the number of vma present, so no worries, be conservative.
(Otherwise, you need s/0/OA_BUFFER_OFFSET/.)
> +
> /* Release the reference the perf stream kept on the driver. */
> drm_dev_put(&perf->i915->drm);
>
> return 0;
> }
>
> +static void vm_open_oa(struct vm_area_struct *vma)
> +{
> + struct i915_perf_stream *stream = vma->vm_private_data;
> +
> + GEM_BUG_ON(!stream);
> + perf_stream_get(stream);
> +}
> +
> +static void vm_close_oa(struct vm_area_struct *vma)
> +{
> + struct i915_perf_stream *stream = vma->vm_private_data;
> +
> + GEM_BUG_ON(!stream);
> + perf_stream_put(stream);
> +}
> +
> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
> +{
> + struct vm_area_struct *vma = vmf->vma;
> + struct i915_perf_stream *stream = vma->vm_private_data;
> + struct i915_perf *perf = stream->perf;
> + struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
> + int err;
> + bool closed;
So vm_area_struct has a reference to the stream, that looks good now.
But there's no reference held to the vma itself.
> + mutex_lock(&perf->lock);
> + closed = READ_ONCE(stream->closed);
> + mutex_unlock(&perf->lock);
We do WRITE_ONCE(stream->closed, true) then invalidate all the mappings,
so that part looks good. The invalidate is serialised with the
vm_fault_oa, so we can just use a plain READ_ONCE(stream->closed) here
and not worry about the perf->lock.
However... I think it should close&invalidate before releasing
stream->oa_buffer.
And the read here of stream->oa_buffer should be after checking
stream->closed.
> +
> + if (closed)
> + return VM_FAULT_SIGBUS;
> +
> + err = i915_gem_object_pin_pages(obj);
> + if (err)
> + goto out;
> +
> + err = remap_io_sg(vma,
> + vma->vm_start, vma->vm_end - vma->vm_start,
> + obj->mm.pages->sgl, -1);
> +
> + i915_gem_object_unpin_pages(obj);
I'd be really tempted here not to use stream->oa_buffer.vma->obj at all.
We know the oa_buffer is pinned while it is open (and we know we will be
serialised against close/destroy), so this can be reduced to just
err = remap_io_sg(vma,
vma->vm_start, vma->vm_end - vma->vm_start,
stream->oa_buffer.vma->pages, -1);
> +
> +out:
> + return i915_error_to_vmf_fault(err);
> +}
> +
> +static const struct vm_operations_struct vm_ops_oa = {
> + .open = vm_open_oa,
> + .close = vm_close_oa,
> + .fault = vm_fault_oa,
> +};
> +
> +int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
> +{
> + struct i915_perf_stream *stream = file->private_data;
> +
> + /* mmap-ing OA buffer to user space MUST absolutely be privileged */
> + if (i915_perf_stream_paranoid && !perfmon_capable()) {
> + DRM_DEBUG("Insufficient privileges to map OA buffer\n");
> + return -EACCES;
> + }
> +
> + switch (vma->vm_pgoff) {
> + /* A non-zero offset ensures that we are mapping the right object. Also
> + * leaves room for future objects added to this implementation.
> + */
/*
* Kernel block comment style.
*/
(There's a few subsystems, i.e net/ that use the other style, but we've
switch over to the more common open style and try to stick to it.)
> + case I915_PERF_OA_BUFFER_MMAP_OFFSET:
> + if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
> + return -EINVAL;
> +
> + /* Only support VM_READ. Enforce MAP_PRIVATE by checking for
> + * VM_MAYSHARE.
> + */
> + if (vma->vm_flags & (VM_WRITE | VM_EXEC |
> + VM_SHARED | VM_MAYSHARE))
> + return -EINVAL;
> +
> + vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
> +
> + /* If the privileged parent forks and child drops root
> + * privilege, we do not want the child to retain access to the
> + * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
> + * cases.
> + */
The explanations are extremely valuable :)
> + vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
> + VM_DONTDUMP | VM_DONTCOPY;
> + break;
> +
> + default:
> + return -EINVAL;
> + }
> +
> + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
> + vma->vm_private_data = stream;
> + vma->vm_ops = &vm_ops_oa;
> + vm_open_oa(vma);
> +
> + return 0;
> +}
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Registered Office: Pipers Way, Swindon SN3 1RJ
VAT No: 860 2173 47
This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.
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^ permalink raw reply [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-24 0:18 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-07-24 0:19 ` Umesh Nerlige Ramappa
2020-07-24 12:42 ` Chris Wilson
0 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-24 0:19 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
From: Piotr Maciejewski <piotr.maciejewski@intel.com>
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is
mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
v4: Call kref_put on closing perf fd (Chris)
v5:
- Strip access to OA buffer from unprivileged child of a privileged
parent. Use VM_DONTCOPY
- Enforce MAP_PRIVATE by checking for VM_MAYSHARE
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 226 ++++++++++++++++++++++-
drivers/gpu/drm/i915/i915_perf_types.h | 17 ++
include/uapi/drm/i915_drm.h | 32 ++++
5 files changed, 276 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 2f23aad12c60..4a374b96eca6 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -378,6 +380,24 @@ static struct ctl_table_header *sysctl_header;
static enum hrtimer_restart oa_poll_check_timer_cb(struct hrtimer *hrtimer);
+static void free_stream(struct kref *kref)
+{
+ struct i915_perf_stream *stream =
+ container_of(kref, typeof(*stream), refcount);
+
+ kfree(stream);
+}
+
+static void perf_stream_get(struct i915_perf_stream *stream)
+{
+ kref_get(&stream->refcount);
+}
+
+static void perf_stream_put(struct i915_perf_stream *stream)
+{
+ kref_put(&stream->refcount, free_stream);
+}
+
void i915_oa_config_release(struct kref *ref)
{
struct i915_oa_config *oa_config =
@@ -434,6 +454,30 @@ static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream)
return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;
}
+static u32 gen12_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+
+ return intel_uncore_read(uncore, GEN12_OAG_OAHEADPTR) &
+ GEN12_OAG_OAHEADPTR_MASK;
+}
+
+static u32 gen8_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+
+ return intel_uncore_read(uncore, GEN8_OAHEADPTR) &
+ GEN8_OAHEADPTR_MASK;
+}
+
+static u32 gen7_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+ u32 oastatus2 = intel_uncore_read(uncore, GEN7_OASTATUS2);
+
+ return oastatus2 & GEN7_OASTATUS2_HEAD_MASK;
+}
+
/**
* oa_buffer_check_unlocked - check for data and update tail ptr state
* @stream: i915 stream instance
@@ -2934,6 +2978,7 @@ static int i915_oa_stream_init(struct i915_perf_stream *stream,
stream->poll_check_timer.function = oa_poll_check_timer_cb;
init_waitqueue_head(&stream->poll_wq);
spin_lock_init(&stream->oa_buffer.ptr_lock);
+ kref_init(&stream->refcount);
return 0;
@@ -3214,6 +3259,69 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+/**
+ * i915_perf_oa_buffer_head_tail_locked - head and tail of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer head and tail filled by this function.
+ */
+static int i915_perf_oa_buffer_head_tail_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_head_tail ht;
+ void __user *output = (void __user *)arg;
+ u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (!output)
+ return -EINVAL;
+
+ memset(&ht, 0, sizeof(ht));
+
+ ht.head = stream->perf->ops.oa_hw_head_read(stream) - gtt_offset;
+ ht.tail = stream->perf->ops.oa_hw_tail_read(stream) - gtt_offset;
+
+ if (copy_to_user(output, &ht, sizeof(ht)))
+ return -EFAULT;
+
+ return 0;
+}
+
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (!output)
+ return -EINVAL;
+
+ memset(&info, 0, sizeof(info));
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3239,6 +3347,10 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL:
+ return i915_perf_oa_buffer_head_tail_locked(stream, arg);
}
return -EINVAL;
@@ -3291,7 +3403,8 @@ static void i915_perf_destroy_locked(struct i915_perf_stream *stream)
if (stream->ctx)
i915_gem_context_put(stream->ctx);
- kfree(stream);
+ WRITE_ONCE(stream->closed, true);
+ perf_stream_put(stream);
}
/**
@@ -3314,12 +3427,113 @@ static int i915_perf_release(struct inode *inode, struct file *file)
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
+ unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
+
/* Release the reference the perf stream kept on the driver. */
drm_dev_put(&perf->i915->drm);
return 0;
}
+static void vm_open_oa(struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = vma->vm_private_data;
+
+ GEM_BUG_ON(!stream);
+ perf_stream_get(stream);
+}
+
+static void vm_close_oa(struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = vma->vm_private_data;
+
+ GEM_BUG_ON(!stream);
+ perf_stream_put(stream);
+}
+
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ struct i915_perf *perf = stream->perf;
+ struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
+ int err;
+ bool closed;
+
+ mutex_lock(&perf->lock);
+ closed = READ_ONCE(stream->closed);
+ mutex_unlock(&perf->lock);
+
+ if (closed)
+ return VM_FAULT_SIGBUS;
+
+ err = i915_gem_object_pin_pages(obj);
+ if (err)
+ goto out;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ obj->mm.pages->sgl, -1);
+
+ i915_gem_object_unpin_pages(obj);
+
+out:
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .open = vm_open_oa,
+ .close = vm_close_oa,
+ .fault = vm_fault_oa,
+};
+
+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ /* mmap-ing OA buffer to user space MUST absolutely be privileged */
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ /* A non-zero offset ensures that we are mapping the right object. Also
+ * leaves room for future objects added to this implementation.
+ */
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ /* Only support VM_READ. Enforce MAP_PRIVATE by checking for
+ * VM_MAYSHARE.
+ */
+ if (vma->vm_flags & (VM_WRITE | VM_EXEC |
+ VM_SHARED | VM_MAYSHARE))
+ return -EINVAL;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
+
+ /* If the privileged parent forks and child drops root
+ * privilege, we do not want the child to retain access to the
+ * mapped OA buffer. Explicitly set VM_DONTCOPY to avoid such
+ * cases.
+ */
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND |
+ VM_DONTDUMP | VM_DONTCOPY;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+ vm_open_oa(vma);
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3332,6 +3546,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4260,6 +4475,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.oa_disable = gen7_oa_disable;
perf->ops.read = gen7_oa_read;
perf->ops.oa_hw_tail_read = gen7_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen7_oa_hw_head_read;
perf->oa_formats = hsw_oa_formats;
} else if (HAS_LOGICAL_RING_CONTEXTS(i915)) {
@@ -4291,6 +4507,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen8_enable_metric_set;
perf->ops.disable_metric_set = gen8_disable_metric_set;
perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
if (IS_GEN(i915, 8)) {
perf->ctx_oactxctrl_offset = 0x120;
@@ -4318,6 +4535,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen8_enable_metric_set;
perf->ops.disable_metric_set = gen10_disable_metric_set;
perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
if (IS_GEN(i915, 10)) {
perf->ctx_oactxctrl_offset = 0x128;
@@ -4342,6 +4560,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen12_enable_metric_set;
perf->ops.disable_metric_set = gen12_disable_metric_set;
perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen12_oa_hw_head_read;
perf->ctx_flexeu0_offset = 0;
perf->ctx_oactxctrl_offset = 0x144;
@@ -4456,8 +4675,11 @@ int i915_perf_ioctl_version(void)
*
* - OA buffer head/tail/status/buffer registers for read only
* - OA counters A18, A19, A20 for read/write
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
index a36a455ae336..2efbe35c5fa9 100644
--- a/drivers/gpu/drm/i915/i915_perf_types.h
+++ b/drivers/gpu/drm/i915/i915_perf_types.h
@@ -311,6 +311,18 @@ struct i915_perf_stream {
* buffer should be checked for available data.
*/
u64 poll_oa_period;
+
+ /**
+ * @closed: Open or closed state of the stream.
+ * True if stream is closed.
+ */
+ bool closed;
+
+ /**
+ * @refcount: References to the mapped OA buffer managed by this
+ * stream.
+ */
+ struct kref refcount;
};
/**
@@ -377,6 +389,11 @@ struct i915_oa_ops {
* generations.
*/
u32 (*oa_hw_tail_read)(struct i915_perf_stream *stream);
+
+ /**
+ * @oa_hw_head_read: read the OA head pointer register
+ */
+ u32 (*oa_hw_head_read)(struct i915_perf_stream *stream);
};
struct i915_perf {
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..2042f6339182 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,38 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IO('i', 0x3)
+
+/**
+ * OA buffer size and offset.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 size;
+ __u32 offset;
+ __u64 reserved[4];
+};
+
+/**
+ * Returns current position of OA buffer head and tail.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL _IO('i', 0x4)
+
+/**
+ * OA buffer head and tail.
+ */
+struct drm_i915_perf_oa_buffer_head_tail {
+ __u32 head;
+ __u32 tail;
+ __u64 reserved[4];
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
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^ permalink raw reply related [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-21 2:17 ` Umesh Nerlige Ramappa
@ 2020-07-21 8:52 ` Chris Wilson
0 siblings, 0 replies; 33+ messages in thread
From: Chris Wilson @ 2020-07-21 8:52 UTC (permalink / raw)
To: Umesh Nerlige Ramappa, intel-gfx
Quoting Umesh Nerlige Ramappa (2020-07-21 03:17:59)
> Hi Chris,
>
> I have added your comments, but I have a few questions below:
>
> Thanks for your help,
> Umesh
>
> On Mon, Jul 20, 2020 at 07:00:12PM -0700, Umesh Nerlige Ramappa wrote:
> >From: Piotr Maciejewski <piotr.maciejewski@intel.com>
> >+static void vm_open_oa(struct vm_area_struct *vma)
> >+{
> >+ struct i915_perf_stream *stream = vma->vm_private_data;
> >+
> >+ GEM_BUG_ON(!stream);
> >+ kref_get(&stream->refcount);
>
> When user calls mmap, after this call the count is 2 (since kref_init
> started off the count with 1).
>
> >+}
> >+
> >+static void vm_close_oa(struct vm_area_struct *vma)
> >+{
> >+ struct i915_perf_stream *stream = vma->vm_private_data;
> >+
> >+ GEM_BUG_ON(!stream);
> >+ kref_put(&stream->refcount, free_stream);
>
> When the user closes perf fd or calls unmap, vm_close_oa is called and
> refcount goes to 1, so not sure how the refcount goes to 0 so that
> free_stream is called. Should I kref_put when closing perf fd also?
Yes, at a glance, I would say i915_perf_destroy_locked() should replace
the kfree(stream) with a kref_put.
> >+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
> >+{
> >+ struct vm_area_struct *vma = vmf->vma;
> >+ struct i915_perf_stream *stream = vma->vm_private_data;
> >+ struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
> >+ int err;
> >+
> >+ if (READ_ONCE(stream->closed))
> >+ return VM_FAULT_SIGBUS;
> >+
> >+ err = i915_gem_object_pin_pages(obj);
> >+ if (err)
> >+ goto out;
> >+
> >+ err = remap_io_sg(vma,
> >+ vma->vm_start, vma->vm_end - vma->vm_start,
> >+ obj->mm.pages->sgl, -1);
> >+
> >+ i915_gem_object_unpin_pages(obj);
> >+
> >+out:
> >+ return i915_error_to_vmf_fault(err);
> >+}
> >+
> >+static const struct vm_operations_struct vm_ops_oa = {
> >+ .open = vm_open_oa,
> >+ .close = vm_close_oa,
> >+ .fault = vm_fault_oa,
> >+};
> >+
> >+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
> >+{
> >+ struct i915_perf_stream *stream = file->private_data;
> >+
> >+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
> >+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
> >+ return -EACCES;
> >+ }
> >+
> >+ switch (vma->vm_pgoff) {
> >+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
> >+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
> >+ return -EINVAL;
> >+
> >+ if (vma->vm_flags & VM_WRITE)
> >+ return -EINVAL;
> >+
> >+ break;
> >+
> >+ default:
> >+ return -EINVAL;
> >+ }
> >+
> >+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC | VM_MAYSHARE);
> >+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
> >+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
> >+ vma->vm_private_data = stream;
> >+ vma->vm_ops = &vm_ops_oa;
> >+ vm_open_oa(vma);
>
> I am calling the open explicitly here to get the reference, otherwise I
> don't see open being called by anyone/anything.
The initial vm_ops->open is implicit, i.e. the mmap starts opened, and
the vm_ops->open() is only called when the vma is cloned (e.g. on
fork()).
> If user calls mmap multiple times, does he get a unique vma each time?
Yes.
> Do I need to track all of them (and their sizes) and then unmap them
> when perf_fd is closed?
Yes... But we can zap them all with a single unmap_mapping_range() call,
since they all exist within the perf_fd->f_mapping.
> >diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
> >index a36a455ae336..2efbe35c5fa9 100644
> >--- a/drivers/gpu/drm/i915/i915_perf_types.h
> >+++ b/drivers/gpu/drm/i915/i915_perf_types.h
> >@@ -311,6 +311,18 @@ struct i915_perf_stream {
> > * buffer should be checked for available data.
> > */
> > u64 poll_oa_period;
> >+
> >+ /**
> >+ * @closed: Open or closed state of the stream.
> >+ * True if stream is closed.
> >+ */
> >+ bool closed;
>
> closed is part of the stream itself, so I cannot kfree(stream) until the
> refcount goes to 0.
Correct. kfree must be part of the kref_put cb.
> >+ /**
> >+ * @refcount: References to the mapped OA buffer managed by this
> >+ * stream.
> >+ */
> >+ struct kref refcount;
> > };
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^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-21 2:00 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
@ 2020-07-21 2:17 ` Umesh Nerlige Ramappa
2020-07-21 8:52 ` Chris Wilson
0 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-21 2:17 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
Hi Chris,
I have added your comments, but I have a few questions below:
Thanks for your help,
Umesh
On Mon, Jul 20, 2020 at 07:00:12PM -0700, Umesh Nerlige Ramappa wrote:
>From: Piotr Maciejewski <piotr.maciejewski@intel.com>
>
>i915 used to support time based sampling mode which is good for overall
>system monitoring, but is not enough for query mode used to measure a
>single draw call or dispatch. Gen9-Gen11 are using current i915 perf
>implementation for query, but Gen12+ requires a new approach for query
>based on triggered reports within oa buffer.
>
>Triggering reports into the OA buffer is achieved by writing into a
>a trigger register. Optionally an unused counter/register is set with a
>marker value such that a triggered report can be identified in the OA
>buffer. Reports are usually triggered at the start and end of work that
>is measured.
>
>Since OA buffer is large and queries can be frequent, an efficient way
>to look for triggered reports is required. By knowing the current head
>and tail offsets into the OA buffer, it is easier to determine the
>locality of the reports of interest.
>
>Current perf OA interface does not expose head/tail information to the
>user and it filters out invalid reports before sending data to user.
>Also considering limited size of user buffer used during a query,
>creating a 1:1 copy of the OA buffer at the user space added undesired
>complexity.
>
>The solution was to map the OA buffer to user space provided
>
>(1) that it is accessed from a privileged user.
>(2) OA report filtering is not used.
>
>These 2 conditions would satisfy the safety criteria that the current
>perf interface addresses.
>
>To enable the query:
>- Add an ioctl to expose head and tail to the user
>- Add an ioctl to return size and offset of the OA buffer
>- Map the OA buffer to the user space
>
>v2:
>- Improve commit message (Chris)
>- Do not mmap based on gem object filp. Instead, use perf_fd and support
> mmap syscall (Chris)
>- Pass non-zero offset in mmap to enforce the right object is mapped (Chris)
>- Do not expose gpu_address (Chris)
>- Verify start and length of vma for page alignment (Lionel)
>- Move SQNTL config out (Lionel)
>
>v3: (Chris)
>- Omit redundant checks
>- Return VM_FAULT_SIGBUS is old stream is closed
>- Maintain reference counts to stream in vm_open and vm_close
>- Use switch to identify object to be mapped
>
>Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
>Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
>---
> drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
> drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
> drivers/gpu/drm/i915/i915_perf.c | 196 ++++++++++++++++++++++-
> drivers/gpu/drm/i915/i915_perf_types.h | 17 ++
> include/uapi/drm/i915_drm.h | 32 ++++
> 5 files changed, 245 insertions(+), 4 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
>index b23368529a40..7c4b9b0c334b 100644
>--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
>+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
>@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
> return view;
> }
>
>-static vm_fault_t i915_error_to_vmf_fault(int err)
>+vm_fault_t i915_error_to_vmf_fault(int err)
> {
> switch (err) {
> default:
>diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
>index efee9e0d2508..1190a3a228ea 100644
>--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
>+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
>@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
>
> void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
>
>+vm_fault_t i915_error_to_vmf_fault(int err);
>+
> #endif
>diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
>index 453afeaee0a7..0e9696fc4ab2 100644
>--- a/drivers/gpu/drm/i915/i915_perf.c
>+++ b/drivers/gpu/drm/i915/i915_perf.c
>@@ -192,10 +192,12 @@
> */
>
> #include <linux/anon_inodes.h>
>+#include <linux/mman.h>
> #include <linux/sizes.h>
> #include <linux/uuid.h>
>
> #include "gem/i915_gem_context.h"
>+#include "gem/i915_gem_mman.h"
> #include "gt/intel_engine_pm.h"
> #include "gt/intel_engine_user.h"
> #include "gt/intel_gt.h"
>@@ -434,6 +436,30 @@ static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream)
> return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;
> }
>
>+static u32 gen12_oa_hw_head_read(struct i915_perf_stream *stream)
>+{
>+ struct intel_uncore *uncore = stream->uncore;
>+
>+ return intel_uncore_read(uncore, GEN12_OAG_OAHEADPTR) &
>+ GEN12_OAG_OAHEADPTR_MASK;
>+}
>+
>+static u32 gen8_oa_hw_head_read(struct i915_perf_stream *stream)
>+{
>+ struct intel_uncore *uncore = stream->uncore;
>+
>+ return intel_uncore_read(uncore, GEN8_OAHEADPTR) &
>+ GEN8_OAHEADPTR_MASK;
>+}
>+
>+static u32 gen7_oa_hw_head_read(struct i915_perf_stream *stream)
>+{
>+ struct intel_uncore *uncore = stream->uncore;
>+ u32 oastatus2 = intel_uncore_read(uncore, GEN7_OASTATUS2);
>+
>+ return oastatus2 & GEN7_OASTATUS2_HEAD_MASK;
>+}
>+
> /**
> * oa_buffer_check_unlocked - check for data and update tail ptr state
> * @stream: i915 stream instance
>@@ -1347,6 +1373,15 @@ free_noa_wait(struct i915_perf_stream *stream)
> i915_vma_unpin_and_release(&stream->noa_wait, 0);
> }
>
>+static void
>+free_stream(struct kref *kref)
>+{
>+ struct i915_perf_stream *stream =
>+ container_of(kref, typeof(*stream), refcount);
>+
>+ kfree(stream);
>+}
>+
> static void i915_oa_stream_destroy(struct i915_perf_stream *stream)
> {
> struct i915_perf *perf = stream->perf;
>@@ -2934,6 +2969,7 @@ static int i915_oa_stream_init(struct i915_perf_stream *stream,
> stream->poll_check_timer.function = oa_poll_check_timer_cb;
> init_waitqueue_head(&stream->poll_wq);
> spin_lock_init(&stream->oa_buffer.ptr_lock);
>+ kref_init(&stream->refcount);
>
> return 0;
>
>@@ -3214,6 +3250,69 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
> return ret;
> }
>
>+/**
>+ * i915_perf_oa_buffer_head_tail_locked - head and tail of the OA buffer
>+ * @stream: i915 perf stream
>+ * @arg: pointer to oa buffer head and tail filled by this function.
>+ */
>+static int i915_perf_oa_buffer_head_tail_locked(struct i915_perf_stream *stream,
>+ unsigned long arg)
>+{
>+ struct drm_i915_perf_oa_buffer_head_tail ht;
>+ void __user *output = (void __user *)arg;
>+ u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
>+
>+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
>+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
>+ return -EACCES;
>+ }
>+
>+ if (!output)
>+ return -EINVAL;
>+
>+ memset(&ht, 0, sizeof(ht));
>+
>+ ht.head = stream->perf->ops.oa_hw_head_read(stream) - gtt_offset;
>+ ht.tail = stream->perf->ops.oa_hw_tail_read(stream) - gtt_offset;
>+
>+ if (copy_to_user(output, &ht, sizeof(ht)))
>+ return -EFAULT;
>+
>+ return 0;
>+}
>+
>+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
>+
>+/**
>+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
>+ * @stream: i915 perf stream
>+ * @arg: pointer to oa buffer info filled by this function.
>+ */
>+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
>+ unsigned long arg)
>+{
>+ struct drm_i915_perf_oa_buffer_info info;
>+ void __user *output = (void __user *)arg;
>+
>+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
>+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
>+ return -EACCES;
>+ }
>+
>+ if (!output)
>+ return -EINVAL;
>+
>+ memset(&info, 0, sizeof(info));
>+
>+ info.size = stream->oa_buffer.vma->size;
>+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
>+
>+ if (copy_to_user(output, &info, sizeof(info)))
>+ return -EFAULT;
>+
>+ return 0;
>+}
>+
> /**
> * i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
> * @stream: An i915 perf stream
>@@ -3239,6 +3338,10 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
> return 0;
> case I915_PERF_IOCTL_CONFIG:
> return i915_perf_config_locked(stream, arg);
>+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
>+ return i915_perf_oa_buffer_info_locked(stream, arg);
>+ case I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL:
>+ return i915_perf_oa_buffer_head_tail_locked(stream, arg);
> }
>
> return -EINVAL;
>@@ -3290,8 +3393,6 @@ static void i915_perf_destroy_locked(struct i915_perf_stream *stream)
>
> if (stream->ctx)
> i915_gem_context_put(stream->ctx);
>-
>- kfree(stream);
> }
>
> /**
>@@ -3314,12 +3415,93 @@ static int i915_perf_release(struct inode *inode, struct file *file)
> i915_perf_destroy_locked(stream);
> mutex_unlock(&perf->lock);
>
>+ WRITE_ONCE(stream->closed, true);
>+ unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
>+
> /* Release the reference the perf stream kept on the driver. */
> drm_dev_put(&perf->i915->drm);
>
> return 0;
> }
>
>+static void vm_open_oa(struct vm_area_struct *vma)
>+{
>+ struct i915_perf_stream *stream = vma->vm_private_data;
>+
>+ GEM_BUG_ON(!stream);
>+ kref_get(&stream->refcount);
When user calls mmap, after this call the count is 2 (since kref_init
started off the count with 1).
>+}
>+
>+static void vm_close_oa(struct vm_area_struct *vma)
>+{
>+ struct i915_perf_stream *stream = vma->vm_private_data;
>+
>+ GEM_BUG_ON(!stream);
>+ kref_put(&stream->refcount, free_stream);
When the user closes perf fd or calls unmap, vm_close_oa is called and
refcount goes to 1, so not sure how the refcount goes to 0 so that
free_stream is called. Should I kref_put when closing perf fd also?
>+}
>+
>+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
>+{
>+ struct vm_area_struct *vma = vmf->vma;
>+ struct i915_perf_stream *stream = vma->vm_private_data;
>+ struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
>+ int err;
>+
>+ if (READ_ONCE(stream->closed))
>+ return VM_FAULT_SIGBUS;
>+
>+ err = i915_gem_object_pin_pages(obj);
>+ if (err)
>+ goto out;
>+
>+ err = remap_io_sg(vma,
>+ vma->vm_start, vma->vm_end - vma->vm_start,
>+ obj->mm.pages->sgl, -1);
>+
>+ i915_gem_object_unpin_pages(obj);
>+
>+out:
>+ return i915_error_to_vmf_fault(err);
>+}
>+
>+static const struct vm_operations_struct vm_ops_oa = {
>+ .open = vm_open_oa,
>+ .close = vm_close_oa,
>+ .fault = vm_fault_oa,
>+};
>+
>+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
>+{
>+ struct i915_perf_stream *stream = file->private_data;
>+
>+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
>+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
>+ return -EACCES;
>+ }
>+
>+ switch (vma->vm_pgoff) {
>+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
>+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
>+ return -EINVAL;
>+
>+ if (vma->vm_flags & VM_WRITE)
>+ return -EINVAL;
>+
>+ break;
>+
>+ default:
>+ return -EINVAL;
>+ }
>+
>+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC | VM_MAYSHARE);
>+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
>+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
>+ vma->vm_private_data = stream;
>+ vma->vm_ops = &vm_ops_oa;
>+ vm_open_oa(vma);
I am calling the open explicitly here to get the reference, otherwise I
don't see open being called by anyone/anything.
If user calls mmap multiple times, does he get a unique vma each time?
Do I need to track all of them (and their sizes) and then unmap them
when perf_fd is closed?
>+
>+ return 0;
>+}
>
> static const struct file_operations fops = {
> .owner = THIS_MODULE,
>@@ -3332,6 +3514,7 @@ static const struct file_operations fops = {
> * to handle 32bits compatibility.
> */
> .compat_ioctl = i915_perf_ioctl,
>+ .mmap = i915_perf_mmap,
> };
>
>
>@@ -4260,6 +4443,7 @@ void i915_perf_init(struct drm_i915_private *i915)
> perf->ops.oa_disable = gen7_oa_disable;
> perf->ops.read = gen7_oa_read;
> perf->ops.oa_hw_tail_read = gen7_oa_hw_tail_read;
>+ perf->ops.oa_hw_head_read = gen7_oa_hw_head_read;
>
> perf->oa_formats = hsw_oa_formats;
> } else if (HAS_LOGICAL_RING_CONTEXTS(i915)) {
>@@ -4291,6 +4475,7 @@ void i915_perf_init(struct drm_i915_private *i915)
> perf->ops.enable_metric_set = gen8_enable_metric_set;
> perf->ops.disable_metric_set = gen8_disable_metric_set;
> perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
>+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
>
> if (IS_GEN(i915, 8)) {
> perf->ctx_oactxctrl_offset = 0x120;
>@@ -4318,6 +4503,7 @@ void i915_perf_init(struct drm_i915_private *i915)
> perf->ops.enable_metric_set = gen8_enable_metric_set;
> perf->ops.disable_metric_set = gen10_disable_metric_set;
> perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
>+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
>
> if (IS_GEN(i915, 10)) {
> perf->ctx_oactxctrl_offset = 0x128;
>@@ -4342,6 +4528,7 @@ void i915_perf_init(struct drm_i915_private *i915)
> perf->ops.enable_metric_set = gen12_enable_metric_set;
> perf->ops.disable_metric_set = gen12_disable_metric_set;
> perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
>+ perf->ops.oa_hw_head_read = gen12_oa_hw_head_read;
>
> perf->ctx_flexeu0_offset = 0;
> perf->ctx_oactxctrl_offset = 0x144;
>@@ -4453,8 +4640,11 @@ int i915_perf_ioctl_version(void)
> *
> * 7: Whitelist OA buffer head/tail registers for user to identify the
> * location of triggered reports into the OA buffer.
>+ *
>+ * 8: Added an option to map oa buffer at umd driver level and trigger
>+ * oa reports within oa buffer from command buffer.
> */
>- return 7;
>+ return 8;
> }
>
> #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
>diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
>index a36a455ae336..2efbe35c5fa9 100644
>--- a/drivers/gpu/drm/i915/i915_perf_types.h
>+++ b/drivers/gpu/drm/i915/i915_perf_types.h
>@@ -311,6 +311,18 @@ struct i915_perf_stream {
> * buffer should be checked for available data.
> */
> u64 poll_oa_period;
>+
>+ /**
>+ * @closed: Open or closed state of the stream.
>+ * True if stream is closed.
>+ */
>+ bool closed;
closed is part of the stream itself, so I cannot kfree(stream) until the
refcount goes to 0.
>+
>+ /**
>+ * @refcount: References to the mapped OA buffer managed by this
>+ * stream.
>+ */
>+ struct kref refcount;
> };
>
> /**
>@@ -377,6 +389,11 @@ struct i915_oa_ops {
> * generations.
> */
> u32 (*oa_hw_tail_read)(struct i915_perf_stream *stream);
>+
>+ /**
>+ * @oa_hw_head_read: read the OA head pointer register
>+ */
>+ u32 (*oa_hw_head_read)(struct i915_perf_stream *stream);
> };
>
> struct i915_perf {
>diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
>index 00546062e023..2042f6339182 100644
>--- a/include/uapi/drm/i915_drm.h
>+++ b/include/uapi/drm/i915_drm.h
>@@ -2048,6 +2048,38 @@ struct drm_i915_perf_open_param {
> */
> #define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
>
>+/**
>+ * Returns OA buffer properties to be used with mmap.
>+ *
>+ * This ioctl is available in perf revision 8.
>+ */
>+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IO('i', 0x3)
>+
>+/**
>+ * OA buffer size and offset.
>+ */
>+struct drm_i915_perf_oa_buffer_info {
>+ __u32 size;
>+ __u32 offset;
>+ __u64 reserved[4];
>+};
>+
>+/**
>+ * Returns current position of OA buffer head and tail.
>+ *
>+ * This ioctl is available in perf revision 8.
>+ */
>+#define I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL _IO('i', 0x4)
>+
>+/**
>+ * OA buffer head and tail.
>+ */
>+struct drm_i915_perf_oa_buffer_head_tail {
>+ __u32 head;
>+ __u32 tail;
>+ __u64 reserved[4];
>+};
>+
> /**
> * Common to all i915 perf records
> */
>--
>2.20.1
>
>_______________________________________________
>Intel-gfx mailing list
>Intel-gfx@lists.freedesktop.org
>https://lists.freedesktop.org/mailman/listinfo/intel-gfx
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-21 2:00 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-07-21 2:00 ` Umesh Nerlige Ramappa
2020-07-21 2:17 ` Umesh Nerlige Ramappa
0 siblings, 1 reply; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-21 2:00 UTC (permalink / raw)
To: intel-gfx; +Cc: Chris Wilson
From: Piotr Maciejewski <piotr.maciejewski@intel.com>
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
v3: (Chris)
- Omit redundant checks
- Return VM_FAULT_SIGBUS is old stream is closed
- Maintain reference counts to stream in vm_open and vm_close
- Use switch to identify object to be mapped
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 196 ++++++++++++++++++++++-
drivers/gpu/drm/i915/i915_perf_types.h | 17 ++
include/uapi/drm/i915_drm.h | 32 ++++
5 files changed, 245 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 453afeaee0a7..0e9696fc4ab2 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -434,6 +436,30 @@ static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream)
return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;
}
+static u32 gen12_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+
+ return intel_uncore_read(uncore, GEN12_OAG_OAHEADPTR) &
+ GEN12_OAG_OAHEADPTR_MASK;
+}
+
+static u32 gen8_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+
+ return intel_uncore_read(uncore, GEN8_OAHEADPTR) &
+ GEN8_OAHEADPTR_MASK;
+}
+
+static u32 gen7_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+ u32 oastatus2 = intel_uncore_read(uncore, GEN7_OASTATUS2);
+
+ return oastatus2 & GEN7_OASTATUS2_HEAD_MASK;
+}
+
/**
* oa_buffer_check_unlocked - check for data and update tail ptr state
* @stream: i915 stream instance
@@ -1347,6 +1373,15 @@ free_noa_wait(struct i915_perf_stream *stream)
i915_vma_unpin_and_release(&stream->noa_wait, 0);
}
+static void
+free_stream(struct kref *kref)
+{
+ struct i915_perf_stream *stream =
+ container_of(kref, typeof(*stream), refcount);
+
+ kfree(stream);
+}
+
static void i915_oa_stream_destroy(struct i915_perf_stream *stream)
{
struct i915_perf *perf = stream->perf;
@@ -2934,6 +2969,7 @@ static int i915_oa_stream_init(struct i915_perf_stream *stream,
stream->poll_check_timer.function = oa_poll_check_timer_cb;
init_waitqueue_head(&stream->poll_wq);
spin_lock_init(&stream->oa_buffer.ptr_lock);
+ kref_init(&stream->refcount);
return 0;
@@ -3214,6 +3250,69 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+/**
+ * i915_perf_oa_buffer_head_tail_locked - head and tail of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer head and tail filled by this function.
+ */
+static int i915_perf_oa_buffer_head_tail_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_head_tail ht;
+ void __user *output = (void __user *)arg;
+ u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (!output)
+ return -EINVAL;
+
+ memset(&ht, 0, sizeof(ht));
+
+ ht.head = stream->perf->ops.oa_hw_head_read(stream) - gtt_offset;
+ ht.tail = stream->perf->ops.oa_hw_tail_read(stream) - gtt_offset;
+
+ if (copy_to_user(output, &ht, sizeof(ht)))
+ return -EFAULT;
+
+ return 0;
+}
+
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to access OA buffer info\n");
+ return -EACCES;
+ }
+
+ if (!output)
+ return -EINVAL;
+
+ memset(&info, 0, sizeof(info));
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3239,6 +3338,10 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL:
+ return i915_perf_oa_buffer_head_tail_locked(stream, arg);
}
return -EINVAL;
@@ -3290,8 +3393,6 @@ static void i915_perf_destroy_locked(struct i915_perf_stream *stream)
if (stream->ctx)
i915_gem_context_put(stream->ctx);
-
- kfree(stream);
}
/**
@@ -3314,12 +3415,93 @@ static int i915_perf_release(struct inode *inode, struct file *file)
i915_perf_destroy_locked(stream);
mutex_unlock(&perf->lock);
+ WRITE_ONCE(stream->closed, true);
+ unmap_mapping_range(file->f_mapping, 0, OA_BUFFER_SIZE, 1);
+
/* Release the reference the perf stream kept on the driver. */
drm_dev_put(&perf->i915->drm);
return 0;
}
+static void vm_open_oa(struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = vma->vm_private_data;
+
+ GEM_BUG_ON(!stream);
+ kref_get(&stream->refcount);
+}
+
+static void vm_close_oa(struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = vma->vm_private_data;
+
+ GEM_BUG_ON(!stream);
+ kref_put(&stream->refcount, free_stream);
+}
+
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
+ int err;
+
+ if (READ_ONCE(stream->closed))
+ return VM_FAULT_SIGBUS;
+
+ err = i915_gem_object_pin_pages(obj);
+ if (err)
+ goto out;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ obj->mm.pages->sgl, -1);
+
+ i915_gem_object_unpin_pages(obj);
+
+out:
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .open = vm_open_oa,
+ .close = vm_close_oa,
+ .fault = vm_fault_oa,
+};
+
+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+
+ if (i915_perf_stream_paranoid && !perfmon_capable()) {
+ DRM_DEBUG("Insufficient privileges to map OA buffer\n");
+ return -EACCES;
+ }
+
+ switch (vma->vm_pgoff) {
+ case I915_PERF_OA_BUFFER_MMAP_OFFSET:
+ if (vma->vm_end - vma->vm_start > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ if (vma->vm_flags & VM_WRITE)
+ return -EINVAL;
+
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC | VM_MAYSHARE);
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+ vm_open_oa(vma);
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3332,6 +3514,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4260,6 +4443,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.oa_disable = gen7_oa_disable;
perf->ops.read = gen7_oa_read;
perf->ops.oa_hw_tail_read = gen7_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen7_oa_hw_head_read;
perf->oa_formats = hsw_oa_formats;
} else if (HAS_LOGICAL_RING_CONTEXTS(i915)) {
@@ -4291,6 +4475,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen8_enable_metric_set;
perf->ops.disable_metric_set = gen8_disable_metric_set;
perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
if (IS_GEN(i915, 8)) {
perf->ctx_oactxctrl_offset = 0x120;
@@ -4318,6 +4503,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen8_enable_metric_set;
perf->ops.disable_metric_set = gen10_disable_metric_set;
perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
if (IS_GEN(i915, 10)) {
perf->ctx_oactxctrl_offset = 0x128;
@@ -4342,6 +4528,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen12_enable_metric_set;
perf->ops.disable_metric_set = gen12_disable_metric_set;
perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen12_oa_hw_head_read;
perf->ctx_flexeu0_offset = 0;
perf->ctx_oactxctrl_offset = 0x144;
@@ -4453,8 +4640,11 @@ int i915_perf_ioctl_version(void)
*
* 7: Whitelist OA buffer head/tail registers for user to identify the
* location of triggered reports into the OA buffer.
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
index a36a455ae336..2efbe35c5fa9 100644
--- a/drivers/gpu/drm/i915/i915_perf_types.h
+++ b/drivers/gpu/drm/i915/i915_perf_types.h
@@ -311,6 +311,18 @@ struct i915_perf_stream {
* buffer should be checked for available data.
*/
u64 poll_oa_period;
+
+ /**
+ * @closed: Open or closed state of the stream.
+ * True if stream is closed.
+ */
+ bool closed;
+
+ /**
+ * @refcount: References to the mapped OA buffer managed by this
+ * stream.
+ */
+ struct kref refcount;
};
/**
@@ -377,6 +389,11 @@ struct i915_oa_ops {
* generations.
*/
u32 (*oa_hw_tail_read)(struct i915_perf_stream *stream);
+
+ /**
+ * @oa_hw_head_read: read the OA head pointer register
+ */
+ u32 (*oa_hw_head_read)(struct i915_perf_stream *stream);
};
struct i915_perf {
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..2042f6339182 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,38 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IO('i', 0x3)
+
+/**
+ * OA buffer size and offset.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 size;
+ __u32 offset;
+ __u64 reserved[4];
+};
+
+/**
+ * Returns current position of OA buffer head and tail.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL _IO('i', 0x4)
+
+/**
+ * OA buffer head and tail.
+ */
+struct drm_i915_perf_oa_buffer_head_tail {
+ __u32 head;
+ __u32 tail;
+ __u64 reserved[4];
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply related [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-18 0:04 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-18 11:44 ` kernel test robot
@ 2020-07-20 12:21 ` Chris Wilson
1 sibling, 0 replies; 33+ messages in thread
From: Chris Wilson @ 2020-07-20 12:21 UTC (permalink / raw)
To: Umesh Nerlige Ramappa, intel-gfx
Quoting Umesh Nerlige Ramappa (2020-07-18 01:04:37)
> +static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
> +{
> + struct vm_area_struct *vma = vmf->vma;
> + struct i915_perf_stream *stream = vma->vm_private_data;
> + struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
> + int err;
> +
> + err = i915_gem_object_pin_pages(obj);
> + if (err)
> + goto out;
> +
> + err = remap_io_sg(vma,
> + vma->vm_start, vma->vm_end - vma->vm_start,
> + obj->mm.pages->sgl, -1);
> +
> + i915_gem_object_unpin_pages(obj);
Ok, basics look good (will handle any vma for which we have valid DMA
addresses, and since we control the construction of the vma we know we
can limit it to objects that work via CPU PTE). There is just one small
catch we have to be wary off -- the CPU pte are not holding a reference
to the pages themselves, and so we need to refault if we have to evict.
However! The oa_buffer is perma-pinned so the pages cannot just disappear,
but the mmap itself may outlive the perf-fd. So we need some way to
determine that the vm_fault_oa() is called on an old stream (e..g if
(stream->closed) return VM_FAULT_SIGBUS;), and during stream close to
call unmap_mmaping_range(perf_file->f_mapping, 0, -1);
Since the mmap may live longer than expected, the vm_ops should on
open() take a reference to the stream, and on close() release that
reference.
Now would be a good time to mmap and close the perf-fd in an igt and
verify the mmap is no longer accessible after the close. (To add
complications, you can fork after opening the mmap(perf-fd).)
> +out:
> + return i915_error_to_vmf_fault(err);
> +}
> +
> +static const struct vm_operations_struct vm_ops_oa = {
> + .fault = vm_fault_oa,
> +};
> +
> +int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
> +{
> + struct i915_perf_stream *stream = file->private_data;
> + int len;
> +
> + if (!IS_ALIGNED(vma->vm_start, PAGE_SIZE))
> + return -EINVAL;
> +
> + if (vma->vm_end < vma->vm_start)
> + return -EINVAL;
These strike me as being redundant.
> + len = vma->vm_end - vma->vm_start;
> + if (!IS_ALIGNED(len, PAGE_SIZE) || len > OA_BUFFER_SIZE)
> + return -EINVAL;
> +
> + if (vma->vm_flags & VM_WRITE)
> + return -EINVAL;
> +
> + if (vma->vm_pgoff != I915_PERF_OA_BUFFER_MMAP_OFFSET)
> + return -EINVAL;
I'd throw this is into a switch and do it earlier, so the len and
writable checks can be based on the oa_vma. (Having a switch makes it
clearer that this doesn't have to be a one-off.)
-Chris
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-18 0:04 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
@ 2020-07-18 11:44 ` kernel test robot
2020-07-20 12:21 ` Chris Wilson
1 sibling, 0 replies; 33+ messages in thread
From: kernel test robot @ 2020-07-18 11:44 UTC (permalink / raw)
To: Umesh Nerlige Ramappa, intel-gfx; +Cc: kbuild-all
[-- Attachment #1: Type: text/plain, Size: 1374 bytes --]
Hi Umesh,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on drm-tip/drm-tip next-20200717]
[cannot apply to linus/master v5.8-rc5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Umesh-Nerlige-Ramappa/Allow-privileged-user-to-map-the-OA-buffer/20200718-080929
base: git://anongit.freedesktop.org/drm-intel for-linux-next
config: i386-randconfig-s002-20200717 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-14) 9.3.0
reproduce:
# apt-get install sparse
# sparse version: v0.6.2-49-g707c5017-dirty
# save the attached .config to linux build tree
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
sparse warnings: (new ones prefixed by >>)
>> drivers/gpu/drm/i915/i915_perf.c:3426:5: sparse: sparse: symbol 'i915_perf_mmap' was not declared. Should it be static?
Please review and possibly fold the followup patch.
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 30807 bytes --]
[-- Attachment #3: Type: text/plain, Size: 160 bytes --]
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
^ permalink raw reply [flat|nested] 33+ messages in thread
* Re: [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
@ 2020-07-18 11:44 ` kernel test robot
0 siblings, 0 replies; 33+ messages in thread
From: kernel test robot @ 2020-07-18 11:44 UTC (permalink / raw)
To: kbuild-all
[-- Attachment #1: Type: text/plain, Size: 1410 bytes --]
Hi Umesh,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on drm-tip/drm-tip next-20200717]
[cannot apply to linus/master v5.8-rc5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Umesh-Nerlige-Ramappa/Allow-privileged-user-to-map-the-OA-buffer/20200718-080929
base: git://anongit.freedesktop.org/drm-intel for-linux-next
config: i386-randconfig-s002-20200717 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-14) 9.3.0
reproduce:
# apt-get install sparse
# sparse version: v0.6.2-49-g707c5017-dirty
# save the attached .config to linux build tree
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
sparse warnings: (new ones prefixed by >>)
>> drivers/gpu/drm/i915/i915_perf.c:3426:5: sparse: sparse: symbol 'i915_perf_mmap' was not declared. Should it be static?
Please review and possibly fold the followup patch.
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org
[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 30807 bytes --]
^ permalink raw reply [flat|nested] 33+ messages in thread
* [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query
2020-07-18 0:04 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
@ 2020-07-18 0:04 ` Umesh Nerlige Ramappa
2020-07-18 11:44 ` kernel test robot
2020-07-20 12:21 ` Chris Wilson
0 siblings, 2 replies; 33+ messages in thread
From: Umesh Nerlige Ramappa @ 2020-07-18 0:04 UTC (permalink / raw)
To: intel-gfx
From: Piotr Maciejewski <piotr.maciejewski@intel.com>
i915 used to support time based sampling mode which is good for overall
system monitoring, but is not enough for query mode used to measure a
single draw call or dispatch. Gen9-Gen11 are using current i915 perf
implementation for query, but Gen12+ requires a new approach for query
based on triggered reports within oa buffer.
Triggering reports into the OA buffer is achieved by writing into a
a trigger register. Optionally an unused counter/register is set with a
marker value such that a triggered report can be identified in the OA
buffer. Reports are usually triggered at the start and end of work that
is measured.
Since OA buffer is large and queries can be frequent, an efficient way
to look for triggered reports is required. By knowing the current head
and tail offsets into the OA buffer, it is easier to determine the
locality of the reports of interest.
Current perf OA interface does not expose head/tail information to the
user and it filters out invalid reports before sending data to user.
Also considering limited size of user buffer used during a query,
creating a 1:1 copy of the OA buffer at the user space added undesired
complexity.
The solution was to map the OA buffer to user space provided
(1) that it is accessed from a privileged user.
(2) OA report filtering is not used.
These 2 conditions would satisfy the safety criteria that the current
perf interface addresses.
To enable the query:
- Add an ioctl to expose head and tail to the user
- Add an ioctl to return size and offset of the OA buffer
- Map the OA buffer to the user space
v2:
- Improve commit message (Chris)
- Do not mmap based on gem object filp. Instead, use perf_fd and support
mmap syscall (Chris)
- Pass non-zero offset in mmap to enforce the right object is mapped (Chris)
- Do not expose gpu_address (Chris)
- Verify start and length of vma for page alignment (Lionel)
- Move SQNTL config out (Lionel)
Signed-off-by: Piotr Maciejewski <piotr.maciejewski@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 2 +
drivers/gpu/drm/i915/i915_perf.c | 147 ++++++++++++++++++++++-
drivers/gpu/drm/i915/i915_perf_types.h | 5 +
include/uapi/drm/i915_drm.h | 32 +++++
5 files changed, 186 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index b23368529a40..7c4b9b0c334b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -204,7 +204,7 @@ compute_partial_view(const struct drm_i915_gem_object *obj,
return view;
}
-static vm_fault_t i915_error_to_vmf_fault(int err)
+vm_fault_t i915_error_to_vmf_fault(int err)
{
switch (err) {
default:
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index efee9e0d2508..1190a3a228ea 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -29,4 +29,6 @@ void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj);
+vm_fault_t i915_error_to_vmf_fault(int err);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 15f31c250ca9..e77582761a64 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -192,10 +192,12 @@
*/
#include <linux/anon_inodes.h>
+#include <linux/mman.h>
#include <linux/sizes.h>
#include <linux/uuid.h>
#include "gem/i915_gem_context.h"
+#include "gem/i915_gem_mman.h"
#include "gt/intel_engine_pm.h"
#include "gt/intel_engine_user.h"
#include "gt/intel_gt.h"
@@ -434,6 +436,30 @@ static u32 gen7_oa_hw_tail_read(struct i915_perf_stream *stream)
return oastatus1 & GEN7_OASTATUS1_TAIL_MASK;
}
+static u32 gen12_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+
+ return intel_uncore_read(uncore, GEN12_OAG_OAHEADPTR) &
+ GEN12_OAG_OAHEADPTR_MASK;
+}
+
+static u32 gen8_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+
+ return intel_uncore_read(uncore, GEN8_OAHEADPTR) &
+ GEN8_OAHEADPTR_MASK;
+}
+
+static u32 gen7_oa_hw_head_read(struct i915_perf_stream *stream)
+{
+ struct intel_uncore *uncore = stream->uncore;
+ u32 oastatus2 = intel_uncore_read(uncore, GEN7_OASTATUS2);
+
+ return oastatus2 & GEN7_OASTATUS2_HEAD_MASK;
+}
+
/**
* oa_buffer_check_unlocked - check for data and update tail ptr state
* @stream: i915 stream instance
@@ -3209,6 +3235,59 @@ static long i915_perf_config_locked(struct i915_perf_stream *stream,
return ret;
}
+/**
+ * i915_perf_oa_buffer_head_tail_locked - head and tail of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer head and tail filled by this function.
+ */
+static int i915_perf_oa_buffer_head_tail_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_head_tail ht;
+ void __user *output = (void __user *)arg;
+ u32 gtt_offset = i915_ggtt_offset(stream->oa_buffer.vma);
+
+ if (!output)
+ return -EINVAL;
+
+ memset(&ht, 0, sizeof(ht));
+
+ ht.head = stream->perf->ops.oa_hw_head_read(stream) - gtt_offset;
+ ht.tail = stream->perf->ops.oa_hw_tail_read(stream) - gtt_offset;
+
+ if (copy_to_user(output, &ht, sizeof(ht)))
+ return -EFAULT;
+
+ return 0;
+}
+
+#define I915_PERF_OA_BUFFER_MMAP_OFFSET 1
+
+/**
+ * i915_perf_oa_buffer_info_locked - size and offset of the OA buffer
+ * @stream: i915 perf stream
+ * @arg: pointer to oa buffer info filled by this function.
+ */
+static int i915_perf_oa_buffer_info_locked(struct i915_perf_stream *stream,
+ unsigned long arg)
+{
+ struct drm_i915_perf_oa_buffer_info info;
+ void __user *output = (void __user *)arg;
+
+ if (!output)
+ return -EINVAL;
+
+ memset(&info, 0, sizeof(info));
+
+ info.size = stream->oa_buffer.vma->size;
+ info.offset = I915_PERF_OA_BUFFER_MMAP_OFFSET * PAGE_SIZE;
+
+ if (copy_to_user(output, &info, sizeof(info)))
+ return -EFAULT;
+
+ return 0;
+}
+
/**
* i915_perf_ioctl - support ioctl() usage with i915 perf stream FDs
* @stream: An i915 perf stream
@@ -3234,6 +3313,10 @@ static long i915_perf_ioctl_locked(struct i915_perf_stream *stream,
return 0;
case I915_PERF_IOCTL_CONFIG:
return i915_perf_config_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_INFO:
+ return i915_perf_oa_buffer_info_locked(stream, arg);
+ case I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL:
+ return i915_perf_oa_buffer_head_tail_locked(stream, arg);
}
return -EINVAL;
@@ -3315,6 +3398,60 @@ static int i915_perf_release(struct inode *inode, struct file *file)
return 0;
}
+static vm_fault_t vm_fault_oa(struct vm_fault *vmf)
+{
+ struct vm_area_struct *vma = vmf->vma;
+ struct i915_perf_stream *stream = vma->vm_private_data;
+ struct drm_i915_gem_object *obj = stream->oa_buffer.vma->obj;
+ int err;
+
+ err = i915_gem_object_pin_pages(obj);
+ if (err)
+ goto out;
+
+ err = remap_io_sg(vma,
+ vma->vm_start, vma->vm_end - vma->vm_start,
+ obj->mm.pages->sgl, -1);
+
+ i915_gem_object_unpin_pages(obj);
+
+out:
+ return i915_error_to_vmf_fault(err);
+}
+
+static const struct vm_operations_struct vm_ops_oa = {
+ .fault = vm_fault_oa,
+};
+
+int i915_perf_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct i915_perf_stream *stream = file->private_data;
+ int len;
+
+ if (!IS_ALIGNED(vma->vm_start, PAGE_SIZE))
+ return -EINVAL;
+
+ if (vma->vm_end < vma->vm_start)
+ return -EINVAL;
+
+ len = vma->vm_end - vma->vm_start;
+ if (!IS_ALIGNED(len, PAGE_SIZE) || len > OA_BUFFER_SIZE)
+ return -EINVAL;
+
+ if (vma->vm_flags & VM_WRITE)
+ return -EINVAL;
+
+ if (vma->vm_pgoff != I915_PERF_OA_BUFFER_MMAP_OFFSET)
+ return -EINVAL;
+
+ vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC | VM_MAYSHARE);
+ vma->vm_flags |= VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
+ vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+ vma->vm_private_data = stream;
+ vma->vm_ops = &vm_ops_oa;
+
+ return 0;
+}
static const struct file_operations fops = {
.owner = THIS_MODULE,
@@ -3327,6 +3464,7 @@ static const struct file_operations fops = {
* to handle 32bits compatibility.
*/
.compat_ioctl = i915_perf_ioctl,
+ .mmap = i915_perf_mmap,
};
@@ -4255,6 +4393,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.oa_disable = gen7_oa_disable;
perf->ops.read = gen7_oa_read;
perf->ops.oa_hw_tail_read = gen7_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen7_oa_hw_head_read;
perf->oa_formats = hsw_oa_formats;
} else if (HAS_LOGICAL_RING_CONTEXTS(i915)) {
@@ -4286,6 +4425,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen8_enable_metric_set;
perf->ops.disable_metric_set = gen8_disable_metric_set;
perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
if (IS_GEN(i915, 8)) {
perf->ctx_oactxctrl_offset = 0x120;
@@ -4313,6 +4453,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen8_enable_metric_set;
perf->ops.disable_metric_set = gen10_disable_metric_set;
perf->ops.oa_hw_tail_read = gen8_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen8_oa_hw_head_read;
if (IS_GEN(i915, 10)) {
perf->ctx_oactxctrl_offset = 0x128;
@@ -4337,6 +4478,7 @@ void i915_perf_init(struct drm_i915_private *i915)
perf->ops.enable_metric_set = gen12_enable_metric_set;
perf->ops.disable_metric_set = gen12_disable_metric_set;
perf->ops.oa_hw_tail_read = gen12_oa_hw_tail_read;
+ perf->ops.oa_hw_head_read = gen12_oa_hw_head_read;
perf->ctx_flexeu0_offset = 0;
perf->ctx_oactxctrl_offset = 0x144;
@@ -4448,8 +4590,11 @@ int i915_perf_ioctl_version(void)
*
* 7: Whitelist OA buffer head/tail registers for user to identify the
* location of triggered reports into the OA buffer.
+ *
+ * 8: Added an option to map oa buffer at umd driver level and trigger
+ * oa reports within oa buffer from command buffer.
*/
- return 7;
+ return 8;
}
#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
diff --git a/drivers/gpu/drm/i915/i915_perf_types.h b/drivers/gpu/drm/i915/i915_perf_types.h
index a36a455ae336..579f34e6fdd8 100644
--- a/drivers/gpu/drm/i915/i915_perf_types.h
+++ b/drivers/gpu/drm/i915/i915_perf_types.h
@@ -377,6 +377,11 @@ struct i915_oa_ops {
* generations.
*/
u32 (*oa_hw_tail_read)(struct i915_perf_stream *stream);
+
+ /**
+ * @oa_hw_head_read: read the OA head pointer register
+ */
+ u32 (*oa_hw_head_read)(struct i915_perf_stream *stream);
};
struct i915_perf {
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 00546062e023..2042f6339182 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -2048,6 +2048,38 @@ struct drm_i915_perf_open_param {
*/
#define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
+/**
+ * Returns OA buffer properties to be used with mmap.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IO('i', 0x3)
+
+/**
+ * OA buffer size and offset.
+ */
+struct drm_i915_perf_oa_buffer_info {
+ __u32 size;
+ __u32 offset;
+ __u64 reserved[4];
+};
+
+/**
+ * Returns current position of OA buffer head and tail.
+ *
+ * This ioctl is available in perf revision 8.
+ */
+#define I915_PERF_IOCTL_GET_OA_BUFFER_HEAD_TAIL _IO('i', 0x4)
+
+/**
+ * OA buffer head and tail.
+ */
+struct drm_i915_perf_oa_buffer_head_tail {
+ __u32 head;
+ __u32 tail;
+ __u64 reserved[4];
+};
+
/**
* Common to all i915 perf records
*/
--
2.20.1
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^ permalink raw reply related [flat|nested] 33+ messages in thread
end of thread, other threads:[~2020-08-20 18:02 UTC | newest]
Thread overview: 33+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-22 5:55 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 1/4] drm/i915/perf: Ensure observation logic is not clock gated Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 2/4] drm/i915/perf: Whitelist OA report trigger registers Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 3/4] drm/i915/perf: Whitelist OA counter and buffer registers Umesh Nerlige Ramappa
2020-07-22 5:55 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-23 9:31 ` Lionel Landwerlin
2020-07-23 23:48 ` Umesh Nerlige Ramappa
2020-07-22 6:27 ` [Intel-gfx] ✗ Fi.CI.SPARSE: warning for Allow privileged user to map the OA buffer (rev4) Patchwork
2020-07-22 6:48 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork
-- strict thread matches above, loose matches on Subject: below --
2020-08-20 18:01 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-08-20 18:02 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-08-04 17:11 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-08-04 17:11 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-31 23:58 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-31 23:58 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-31 14:46 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-31 14:46 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-31 14:55 ` Chris Wilson
2020-07-31 6:07 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-31 6:07 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-31 9:35 ` Chris Wilson
2020-07-30 23:02 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-30 23:02 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-24 0:18 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-24 0:19 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-24 12:42 ` Chris Wilson
2020-07-24 16:29 ` Umesh Nerlige Ramappa
2020-07-24 16:34 ` Chris Wilson
2020-07-24 18:47 ` Umesh Nerlige Ramappa
2020-07-24 18:55 ` Chris Wilson
2020-07-24 19:35 ` Umesh Nerlige Ramappa
2020-07-24 19:46 ` Chris Wilson
2020-07-24 22:05 ` Umesh Nerlige Ramappa
2020-07-21 2:00 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-21 2:00 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-21 2:17 ` Umesh Nerlige Ramappa
2020-07-21 8:52 ` Chris Wilson
2020-07-18 0:04 [Intel-gfx] [PATCH 0/4] Allow privileged user to map the OA buffer Umesh Nerlige Ramappa
2020-07-18 0:04 ` [Intel-gfx] [PATCH 4/4] drm/i915/perf: Map OA buffer to user space for gen12 performance query Umesh Nerlige Ramappa
2020-07-18 11:44 ` kernel test robot
2020-07-18 11:44 ` kernel test robot
2020-07-20 12:21 ` Chris Wilson
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