kvm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
@ 2020-07-31  7:42 Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 01/10] arm64: microbench: get correct ipi received num Jingyi Wang
                   ` (12 more replies)
  0 siblings, 13 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

With the development of arm gic architecture, we think it will be useful
to add some performance test in kut to measure the cost of interrupts.
In this series, we add GICv4.1 support for ipi latency test and
implement LPI/vtimer latency test.

This series of patches has been tested on GICv4.1 supported hardware.

Note:
Based on patch "arm/arm64: timer: Extract irqs at setup time",
https://www.spinics.net/lists/kvm-arm/msg41425.html

* From v2:
  - Code and commit message cleanup
  - Clear nr_ipi_received before ipi_exec() thanks for Tao Zeng's review
  - rebase the patch "Add vtimer latency test" on Andrew's patch
  - Add test->post() to get actual PPI latency

* From v1:
  - Fix spelling mistake
  - Use the existing interface to inject hw sgi to simply the logic
  - Add two separate patches to limit the running times and time cost
    of each individual micro-bench test

Jingyi Wang (10):
  arm64: microbench: get correct ipi received num
  arm64: microbench: Generalize ipi test names
  arm64: microbench: gic: Add ipi latency test for gicv4.1 support kvm
  arm64: its: Handle its command queue wrapping
  arm64: microbench: its: Add LPI latency test
  arm64: microbench: Allow each test to specify its running times
  arm64: microbench: Add time limit for each individual test
  arm64: microbench: Add vtimer latency test
  arm64: microbench: Add test->post() to further process test results
  arm64: microbench: Add timer_post() to get actual PPI latency

 arm/micro-bench.c          | 256 ++++++++++++++++++++++++++++++-------
 lib/arm/asm/gic-v3.h       |   3 +
 lib/arm/asm/gic.h          |   1 +
 lib/arm64/gic-v3-its-cmd.c |   3 +-
 4 files changed, 219 insertions(+), 44 deletions(-)

-- 
2.19.1



^ permalink raw reply	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 01/10] arm64: microbench: get correct ipi received num
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 02/10] arm64: microbench: Generalize ipi test names Jingyi Wang
                   ` (11 subsequent siblings)
  12 siblings, 0 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

If ipi_exec() fails because of timeout, we shouldn't increase
the number of ipi received.

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
 arm/micro-bench.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index 4612f41..794dfac 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -103,7 +103,9 @@ static void ipi_exec(void)
 	while (!ipi_received && tries--)
 		cpu_relax();
 
-	++received;
+	if (ipi_received)
+		++received;
+
 	assert_msg(ipi_received, "failed to receive IPI in time, but received %d successfully\n", received);
 }
 
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 02/10] arm64: microbench: Generalize ipi test names
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 01/10] arm64: microbench: get correct ipi received num Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 03/10] arm64: microbench: gic: Add ipi latency test for gicv4.1 support kvm Jingyi Wang
                   ` (10 subsequent siblings)
  12 siblings, 0 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

Later patches will use these functions for gic(ipi/lpi/timer) tests.

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
 arm/micro-bench.c | 39 ++++++++++++++++++++++-----------------
 1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index 794dfac..fc4d356 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -25,24 +25,24 @@
 
 static u32 cntfrq;
 
-static volatile bool ipi_ready, ipi_received;
+static volatile bool irq_ready, irq_received;
 static void *vgic_dist_base;
 static void (*write_eoir)(u32 irqstat);
 
-static void ipi_irq_handler(struct pt_regs *regs)
+static void gic_irq_handler(struct pt_regs *regs)
 {
-	ipi_ready = false;
-	ipi_received = true;
+	irq_ready = false;
+	irq_received = true;
 	gic_write_eoir(gic_read_iar());
-	ipi_ready = true;
+	irq_ready = true;
 }
 
-static void ipi_secondary_entry(void *data)
+static void gic_secondary_entry(void *data)
 {
-	install_irq_handler(EL1H_IRQ, ipi_irq_handler);
+	install_irq_handler(EL1H_IRQ, gic_irq_handler);
 	gic_enable_defaults();
 	local_irq_enable();
-	ipi_ready = true;
+	irq_ready = true;
 	while (true)
 		cpu_relax();
 }
@@ -72,9 +72,9 @@ static bool test_init(void)
 		break;
 	}
 
-	ipi_ready = false;
+	irq_ready = false;
 	gic_enable_defaults();
-	on_cpu_async(1, ipi_secondary_entry, NULL);
+	on_cpu_async(1, gic_secondary_entry, NULL);
 
 	cntfrq = get_cntfrq();
 	printf("Timer Frequency %d Hz (Output in microseconds)\n", cntfrq);
@@ -82,13 +82,18 @@ static bool test_init(void)
 	return true;
 }
 
-static void ipi_prep(void)
+static void gic_prep_common(void)
 {
 	unsigned tries = 1 << 28;
 
-	while (!ipi_ready && tries--)
+	while (!irq_ready && tries--)
 		cpu_relax();
-	assert(ipi_ready);
+	assert(irq_ready);
+}
+
+static void ipi_prep(void)
+{
+	gic_prep_common();
 }
 
 static void ipi_exec(void)
@@ -96,17 +101,17 @@ static void ipi_exec(void)
 	unsigned tries = 1 << 28;
 	static int received = 0;
 
-	ipi_received = false;
+	irq_received = false;
 
 	gic_ipi_send_single(1, 1);
 
-	while (!ipi_received && tries--)
+	while (!irq_received && tries--)
 		cpu_relax();
 
-	if (ipi_received)
+	if (irq_received)
 		++received;
 
-	assert_msg(ipi_received, "failed to receive IPI in time, but received %d successfully\n", received);
+	assert_msg(irq_received, "failed to receive IPI in time, but received %d successfully\n", received);
 }
 
 static void hvc_exec(void)
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 03/10] arm64: microbench: gic: Add ipi latency test for gicv4.1 support kvm
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 01/10] arm64: microbench: get correct ipi received num Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 02/10] arm64: microbench: Generalize ipi test names Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 04/10] arm64: its: Handle its command queue wrapping Jingyi Wang
                   ` (9 subsequent siblings)
  12 siblings, 0 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

If gicv4.1(sgi hardware injection) is supported in kvm, we test ipi
injection via hw/sw way separately.

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
---
 arm/micro-bench.c    | 62 ++++++++++++++++++++++++++++++++++++++------
 lib/arm/asm/gic-v3.h |  3 +++
 lib/arm/asm/gic.h    |  1 +
 3 files changed, 58 insertions(+), 8 deletions(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index fc4d356..f8314db 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -26,6 +26,8 @@
 static u32 cntfrq;
 
 static volatile bool irq_ready, irq_received;
+static int nr_ipi_received;
+
 static void *vgic_dist_base;
 static void (*write_eoir)(u32 irqstat);
 
@@ -91,15 +93,55 @@ static void gic_prep_common(void)
 	assert(irq_ready);
 }
 
-static void ipi_prep(void)
+static bool ipi_prep(void)
+{
+	u32 val;
+
+	val = readl(vgic_dist_base + GICD_CTLR);
+	if (readl(vgic_dist_base + GICD_TYPER2) & GICD_TYPER2_nASSGIcap) {
+		/* nASSGIreq can be changed only when GICD is disabled */
+		val &= ~GICD_CTLR_ENABLE_G1A;
+		val &= ~GICD_CTLR_nASSGIreq;
+		writel(val, vgic_dist_base + GICD_CTLR);
+		gicv3_dist_wait_for_rwp();
+
+		val |= GICD_CTLR_ENABLE_G1A;
+		writel(val, vgic_dist_base + GICD_CTLR);
+		gicv3_dist_wait_for_rwp();
+	}
+
+	nr_ipi_received = 0;
+	gic_prep_common();
+	return true;
+}
+
+static bool ipi_hw_prep(void)
 {
+	u32 val;
+
+	val = readl(vgic_dist_base + GICD_CTLR);
+	if (readl(vgic_dist_base + GICD_TYPER2) & GICD_TYPER2_nASSGIcap) {
+		/* nASSGIreq can be changed only when GICD is disabled */
+		val &= ~GICD_CTLR_ENABLE_G1A;
+		val |= GICD_CTLR_nASSGIreq;
+		writel(val, vgic_dist_base + GICD_CTLR);
+		gicv3_dist_wait_for_rwp();
+
+		val |= GICD_CTLR_ENABLE_G1A;
+		writel(val, vgic_dist_base + GICD_CTLR);
+		gicv3_dist_wait_for_rwp();
+	} else {
+		return false;
+	}
+
+	nr_ipi_received = 0;
 	gic_prep_common();
+	return true;
 }
 
 static void ipi_exec(void)
 {
 	unsigned tries = 1 << 28;
-	static int received = 0;
 
 	irq_received = false;
 
@@ -109,9 +151,9 @@ static void ipi_exec(void)
 		cpu_relax();
 
 	if (irq_received)
-		++received;
+		++nr_ipi_received;
 
-	assert_msg(irq_received, "failed to receive IPI in time, but received %d successfully\n", received);
+	assert_msg(irq_received, "failed to receive IPI in time, but received %d successfully\n", nr_ipi_received);
 }
 
 static void hvc_exec(void)
@@ -147,7 +189,7 @@ static void eoi_exec(void)
 
 struct exit_test {
 	const char *name;
-	void (*prep)(void);
+	bool (*prep)(void);
 	void (*exec)(void);
 	bool run;
 };
@@ -158,6 +200,7 @@ static struct exit_test tests[] = {
 	{"mmio_read_vgic",	NULL,		mmio_read_vgic_exec,	true},
 	{"eoi",			NULL,		eoi_exec,		true},
 	{"ipi",			ipi_prep,	ipi_exec,		true},
+	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		true},
 };
 
 struct ns_time {
@@ -181,9 +224,12 @@ static void loop_test(struct exit_test *test)
 	uint64_t start, end, total_ticks, ntimes = NTIMES;
 	struct ns_time total_ns, avg_ns;
 
-	if (test->prep)
-		test->prep();
-
+	if (test->prep) {
+		if(!test->prep()) {
+			printf("%s test skipped\n", test->name);
+			return;
+		}
+	}
 	isb();
 	start = read_sysreg(cntpct_el0);
 	while (ntimes--)
diff --git a/lib/arm/asm/gic-v3.h b/lib/arm/asm/gic-v3.h
index cb72922..b4ce130 100644
--- a/lib/arm/asm/gic-v3.h
+++ b/lib/arm/asm/gic-v3.h
@@ -20,10 +20,13 @@
  */
 #define GICD_CTLR			0x0000
 #define GICD_CTLR_RWP			(1U << 31)
+#define GICD_CTLR_nASSGIreq		(1U << 8)
 #define GICD_CTLR_ARE_NS		(1U << 4)
 #define GICD_CTLR_ENABLE_G1A		(1U << 1)
 #define GICD_CTLR_ENABLE_G1		(1U << 0)
 
+#define GICD_TYPER2_nASSGIcap		(1U << 8)
+
 /* Re-Distributor registers, offsets from RD_base */
 #define GICR_TYPER			0x0008
 
diff --git a/lib/arm/asm/gic.h b/lib/arm/asm/gic.h
index 38e79b2..1898400 100644
--- a/lib/arm/asm/gic.h
+++ b/lib/arm/asm/gic.h
@@ -13,6 +13,7 @@
 #define GICD_CTLR			0x0000
 #define GICD_TYPER			0x0004
 #define GICD_IIDR			0x0008
+#define GICD_TYPER2			0x000C
 #define GICD_IGROUPR			0x0080
 #define GICD_ISENABLER			0x0100
 #define GICD_ICENABLER			0x0180
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 04/10] arm64: its: Handle its command queue wrapping
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (2 preceding siblings ...)
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 03/10] arm64: microbench: gic: Add ipi latency test for gicv4.1 support kvm Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 05/10] arm64: microbench: its: Add LPI latency test Jingyi Wang
                   ` (8 subsequent siblings)
  12 siblings, 0 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

Because micro-bench may send a large number of ITS commands, we
should handle ITS command queue wrapping as kernel instead of just
failing the test.

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
 lib/arm64/gic-v3-its-cmd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/arm64/gic-v3-its-cmd.c b/lib/arm64/gic-v3-its-cmd.c
index 2c208d1..34574f7 100644
--- a/lib/arm64/gic-v3-its-cmd.c
+++ b/lib/arm64/gic-v3-its-cmd.c
@@ -164,8 +164,9 @@ static struct its_cmd_block *its_allocate_entry(void)
 {
 	struct its_cmd_block *cmd;
 
-	assert((u64)its_data.cmd_write < (u64)its_data.cmd_base + SZ_64K);
 	cmd = its_data.cmd_write++;
+	if ((u64)its_data.cmd_write  == (u64)its_data.cmd_base + SZ_64K)
+		its_data.cmd_write = its_data.cmd_base;
 	return cmd;
 }
 
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 05/10] arm64: microbench: its: Add LPI latency test
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (3 preceding siblings ...)
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 04/10] arm64: its: Handle its command queue wrapping Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 06/10] arm64: microbench: Allow each test to specify its running times Jingyi Wang
                   ` (7 subsequent siblings)
  12 siblings, 0 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

Triggers LPIs through the INT command and test the latency.
Mostly inherited form commit 0ef02cd6cbaa(arm/arm64: ITS: INT
functional tests).

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
 arm/micro-bench.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index f8314db..82f3c07 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -20,6 +20,7 @@
  */
 #include <libcflat.h>
 #include <asm/gic.h>
+#include <asm/gic-v3-its.h>
 
 #define NTIMES (1U << 16)
 
@@ -156,6 +157,48 @@ static void ipi_exec(void)
 	assert_msg(irq_received, "failed to receive IPI in time, but received %d successfully\n", nr_ipi_received);
 }
 
+static bool lpi_prep(void)
+{
+	struct its_collection *col1;
+	struct its_device *dev2;
+
+	if (!gicv3_its_base())
+		return false;
+
+	its_enable_defaults();
+	dev2 = its_create_device(2 /* dev id */, 8 /* nb_ites */);
+	col1 = its_create_collection(1 /* col id */, 1 /* target PE */);
+	gicv3_lpi_set_config(8199, LPI_PROP_DEFAULT);
+
+	its_send_mapd_nv(dev2, true);
+	its_send_mapc_nv(col1, true);
+	its_send_invall_nv(col1);
+	its_send_mapti_nv(dev2, 8199 /* lpi id */, 20 /* event id */, col1);
+
+	gic_prep_common();
+	return true;
+}
+
+static void lpi_exec(void)
+{
+	struct its_device *dev2;
+	unsigned tries = 1 << 28;
+	static int received = 0;
+
+	irq_received = false;
+
+	dev2 = its_get_device(2);
+	its_send_int_nv(dev2, 20);
+
+	while (!irq_received && tries--)
+		cpu_relax();
+
+	if (irq_received)
+		++received;
+
+	assert_msg(irq_received, "failed to receive LPI in time, but received %d successfully\n", received);
+}
+
 static void hvc_exec(void)
 {
 	asm volatile("mov w0, #0x4b000000; hvc #0" ::: "w0");
@@ -201,6 +244,7 @@ static struct exit_test tests[] = {
 	{"eoi",			NULL,		eoi_exec,		true},
 	{"ipi",			ipi_prep,	ipi_exec,		true},
 	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		true},
+	{"lpi",			lpi_prep,	lpi_exec,		true},
 };
 
 struct ns_time {
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 06/10] arm64: microbench: Allow each test to specify its running times
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (4 preceding siblings ...)
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 05/10] arm64: microbench: its: Add LPI latency test Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 07/10] arm64: microbench: Add time limit for each individual test Jingyi Wang
                   ` (6 subsequent siblings)
  12 siblings, 0 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

For some test in micro-bench can be time consuming, we add a
micro-bench test parameter to allow each individual test to specify
its running times.

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
 arm/micro-bench.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index 82f3c07..93bd855 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -22,8 +22,6 @@
 #include <asm/gic.h>
 #include <asm/gic-v3-its.h>
 
-#define NTIMES (1U << 16)
-
 static u32 cntfrq;
 
 static volatile bool irq_ready, irq_received;
@@ -234,17 +232,18 @@ struct exit_test {
 	const char *name;
 	bool (*prep)(void);
 	void (*exec)(void);
+	u32 times;
 	bool run;
 };
 
 static struct exit_test tests[] = {
-	{"hvc",			NULL,		hvc_exec,		true},
-	{"mmio_read_user",	NULL,		mmio_read_user_exec,	true},
-	{"mmio_read_vgic",	NULL,		mmio_read_vgic_exec,	true},
-	{"eoi",			NULL,		eoi_exec,		true},
-	{"ipi",			ipi_prep,	ipi_exec,		true},
-	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		true},
-	{"lpi",			lpi_prep,	lpi_exec,		true},
+	{"hvc",			NULL,		hvc_exec,		65536,		true},
+	{"mmio_read_user",	NULL,		mmio_read_user_exec,	65536,		true},
+	{"mmio_read_vgic",	NULL,		mmio_read_vgic_exec,	65536,		true},
+	{"eoi",			NULL,		eoi_exec,		65536,		true},
+	{"ipi",			ipi_prep,	ipi_exec,		65536,		true},
+	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		65536,		true},
+	{"lpi",			lpi_prep,	lpi_exec,		65536,		true},
 };
 
 struct ns_time {
@@ -265,7 +264,7 @@ static void ticks_to_ns_time(uint64_t ticks, struct ns_time *ns_time)
 
 static void loop_test(struct exit_test *test)
 {
-	uint64_t start, end, total_ticks, ntimes = NTIMES;
+	uint64_t start, end, total_ticks, ntimes = 0;
 	struct ns_time total_ns, avg_ns;
 
 	if (test->prep) {
@@ -276,15 +275,17 @@ static void loop_test(struct exit_test *test)
 	}
 	isb();
 	start = read_sysreg(cntpct_el0);
-	while (ntimes--)
+	while (ntimes < test->times) {
 		test->exec();
+		ntimes++;
+	}
 	isb();
 	end = read_sysreg(cntpct_el0);
 
 	total_ticks = end - start;
 	ticks_to_ns_time(total_ticks, &total_ns);
-	avg_ns.ns = total_ns.ns / NTIMES;
-	avg_ns.ns_frac = total_ns.ns_frac / NTIMES;
+	avg_ns.ns = total_ns.ns / ntimes;
+	avg_ns.ns_frac = total_ns.ns_frac / ntimes;
 
 	printf("%-30s%15" PRId64 ".%-15" PRId64 "%15" PRId64 ".%-15" PRId64 "\n",
 		test->name, total_ns.ns, total_ns.ns_frac, avg_ns.ns, avg_ns.ns_frac);
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 07/10] arm64: microbench: Add time limit for each individual test
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (5 preceding siblings ...)
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 06/10] arm64: microbench: Allow each test to specify its running times Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-08-01 16:13   ` Andrew Jones
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 08/10] arm64: microbench: Add vtimer latency test Jingyi Wang
                   ` (5 subsequent siblings)
  12 siblings, 1 reply; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

Besides using separate running times parameter, we add time limit
for loop_test to make sure each test should be done in a certain
time(5 sec here).

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
 arm/micro-bench.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index 93bd855..09d9d53 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -22,6 +22,7 @@
 #include <asm/gic.h>
 #include <asm/gic-v3-its.h>
 
+#define NS_5_SECONDS (5 * 1000 * 1000 * 1000UL)
 static u32 cntfrq;
 
 static volatile bool irq_ready, irq_received;
@@ -267,23 +268,26 @@ static void loop_test(struct exit_test *test)
 	uint64_t start, end, total_ticks, ntimes = 0;
 	struct ns_time total_ns, avg_ns;
 
+	total_ticks = 0;
 	if (test->prep) {
 		if(!test->prep()) {
 			printf("%s test skipped\n", test->name);
 			return;
 		}
 	}
-	isb();
-	start = read_sysreg(cntpct_el0);
-	while (ntimes < test->times) {
+
+	while (ntimes < test->times && total_ns.ns < NS_5_SECONDS) {
+		isb();
+		start = read_sysreg(cntpct_el0);
 		test->exec();
+		isb();
+		end = read_sysreg(cntpct_el0);
+
 		ntimes++;
+		total_ticks += (end - start);
+		ticks_to_ns_time(total_ticks, &total_ns);
 	}
-	isb();
-	end = read_sysreg(cntpct_el0);
 
-	total_ticks = end - start;
-	ticks_to_ns_time(total_ticks, &total_ns);
 	avg_ns.ns = total_ns.ns / ntimes;
 	avg_ns.ns_frac = total_ns.ns_frac / ntimes;
 
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 08/10] arm64: microbench: Add vtimer latency test
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (6 preceding siblings ...)
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 07/10] arm64: microbench: Add time limit for each individual test Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-08-01 16:22   ` Andrew Jones
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 09/10] arm64: microbench: Add test->post() to further process test results Jingyi Wang
                   ` (4 subsequent siblings)
  12 siblings, 1 reply; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

Trigger PPIs by setting up a 10msec timer and test the latency.

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
---
 arm/micro-bench.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 52 insertions(+), 1 deletion(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index 09d9d53..1e1bde5 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -21,8 +21,10 @@
 #include <libcflat.h>
 #include <asm/gic.h>
 #include <asm/gic-v3-its.h>
+#include <asm/timer.h>
 
 #define NS_5_SECONDS (5 * 1000 * 1000 * 1000UL)
+
 static u32 cntfrq;
 
 static volatile bool irq_ready, irq_received;
@@ -33,9 +35,16 @@ static void (*write_eoir)(u32 irqstat);
 
 static void gic_irq_handler(struct pt_regs *regs)
 {
+	u32 irqstat = gic_read_iar();
 	irq_ready = false;
 	irq_received = true;
-	gic_write_eoir(gic_read_iar());
+	gic_write_eoir(irqstat);
+
+	if (irqstat == PPI(TIMER_VTIMER_IRQ)) {
+		write_sysreg((ARCH_TIMER_CTL_IMASK | ARCH_TIMER_CTL_ENABLE),
+			     cntv_ctl_el0);
+		isb();
+	}
 	irq_ready = true;
 }
 
@@ -198,6 +207,47 @@ static void lpi_exec(void)
 	assert_msg(irq_received, "failed to receive LPI in time, but received %d successfully\n", received);
 }
 
+static bool timer_prep(void)
+{
+	static void *gic_isenabler;
+
+	gic_enable_defaults();
+	install_irq_handler(EL1H_IRQ, gic_irq_handler);
+	local_irq_enable();
+
+	gic_isenabler = gicv3_sgi_base() + GICR_ISENABLER0;
+	writel(1 << PPI(TIMER_VTIMER_IRQ), gic_isenabler);
+	write_sysreg(ARCH_TIMER_CTL_ENABLE, cntv_ctl_el0);
+	isb();
+
+	gic_prep_common();
+	return true;
+}
+
+static void timer_exec(void)
+{
+	u64 before_timer;
+	u64 timer_10ms;
+	unsigned tries = 1 << 28;
+	static int received = 0;
+
+	irq_received = false;
+
+	before_timer = read_sysreg(cntvct_el0);
+	timer_10ms = cntfrq / 100;
+	write_sysreg(before_timer + timer_10ms, cntv_cval_el0);
+	write_sysreg(ARCH_TIMER_CTL_ENABLE, cntv_ctl_el0);
+	isb();
+
+	while (!irq_received && tries--)
+		cpu_relax();
+
+	if (irq_received)
+		++received;
+
+	assert_msg(irq_received, "failed to receive PPI in time, but received %d successfully\n", received);
+}
+
 static void hvc_exec(void)
 {
 	asm volatile("mov w0, #0x4b000000; hvc #0" ::: "w0");
@@ -245,6 +295,7 @@ static struct exit_test tests[] = {
 	{"ipi",			ipi_prep,	ipi_exec,		65536,		true},
 	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		65536,		true},
 	{"lpi",			lpi_prep,	lpi_exec,		65536,		true},
+	{"timer_10ms",		timer_prep,	timer_exec,		256,		true},
 };
 
 struct ns_time {
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 09/10] arm64: microbench: Add test->post() to further process test results
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (7 preceding siblings ...)
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 08/10] arm64: microbench: Add vtimer latency test Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-08-01 17:03   ` Andrew Jones
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 10/10] arm64: microbench: Add timer_post() to get actual PPI latency Jingyi Wang
                   ` (3 subsequent siblings)
  12 siblings, 1 reply; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

Under certain circumstances, we need to further process microbench
test results, so we add test->post() in the microbench framework,
later patch will use that.

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
---
 arm/micro-bench.c | 31 ++++++++++++++++++-------------
 1 file changed, 18 insertions(+), 13 deletions(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index 1e1bde5..4680ba4 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -33,6 +33,12 @@ static int nr_ipi_received;
 static void *vgic_dist_base;
 static void (*write_eoir)(u32 irqstat);
 
+struct ns_time {
+	uint64_t ns;
+	uint64_t ns_frac;
+};
+static void ticks_to_ns_time(uint64_t ticks, struct ns_time *ns_time);
+
 static void gic_irq_handler(struct pt_regs *regs)
 {
 	u32 irqstat = gic_read_iar();
@@ -283,24 +289,20 @@ struct exit_test {
 	const char *name;
 	bool (*prep)(void);
 	void (*exec)(void);
+	void (*post)(uint64_t, uint64_t, struct ns_time*);
 	u32 times;
 	bool run;
 };
 
 static struct exit_test tests[] = {
-	{"hvc",			NULL,		hvc_exec,		65536,		true},
-	{"mmio_read_user",	NULL,		mmio_read_user_exec,	65536,		true},
-	{"mmio_read_vgic",	NULL,		mmio_read_vgic_exec,	65536,		true},
-	{"eoi",			NULL,		eoi_exec,		65536,		true},
-	{"ipi",			ipi_prep,	ipi_exec,		65536,		true},
-	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		65536,		true},
-	{"lpi",			lpi_prep,	lpi_exec,		65536,		true},
-	{"timer_10ms",		timer_prep,	timer_exec,		256,		true},
-};
-
-struct ns_time {
-	uint64_t ns;
-	uint64_t ns_frac;
+	{"hvc",			NULL,		hvc_exec,		NULL,		65536,		true},
+	{"mmio_read_user",	NULL,		mmio_read_user_exec,	NULL,		65536,		true},
+	{"mmio_read_vgic",	NULL,		mmio_read_vgic_exec,	NULL,		65536,		true},
+	{"eoi",			NULL,		eoi_exec,		NULL,		65536,		true},
+	{"ipi",			ipi_prep,	ipi_exec,		NULL,		65536,		true},
+	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		NULL,		65536,		true},
+	{"lpi",			lpi_prep,	lpi_exec,		NULL,		65536,		true},
+	{"timer_10ms",		timer_prep,	timer_exec,		NULL,		256,		true},
 };
 
 #define PS_PER_SEC (1000 * 1000 * 1000 * 1000UL)
@@ -339,6 +341,9 @@ static void loop_test(struct exit_test *test)
 		ticks_to_ns_time(total_ticks, &total_ns);
 	}
 
+	if (test->post)
+		test->post(total_ticks, ntimes, &total_ns);
+
 	avg_ns.ns = total_ns.ns / ntimes;
 	avg_ns.ns_frac = total_ns.ns_frac / ntimes;
 
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* [kvm-unit-tests PATCH v3 10/10] arm64: microbench: Add timer_post() to get actual PPI latency
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (8 preceding siblings ...)
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 09/10] arm64: microbench: Add test->post() to further process test results Jingyi Wang
@ 2020-07-31  7:42 ` Jingyi Wang
  2020-07-31 12:01 ` [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Andrew Jones
                   ` (2 subsequent siblings)
  12 siblings, 0 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-07-31  7:42 UTC (permalink / raw)
  To: drjones, kvm, kvmarm
  Cc: maz, wanghaibin.wang, yuzenghui, eric.auger, wangjingyi11, prime.zeng

For we get the time duration of (10msec timer + injection latency)
in timer_exec(), we substract the value of 10msec in timer_post()
to get the actual latency.

Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
---
 arm/micro-bench.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/arm/micro-bench.c b/arm/micro-bench.c
index 4680ba4..315fc7c 100644
--- a/arm/micro-bench.c
+++ b/arm/micro-bench.c
@@ -254,6 +254,18 @@ static void timer_exec(void)
 	assert_msg(irq_received, "failed to receive PPI in time, but received %d successfully\n", received);
 }
 
+static void timer_post(uint64_t total_ticks, uint64_t ntimes, struct ns_time *total_ns)
+{
+	/*
+	 * We use a 10msec timer to test the latency of PPI,
+	 * so we substract the ticks of 10msec to get the
+	 * actual latency
+	 */
+
+	total_ticks -= ntimes * (cntfrq / 100);
+	ticks_to_ns_time(total_ticks, total_ns);
+}
+
 static void hvc_exec(void)
 {
 	asm volatile("mov w0, #0x4b000000; hvc #0" ::: "w0");
@@ -302,7 +314,7 @@ static struct exit_test tests[] = {
 	{"ipi",			ipi_prep,	ipi_exec,		NULL,		65536,		true},
 	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		NULL,		65536,		true},
 	{"lpi",			lpi_prep,	lpi_exec,		NULL,		65536,		true},
-	{"timer_10ms",		timer_prep,	timer_exec,		NULL,		256,		true},
+	{"timer_10ms",		timer_prep,	timer_exec,		timer_post,	256,		true},
 };
 
 #define PS_PER_SEC (1000 * 1000 * 1000 * 1000UL)
-- 
2.19.1



^ permalink raw reply related	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (9 preceding siblings ...)
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 10/10] arm64: microbench: Add timer_post() to get actual PPI latency Jingyi Wang
@ 2020-07-31 12:01 ` Andrew Jones
  2020-08-03  2:15   ` Jingyi Wang
  2020-08-01 17:40 ` Andrew Jones
  2020-08-05 11:54 ` Jingyi Wang
  12 siblings, 1 reply; 23+ messages in thread
From: Andrew Jones @ 2020-07-31 12:01 UTC (permalink / raw)
  To: Jingyi Wang
  Cc: kvm, kvmarm, maz, wanghaibin.wang, yuzenghui, eric.auger, prime.zeng

On Fri, Jul 31, 2020 at 03:42:34PM +0800, Jingyi Wang wrote:
> With the development of arm gic architecture, we think it will be useful
> to add some performance test in kut to measure the cost of interrupts.
> In this series, we add GICv4.1 support for ipi latency test and
> implement LPI/vtimer latency test.
> 
> This series of patches has been tested on GICv4.1 supported hardware.
> 
> Note:
> Based on patch "arm/arm64: timer: Extract irqs at setup time",
> https://www.spinics.net/lists/kvm-arm/msg41425.html
> 
> * From v2:
>   - Code and commit message cleanup
>   - Clear nr_ipi_received before ipi_exec() thanks for Tao Zeng's review
>   - rebase the patch "Add vtimer latency test" on Andrew's patch

It'd be good if you'd reposted my patch along with this series, since we
didn't merge mine yet either. Don't worry about now, though, I'll pick it
up the same time I pick up this series, which I plan to do later today
or tomorrow.

Getting this series applied will allow me to try out our new and shiny
gitlab repo :-)

Thanks,
drew

>   - Add test->post() to get actual PPI latency
> 
> * From v1:
>   - Fix spelling mistake
>   - Use the existing interface to inject hw sgi to simply the logic
>   - Add two separate patches to limit the running times and time cost
>     of each individual micro-bench test
> 
> Jingyi Wang (10):
>   arm64: microbench: get correct ipi received num
>   arm64: microbench: Generalize ipi test names
>   arm64: microbench: gic: Add ipi latency test for gicv4.1 support kvm
>   arm64: its: Handle its command queue wrapping
>   arm64: microbench: its: Add LPI latency test
>   arm64: microbench: Allow each test to specify its running times
>   arm64: microbench: Add time limit for each individual test
>   arm64: microbench: Add vtimer latency test
>   arm64: microbench: Add test->post() to further process test results
>   arm64: microbench: Add timer_post() to get actual PPI latency
> 
>  arm/micro-bench.c          | 256 ++++++++++++++++++++++++++++++-------
>  lib/arm/asm/gic-v3.h       |   3 +
>  lib/arm/asm/gic.h          |   1 +
>  lib/arm64/gic-v3-its-cmd.c |   3 +-
>  4 files changed, 219 insertions(+), 44 deletions(-)
> 
> -- 
> 2.19.1
> 
> 


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 07/10] arm64: microbench: Add time limit for each individual test
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 07/10] arm64: microbench: Add time limit for each individual test Jingyi Wang
@ 2020-08-01 16:13   ` Andrew Jones
  0 siblings, 0 replies; 23+ messages in thread
From: Andrew Jones @ 2020-08-01 16:13 UTC (permalink / raw)
  To: Jingyi Wang
  Cc: kvm, kvmarm, maz, wanghaibin.wang, yuzenghui, eric.auger, prime.zeng

On Fri, Jul 31, 2020 at 03:42:41PM +0800, Jingyi Wang wrote:
> Besides using separate running times parameter, we add time limit
> for loop_test to make sure each test should be done in a certain
> time(5 sec here).
> 
> Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
> Reviewed-by: Eric Auger <eric.auger@redhat.com>
> ---
>  arm/micro-bench.c | 18 +++++++++++-------
>  1 file changed, 11 insertions(+), 7 deletions(-)
> 
> diff --git a/arm/micro-bench.c b/arm/micro-bench.c
> index 93bd855..09d9d53 100644
> --- a/arm/micro-bench.c
> +++ b/arm/micro-bench.c
> @@ -22,6 +22,7 @@
>  #include <asm/gic.h>
>  #include <asm/gic-v3-its.h>
>  
> +#define NS_5_SECONDS (5 * 1000 * 1000 * 1000UL)
>  static u32 cntfrq;
>  
>  static volatile bool irq_ready, irq_received;
> @@ -267,23 +268,26 @@ static void loop_test(struct exit_test *test)
>  	uint64_t start, end, total_ticks, ntimes = 0;
>  	struct ns_time total_ns, avg_ns;
>  
> +	total_ticks = 0;
>  	if (test->prep) {
>  		if(!test->prep()) {
>  			printf("%s test skipped\n", test->name);
>  			return;
>  		}
>  	}
> -	isb();
> -	start = read_sysreg(cntpct_el0);
> -	while (ntimes < test->times) {
> +
> +	while (ntimes < test->times && total_ns.ns < NS_5_SECONDS) {

total_ns.ns is now being used uninitialized here. It needs to be
initialized to zero above with total_ns = {}.

I'll do this fixup myself.

Thanks,
drew

> +		isb();
> +		start = read_sysreg(cntpct_el0);
>  		test->exec();
> +		isb();
> +		end = read_sysreg(cntpct_el0);
> +
>  		ntimes++;
> +		total_ticks += (end - start);
> +		ticks_to_ns_time(total_ticks, &total_ns);
>  	}
> -	isb();
> -	end = read_sysreg(cntpct_el0);
>  
> -	total_ticks = end - start;
> -	ticks_to_ns_time(total_ticks, &total_ns);
>  	avg_ns.ns = total_ns.ns / ntimes;
>  	avg_ns.ns_frac = total_ns.ns_frac / ntimes;
>  
> -- 
> 2.19.1
> 
> 


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 08/10] arm64: microbench: Add vtimer latency test
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 08/10] arm64: microbench: Add vtimer latency test Jingyi Wang
@ 2020-08-01 16:22   ` Andrew Jones
  0 siblings, 0 replies; 23+ messages in thread
From: Andrew Jones @ 2020-08-01 16:22 UTC (permalink / raw)
  To: Jingyi Wang
  Cc: kvm, kvmarm, maz, wanghaibin.wang, yuzenghui, eric.auger, prime.zeng

On Fri, Jul 31, 2020 at 03:42:42PM +0800, Jingyi Wang wrote:
> Trigger PPIs by setting up a 10msec timer and test the latency.
> 
> Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
> ---
>  arm/micro-bench.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 52 insertions(+), 1 deletion(-)
> 
> diff --git a/arm/micro-bench.c b/arm/micro-bench.c
> index 09d9d53..1e1bde5 100644
> --- a/arm/micro-bench.c
> +++ b/arm/micro-bench.c
> @@ -21,8 +21,10 @@
>  #include <libcflat.h>
>  #include <asm/gic.h>
>  #include <asm/gic-v3-its.h>
> +#include <asm/timer.h>
>  
>  #define NS_5_SECONDS (5 * 1000 * 1000 * 1000UL)
> +
>  static u32 cntfrq;
>  
>  static volatile bool irq_ready, irq_received;
> @@ -33,9 +35,16 @@ static void (*write_eoir)(u32 irqstat);
>  
>  static void gic_irq_handler(struct pt_regs *regs)
>  {
> +	u32 irqstat = gic_read_iar();
>  	irq_ready = false;
>  	irq_received = true;
> -	gic_write_eoir(gic_read_iar());
> +	gic_write_eoir(irqstat);
> +
> +	if (irqstat == PPI(TIMER_VTIMER_IRQ)) {
> +		write_sysreg((ARCH_TIMER_CTL_IMASK | ARCH_TIMER_CTL_ENABLE),
> +			     cntv_ctl_el0);
> +		isb();
> +	}
>  	irq_ready = true;
>  }
>  
> @@ -198,6 +207,47 @@ static void lpi_exec(void)
>  	assert_msg(irq_received, "failed to receive LPI in time, but received %d successfully\n", received);
>  }
>  
> +static bool timer_prep(void)
> +{
> +	static void *gic_isenabler;

This doesn't need to be static.

> +
> +	gic_enable_defaults();
> +	install_irq_handler(EL1H_IRQ, gic_irq_handler);
> +	local_irq_enable();
> +
> +	gic_isenabler = gicv3_sgi_base() + GICR_ISENABLER0;

We can't assume GICv3. This test also runs with GICv2.

I'll fix this up myself.

Thanks,
drew

> +	writel(1 << PPI(TIMER_VTIMER_IRQ), gic_isenabler);
> +	write_sysreg(ARCH_TIMER_CTL_ENABLE, cntv_ctl_el0);
> +	isb();
> +
> +	gic_prep_common();
> +	return true;
> +}
> +
> +static void timer_exec(void)
> +{
> +	u64 before_timer;
> +	u64 timer_10ms;
> +	unsigned tries = 1 << 28;
> +	static int received = 0;
> +
> +	irq_received = false;
> +
> +	before_timer = read_sysreg(cntvct_el0);
> +	timer_10ms = cntfrq / 100;
> +	write_sysreg(before_timer + timer_10ms, cntv_cval_el0);
> +	write_sysreg(ARCH_TIMER_CTL_ENABLE, cntv_ctl_el0);
> +	isb();
> +
> +	while (!irq_received && tries--)
> +		cpu_relax();
> +
> +	if (irq_received)
> +		++received;
> +
> +	assert_msg(irq_received, "failed to receive PPI in time, but received %d successfully\n", received);
> +}
> +
>  static void hvc_exec(void)
>  {
>  	asm volatile("mov w0, #0x4b000000; hvc #0" ::: "w0");
> @@ -245,6 +295,7 @@ static struct exit_test tests[] = {
>  	{"ipi",			ipi_prep,	ipi_exec,		65536,		true},
>  	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		65536,		true},
>  	{"lpi",			lpi_prep,	lpi_exec,		65536,		true},
> +	{"timer_10ms",		timer_prep,	timer_exec,		256,		true},
>  };
>  
>  struct ns_time {
> -- 
> 2.19.1
> 
> 


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 09/10] arm64: microbench: Add test->post() to further process test results
  2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 09/10] arm64: microbench: Add test->post() to further process test results Jingyi Wang
@ 2020-08-01 17:03   ` Andrew Jones
  0 siblings, 0 replies; 23+ messages in thread
From: Andrew Jones @ 2020-08-01 17:03 UTC (permalink / raw)
  To: Jingyi Wang
  Cc: kvm, kvmarm, maz, wanghaibin.wang, yuzenghui, eric.auger, prime.zeng

On Fri, Jul 31, 2020 at 03:42:43PM +0800, Jingyi Wang wrote:
> Under certain circumstances, we need to further process microbench
> test results, so we add test->post() in the microbench framework,
> later patch will use that.
> 
> Signed-off-by: Jingyi Wang <wangjingyi11@huawei.com>
> ---
>  arm/micro-bench.c | 31 ++++++++++++++++++-------------
>  1 file changed, 18 insertions(+), 13 deletions(-)
> 
> diff --git a/arm/micro-bench.c b/arm/micro-bench.c
> index 1e1bde5..4680ba4 100644
> --- a/arm/micro-bench.c
> +++ b/arm/micro-bench.c
> @@ -33,6 +33,12 @@ static int nr_ipi_received;
>  static void *vgic_dist_base;
>  static void (*write_eoir)(u32 irqstat);
>  
> +struct ns_time {
> +	uint64_t ns;
> +	uint64_t ns_frac;
> +};

Missing blank line

> +static void ticks_to_ns_time(uint64_t ticks, struct ns_time *ns_time);

You could have moved the whole function up here.

> +
>  static void gic_irq_handler(struct pt_regs *regs)
>  {
>  	u32 irqstat = gic_read_iar();
> @@ -283,24 +289,20 @@ struct exit_test {
>  	const char *name;
>  	bool (*prep)(void);
>  	void (*exec)(void);
> +	void (*post)(uint64_t, uint64_t, struct ns_time*);
>  	u32 times;
>  	bool run;
>  };
>  
>  static struct exit_test tests[] = {
> -	{"hvc",			NULL,		hvc_exec,		65536,		true},
> -	{"mmio_read_user",	NULL,		mmio_read_user_exec,	65536,		true},
> -	{"mmio_read_vgic",	NULL,		mmio_read_vgic_exec,	65536,		true},
> -	{"eoi",			NULL,		eoi_exec,		65536,		true},
> -	{"ipi",			ipi_prep,	ipi_exec,		65536,		true},
> -	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		65536,		true},
> -	{"lpi",			lpi_prep,	lpi_exec,		65536,		true},
> -	{"timer_10ms",		timer_prep,	timer_exec,		256,		true},
> -};
> -
> -struct ns_time {
> -	uint64_t ns;
> -	uint64_t ns_frac;
> +	{"hvc",			NULL,		hvc_exec,		NULL,		65536,		true},
> +	{"mmio_read_user",	NULL,		mmio_read_user_exec,	NULL,		65536,		true},
> +	{"mmio_read_vgic",	NULL,		mmio_read_vgic_exec,	NULL,		65536,		true},
> +	{"eoi",			NULL,		eoi_exec,		NULL,		65536,		true},
> +	{"ipi",			ipi_prep,	ipi_exec,		NULL,		65536,		true},
> +	{"ipi_hw",		ipi_hw_prep,	ipi_exec,		NULL,		65536,		true},
> +	{"lpi",			lpi_prep,	lpi_exec,		NULL,		65536,		true},
> +	{"timer_10ms",		timer_prep,	timer_exec,		NULL,		256,		true},
>  };
>  
>  #define PS_PER_SEC (1000 * 1000 * 1000 * 1000UL)
> @@ -339,6 +341,9 @@ static void loop_test(struct exit_test *test)
>  		ticks_to_ns_time(total_ticks, &total_ns);
>  	}
>  
> +	if (test->post)
> +		test->post(total_ticks, ntimes, &total_ns);
> +

We can drop the ns_time structure and pass total_ticks by reference.

>  	avg_ns.ns = total_ns.ns / ntimes;
>  	avg_ns.ns_frac = total_ns.ns_frac / ntimes;
>  
> -- 
> 2.19.1
> 
>

I can do these changes myself.

Thanks,
drew


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (10 preceding siblings ...)
  2020-07-31 12:01 ` [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Andrew Jones
@ 2020-08-01 17:40 ` Andrew Jones
  2020-08-05 11:54 ` Jingyi Wang
  12 siblings, 0 replies; 23+ messages in thread
From: Andrew Jones @ 2020-08-01 17:40 UTC (permalink / raw)
  To: Jingyi Wang
  Cc: kvm, kvmarm, maz, wanghaibin.wang, yuzenghui, eric.auger, prime.zeng

On Fri, Jul 31, 2020 at 03:42:34PM +0800, Jingyi Wang wrote:
> With the development of arm gic architecture, we think it will be useful
> to add some performance test in kut to measure the cost of interrupts.
> In this series, we add GICv4.1 support for ipi latency test and
> implement LPI/vtimer latency test.
> 
> This series of patches has been tested on GICv4.1 supported hardware.
> 
> Note:
> Based on patch "arm/arm64: timer: Extract irqs at setup time",
> https://www.spinics.net/lists/kvm-arm/msg41425.html
> 
> * From v2:
>   - Code and commit message cleanup
>   - Clear nr_ipi_received before ipi_exec() thanks for Tao Zeng's review
>   - rebase the patch "Add vtimer latency test" on Andrew's patch
>   - Add test->post() to get actual PPI latency
> 
> * From v1:
>   - Fix spelling mistake
>   - Use the existing interface to inject hw sgi to simply the logic
>   - Add two separate patches to limit the running times and time cost
>     of each individual micro-bench test
> 
> Jingyi Wang (10):
>   arm64: microbench: get correct ipi received num
>   arm64: microbench: Generalize ipi test names
>   arm64: microbench: gic: Add ipi latency test for gicv4.1 support kvm
>   arm64: its: Handle its command queue wrapping
>   arm64: microbench: its: Add LPI latency test
>   arm64: microbench: Allow each test to specify its running times
>   arm64: microbench: Add time limit for each individual test
>   arm64: microbench: Add vtimer latency test
>   arm64: microbench: Add test->post() to further process test results
>   arm64: microbench: Add timer_post() to get actual PPI latency
> 
>  arm/micro-bench.c          | 256 ++++++++++++++++++++++++++++++-------
>  lib/arm/asm/gic-v3.h       |   3 +
>  lib/arm/asm/gic.h          |   1 +
>  lib/arm64/gic-v3-its-cmd.c |   3 +-
>  4 files changed, 219 insertions(+), 44 deletions(-)
> 
> -- 
> 2.19.1
> 
>

Pushed

(to the new repo at https://gitlab.com/kvm-unit-tests/kvm-unit-tests.git)

Thanks,
drew


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-07-31 12:01 ` [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Andrew Jones
@ 2020-08-03  2:15   ` Jingyi Wang
  0 siblings, 0 replies; 23+ messages in thread
From: Jingyi Wang @ 2020-08-03  2:15 UTC (permalink / raw)
  To: Andrew Jones
  Cc: kvm, kvmarm, maz, wanghaibin.wang, yuzenghui, eric.auger, prime.zeng



On 7/31/2020 8:01 PM, Andrew Jones wrote:
> On Fri, Jul 31, 2020 at 03:42:34PM +0800, Jingyi Wang wrote:
>> With the development of arm gic architecture, we think it will be useful
>> to add some performance test in kut to measure the cost of interrupts.
>> In this series, we add GICv4.1 support for ipi latency test and
>> implement LPI/vtimer latency test.
>>
>> This series of patches has been tested on GICv4.1 supported hardware.
>>
>> Note:
>> Based on patch "arm/arm64: timer: Extract irqs at setup time",
>> https://www.spinics.net/lists/kvm-arm/msg41425.html
>>
>> * From v2:
>>    - Code and commit message cleanup
>>    - Clear nr_ipi_received before ipi_exec() thanks for Tao Zeng's review
>>    - rebase the patch "Add vtimer latency test" on Andrew's patch
> 
> It'd be good if you'd reposted my patch along with this series, since we
> didn't merge mine yet either. Don't worry about now, though, I'll pick it
> up the same time I pick up this series, which I plan to do later today
> or tomorrow.
> 
> Getting this series applied will allow me to try out our new and shiny
> gitlab repo :-)
> 
> Thanks,
> drew
> 

Thanks for your reviewing and fix.

>>    - Add test->post() to get actual PPI latency
>>
>> * From v1:
>>    - Fix spelling mistake
>>    - Use the existing interface to inject hw sgi to simply the logic
>>    - Add two separate patches to limit the running times and time cost
>>      of each individual micro-bench test
>>
>> Jingyi Wang (10):
>>    arm64: microbench: get correct ipi received num
>>    arm64: microbench: Generalize ipi test names
>>    arm64: microbench: gic: Add ipi latency test for gicv4.1 support kvm
>>    arm64: its: Handle its command queue wrapping
>>    arm64: microbench: its: Add LPI latency test
>>    arm64: microbench: Allow each test to specify its running times
>>    arm64: microbench: Add time limit for each individual test
>>    arm64: microbench: Add vtimer latency test
>>    arm64: microbench: Add test->post() to further process test results
>>    arm64: microbench: Add timer_post() to get actual PPI latency
>>
>>   arm/micro-bench.c          | 256 ++++++++++++++++++++++++++++++-------
>>   lib/arm/asm/gic-v3.h       |   3 +
>>   lib/arm/asm/gic.h          |   1 +
>>   lib/arm64/gic-v3-its-cmd.c |   3 +-
>>   4 files changed, 219 insertions(+), 44 deletions(-)
>>
>> -- 
>> 2.19.1
>>
>>
> 
> 
> .
> 


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
                   ` (11 preceding siblings ...)
  2020-08-01 17:40 ` Andrew Jones
@ 2020-08-05 11:54 ` Jingyi Wang
  2020-08-05 12:13   ` Marc Zyngier
  12 siblings, 1 reply; 23+ messages in thread
From: Jingyi Wang @ 2020-08-05 11:54 UTC (permalink / raw)
  To: drjones, kvm, kvmarm, maz, eric.auger; +Cc: wanghaibin.wang, yuzenghui

Hi all,

Currently, kvm-unit-tests only support GICv3 vLPI injection. May I ask
is there any plan or suggestion on constructing irq bypass mechanism
to test vLPI direct injection in kvm-unit-tests?

Thanks,
Jingyi


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-08-05 11:54 ` Jingyi Wang
@ 2020-08-05 12:13   ` Marc Zyngier
  2020-08-11  1:48     ` Jingyi Wang
  0 siblings, 1 reply; 23+ messages in thread
From: Marc Zyngier @ 2020-08-05 12:13 UTC (permalink / raw)
  To: Jingyi Wang; +Cc: drjones, kvm, kvmarm, eric.auger, wanghaibin.wang, yuzenghui

On 2020-08-05 12:54, Jingyi Wang wrote:
> Hi all,
> 
> Currently, kvm-unit-tests only support GICv3 vLPI injection. May I ask
> is there any plan or suggestion on constructing irq bypass mechanism
> to test vLPI direct injection in kvm-unit-tests?

I'm not sure what you are asking for here. VLPIs are only delivered
from a HW device, and the offloading mechanism isn't visible from
userspace (you either have an enabled GICv4 implementation, or
you don't).

There are ways to *trigger* device MSIs from userspace and inject
them in a guest, but that's only a debug feature, which shouldn't
be enabled on a production system.

         M.
-- 
Jazz is not dead. It just smells funny...

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-08-05 12:13   ` Marc Zyngier
@ 2020-08-11  1:48     ` Jingyi Wang
  2020-08-11  7:49       ` Marc Zyngier
  0 siblings, 1 reply; 23+ messages in thread
From: Jingyi Wang @ 2020-08-11  1:48 UTC (permalink / raw)
  To: Marc Zyngier; +Cc: drjones, kvm, kvmarm, eric.auger, wanghaibin.wang, yuzenghui

Hi Marc,

On 8/5/2020 8:13 PM, Marc Zyngier wrote:
> On 2020-08-05 12:54, Jingyi Wang wrote:
>> Hi all,
>>
>> Currently, kvm-unit-tests only support GICv3 vLPI injection. May I ask
>> is there any plan or suggestion on constructing irq bypass mechanism
>> to test vLPI direct injection in kvm-unit-tests?
> 
> I'm not sure what you are asking for here. VLPIs are only delivered
> from a HW device, and the offloading mechanism isn't visible from
> userspace (you either have an enabled GICv4 implementation, or
> you don't).
> 
> There are ways to *trigger* device MSIs from userspace and inject
> them in a guest, but that's only a debug feature, which shouldn't
> be enabled on a production system.
> 
>          M.

Sorry for the late reply.

As I mentioned before, we want to add vLPI direct injection test
in KUT, meanwhile measure the latency of hardware vLPI injection.

Sure, vLPI is triggered by hardware. Since kernel supports sending
ITS INT command in guest to trigger vLPI, I wonder if it is possible
to add an extra interface to make a vLPI hardware-offload(just as
kvm_vgic_v4_set_forwarding() does). If so, vgic_its_trigger_msi()
can inject vLPI directly instead of using LR.

Thanks,
Jingyi


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-08-11  1:48     ` Jingyi Wang
@ 2020-08-11  7:49       ` Marc Zyngier
  2020-08-17  1:46         ` Jingyi Wang
  0 siblings, 1 reply; 23+ messages in thread
From: Marc Zyngier @ 2020-08-11  7:49 UTC (permalink / raw)
  To: Jingyi Wang; +Cc: drjones, kvm, kvmarm, eric.auger, wanghaibin.wang, yuzenghui

On 2020-08-11 02:48, Jingyi Wang wrote:
> Hi Marc,
> 
> On 8/5/2020 8:13 PM, Marc Zyngier wrote:
>> On 2020-08-05 12:54, Jingyi Wang wrote:
>>> Hi all,
>>> 
>>> Currently, kvm-unit-tests only support GICv3 vLPI injection. May I 
>>> ask
>>> is there any plan or suggestion on constructing irq bypass mechanism
>>> to test vLPI direct injection in kvm-unit-tests?
>> 
>> I'm not sure what you are asking for here. VLPIs are only delivered
>> from a HW device, and the offloading mechanism isn't visible from
>> userspace (you either have an enabled GICv4 implementation, or
>> you don't).
>> 
>> There are ways to *trigger* device MSIs from userspace and inject
>> them in a guest, but that's only a debug feature, which shouldn't
>> be enabled on a production system.
>> 
>>          M.
> 
> Sorry for the late reply.
> 
> As I mentioned before, we want to add vLPI direct injection test
> in KUT, meanwhile measure the latency of hardware vLPI injection.
> 
> Sure, vLPI is triggered by hardware. Since kernel supports sending
> ITS INT command in guest to trigger vLPI, I wonder if it is possible

So can the host.

> to add an extra interface to make a vLPI hardware-offload(just as
> kvm_vgic_v4_set_forwarding() does). If so, vgic_its_trigger_msi()
> can inject vLPI directly instead of using LR.

The interface exists, it is in debugfs. But it mandates that the
device exists. And no, I am not willing to add an extra KVM userspace
API for this.

The whole concept of injecting an INT to measure the performance
of GICv4 is slightly bonkers, actually. Most of the cost is paid
on the injection path (queuing a pair of command, waiting until
the ITS wakes up and generate the signal...).

What you really want to measure is the time from generation of
the LPI by a device until the guest acknowledges the interrupt
to the device itself. and this can only be implemented in the
device.

         M.
-- 
Jazz is not dead. It just smells funny...

^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-08-11  7:49       ` Marc Zyngier
@ 2020-08-17  1:46         ` Jingyi Wang
  2020-08-17  8:26           ` Marc Zyngier
  0 siblings, 1 reply; 23+ messages in thread
From: Jingyi Wang @ 2020-08-17  1:46 UTC (permalink / raw)
  To: Marc Zyngier; +Cc: drjones, kvm, kvmarm, eric.auger, wanghaibin.wang, yuzenghui

On 8/11/2020 3:49 PM, Marc Zyngier wrote:
> On 2020-08-11 02:48, Jingyi Wang wrote:
>> Hi Marc,
>>
>> On 8/5/2020 8:13 PM, Marc Zyngier wrote:
>>> On 2020-08-05 12:54, Jingyi Wang wrote:
>>>> Hi all,
>>>>
>>>> Currently, kvm-unit-tests only support GICv3 vLPI injection. May I ask
>>>> is there any plan or suggestion on constructing irq bypass mechanism
>>>> to test vLPI direct injection in kvm-unit-tests?
>>>
>>> I'm not sure what you are asking for here. VLPIs are only delivered
>>> from a HW device, and the offloading mechanism isn't visible from
>>> userspace (you either have an enabled GICv4 implementation, or
>>> you don't).
>>>
>>> There are ways to *trigger* device MSIs from userspace and inject
>>> them in a guest, but that's only a debug feature, which shouldn't
>>> be enabled on a production system.
>>>
>>>          M.
>>
>> Sorry for the late reply.
>>
>> As I mentioned before, we want to add vLPI direct injection test
>> in KUT, meanwhile measure the latency of hardware vLPI injection.
>>
>> Sure, vLPI is triggered by hardware. Since kernel supports sending
>> ITS INT command in guest to trigger vLPI, I wonder if it is possible
> 
> So can the host.
> 
>> to add an extra interface to make a vLPI hardware-offload(just as
>> kvm_vgic_v4_set_forwarding() does). If so, vgic_its_trigger_msi()
>> can inject vLPI directly instead of using LR.
> 
> The interface exists, it is in debugfs. But it mandates that the
> device exists. And no, I am not willing to add an extra KVM userspace
> API for this.
> 
> The whole concept of injecting an INT to measure the performance
> of GICv4 is slightly bonkers, actually. Most of the cost is paid
> on the injection path (queuing a pair of command, waiting until
> the ITS wakes up and generate the signal...).
> 
> What you really want to measure is the time from generation of
> the LPI by a device until the guest acknowledges the interrupt
> to the device itself. and this can only be implemented in the
> device.
> 
>          M.

OK understood. I just thought measuring the latency of the path
kvm->guest can be useful.

Thanks,
Jingyi


^ permalink raw reply	[flat|nested] 23+ messages in thread

* Re: [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test
  2020-08-17  1:46         ` Jingyi Wang
@ 2020-08-17  8:26           ` Marc Zyngier
  0 siblings, 0 replies; 23+ messages in thread
From: Marc Zyngier @ 2020-08-17  8:26 UTC (permalink / raw)
  To: Jingyi Wang; +Cc: drjones, kvm, kvmarm, eric.auger, wanghaibin.wang, yuzenghui

On 2020-08-17 02:46, Jingyi Wang wrote:
> On 8/11/2020 3:49 PM, Marc Zyngier wrote:
>> On 2020-08-11 02:48, Jingyi Wang wrote:

[...]

>>> As I mentioned before, we want to add vLPI direct injection test
>>> in KUT, meanwhile measure the latency of hardware vLPI injection.
>>> 
>>> Sure, vLPI is triggered by hardware. Since kernel supports sending
>>> ITS INT command in guest to trigger vLPI, I wonder if it is possible
>> 
>> So can the host.
>> 
>>> to add an extra interface to make a vLPI hardware-offload(just as
>>> kvm_vgic_v4_set_forwarding() does). If so, vgic_its_trigger_msi()
>>> can inject vLPI directly instead of using LR.
>> 
>> The interface exists, it is in debugfs. But it mandates that the
>> device exists. And no, I am not willing to add an extra KVM userspace
>> API for this.
>> 
>> The whole concept of injecting an INT to measure the performance
>> of GICv4 is slightly bonkers, actually. Most of the cost is paid
>> on the injection path (queuing a pair of command, waiting until
>> the ITS wakes up and generate the signal...).
>> 
>> What you really want to measure is the time from generation of
>> the LPI by a device until the guest acknowledges the interrupt
>> to the device itself. and this can only be implemented in the
>> device.
>> 
>>          M.
> 
> OK understood. I just thought measuring the latency of the path
> kvm->guest can be useful.

That's the problem. There is no way you can implement this, because
you cannot distinguish injection latency from the delivery latency.
And frankly, it doesn't matter, because the hypervisor is not on
that path at all (if it is slow, that's because the HW is slow, and
you can't change anything in KVM to make it better).

On the other hand, measuring the latency of a guest being scheduled
back in when blocked on WFI would be much more relevant, as this is
exactly what would happen on delivery of a doorbell.

         M.
-- 
Jazz is not dead. It just smells funny...

^ permalink raw reply	[flat|nested] 23+ messages in thread

end of thread, other threads:[~2020-08-17  8:27 UTC | newest]

Thread overview: 23+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-31  7:42 [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Jingyi Wang
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 01/10] arm64: microbench: get correct ipi received num Jingyi Wang
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 02/10] arm64: microbench: Generalize ipi test names Jingyi Wang
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 03/10] arm64: microbench: gic: Add ipi latency test for gicv4.1 support kvm Jingyi Wang
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 04/10] arm64: its: Handle its command queue wrapping Jingyi Wang
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 05/10] arm64: microbench: its: Add LPI latency test Jingyi Wang
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 06/10] arm64: microbench: Allow each test to specify its running times Jingyi Wang
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 07/10] arm64: microbench: Add time limit for each individual test Jingyi Wang
2020-08-01 16:13   ` Andrew Jones
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 08/10] arm64: microbench: Add vtimer latency test Jingyi Wang
2020-08-01 16:22   ` Andrew Jones
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 09/10] arm64: microbench: Add test->post() to further process test results Jingyi Wang
2020-08-01 17:03   ` Andrew Jones
2020-07-31  7:42 ` [kvm-unit-tests PATCH v3 10/10] arm64: microbench: Add timer_post() to get actual PPI latency Jingyi Wang
2020-07-31 12:01 ` [kvm-unit-tests PATCH v3 00/10] arm/arm64: Add IPI/LPI/vtimer latency test Andrew Jones
2020-08-03  2:15   ` Jingyi Wang
2020-08-01 17:40 ` Andrew Jones
2020-08-05 11:54 ` Jingyi Wang
2020-08-05 12:13   ` Marc Zyngier
2020-08-11  1:48     ` Jingyi Wang
2020-08-11  7:49       ` Marc Zyngier
2020-08-17  1:46         ` Jingyi Wang
2020-08-17  8:26           ` Marc Zyngier

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).