From: Peter Zijlstra <peterz@infradead.org>
To: x86@kernel.org
Cc: peterz@infradead.org, linux-kernel@vger.kernel.org,
rostedt@goodmis.org, mhiramat@kernel.org, bristot@redhat.com,
jbaron@akamai.com, torvalds@linux-foundation.org,
tglx@linutronix.de, mingo@kernel.org, namit@vmware.com,
hpa@zytor.com, luto@kernel.org, ard.biesheuvel@linaro.org,
jpoimboe@redhat.com
Subject: [RFC][PATCH v2 13/13] x86/perf, static_call: Optimize x86_pmu methods
Date: Mon, 07 Oct 2019 10:27:21 +0200 [thread overview]
Message-ID: <20191007083831.26880701.6@infradead.org> (raw)
In-Reply-To: 20191007082708.01393931.1@infradead.org
Replace many of the indirect calls with static_call().
XXX run performance numbers
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/events/core.c | 136 +++++++++++++++++++++++++++++++++++--------------
1 file changed, 98 insertions(+), 38 deletions(-)
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -28,6 +28,7 @@
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/nospec.h>
+#include <linux/static_call.h>
#include <asm/apic.h>
#include <asm/stacktrace.h>
@@ -51,6 +52,45 @@ DEFINE_PER_CPU(struct cpu_hw_events, cpu
DEFINE_STATIC_KEY_FALSE(rdpmc_always_available_key);
+static void _x86_pmu_add(struct perf_event *event) { }
+static void _x86_pmu_del(struct perf_event *event) { }
+static void _x86_pmu_read(struct perf_event *event) { x86_perf_event_update(event); }
+static void _x86_pmu_put_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event) { }
+static void _x86_pmu_drain_pebs(struct pt_regs *regs) { }
+static void _x86_pmu_pebs_aliases(struct perf_event *event) { }
+static void _x86_pmu_start_scheduling(struct cpu_hw_events *cpuc) { }
+static void _x86_pmu_commit_scheduling(struct cpu_hw_events *cpuc, int idx, int cntr) { }
+static void _x86_pmu_stop_scheduling(struct cpu_hw_events *cpuc) { }
+static void _x86_pmu_sched_task(struct perf_event_context *ctx, bool sched_in) { }
+
+DEFINE_STATIC_CALL(x86_pmu_handle_irq, x86_pmu_handle_irq);
+DEFINE_STATIC_CALL(x86_pmu_disable_all, x86_pmu_disable_all);
+DEFINE_STATIC_CALL(x86_pmu_enable_all, x86_pmu_enable_all);
+DEFINE_STATIC_CALL(x86_pmu_enable, x86_pmu_enable_event);
+DEFINE_STATIC_CALL(x86_pmu_disable, x86_pmu_disable_event);
+
+DEFINE_STATIC_CALL(x86_pmu_add, _x86_pmu_add);
+DEFINE_STATIC_CALL(x86_pmu_del, _x86_pmu_del);
+DEFINE_STATIC_CALL(x86_pmu_read, _x86_pmu_read);
+
+DEFINE_STATIC_CALL(x86_pmu_schedule_events, x86_schedule_events);
+
+// addr_offset
+// rdpmc_index
+// event_map
+
+DEFINE_STATIC_CALL(x86_pmu_get_event_constraints, x86_get_event_constraints);
+DEFINE_STATIC_CALL(x86_pmu_put_event_constraints, _x86_pmu_put_event_constraints);
+
+DEFINE_STATIC_CALL(x86_pmu_drain_pebs, _x86_pmu_drain_pebs);
+DEFINE_STATIC_CALL(x86_pmu_pebs_aliases, _x86_pmu_pebs_aliases);
+
+DEFINE_STATIC_CALL(x86_pmu_start_scheduling, _x86_pmu_start_scheduling);
+DEFINE_STATIC_CALL(x86_pmu_commit_scheduling, _x86_pmu_commit_scheduling);
+DEFINE_STATIC_CALL(x86_pmu_stop_scheduling, _x86_pmu_stop_scheduling);
+
+DEFINE_STATIC_CALL(x86_pmu_sched_task, _x86_pmu_sched_task);
+
u64 __read_mostly hw_cache_event_ids
[PERF_COUNT_HW_CACHE_MAX]
[PERF_COUNT_HW_CACHE_OP_MAX]
@@ -651,7 +691,7 @@ static void x86_pmu_disable(struct pmu *
cpuc->enabled = 0;
barrier();
- x86_pmu.disable_all();
+ static_call(x86_pmu_disable_all)();
}
void x86_pmu_enable_all(int added)
@@ -884,8 +924,7 @@ int x86_schedule_events(struct cpu_hw_ev
if (cpuc->txn_flags & PERF_PMU_TXN_ADD)
n0 -= cpuc->n_txn;
- if (x86_pmu.start_scheduling)
- x86_pmu.start_scheduling(cpuc);
+ static_cond_call(x86_pmu_start_scheduling)(cpuc);
for (i = 0, wmin = X86_PMC_IDX_MAX, wmax = 0; i < n; i++) {
c = cpuc->event_constraint[i];
@@ -902,7 +941,7 @@ int x86_schedule_events(struct cpu_hw_ev
* change due to external factors (sibling state, allow_tfa).
*/
if (!c || (c->flags & PERF_X86_EVENT_DYNAMIC)) {
- c = x86_pmu.get_event_constraints(cpuc, i, cpuc->event_list[i]);
+ c = static_call(x86_pmu_get_event_constraints)(cpuc, i, cpuc->event_list[i]);
cpuc->event_constraint[i] = c;
}
@@ -969,8 +1008,7 @@ int x86_schedule_events(struct cpu_hw_ev
if (!unsched && assign) {
for (i = 0; i < n; i++) {
e = cpuc->event_list[i];
- if (x86_pmu.commit_scheduling)
- x86_pmu.commit_scheduling(cpuc, i, assign[i]);
+ static_cond_call(x86_pmu_commit_scheduling)(cpuc, i, assign[i]);
}
} else {
for (i = n0; i < n; i++) {
@@ -979,15 +1017,13 @@ int x86_schedule_events(struct cpu_hw_ev
/*
* release events that failed scheduling
*/
- if (x86_pmu.put_event_constraints)
- x86_pmu.put_event_constraints(cpuc, e);
+ static_cond_call(x86_pmu_put_event_constraints)(cpuc, e);
cpuc->event_constraint[i] = NULL;
}
}
- if (x86_pmu.stop_scheduling)
- x86_pmu.stop_scheduling(cpuc);
+ static_cond_call(x86_pmu_stop_scheduling)(cpuc);
return unsched ? -EINVAL : 0;
}
@@ -1174,7 +1210,7 @@ static void x86_pmu_enable(struct pmu *p
cpuc->enabled = 1;
barrier();
- x86_pmu.enable_all(added);
+ static_call(x86_pmu_enable_all)(added);
}
static DEFINE_PER_CPU(u64 [X86_PMC_IDX_MAX], pmc_prev_left);
@@ -1288,7 +1324,7 @@ static int x86_pmu_add(struct perf_event
if (cpuc->txn_flags & PERF_PMU_TXN_ADD)
goto done_collect;
- ret = x86_pmu.schedule_events(cpuc, n, assign);
+ ret = static_call(x86_pmu_schedule_events)(cpuc, n, assign);
if (ret)
goto out;
/*
@@ -1306,13 +1342,11 @@ static int x86_pmu_add(struct perf_event
cpuc->n_added += n - n0;
cpuc->n_txn += n - n0;
- if (x86_pmu.add) {
- /*
- * This is before x86_pmu_enable() will call x86_pmu_start(),
- * so we enable LBRs before an event needs them etc..
- */
- x86_pmu.add(event);
- }
+ /*
+ * This is before x86_pmu_enable() will call x86_pmu_start(),
+ * so we enable LBRs before an event needs them etc..
+ */
+ static_cond_call(x86_pmu_add)(event);
ret = 0;
out:
@@ -1340,7 +1374,7 @@ static void x86_pmu_start(struct perf_ev
cpuc->events[idx] = event;
__set_bit(idx, cpuc->active_mask);
__set_bit(idx, cpuc->running);
- x86_pmu.enable(event);
+ static_call(x86_pmu_enable)(event);
perf_event_update_userpage(event);
}
@@ -1410,7 +1444,7 @@ void x86_pmu_stop(struct perf_event *eve
struct hw_perf_event *hwc = &event->hw;
if (test_bit(hwc->idx, cpuc->active_mask)) {
- x86_pmu.disable(event);
+ static_call(x86_pmu_disable)(event);
__clear_bit(hwc->idx, cpuc->active_mask);
cpuc->events[hwc->idx] = NULL;
WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
@@ -1460,8 +1494,7 @@ static void x86_pmu_del(struct perf_even
if (i >= cpuc->n_events - cpuc->n_added)
--cpuc->n_added;
- if (x86_pmu.put_event_constraints)
- x86_pmu.put_event_constraints(cpuc, event);
+ static_cond_call(x86_pmu_put_event_constraints)(cpuc, event);
/* Delete the array entry. */
while (++i < cpuc->n_events) {
@@ -1474,13 +1507,12 @@ static void x86_pmu_del(struct perf_even
perf_event_update_userpage(event);
do_del:
- if (x86_pmu.del) {
- /*
- * This is after x86_pmu_stop(); so we disable LBRs after any
- * event can need them etc..
- */
- x86_pmu.del(event);
- }
+
+ /*
+ * This is after x86_pmu_stop(); so we disable LBRs after any
+ * event can need them etc..
+ */
+ static_cond_call(x86_pmu_del)(event);
}
int x86_pmu_handle_irq(struct pt_regs *regs)
@@ -1558,7 +1590,7 @@ perf_event_nmi_handler(unsigned int cmd,
return NMI_DONE;
start_clock = sched_clock();
- ret = x86_pmu.handle_irq(regs);
+ ret = static_call(x86_pmu_handle_irq)(regs);
finish_clock = sched_clock();
perf_sample_event_took(finish_clock - start_clock);
@@ -1765,6 +1797,32 @@ ssize_t x86_event_sysfs_show(char *page,
static struct attribute_group x86_pmu_attr_group;
static struct attribute_group x86_pmu_caps_group;
+static void x86_pmu_static_call_update(void)
+{
+ static_call_update(x86_pmu_handle_irq, x86_pmu.handle_irq);
+ static_call_update(x86_pmu_disable_all, x86_pmu.disable_all);
+ static_call_update(x86_pmu_enable_all, x86_pmu.enable_all);
+ static_call_update(x86_pmu_enable, x86_pmu.enable);
+ static_call_update(x86_pmu_disable, x86_pmu.disable);
+
+ static_call_update(x86_pmu_add, x86_pmu.add);
+ static_call_update(x86_pmu_del, x86_pmu.del);
+ static_call_update(x86_pmu_read, x86_pmu.read);
+
+ static_call_update(x86_pmu_schedule_events, x86_pmu.schedule_events);
+ static_call_update(x86_pmu_get_event_constraints, x86_pmu.get_event_constraints);
+ static_call_update(x86_pmu_put_event_constraints, x86_pmu.put_event_constraints);
+
+ static_call_update(x86_pmu_drain_pebs, x86_pmu.drain_pebs);
+ static_call_update(x86_pmu_pebs_aliases, x86_pmu.pebs_aliases);
+
+ static_call_update(x86_pmu_start_scheduling, x86_pmu.start_scheduling);
+ static_call_update(x86_pmu_commit_scheduling, x86_pmu.commit_scheduling);
+ static_call_update(x86_pmu_stop_scheduling, x86_pmu.stop_scheduling);
+
+ static_call_update(x86_pmu_sched_task, x86_pmu.sched_task);
+}
+
static int __init init_hw_perf_events(void)
{
struct x86_pmu_quirk *quirk;
@@ -1829,6 +1887,11 @@ static int __init init_hw_perf_events(vo
pr_info("... fixed-purpose events: %d\n", x86_pmu.num_counters_fixed);
pr_info("... event mask: %016Lx\n", x86_pmu.intel_ctrl);
+ if (!x86_pmu.read)
+ x86_pmu.read = _x86_pmu_read;
+
+ x86_pmu_static_call_update();
+
/*
* Install callbacks. Core will call them for each online
* cpu.
@@ -1865,11 +1928,9 @@ static int __init init_hw_perf_events(vo
}
early_initcall(init_hw_perf_events);
-static inline void x86_pmu_read(struct perf_event *event)
+static void x86_pmu_read(struct perf_event *event)
{
- if (x86_pmu.read)
- return x86_pmu.read(event);
- x86_perf_event_update(event);
+ static_call(x86_pmu_read)(event);
}
/*
@@ -1946,7 +2007,7 @@ static int x86_pmu_commit_txn(struct pmu
if (!x86_pmu_initialized())
return -EAGAIN;
- ret = x86_pmu.schedule_events(cpuc, n, assign);
+ ret = static_call(x86_pmu_schedule_events)(cpuc, n, assign);
if (ret)
return ret;
@@ -2239,8 +2300,7 @@ static const struct attribute_group *x86
static void x86_pmu_sched_task(struct perf_event_context *ctx, bool sched_in)
{
- if (x86_pmu.sched_task)
- x86_pmu.sched_task(ctx, sched_in);
+ static_cond_call(x86_pmu_sched_task)(ctx, sched_in);
}
void perf_check_microcode(void)
next prev parent reply other threads:[~2019-10-07 11:25 UTC|newest]
Thread overview: 128+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-07 9:02 [RESEND] everything text-poke: ftrace, modules, static_call and jump_label Peter Zijlstra
2019-10-07 8:17 ` [PATCH v3 0/6] Rewrite x86/ftrace to use text_poke() Peter Zijlstra
2019-10-07 8:17 ` [PATCH v3 1/6] x86/alternatives: Teach text_poke_bp() to emulate instructions Peter Zijlstra
2019-10-08 14:29 ` Borislav Petkov
2019-10-08 14:40 ` Steven Rostedt
2019-10-08 14:50 ` Borislav Petkov
2019-10-08 14:48 ` Peter Zijlstra
2019-10-08 14:54 ` Borislav Petkov
2019-10-08 15:04 ` Steven Rostedt
2019-10-08 15:24 ` Borislav Petkov
2019-10-09 12:03 ` Daniel Bristot de Oliveira
2019-10-07 8:17 ` [PATCH v3 2/6] x86/alternatives: Update int3_emulate_push() comment Peter Zijlstra
2019-10-07 8:17 ` [PATCH v3 3/6] x86/alternatives,jump_label: Provide better text_poke() batching interface Peter Zijlstra
2019-10-09 12:04 ` Daniel Bristot de Oliveira
2019-10-07 8:17 ` [PATCH v3 4/6] x86/alternatives: Add and use text_gen_insn() helper Peter Zijlstra
2019-10-08 6:23 ` Masami Hiramatsu
2019-10-08 8:15 ` Peter Zijlstra
2019-10-07 8:17 ` [PATCH v3 5/6] x86/ftrace: Use text_poke() Peter Zijlstra
2019-10-08 14:43 ` Steven Rostedt
2019-10-08 17:11 ` Peter Zijlstra
2019-10-08 17:27 ` Steven Rostedt
2019-10-10 2:41 ` Steven Rostedt
2019-10-10 9:20 ` Peter Zijlstra
2019-10-10 13:19 ` Steven Rostedt
2019-10-10 14:05 ` Peter Zijlstra
2019-10-10 15:54 ` Steven Rostedt
2019-10-10 17:28 ` Peter Zijlstra
2019-10-10 17:48 ` Steven Rostedt
2019-10-11 10:45 ` Peter Zijlstra
2019-10-11 10:47 ` Peter Zijlstra
2019-10-11 10:50 ` Peter Zijlstra
2019-10-11 12:59 ` Peter Zijlstra
2019-10-11 13:33 ` Steven Rostedt
2019-10-11 13:45 ` Peter Zijlstra
2019-10-15 13:07 ` Jessica Yu
2019-10-15 13:56 ` Peter Zijlstra
2019-10-15 14:11 ` Peter Zijlstra
2019-10-15 14:13 ` Miroslav Benes
2019-10-15 15:06 ` Joe Lawrence
2019-10-15 15:31 ` Jessica Yu
2019-10-15 22:17 ` Joe Lawrence
2019-10-15 22:27 ` Steven Rostedt
2019-10-16 7:42 ` Peter Zijlstra
2019-10-16 10:15 ` Miroslav Benes
2019-10-21 15:05 ` Josh Poimboeuf
2020-01-20 16:50 ` Josh Poimboeuf
2020-01-21 8:35 ` Miroslav Benes
2020-01-21 16:10 ` Josh Poimboeuf
2020-01-22 10:09 ` Miroslav Benes
2020-01-22 21:42 ` Josh Poimboeuf
2020-01-28 9:28 ` Miroslav Benes
2020-01-28 15:00 ` Josh Poimboeuf
2020-01-28 15:40 ` Petr Mladek
2020-01-28 17:02 ` Josh Poimboeuf
2020-01-29 0:46 ` Jiri Kosina
2020-01-29 2:17 ` Josh Poimboeuf
2020-01-29 3:14 ` Jiri Kosina
2020-01-29 12:28 ` Miroslav Benes
2020-01-29 15:59 ` Josh Poimboeuf
2020-01-30 9:53 ` Petr Mladek
2020-01-30 14:17 ` Josh Poimboeuf
2020-01-31 7:17 ` Petr Mladek
2020-01-22 12:15 ` Miroslav Benes
2020-01-22 15:05 ` Miroslav Benes
2020-01-22 22:03 ` Josh Poimboeuf
2020-01-23 10:19 ` Martin Jambor
2019-10-16 7:49 ` Peter Zijlstra
2019-10-16 10:20 ` Miroslav Benes
2019-10-16 13:29 ` Miroslav Benes
2019-10-18 13:03 ` Jessica Yu
2019-10-18 13:40 ` Petr Mladek
2019-10-21 14:14 ` Jessica Yu
2019-10-21 15:31 ` Josh Poimboeuf
2019-10-22 8:27 ` Miroslav Benes
2019-10-22 14:31 ` Josh Poimboeuf
2019-10-23 9:04 ` Miroslav Benes
2019-10-16 6:51 ` Miroslav Benes
2019-10-16 9:23 ` Peter Zijlstra
2019-10-16 9:36 ` Jessica Yu
2019-10-16 9:51 ` Peter Zijlstra
2019-10-16 12:39 ` Peter Zijlstra
2019-10-22 8:45 ` Miroslav Benes
2019-10-15 14:42 ` Peter Zijlstra
2019-10-15 18:31 ` Peter Zijlstra
2019-10-15 15:51 ` Jessica Yu
2019-10-15 13:28 ` Steven Rostedt
2019-10-15 13:42 ` Peter Zijlstra
2019-10-15 16:09 ` Jessica Yu
2019-10-07 8:17 ` [PATCH v3 6/6] x86/mm: Remove set_kernel_text_r[ow]() Peter Zijlstra
2019-10-08 15:07 ` [PATCH v3 0/6] Rewrite x86/ftrace to use text_poke() Steven Rostedt
2019-10-07 8:25 ` [PATCH v2 0/4] Propagate module notifier errors Peter Zijlstra
2019-10-07 8:25 ` [PATCH v2 1/4] notifier: Fix broken error handling pattern Peter Zijlstra
2019-10-10 22:01 ` Rafael J. Wysocki
2019-10-07 8:25 ` [PATCH v2 2/4] module: Fix up module_notifier return values Peter Zijlstra
2019-10-23 19:25 ` Steven Rostedt
2019-10-07 8:25 ` [PATCH v2 3/4] module: Properly propagate MODULE_STATE_COMING failure Peter Zijlstra
2019-10-08 13:08 ` Miroslav Benes
2019-10-07 8:25 ` [PATCH v2 4/4] jump_label,module: Fix module lifetime for __jump_label_mod_text_reserved Peter Zijlstra
2019-10-23 19:29 ` Steven Rostedt
2019-10-07 8:27 ` [PATCH v2 00/13] Add static_call() Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 01/13] compiler.h: Make __ADDRESSABLE() symbol truly unique Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 02/13] static_call: Add basic static call infrastructure Peter Zijlstra
2019-10-07 11:33 ` Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 03/13] static_call: Add inline " Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 04/13] static_call: Avoid kprobes on inline static_call()s Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 05/13] x86/static_call: Add out-of-line static call implementation Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 06/13] x86/static_call: Add inline static call implementation for x86-64 Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 07/13] static_call: Simple self-test Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 08/13] tracepoints: Use static_call Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 09/13] x86/alternatives: Teach text_poke_bp() to emulate RET Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 10/13] static_call: Add static_cond_call() Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 11/13] static_call: Handle tail-calls Peter Zijlstra
2019-10-07 8:27 ` [PATCH v2 12/13] static_call: Allow early init Peter Zijlstra
2019-10-07 8:27 ` Peter Zijlstra [this message]
2019-10-07 11:33 ` [PATCH v2 00/13] Add static_call() Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 0/9] Variable size jump_label support Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 1/9] jump_label, x86: Strip ASM " Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 2/9] jump_label, x86: Factor out the __jump_table generation Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 3/9] jump_label, x86: Remove init NOP optimization Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 4/9] jump_label, x86: Improve error when we fail expected text Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 5/9] jump_label, x86: Introduce jump_entry_size() Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 6/9] jump_label, x86: Add variable length patching support Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 7/9] jump_label,objtool: Validate variable size jump labels Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 8/9] jump_label,objtool: Generate possible statistics Peter Zijlstra
2019-10-07 8:44 ` [RFC][PATCH 9/9] jump_label, x86: Enable JMP8/NOP2 support Peter Zijlstra
2019-10-07 12:07 ` [RFC][PATCH 0/9] Variable size jump_label support Peter Zijlstra
2019-10-07 12:55 ` Ingo Molnar
2019-10-07 15:08 ` Steven Rostedt
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