From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: paulus <paulus@samba.org>,
stephane eranian <eranian@googlemail.com>,
Robert Richter <robert.richter@amd.com>,
Will Deacon <will.deacon@arm.com>,
Paul Mundt <lethal@linux-sh.org>,
Frederic Weisbecker <fweisbec@gmail.com>,
Cyrill Gorcunov <gorcunov@gmail.com>,
Lin Ming <ming.m.lin@intel.com>,
Yanmin <yanmin_zhang@linux.intel.com>,
Deng-Cheng Zhu <dengcheng.zhu@gmail.com>,
David Miller <davem@davemloft.net>, Ingo Molnar <mingo@elte.hu>
Cc: linux-kernel@vger.kernel.org, Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: [RFC][PATCH 12/19] perf: Remove the swevent hash-table from the cpu context
Date: Tue, 07 Sep 2010 18:46:45 +0200 [thread overview]
Message-ID: <20100907165011.890202348@chello.nl> (raw)
In-Reply-To: 20100907164633.879932949@chello.nl
[-- Attachment #1: perf-pmu-context-5.patch --]
[-- Type: text/plain, Size: 9328 bytes --]
Separate the swevent hash-table from the cpu_context bits in preparation
for per pmu cpu contexts.
This keeps the swevent hash a global entity.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
include/linux/perf_event.h | 6 --
kernel/perf_event.c | 104 +++++++++++++++++++++++++--------------------
2 files changed, 58 insertions(+), 52 deletions(-)
Index: linux-2.6/include/linux/perf_event.h
===================================================================
--- linux-2.6.orig/include/linux/perf_event.h
+++ linux-2.6/include/linux/perf_event.h
@@ -866,12 +866,6 @@ struct perf_cpu_context {
struct perf_event_context *task_ctx;
int active_oncpu;
int exclusive;
- struct swevent_hlist *swevent_hlist;
- struct mutex hlist_mutex;
- int hlist_refcount;
-
- /* Recursion avoidance in each contexts */
- int recursion[PERF_NR_CONTEXTS];
};
struct perf_output_handle {
Index: linux-2.6/kernel/perf_event.c
===================================================================
--- linux-2.6.orig/kernel/perf_event.c
+++ linux-2.6/kernel/perf_event.c
@@ -4154,6 +4154,17 @@ int perf_event_overflow(struct perf_even
* Generic software event infrastructure
*/
+struct swevent_htable {
+ struct swevent_hlist *swevent_hlist;
+ struct mutex hlist_mutex;
+ int hlist_refcount;
+
+ /* Recursion avoidance in each contexts */
+ int recursion[PERF_NR_CONTEXTS];
+};
+
+static DEFINE_PER_CPU(struct swevent_htable, swevent_htable);
+
/*
* We directly increment event->count and keep a second value in
* event->hw.period_left to count intervals. This period event
@@ -4286,11 +4297,11 @@ __find_swevent_head(struct swevent_hlist
/* For the read side: events when they trigger */
static inline struct hlist_head *
-find_swevent_head_rcu(struct perf_cpu_context *ctx, u64 type, u32 event_id)
+find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id)
{
struct swevent_hlist *hlist;
- hlist = rcu_dereference(ctx->swevent_hlist);
+ hlist = rcu_dereference(swhash->swevent_hlist);
if (!hlist)
return NULL;
@@ -4299,7 +4310,7 @@ find_swevent_head_rcu(struct perf_cpu_co
/* For the event head insertion and removal in the hlist */
static inline struct hlist_head *
-find_swevent_head(struct perf_cpu_context *ctx, struct perf_event *event)
+find_swevent_head(struct swevent_htable *swhash, struct perf_event *event)
{
struct swevent_hlist *hlist;
u32 event_id = event->attr.config;
@@ -4310,7 +4321,7 @@ find_swevent_head(struct perf_cpu_contex
* and release. Which makes the protected version suitable here.
* The context lock guarantees that.
*/
- hlist = rcu_dereference_protected(ctx->swevent_hlist,
+ hlist = rcu_dereference_protected(swhash->swevent_hlist,
lockdep_is_held(&event->ctx->lock));
if (!hlist)
return NULL;
@@ -4323,17 +4334,13 @@ static void do_perf_sw_event(enum perf_t
struct perf_sample_data *data,
struct pt_regs *regs)
{
- struct perf_cpu_context *cpuctx;
+ struct swevent_htable *swhash = &__get_cpu_var(swevent_htable);
struct perf_event *event;
struct hlist_node *node;
struct hlist_head *head;
- cpuctx = &__get_cpu_var(perf_cpu_context);
-
rcu_read_lock();
-
- head = find_swevent_head_rcu(cpuctx, type, event_id);
-
+ head = find_swevent_head_rcu(swhash, type, event_id);
if (!head)
goto end;
@@ -4347,17 +4354,17 @@ static void do_perf_sw_event(enum perf_t
int perf_swevent_get_recursion_context(void)
{
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct swevent_htable *swhash = &__get_cpu_var(swevent_htable);
- return get_recursion_context(cpuctx->recursion);
+ return get_recursion_context(swhash->recursion);
}
EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context);
void inline perf_swevent_put_recursion_context(int rctx)
{
- struct perf_cpu_context *cpuctx = &__get_cpu_var(perf_cpu_context);
+ struct swevent_htable *swhash = &__get_cpu_var(swevent_htable);
- put_recursion_context(cpuctx->recursion, rctx);
+ put_recursion_context(swhash->recursion, rctx);
}
void __perf_sw_event(u32 event_id, u64 nr, int nmi,
@@ -4385,12 +4392,10 @@ static void perf_swevent_read(struct per
static int perf_swevent_add(struct perf_event *event, int flags)
{
+ struct swevent_htable *swhash = &__get_cpu_var(swevent_htable);
struct hw_perf_event *hwc = &event->hw;
- struct perf_cpu_context *cpuctx;
struct hlist_head *head;
- cpuctx = &__get_cpu_var(perf_cpu_context);
-
if (hwc->sample_period) {
hwc->last_period = hwc->sample_period;
perf_swevent_set_period(event);
@@ -4398,7 +4403,7 @@ static int perf_swevent_add(struct perf_
hwc->state = !(flags & PERF_EF_START);
- head = find_swevent_head(cpuctx, event);
+ head = find_swevent_head(swhash, event);
if (WARN_ON_ONCE(!head))
return -EINVAL;
@@ -4424,10 +4429,10 @@ static void perf_swevent_stop(struct per
/* Deref the hlist from the update side */
static inline struct swevent_hlist *
-swevent_hlist_deref(struct perf_cpu_context *cpuctx)
+swevent_hlist_deref(struct swevent_htable *swhash)
{
- return rcu_dereference_protected(cpuctx->swevent_hlist,
- lockdep_is_held(&cpuctx->hlist_mutex));
+ return rcu_dereference_protected(swhash->swevent_hlist,
+ lockdep_is_held(&swhash->hlist_mutex));
}
static void swevent_hlist_release_rcu(struct rcu_head *rcu_head)
@@ -4438,27 +4443,27 @@ static void swevent_hlist_release_rcu(st
kfree(hlist);
}
-static void swevent_hlist_release(struct perf_cpu_context *cpuctx)
+static void swevent_hlist_release(struct swevent_htable *swhash)
{
- struct swevent_hlist *hlist = swevent_hlist_deref(cpuctx);
+ struct swevent_hlist *hlist = swevent_hlist_deref(swhash);
if (!hlist)
return;
- rcu_assign_pointer(cpuctx->swevent_hlist, NULL);
+ rcu_assign_pointer(swhash->swevent_hlist, NULL);
call_rcu(&hlist->rcu_head, swevent_hlist_release_rcu);
}
static void swevent_hlist_put_cpu(struct perf_event *event, int cpu)
{
- struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+ struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu);
- mutex_lock(&cpuctx->hlist_mutex);
+ mutex_lock(&swhash->hlist_mutex);
- if (!--cpuctx->hlist_refcount)
- swevent_hlist_release(cpuctx);
+ if (!--swhash->hlist_refcount)
+ swevent_hlist_release(swhash);
- mutex_unlock(&cpuctx->hlist_mutex);
+ mutex_unlock(&swhash->hlist_mutex);
}
static void swevent_hlist_put(struct perf_event *event)
@@ -4476,12 +4481,12 @@ static void swevent_hlist_put(struct per
static int swevent_hlist_get_cpu(struct perf_event *event, int cpu)
{
- struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+ struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu);
int err = 0;
- mutex_lock(&cpuctx->hlist_mutex);
+ mutex_lock(&swhash->hlist_mutex);
- if (!swevent_hlist_deref(cpuctx) && cpu_online(cpu)) {
+ if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) {
struct swevent_hlist *hlist;
hlist = kzalloc(sizeof(*hlist), GFP_KERNEL);
@@ -4489,11 +4494,11 @@ static int swevent_hlist_get_cpu(struct
err = -ENOMEM;
goto exit;
}
- rcu_assign_pointer(cpuctx->swevent_hlist, hlist);
+ rcu_assign_pointer(swhash->swevent_hlist, hlist);
}
- cpuctx->hlist_refcount++;
+ swhash->hlist_refcount++;
exit:
- mutex_unlock(&cpuctx->hlist_mutex);
+ mutex_unlock(&swhash->hlist_mutex);
return err;
}
@@ -5891,12 +5896,15 @@ int perf_event_init_task(struct task_str
static void __init perf_event_init_all_cpus(void)
{
- int cpu;
struct perf_cpu_context *cpuctx;
+ struct swevent_htable *swhash;
+ int cpu;
for_each_possible_cpu(cpu) {
+ swhash = &per_cpu(swevent_htable, cpu);
+ mutex_init(&swhash->hlist_mutex);
+
cpuctx = &per_cpu(perf_cpu_context, cpu);
- mutex_init(&cpuctx->hlist_mutex);
__perf_event_init_context(&cpuctx->ctx, NULL);
}
}
@@ -5904,18 +5912,21 @@ static void __init perf_event_init_all_c
static void __cpuinit perf_event_init_cpu(int cpu)
{
struct perf_cpu_context *cpuctx;
+ struct swevent_htable *swhash;
cpuctx = &per_cpu(perf_cpu_context, cpu);
- mutex_lock(&cpuctx->hlist_mutex);
- if (cpuctx->hlist_refcount > 0) {
+ swhash = &per_cpu(swevent_htable, cpu);
+
+ mutex_lock(&swhash->hlist_mutex);
+ if (swhash->hlist_refcount > 0) {
struct swevent_hlist *hlist;
- hlist = kzalloc(sizeof(*hlist), GFP_KERNEL);
- WARN_ON_ONCE(!hlist);
- rcu_assign_pointer(cpuctx->swevent_hlist, hlist);
+ hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu));
+ WARN_ON(!hlist);
+ rcu_assign_pointer(swhash->swevent_hlist, hlist);
}
- mutex_unlock(&cpuctx->hlist_mutex);
+ mutex_unlock(&swhash->hlist_mutex);
}
#ifdef CONFIG_HOTPLUG_CPU
@@ -5933,11 +5944,12 @@ static void __perf_event_exit_cpu(void *
static void perf_event_exit_cpu(int cpu)
{
struct perf_cpu_context *cpuctx = &per_cpu(perf_cpu_context, cpu);
+ struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu);
struct perf_event_context *ctx = &cpuctx->ctx;
- mutex_lock(&cpuctx->hlist_mutex);
- swevent_hlist_release(cpuctx);
- mutex_unlock(&cpuctx->hlist_mutex);
+ mutex_lock(&swhash->hlist_mutex);
+ swevent_hlist_release(swhash);
+ mutex_unlock(&swhash->hlist_mutex);
mutex_lock(&ctx->mutex);
smp_call_function_single(cpu, __perf_event_exit_cpu, NULL, 1);
next prev parent reply other threads:[~2010-09-07 16:56 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-07 16:46 [RFC][PATCH 00/19] perf pmu interface changes -v4 Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 01/19] perf: Fix CPU hotplug Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 02/19] perf: deconstify struct pmu Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 03/19] perf: register pmu implementations Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 04/19] perf: Unindent labels Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 05/19] perf: Reduce perf_disable() usage Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 06/19] perf: Per PMU disable Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 07/19] perf: Default PMU ops Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 08/19] perf: Shrink hw_perf_event Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 09/19] perf: Rework the PMU methods Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 10/19] perf: Remove the sysfs bits Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 11/19] perf: Separate find_get_context() from event initialization Peter Zijlstra
2010-09-07 16:46 ` Peter Zijlstra [this message]
2010-09-07 16:46 ` [RFC][PATCH 13/19] perf: Per cpu-context rotation timer Peter Zijlstra
2010-09-07 17:07 ` Peter Zijlstra
2010-09-07 17:33 ` Thomas Gleixner
2010-09-07 17:36 ` Peter Zijlstra
2010-09-08 13:50 ` Thomas Gleixner
2010-09-08 13:56 ` Peter Zijlstra
2010-09-07 17:08 ` Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 14/19] perf: Per-pmu-per-cpu contexts Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 15/19] perf: Move some code around Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 16/19] perf: Clean up perf_event_context allocation Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 17/19] perf: Multiple task contexts Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 18/19] perf: Provide a separate task context for swevents Peter Zijlstra
2010-09-07 16:46 ` [RFC][PATCH 19/19] perf: Optimize context ops Peter Zijlstra
2010-09-10 4:39 ` [RFC][PATCH 00/19] perf pmu interface changes -v4 Paul Mackerras
2010-09-10 7:43 ` Peter Zijlstra
2010-09-14 16:56 ` Peter Zijlstra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20100907165011.890202348@chello.nl \
--to=a.p.zijlstra@chello.nl \
--cc=davem@davemloft.net \
--cc=dengcheng.zhu@gmail.com \
--cc=eranian@googlemail.com \
--cc=fweisbec@gmail.com \
--cc=gorcunov@gmail.com \
--cc=lethal@linux-sh.org \
--cc=linux-kernel@vger.kernel.org \
--cc=ming.m.lin@intel.com \
--cc=mingo@elte.hu \
--cc=paulus@samba.org \
--cc=robert.richter@amd.com \
--cc=will.deacon@arm.com \
--cc=yanmin_zhang@linux.intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.