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Merge branch 'perf-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip 

* 'perf-fixes-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
  x86, perf: Check that current->mm is alive before getting user callchain
  perf_event: Fix broken calc_timer_values()
  perf events: Fix slow and broken cgroup context switch code
This commit is contained in:
Linus Torvalds 2011-09-07 13:00:11 -07:00
parent 54d6d53744 20afc60f89
commit b0fb422281
4 changed files with 74 additions and 22 deletions
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3
arch/x86/kernel/cpu/perf_event.c
View File

@ -1900,6 +1900,9 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
perf_callchain_store(entry, regs->ip);
if (!current->mm)
return;
if (perf_callchain_user32(regs, entry))
return;

24
include/linux/perf_event.h
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@ -944,8 +944,10 @@ extern void perf_pmu_unregister(struct pmu *pmu);
extern int perf_num_counters(void);
extern const char *perf_pmu_name(void);
extern void __perf_event_task_sched_in(struct task_struct *task);
extern void __perf_event_task_sched_out(struct task_struct *task, struct task_struct *next);
extern void __perf_event_task_sched_in(struct task_struct *prev,
struct task_struct *task);
extern void __perf_event_task_sched_out(struct task_struct *prev,
struct task_struct *next);
extern int perf_event_init_task(struct task_struct *child);
extern void perf_event_exit_task(struct task_struct *child);
extern void perf_event_free_task(struct task_struct *task);
@ -1059,17 +1061,20 @@ perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
extern struct jump_label_key perf_sched_events;
static inline void perf_event_task_sched_in(struct task_struct *task)
static inline void perf_event_task_sched_in(struct task_struct *prev,
struct task_struct *task)
{
if (static_branch(&perf_sched_events))
__perf_event_task_sched_in(task);
__perf_event_task_sched_in(prev, task);
}
static inline void perf_event_task_sched_out(struct task_struct *task, struct task_struct *next)
static inline void perf_event_task_sched_out(struct task_struct *prev,
struct task_struct *next)
{
perf_sw_event(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, NULL, 0);
__perf_event_task_sched_out(task, next);
if (static_branch(&perf_sched_events))
__perf_event_task_sched_out(prev, next);
}
extern void perf_event_mmap(struct vm_area_struct *vma);
@ -1139,10 +1144,11 @@ extern void perf_event_disable(struct perf_event *event);
extern void perf_event_task_tick(void);
#else
static inline void
perf_event_task_sched_in(struct task_struct *task) { }
perf_event_task_sched_in(struct task_struct *prev,
struct task_struct *task) { }
static inline void
perf_event_task_sched_out(struct task_struct *task,
struct task_struct *next) { }
perf_event_task_sched_out(struct task_struct *prev,
struct task_struct *next) { }
static inline int perf_event_init_task(struct task_struct *child) { return 0; }
static inline void perf_event_exit_task(struct task_struct *child) { }
static inline void perf_event_free_task(struct task_struct *task) { }

67
kernel/events/core.c
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@ -399,14 +399,54 @@ void perf_cgroup_switch(struct task_struct *task, int mode)
local_irq_restore(flags);
}
static inline void perf_cgroup_sched_out(struct task_struct *task)
static inline void perf_cgroup_sched_out(struct task_struct *task,
struct task_struct *next)
{
perf_cgroup_switch(task, PERF_CGROUP_SWOUT);
struct perf_cgroup *cgrp1;
struct perf_cgroup *cgrp2 = NULL;
/*
* we come here when we know perf_cgroup_events > 0
*/
cgrp1 = perf_cgroup_from_task(task);
/*
* next is NULL when called from perf_event_enable_on_exec()
* that will systematically cause a cgroup_switch()
*/
if (next)
cgrp2 = perf_cgroup_from_task(next);
/*
* only schedule out current cgroup events if we know
* that we are switching to a different cgroup. Otherwise,
* do no touch the cgroup events.
*/
if (cgrp1 != cgrp2)
perf_cgroup_switch(task, PERF_CGROUP_SWOUT);
}
static inline void perf_cgroup_sched_in(struct task_struct *task)
static inline void perf_cgroup_sched_in(struct task_struct *prev,
struct task_struct *task)
{
perf_cgroup_switch(task, PERF_CGROUP_SWIN);
struct perf_cgroup *cgrp1;
struct perf_cgroup *cgrp2 = NULL;
/*
* we come here when we know perf_cgroup_events > 0
*/
cgrp1 = perf_cgroup_from_task(task);
/* prev can never be NULL */
cgrp2 = perf_cgroup_from_task(prev);
/*
* only need to schedule in cgroup events if we are changing
* cgroup during ctxsw. Cgroup events were not scheduled
* out of ctxsw out if that was not the case.
*/
if (cgrp1 != cgrp2)
perf_cgroup_switch(task, PERF_CGROUP_SWIN);
}
static inline int perf_cgroup_connect(int fd, struct perf_event *event,
@ -518,11 +558,13 @@ static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx)
{
}
static inline void perf_cgroup_sched_out(struct task_struct *task)
static inline void perf_cgroup_sched_out(struct task_struct *task,
struct task_struct *next)
{
}
static inline void perf_cgroup_sched_in(struct task_struct *task)
static inline void perf_cgroup_sched_in(struct task_struct *prev,
struct task_struct *task)
{
}
@ -1988,7 +2030,7 @@ void __perf_event_task_sched_out(struct task_struct *task,
* cgroup event are system-wide mode only
*/
if (atomic_read(&__get_cpu_var(perf_cgroup_events)))
perf_cgroup_sched_out(task);
perf_cgroup_sched_out(task, next);
}
static void task_ctx_sched_out(struct perf_event_context *ctx)
@ -2153,7 +2195,8 @@ static void perf_event_context_sched_in(struct perf_event_context *ctx,
* accessing the event control register. If a NMI hits, then it will
* keep the event running.
*/
void __perf_event_task_sched_in(struct task_struct *task)
void __perf_event_task_sched_in(struct task_struct *prev,
struct task_struct *task)
{
struct perf_event_context *ctx;
int ctxn;
@ -2171,7 +2214,7 @@ void __perf_event_task_sched_in(struct task_struct *task)
* cgroup event are system-wide mode only
*/
if (atomic_read(&__get_cpu_var(perf_cgroup_events)))
perf_cgroup_sched_in(task);
perf_cgroup_sched_in(prev, task);
}
static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count)
@ -2427,7 +2470,7 @@ static void perf_event_enable_on_exec(struct perf_event_context *ctx)
* ctxswin cgroup events which are already scheduled
* in.
*/
perf_cgroup_sched_out(current);
perf_cgroup_sched_out(current, NULL);
raw_spin_lock(&ctx->lock);
task_ctx_sched_out(ctx);
@ -3353,8 +3396,8 @@ static int perf_event_index(struct perf_event *event)
}
static void calc_timer_values(struct perf_event *event,
u64 *running,
u64 *enabled)
u64 *enabled,
u64 *running)
{
u64 now, ctx_time;

2
kernel/sched.c
View File

@ -3065,7 +3065,7 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
local_irq_disable();
#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
perf_event_task_sched_in(current);
perf_event_task_sched_in(prev, current);
#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
local_irq_enable();
#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */