linux-stable.git/include/linux/perf_event.h, branch linux-2.6.37.y

perf: Fix duplicate events with multiple-pmu vs software events

2010-12-08T19:14:08+00:00

Because the multi-pmu bits can share contexts between struct pmu
instances we could get duplicate events by iterating the pmu list.

Signed-off-by: Peter Zijlstra 
Signed-off-by: Thomas Gleixner 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf: Fix the software context switch counter

2010-11-26T14:00:59+00:00

Stephane noticed that because the perf_sw_event() call is inside the
perf_event_task_sched_out() call it won't get called unless we
have a per-task counter.

Reported-by: Stephane Eranian 
Signed-off-by: Peter Zijlstra 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf: Fix inherit vs. context rotation bug

2010-11-26T14:00:56+00:00

It was found that sometimes children of tasks with inherited events had
one extra event. Eventually it turned out to be due to the list rotation
no being exclusive with the list iteration in the inheritance code.

Cure this by temporarily disabling the rotation while we inherit the events.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Peter Zijlstra 
LKML-Reference: 
Cc: 
Signed-off-by: Ingo Molnar

perf_events: Fix time tracking in samples

2010-11-10T21:58:39+00:00

This patch corrects time tracking in samples. Without this patch
both time_enabled and time_running are bogus when user asks for
PERF_SAMPLE_READ.

One uses PERF_SAMPLE_READ to sample the values of other counters
in each sample. Because of multiplexing, it is necessary to know
both time_enabled, time_running to be able to scale counts correctly.

In this second version of the patch, we maintain a shadow
copy of ctx->time which allows us to compute ctx->time without
calling update_context_time() from NMI context. We avoid the
issue that update_context_time() must always be called with
ctx->lock held.

We do not keep shadow copies of the other event timings
because if the lead event is overflowing then it is active
and thus it's been scheduled in via event_sched_in() in
which case neither tstamp_stopped, tstamp_running can be modified.

This timing logic only applies to samples when PERF_SAMPLE_READ
is used.

Note that this patch does not address timing issues related
to sampling inheritance between tasks. This will be addressed
in a future patch.

With this patch, the libpfm4 example task_smpl now reports
correct counts (shown on 2.4GHz Core 2):

$ task_smpl -p 2400000000 -e unhalted_core_cycles:u,instructions_retired:u,baclears noploop 5
noploop for 5 seconds
IIP:0x000000004006d6 PID:5596 TID:5596 TIME:466,210,211,430 STREAM_ID:33 PERIOD:2,400,000,000 ENA=1,010,157,814 RUN=1,010,157,814 NR=3
2,400,000,254 unhalted_core_cycles:u (33)
2,399,273,744 instructions_retired:u (34)
53,340 baclears (35)

Signed-off-by: Stephane Eranian
Signed-off-by: Peter Zijlstra
LKML-Reference: <4cc6e14b.1e07e30a.256e.5190@mx.google.com>
Signed-off-by: Ingo Molnar

jump_label: Add COND_STMT(), reducer wrappery

2010-10-18T17:59:01+00:00

The use of the JUMP_LABEL() construct ends up creating endless silly
wrappers, create a higher level construct to reduce this clutter.

Signed-off-by: Peter Zijlstra 
Cc: Jason Baron 
Cc: Steven Rostedt 
Cc: Arnaldo Carvalho de Melo 
Cc: Frederic Weisbecker 
Cc: Paul Mackerras 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf: Optimize sw events

2010-10-18T17:58:59+00:00

Acked-by: Frederic Weisbecker 
Signed-off-by: Peter Zijlstra 
LKML-Reference: 
Signed-off-by: Ingo Molnar

perf: Use jump_labels to optimize the scheduler hooks

2010-10-18T17:58:58+00:00

Trades a call + conditional + ret for an unconditional jmp.

Acked-by: Frederic Weisbecker 
Signed-off-by: Peter Zijlstra 
LKML-Reference: <20101014203625.501657727@chello.nl>
Signed-off-by: Ingo Molnar

perf, hw_breakpoint: Fix crash in hw_breakpoint creation

2010-10-18T17:58:55+00:00

hw_breakpoint creation needs to account stuff per-task to ensure there
is always sufficient hardware resources to back these things due to
ptrace.

With the perf per pmu context changes the event initialization no
longer has access to the event context, for the simple reason that we
need to first find the pmu (result of initialization) before we can
find the context.

This makes hw_breakpoints unhappy, because it can no longer do per
task accounting, cure this by frobbing a task pointer in the event::hw
bits for now...

Signed-off-by: Peter Zijlstra 
Cc: Frederic Weisbecker 
LKML-Reference: <20101014203625.391543667@chello.nl>
Signed-off-by: Ingo Molnar

irq_work: Add generic hardirq context callbacks

2010-10-18T17:58:50+00:00

Provide a mechanism that allows running code in IRQ context. It is
most useful for NMI code that needs to interact with the rest of the
system -- like wakeup a task to drain buffers.

Perf currently has such a mechanism, so extract that and provide it as
a generic feature, independent of perf so that others may also
benefit.

The IRQ context callback is generated through self-IPIs where
possible, or on architectures like powerpc the decrementer (the
built-in timer facility) is set to generate an interrupt immediately.

Architectures that don't have anything like this get to do with a
callback from the timer tick. These architectures can call
irq_work_run() at the tail of any IRQ handlers that might enqueue such
work (like the perf IRQ handler) to avoid undue latencies in
processing the work.

Signed-off-by: Peter Zijlstra 
Acked-by: Kyle McMartin 
Acked-by: Martin Schwidefsky 
[ various fixes ]
Signed-off-by: Huang Ying 
LKML-Reference: <1287036094.7768.291.camel@yhuang-dev>
Signed-off-by: Ingo Molnar

Merge remote branch 'tip/perf/core' into oprofile/core

2010-10-15T10:45:00+00:00

Conflicts:
	arch/arm/oprofile/common.c
	kernel/perf_event.c