Messages in this thread | | | Date | Wed, 3 Mar 2010 22:08:49 +0100 | From | Frederic Weisbecker <> | Subject | Re: [RFC][PATCH 09/11] perf, x86: Implement PERF_SAMPLE_BRANCH_STACK |
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On Wed, Mar 03, 2010 at 05:39:45PM +0100, Peter Zijlstra wrote: > > Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> > --- > arch/x86/kernel/cpu/perf_event.c | 14 +++------- > arch/x86/kernel/cpu/perf_event_intel.c | 10 ++++++- > arch/x86/kernel/cpu/perf_event_intel_ds.c | 16 ++++-------- > arch/x86/kernel/cpu/perf_event_intel_lbr.c | 20 ++++++++------- > include/linux/perf_event.h | 27 +++++++++++++++++--- > kernel/perf_event.c | 38 ++++++++++++++++++++++------- > 6 files changed, 83 insertions(+), 42 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 > @@ -126,8 +126,9 @@ enum perf_event_sample_format { > PERF_SAMPLE_STREAM_ID = 1U << 9, > PERF_SAMPLE_RAW = 1U << 10, > PERF_SAMPLE_REGS = 1U << 11, > + PERF_SAMPLE_BRANCH_STACK = 1U << 12, > > - PERF_SAMPLE_MAX = 1U << 12, /* non-ABI */ > + PERF_SAMPLE_MAX = 1U << 13, /* non-ABI */ > }; > > /* > @@ -395,9 +396,14 @@ enum perf_event_type { > * { struct read_format values; } && PERF_SAMPLE_READ > * { struct pt_regs regs; } && PERF_SAMPLE_REGS > * > - * { u64 nr, > + * { u64 nr; > * u64 ips[nr]; } && PERF_SAMPLE_CALLCHAIN > * > + * { u64 nr; > + * { u64 from, to, flags; > + * } lbr[nr]; } && PERF_SAMPLE_BRANCH_STACK > + * > + * > * # > * # The RAW record below is opaque data wrt the ABI > * # > @@ -469,6 +475,17 @@ struct perf_raw_record { > void *data; > }; > > +struct perf_branch_entry { > + __u64 from; > + __u64 to; > + __u64 flags; > +}; > + > +struct perf_branch_stack { > + __u64 nr; > + struct perf_branch_entry entries[0]; > +}; > + > struct task_struct; > > /** > @@ -803,13 +820,15 @@ struct perf_sample_data { > struct perf_callchain_entry *callchain; > struct perf_raw_record *raw; > struct pt_regs *regs; > + struct perf_branch_stack *branches; > }; > > static inline > void perf_sample_data_init(struct perf_sample_data *data, u64 addr) > { > - data->addr = addr; > - data->raw = NULL; > + data->addr = addr; > + data->raw = NULL; > + data->branches = NULL; > } > > extern void perf_output_sample(struct perf_output_handle *handle, > Index: linux-2.6/kernel/perf_event.c > =================================================================== > --- linux-2.6.orig/kernel/perf_event.c > +++ linux-2.6/kernel/perf_event.c > @@ -3189,12 +3189,9 @@ void perf_output_sample(struct perf_outp > > if (sample_type & PERF_SAMPLE_CALLCHAIN) { > if (data->callchain) { > - int size = 1; > + int size = sizeof(u64); > > - if (data->callchain) > - size += data->callchain->nr; > - > - size *= sizeof(u64); > + size += data->callchain->nr * sizeof(u64); > > perf_output_copy(handle, data->callchain, size); > } else { > @@ -3203,6 +3200,20 @@ void perf_output_sample(struct perf_outp > } > } > > + if (sample_type & PERF_SAMPLE_BRANCH_STACK) { > + if (data->branches) { > + int size = sizeof(u64); > + > + size += data->branches->nr * > + sizeof(struct perf_branch_entry); > + > + perf_output_copy(handle, data->branches, size); > + } else { > + u64 nr = 0; > + perf_output_put(handle, nr); > + } > + } > + > if (sample_type & PERF_SAMPLE_RAW) { > if (data->raw) { > perf_output_put(handle, data->raw->size); > @@ -3291,14 +3302,25 @@ void perf_prepare_sample(struct perf_eve > } > > if (sample_type & PERF_SAMPLE_CALLCHAIN) { > - int size = 1; > + int size = sizeof(u64); > > data->callchain = perf_callchain(regs); > > if (data->callchain) > - size += data->callchain->nr; > + size += data->callchain->nr * sizeof(u64); > + > + header->size += size; > + } > > - header->size += size * sizeof(u64); > + if (sample_type & PERF_SAMPLE_BRANCH_STACK) { > + int size = sizeof(u64); > + > + if (data->branches) { > + size += data->branches->nr * > + sizeof(struct perf_branch_entry); > + } > + > + header->size += size; > }
That looks good to me, (at least the generic part, as I don't know enough the x86 part to tell).
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