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| author | Stephane Eranian <eranian@google.com> | 2020-10-01 06:57:49 -0700 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2020-10-29 11:00:39 +0100 |
| commit | 995f088efebe1eba0282a6ffa12411b37f8990c2 (patch) | |
| tree | 9e3185b05657e50aa991790dde6d74ba4dd8ee02 /kernel/events | |
| parent | 4cb6a42e4c4bc1902644eced67563e7405d4588e (diff) | |
| download | linux-995f088efebe1eba0282a6ffa12411b37f8990c2.tar.bz2 | |
perf/core: Add support for PERF_SAMPLE_CODE_PAGE_SIZE
When studying code layout, it is useful to capture the page size of the
sampled code address.
Add a new sample type for code page size.
The new sample type requires collecting the ip. The code page size can
be calculated from the NMI-safe perf_get_page_size().
For large PEBS, it's very unlikely that the mapping is gone for the
earlier PEBS records. Enable the feature for the large PEBS. The worst
case is that page-size '0' is returned.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201001135749.2804-5-kan.liang@linux.intel.com
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/core.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index a796db2f3b57..7f655d19b8c4 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1898,6 +1898,9 @@ static void __perf_event_header_size(struct perf_event *event, u64 sample_type) if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) size += sizeof(data->data_page_size); + if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) + size += sizeof(data->code_page_size); + event->header_size = size; } @@ -6945,6 +6948,9 @@ void perf_output_sample(struct perf_output_handle *handle, if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) perf_output_put(handle, data->data_page_size); + if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) + perf_output_put(handle, data->code_page_size); + if (sample_type & PERF_SAMPLE_AUX) { perf_output_put(handle, data->aux_size); @@ -7125,7 +7131,7 @@ void perf_prepare_sample(struct perf_event_header *header, __perf_event_header__init_id(header, data, event); - if (sample_type & PERF_SAMPLE_IP) + if (sample_type & (PERF_SAMPLE_IP | PERF_SAMPLE_CODE_PAGE_SIZE)) data->ip = perf_instruction_pointer(regs); if (sample_type & PERF_SAMPLE_CALLCHAIN) { @@ -7253,6 +7259,9 @@ void perf_prepare_sample(struct perf_event_header *header, if (sample_type & PERF_SAMPLE_DATA_PAGE_SIZE) data->data_page_size = perf_get_page_size(data->addr); + if (sample_type & PERF_SAMPLE_CODE_PAGE_SIZE) + data->code_page_size = perf_get_page_size(data->ip); + if (sample_type & PERF_SAMPLE_AUX) { u64 size; |