From: Stephane Eranian <[email protected]> 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. Co-developed-by: Kan Liang <[email protected]> Signed-off-by: Kan Liang <[email protected]> Signed-off-by: Stephane Eranian <[email protected]> --- arch/x86/events/perf_event.h | 2 +- include/linux/perf_event.h | 1 + include/uapi/linux/perf_event.h | 4 +++- kernel/events/core.c | 11 ++++++++++- 4 files changed, 15 insertions(+), 3 deletions(-) diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index 345442410a4d..10629ef1b626 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -132,7 +132,7 @@ struct amd_nb { PERF_SAMPLE_DATA_SRC | PERF_SAMPLE_IDENTIFIER | \ PERF_SAMPLE_TRANSACTION | PERF_SAMPLE_PHYS_ADDR | \ PERF_SAMPLE_REGS_INTR | PERF_SAMPLE_REGS_USER | \ - PERF_SAMPLE_PERIOD) + PERF_SAMPLE_PERIOD | PERF_SAMPLE_CODE_PAGE_SIZE) #define PEBS_GP_REGS \ ((1ULL << PERF_REG_X86_AX) | \ diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 7e3785dd27d9..e533b03af053 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1035,6 +1035,7 @@ struct perf_sample_data { u64 phys_addr; u64 cgroup; u64 data_page_size; + u64 code_page_size; } ____cacheline_aligned; /* default value for data source */ diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index cc6ea346e9f9..c2f20ee3124d 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -144,8 +144,9 @@ enum perf_event_sample_format { PERF_SAMPLE_AUX = 1U << 20, PERF_SAMPLE_CGROUP = 1U << 21, PERF_SAMPLE_DATA_PAGE_SIZE = 1U << 22, + PERF_SAMPLE_CODE_PAGE_SIZE = 1U << 23, - PERF_SAMPLE_MAX = 1U << 23, /* non-ABI */ + PERF_SAMPLE_MAX = 1U << 24, /* non-ABI */ __PERF_SAMPLE_CALLCHAIN_EARLY = 1ULL << 63, /* non-ABI; internal use */ }; @@ -898,6 +899,7 @@ enum perf_event_type { * { u64 size; * char data[size]; } && PERF_SAMPLE_AUX * { u64 data_page_size;} && PERF_SAMPLE_DATA_PAGE_SIZE + * { u64 code_page_size;} && PERF_SAMPLE_CODE_PAGE_SIZE * }; */ PERF_RECORD_SAMPLE = 9, diff --git a/kernel/events/core.c b/kernel/events/core.c index dd329a8f99f7..5fb27cb845fb 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; } @@ -6944,6 +6947,9 @@ 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); @@ -7114,7 +7120,7 @@ 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) { @@ -7242,6 +7248,9 @@ 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; -- 2.17.1
