leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

perf/core: Add support for PERF_SAMPLE_CODE_PAGE_SIZE

Browse Source 
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
This commit is contained in:
Stephane Eranian 2020-10-01 06:57:49 -07:00 committed by Peter Zijlstra
parent 4cb6a42e4c
commit 995f088efe
4 changed files with 15 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/events/perf_event.h
View File

@ -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) | \

1
include/linux/perf_event.h
View File

@ -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 */

4
include/uapi/linux/perf_event.h
View File

@ -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,

11
kernel/events/core.c
View File

@ -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;