diff options
| author | Sandipan Das <sandipan.das@amd.com> | 2022-08-11 18:00:00 +0530 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2022-08-27 00:05:45 +0200 |
| commit | 93315e46b000fc80fff5d53c3f444417fb3df6de (patch) | |
| tree | e0f87db286a0c398c45aac05387b06407942ca94 /include/uapi | |
| parent | 245268c19f701c7222dedcb6a383bc73d63925d4 (diff) | |
| download | linux-stable-93315e46b000fc80fff5d53c3f444417fb3df6de.tar.gz linux-stable-93315e46b000fc80fff5d53c3f444417fb3df6de.tar.bz2 linux-stable-93315e46b000fc80fff5d53c3f444417fb3df6de.zip | |
perf/core: Add speculation info to branch entries
Add a new "spec" bitfield to branch entries for providing speculation
information. This will be populated using hints provided by branch sampling
features on supported hardware. The following cases are covered:
* No branch speculation information is available
* Branch is speculative but taken on the wrong path
* Branch is non-speculative but taken on the correct path
* Branch is speculative and taken on the correct path
Suggested-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/834088c302faf21c7b665031dd111f424e509a64.1660211399.git.sandipan.das@amd.com
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/linux/perf_event.h | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index 03b370062741..30a4723aefd4 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -256,6 +256,17 @@ enum { PERF_BR_MAX, }; +/* + * Common branch speculation outcome classification + */ +enum { + PERF_BR_SPEC_NA = 0, /* Not available */ + PERF_BR_SPEC_WRONG_PATH = 1, /* Speculative but on wrong path */ + PERF_BR_NON_SPEC_CORRECT_PATH = 2, /* Non-speculative but on correct path */ + PERF_BR_SPEC_CORRECT_PATH = 3, /* Speculative and on correct path */ + PERF_BR_SPEC_MAX, +}; + #define PERF_SAMPLE_BRANCH_PLM_ALL \ (PERF_SAMPLE_BRANCH_USER|\ PERF_SAMPLE_BRANCH_KERNEL|\ @@ -1363,6 +1374,7 @@ union perf_mem_data_src { * abort: aborting a hardware transaction * cycles: cycles from last branch (or 0 if not supported) * type: branch type + * spec: branch speculation info (or 0 if not supported) */ struct perf_branch_entry { __u64 from; @@ -1373,7 +1385,8 @@ struct perf_branch_entry { abort:1, /* transaction abort */ cycles:16, /* cycle count to last branch */ type:4, /* branch type */ - reserved:40; + spec:2, /* branch speculation info */ + reserved:38; }; union perf_sample_weight { |