diff options
| author | David Miller <davem@davemloft.net> | 2018-10-30 22:24:04 -0700 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2018-10-31 10:18:01 -0300 |
| commit | 4f8f382e635707ddaddf8269a116e4f8cc8835c0 (patch) | |
| tree | c5fceab005fc1d526f7ce91d2323d52d530e6fb6 /include | |
| parent | ff27a06af6ffd3f49b9e193eb68f487ad76651e1 (diff) | |
perf tools: Don't clone maps from parent when synthesizing forks
When synthesizing FORK events, we are trying to create thread objects
for the already running tasks on the machine.
Normally, for a kernel FORK event, we want to clone the parent's maps
because that is what the kernel just did.
But when synthesizing, this should not be done. If we do, we end up
with overlapping maps as we process the sythesized MMAP2 events that
get delivered shortly thereafter.
Use the FORK event misc flags in an internal way to signal this
situation, so we can elide the map clone when appropriate.
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joe Mario <jmario@redhat.com>
Link: http://lkml.kernel.org/r/20181030.222404.2085088822877051075.davem@davemloft.net
[ Added comment about flag use in machine__process_fork_event(),
use ternary op in thread__clone_map_groups() as suggested by Jiri ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/uapi/linux/perf_event.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index f35eb72739c0..9de8780ac8d9 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -646,10 +646,12 @@ struct perf_event_mmap_page { * * PERF_RECORD_MISC_MMAP_DATA - PERF_RECORD_MMAP* events * PERF_RECORD_MISC_COMM_EXEC - PERF_RECORD_COMM event + * PERF_RECORD_MISC_FORK_EXEC - PERF_RECORD_FORK event (perf internal) * PERF_RECORD_MISC_SWITCH_OUT - PERF_RECORD_SWITCH* events */ #define PERF_RECORD_MISC_MMAP_DATA (1 << 13) #define PERF_RECORD_MISC_COMM_EXEC (1 << 13) +#define PERF_RECORD_MISC_FORK_EXEC (1 << 13) #define PERF_RECORD_MISC_SWITCH_OUT (1 << 13) /* * These PERF_RECORD_MISC_* flags below are safely reused |