Arnaldo Carvalho de Melo 073e5fca53 perf trace: Read thread's COMM from /proc when not set ... We get notifications for threads that gets created while we're tracing, but for preexisting threads we may end not having synthesized them, like when tracing a 'perf trace' session that will use '--pid' to trace some other thread. And besides we should probably stop synthesizing those records and instead read thread information in a lazy way, i.e. just when we need, like done in this patch: Now the 'pid_t' argument in 'perf_event_open' gets translated to a COMM: # perf trace -e perf_event_open perf stat -e cycles -p 31601 0.027 ( 0.027 ms): perf/23393 perf_event_open(attr_uptr: 0x2fdd0d8, pid: 31601 (abrt-dump-journ), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = 3 ^C And in other syscalls containing pid_t without thread->comm_set at the time of the formatting. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-ioeps6dlwst17d6oozc9shtk@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>		2016-04-26 13:15:00 -03:00
..
beauty	perf trace: Read thread's COMM from /proc when not set	2016-04-26 13:15:00 -03:00
strace/groups	perf trace: Add read/write to the file group	2015-09-04 13:22:06 -03:00