Merge tag 'perf-core-for-mingo-20160530' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
User visible/kernel ABI changes:
- Per event callchain limit: Recently we introduced a sysctl to tune the
max-stack for all events for which callchains were requested:
$ sysctl kernel.perf_event_max_stack
kernel.perf_event_max_stack = 127
Now this patch introduces a way to configure this per event, i.e. this
becomes possible:
$ perf record -e sched:*/max-stack=2/ -e block:*/max-stack=10/ -a
allowing finer tuning of how much buffer space callchains use.
This uses an u16 from the reserved space at the end, leaving another
u16 for future use.
There has been interest in even finer tuning, namely to control the
max stack for kernel and userspace callchains separately. Further
discussion is needed, we may for instance use the remaining u16 for
that and when it is present, assume that the sample_max_stack introduced
in this patch applies for the kernel, and the u16 left is used for
limiting the userspace callchain. (Arnaldo Carvalho de Melo)
Infrastructure changes:
- Adopt get_main_thread from db-export.c (Andi Kleen)
- More prep work for backward ring buffer support (Wang Nan)
- Prep work for supporting SDT (Statically Defined Tracing)
tracepoints (Masami Hiramatsu)
- Add arch/*/include/generated/ to .gitignore (Taeung Song)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
