perf/core: Optimize perf_init_event()
authorPeter Zijlstra <peterz@infradead.org>
Thu, 17 Oct 2019 18:31:03 +0000 (20:31 +0200)
committerIngo Molnar <mingo@kernel.org>
Mon, 28 Oct 2019 11:51:02 +0000 (12:51 +0100)
commit66d258c5b048840991de49697264af75f5b09def
treef42f5db64830e46d62bf422dcf6f3d4bc5065ff3
parentdb0503e4f6751f2c719d002ba1becd1811633e6e
perf/core: Optimize perf_init_event()

Andi reported that he was hitting the linear search in
perf_init_event() a lot. Make more agressive use of the IDR lookup to
avoid hitting the linear search.

With exception of PERF_TYPE_SOFTWARE (which relies on a hideous hack),
we can put everything in the IDR. On top of that, we can alias
TYPE_HARDWARE and TYPE_HW_CACHE to TYPE_RAW on the lookup side.

This greatly reduces the chances of hitting the linear search.

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan <kan.liang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kernel/events/core.c