linux_dsm_epyc7002/arch/arm64
Wang Nan 1879445dfa perf/core: Set event's default ::overflow_handler()
Set a default event->overflow_handler in perf_event_alloc() so don't
need to check event->overflow_handler in __perf_event_overflow().
Following commits can give a different default overflow_handler.

Initial idea comes from Peter:

  http://lkml.kernel.org/r/20130708121557.GA17211@twins.programming.kicks-ass.net

Since the default value of event->overflow_handler is not NULL, existing
'if (!overflow_handler)' checks need to be changed.

is_default_overflow_handler() is introduced for this.

No extra performance overhead is introduced into the hot path because in the
original code we still need to read this handler from memory. A conditional
branch is avoided so actually we remove some instructions.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <pi3orama@163.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.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>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1459147292-239310-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-31 10:30:47 +02:00
..
boot arm64: kbuild: make "make install" not depend on vmlinux 2016-02-19 10:33:35 +00:00
configs
crypto arm/arm64: crypto: assure that ECB modes don't require an IV 2016-02-15 15:48:29 +00:00
include Merge branch 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-14 16:58:50 -07:00
kernel perf/core: Set event's default ::overflow_handler() 2016-03-31 10:30:47 +02:00
kvm arm/arm64: KVM: Fix ioctl error handling 2016-02-29 09:56:40 +00:00
lib arm64/efi: Make strnlen() available to the EFI namespace 2016-02-16 10:32:10 +00:00
mm arm64: hugetlb: partial revert of 66b3923a1a 2016-03-09 15:29:29 +00:00
net
xen
Kconfig
Kconfig.debug
Kconfig.platforms
Makefile arm64: kbuild: make "make install" not depend on vmlinux 2016-02-19 10:33:35 +00:00