diff options
| author | Andy Lutomirski <luto@kernel.org> | 2015-10-05 17:48:23 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-10-09 09:41:13 +0200 |
| commit | 39b48e575e92e31251b74b4b48cea2129cee90bd (patch) | |
| tree | 0a57f6053546e0a191920e99415ad9e605231aeb /net/lapb/lapb_subr.c | |
| parent | dd636071c3d8044c802b7a365e9934724a929530 (diff) | |
x86/entry: Split and inline prepare_exit_to_usermode()
GCC is unable to properly optimize functions that have a very
short likely case and a longer and register-heavier cold part --
it fails to sink all of the register saving and stack frame
setup code into the unlikely part.
Help it out with prepare_exit_to_usermode() by splitting it into
two parts and inline the hot part.
Saves 6-8 cycles for compat syscalls.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/9fc53eda4a5b924070952f12fa4ae3e477640a07.1444091585.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/lapb/lapb_subr.c')
0 files changed, 0 insertions, 0 deletions