diff options
| author | Andy Lutomirski <luto@kernel.org> | 2015-11-12 12:59:04 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-11-24 09:56:44 +0100 |
| commit | 478dc89cf316697e8029411a64ea2b30c528434d (patch) | |
| tree | f2d9b65ba366429ab2f8932e01d05a96d4efe492 /drivers/watchdog | |
| parent | 2671c3e4fe2a34bd9bf2eecdf5d1149d4b55dbdf (diff) | |
x86/entry/64: Bypass enter_from_user_mode on non-context-tracking boots
On CONFIG_CONTEXT_TRACKING kernels that have context tracking
disabled at runtime (which includes most distro kernels), we
still have the overhead of a call to enter_from_user_mode in
interrupt and exception entries.
If jump labels are available, this uses the jump label
infrastructure to skip the call.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
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: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/73ee804fff48cd8c66b65b724f9f728a11a8c686.1447361906.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'drivers/watchdog')
0 files changed, 0 insertions, 0 deletions