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| author | Andy Lutomirski <luto@kernel.org> | 2015-10-06 02:48:21 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-10-09 09:41:12 +0200 |
| commit | 4aabd140f9cbe0361401a1368bac74df1010abf5 (patch) | |
| tree | 0cfc24055bbc52ad4958ca3643be2d28897460c3 /arch/x86/entry/common.c | |
| parent | x86/entry: Micro-optimize compat fast syscall arg fetch (diff) | |
| download | linux-4aabd140f9cbe0361401a1368bac74df1010abf5.tar.xz linux-4aabd140f9cbe0361401a1368bac74df1010abf5.zip | |
x86/entry: Hide two syscall entry assertions behind CONFIG_DEBUG_ENTRY
This shaves a few cycles off the slow paths.
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/ce383fa9e129286ce6da6e00b53acd4c9fb5d06a.1444091585.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/entry/common.c')
| -rw-r--r-- | arch/x86/entry/common.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 08a945d7915e..778ca70c22dd 100644 --- a/arch/x86/entry/common.c +++ b/arch/x86/entry/common.c @@ -71,7 +71,8 @@ unsigned long syscall_trace_enter_phase1(struct pt_regs *regs, u32 arch) unsigned long ret = 0; u32 work; - BUG_ON(regs != task_pt_regs(current)); + if (IS_ENABLED(CONFIG_DEBUG_ENTRY)) + BUG_ON(regs != task_pt_regs(current)); work = ACCESS_ONCE(current_thread_info()->flags) & _TIF_WORK_SYSCALL_ENTRY; @@ -160,7 +161,8 @@ long syscall_trace_enter_phase2(struct pt_regs *regs, u32 arch, u32 work = ACCESS_ONCE(current_thread_info()->flags) & _TIF_WORK_SYSCALL_ENTRY; - BUG_ON(regs != task_pt_regs(current)); + if (IS_ENABLED(CONFIG_DEBUG_ENTRY)) + BUG_ON(regs != task_pt_regs(current)); /* * If we stepped into a sysenter/syscall insn, it trapped in |