Commit-ID: 4aabd140f9cbe0361401a1368bac74df1010abf5 Gitweb: http://git.kernel.org/tip/4aabd140f9cbe0361401a1368bac74df1010abf5 Author: Andy Lutomirski <luto@xxxxxxxxxx> AuthorDate: Mon, 5 Oct 2015 17:48:21 -0700 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Fri, 9 Oct 2015 09:41:12 +0200 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@xxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Brian Gerst <brgerst@xxxxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: linux-kernel@xxxxxxxxxxxxxxx Link: http://lkml.kernel.org/r/ce383fa9e129286ce6da6e00b53acd4c9fb5d06a.1444091585.git.luto@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/entry/common.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c index 08a945d..778ca70 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 -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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