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Groups > linux.kernel > #1240072

[PATCH v2 33/36] x86/entry: Hide two syscall entry assertions behind CONFIG_DEBUG_ENTRY

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This shaves a few cycles off the slow paths.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
 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 3ae6191ad1a2..88966fbf7125 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
-- 
2.4.3

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[PATCH v2 33/36] x86/entry: Hide two syscall entry assertions behind CONFIG_DEBUG_ENTRY Andy Lutomirski <luto@kernel.org> - 2015-10-06 03:00 +0200
  [tip:x86/asm] x86/entry:   Hide two syscall entry assertions behind CONFIG_DEBUG_ENTRY tip-bot for Andy Lutomirski <tipbot@zytor.com> - 2015-10-09 15:20 +0200

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