From 7ca2b49b06a6d26e89e3535653889f1d7892b085 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 26 Sep 2006 10:52:32 +0200 Subject: [PATCH] [PATCH] i386: Remove lock section support in semaphore.h Lock sections don't work the new dwarf2 unwinder This generates slightly smaller code. It adds one more taken jump to the fast path. Cc: jbeulich@novell.com Signed-off-by: Andi Kleen --- include/asm-i386/semaphore.h | 49 +++++++++++++----------------------- 1 file changed, 17 insertions(+), 32 deletions(-) diff --git a/include/asm-i386/semaphore.h b/include/asm-i386/semaphore.h index d51e800acf29..e63b6a68f04c 100644 --- a/include/asm-i386/semaphore.h +++ b/include/asm-i386/semaphore.h @@ -100,13 +100,10 @@ static inline void down(struct semaphore * sem) __asm__ __volatile__( "# atomic down operation\n\t" LOCK_PREFIX "decl %0\n\t" /* --sem->count */ - "js 2f\n" - "1:\n" - LOCK_SECTION_START("") - "2:\tlea %0,%%eax\n\t" - "call __down_failed\n\t" - "jmp 1b\n" - LOCK_SECTION_END + "jns 2f\n" + "\tlea %0,%%eax\n\t" + "call __down_failed\n" + "2:" :"+m" (sem->count) : :"memory","ax"); @@ -123,15 +120,12 @@ static inline int down_interruptible(struct semaphore * sem) might_sleep(); __asm__ __volatile__( "# atomic interruptible down operation\n\t" + "xorl %0,%0\n\t" LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "js 2f\n\t" - "xorl %0,%0\n" - "1:\n" - LOCK_SECTION_START("") - "2:\tlea %1,%%eax\n\t" - "call __down_failed_interruptible\n\t" - "jmp 1b\n" - LOCK_SECTION_END + "jns 2f\n\t" + "lea %1,%%eax\n\t" + "call __down_failed_interruptible\n" + "2:" :"=a" (result), "+m" (sem->count) : :"memory"); @@ -148,15 +142,12 @@ static inline int down_trylock(struct semaphore * sem) __asm__ __volatile__( "# atomic interruptible down operation\n\t" + "xorl %0,%0\n\t" LOCK_PREFIX "decl %1\n\t" /* --sem->count */ - "js 2f\n\t" - "xorl %0,%0\n" - "1:\n" - LOCK_SECTION_START("") - "2:\tlea %1,%%eax\n\t" + "jns 2f\n\t" + "lea %1,%%eax\n\t" "call __down_failed_trylock\n\t" - "jmp 1b\n" - LOCK_SECTION_END + "2:\n" :"=a" (result), "+m" (sem->count) : :"memory"); @@ -166,22 +157,16 @@ static inline int down_trylock(struct semaphore * sem) /* * Note! This is subtle. We jump to wake people up only if * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). */ static inline void up(struct semaphore * sem) { __asm__ __volatile__( "# atomic up operation\n\t" LOCK_PREFIX "incl %0\n\t" /* ++sem->count */ - "jle 2f\n" - "1:\n" - LOCK_SECTION_START("") - "2:\tlea %0,%%eax\n\t" - "call __up_wakeup\n\t" - "jmp 1b\n" - LOCK_SECTION_END - ".subsection 0\n" + "jg 1f\n\t" + "lea %0,%%eax\n\t" + "call __up_wakeup\n" + "1:" :"+m" (sem->count) : :"memory","ax"); -- 2.20.1