Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7ca2b49b authored by Andi Kleen's avatar Andi Kleen Committed by Andi Kleen
Browse files

[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: default avatarAndi Kleen <ak@suse.de>
parent add659bf

include/asm-i386/semaphore.h

+17 −32
Original line number Diff line number Diff line
@@ -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");