Commit 8e35ac73 authored by Guo Ren's avatar Guo Ren
Browse files

csky: Cleanup asm/spinlock.h 

There are two implementation of spinlock in arch/csky:
 - simple one (NR_CPU = 1,2)
 - tick's one (NR_CPU = 3,4)
Remove the simple one.

There is already smp_mb in spinlock, so remove the definition of
smp_mb__after_spinlock.

Link: https://lore.kernel.org/linux-csky/20200807081253.GD2674@hirez.programming.kicks-ass.net/#t


Signed-off-by: default avatarGuo Ren <guoren@linux.alibaba.com>
Cc: Peter Zijlstra <peterz@infradead.org>k
Cc: Arnd Bergmann <arnd@arndb.de>
parent c38425df

arch/csky/Kconfig

+1 −1
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ config CSKY 
	select ARCH_HAS_SYNC_DMA_FOR_CPU

	select ARCH_HAS_SYNC_DMA_FOR_DEVICE

	select ARCH_USE_BUILTIN_BSWAP

	select ARCH_USE_QUEUED_RWLOCKS if NR_CPUS>2

	select ARCH_USE_QUEUED_RWLOCKS

	select ARCH_WANT_FRAME_POINTERS if !CPU_CK610

	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT

	select COMMON_CLK

arch/csky/include/asm/spinlock.h

+0 −167
Original line number Diff line number Diff line
@@ -6,8 +6,6 @@ 
#include <linux/spinlock_types.h>

#include <asm/barrier.h>



#ifdef CONFIG_QUEUED_RWLOCKS



/*

 * Ticket-based spin-locking.

 */
@@ -88,169 +86,4 @@ static inline int arch_spin_is_contended(arch_spinlock_t *lock) 


#include <asm/qrwlock.h>



/* See include/linux/spinlock.h */

#define smp_mb__after_spinlock()	smp_mb()



#else /* CONFIG_QUEUED_RWLOCKS */



/*

 * Test-and-set spin-locking.

 */

static inline void arch_spin_lock(arch_spinlock_t *lock)

{

	u32 *p = &lock->lock;

	u32 tmp;



	asm volatile (

		"1:	ldex.w		%0, (%1) \n"

		"	bnez		%0, 1b   \n"

		"	movi		%0, 1    \n"

		"	stex.w		%0, (%1) \n"

		"	bez		%0, 1b   \n"

		: "=&r" (tmp)

		: "r"(p)

		: "cc");

	smp_mb();

}



static inline void arch_spin_unlock(arch_spinlock_t *lock)

{

	smp_mb();

	WRITE_ONCE(lock->lock, 0);

}



static inline int arch_spin_trylock(arch_spinlock_t *lock)

{

	u32 *p = &lock->lock;

	u32 tmp;



	asm volatile (

		"1:	ldex.w		%0, (%1) \n"

		"	bnez		%0, 2f   \n"

		"	movi		%0, 1    \n"

		"	stex.w		%0, (%1) \n"

		"	bez		%0, 1b   \n"

		"	movi		%0, 0    \n"

		"2:				 \n"

		: "=&r" (tmp)

		: "r"(p)

		: "cc");



	if (!tmp)

		smp_mb();



	return !tmp;

}



#define arch_spin_is_locked(x)	(READ_ONCE((x)->lock) != 0)



/*

 * read lock/unlock/trylock

 */

static inline void arch_read_lock(arch_rwlock_t *lock)

{

	u32 *p = &lock->lock;

	u32 tmp;



	asm volatile (

		"1:	ldex.w		%0, (%1) \n"

		"	blz		%0, 1b   \n"

		"	addi		%0, 1    \n"

		"	stex.w		%0, (%1) \n"

		"	bez		%0, 1b   \n"

		: "=&r" (tmp)

		: "r"(p)

		: "cc");

	smp_mb();

}



static inline void arch_read_unlock(arch_rwlock_t *lock)

{

	u32 *p = &lock->lock;

	u32 tmp;



	smp_mb();

	asm volatile (

		"1:	ldex.w		%0, (%1) \n"

		"	subi		%0, 1    \n"

		"	stex.w		%0, (%1) \n"

		"	bez		%0, 1b   \n"

		: "=&r" (tmp)

		: "r"(p)

		: "cc");

}



static inline int arch_read_trylock(arch_rwlock_t *lock)

{

	u32 *p = &lock->lock;

	u32 tmp;



	asm volatile (

		"1:	ldex.w		%0, (%1) \n"

		"	blz		%0, 2f   \n"

		"	addi		%0, 1    \n"

		"	stex.w		%0, (%1) \n"

		"	bez		%0, 1b   \n"

		"	movi		%0, 0    \n"

		"2:				 \n"

		: "=&r" (tmp)

		: "r"(p)

		: "cc");



	if (!tmp)

		smp_mb();



	return !tmp;

}



/*

 * write lock/unlock/trylock

 */

static inline void arch_write_lock(arch_rwlock_t *lock)

{

	u32 *p = &lock->lock;

	u32 tmp;



	asm volatile (

		"1:	ldex.w		%0, (%1) \n"

		"	bnez		%0, 1b   \n"

		"	subi		%0, 1    \n"

		"	stex.w		%0, (%1) \n"

		"	bez		%0, 1b   \n"

		: "=&r" (tmp)

		: "r"(p)

		: "cc");

	smp_mb();

}



static inline void arch_write_unlock(arch_rwlock_t *lock)

{

	smp_mb();

	WRITE_ONCE(lock->lock, 0);

}



static inline int arch_write_trylock(arch_rwlock_t *lock)

{

	u32 *p = &lock->lock;

	u32 tmp;



	asm volatile (

		"1:	ldex.w		%0, (%1) \n"

		"	bnez		%0, 2f   \n"

		"	subi		%0, 1    \n"

		"	stex.w		%0, (%1) \n"

		"	bez		%0, 1b   \n"

		"	movi		%0, 0    \n"

		"2:				 \n"

		: "=&r" (tmp)

		: "r"(p)

		: "cc");



	if (!tmp)

		smp_mb();



	return !tmp;

}



#endif /* CONFIG_QUEUED_RWLOCKS */

#endif /* __ASM_CSKY_SPINLOCK_H */

arch/csky/include/asm/spinlock_types.h

+0 −10
Original line number Diff line number Diff line
@@ -22,16 +22,6 @@ typedef struct { 


#define __ARCH_SPIN_LOCK_UNLOCKED	{ { 0 } }



#ifdef CONFIG_QUEUED_RWLOCKS

#include <asm-generic/qrwlock_types.h>



#else /* CONFIG_NR_CPUS > 2 */



typedef struct {

	u32 lock;

} arch_rwlock_t;



#define __ARCH_RW_LOCK_UNLOCKED		{ 0 }



#endif /* CONFIG_QUEUED_RWLOCKS */

#endif /* __ASM_CSKY_SPINLOCK_TYPES_H */