BackPup/Linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-15 15:01:08 -04:00
Code Issues Packages Projects Releases Wiki Activity

[PATCH] Directed yield: direct yield of spinlocks for s390.

Browse Source 
Use the new diagnose 0x9c in the spinlock implementation for s390.  It
yields the remaining timeslice of the virtual cpu that tries to acquire a
lock to the virtual cpu that is the current holder of the lock.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Martin Schwidefsky
2006-09-30 23:27:45 -07:00
committed by Linus Torvalds
parent cdc39363d3
commit 3c1fcfe229
6 changed files with 87 additions and 35 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
include/asm-s390/setup.h
View File

@@ -39,6 +39,7 @@ extern unsigned long machine_flags;
#define MACHINE_IS_P390 (machine_flags & 4)
#define MACHINE_HAS_MVPG (machine_flags & 16)
#define MACHINE_HAS_IDTE (machine_flags & 128)
#define MACHINE_HAS_DIAG9C (machine_flags & 256)
#ifndef __s390x__
#define MACHINE_HAS_IEEE (machine_flags & 2)

31
include/asm-s390/spinlock.h
View File

@@ -13,6 +13,8 @@
#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
#include <linux/smp.h>
static inline int
_raw_compare_and_swap(volatile unsigned int *lock,
unsigned int old, unsigned int new)
@@ -50,34 +52,46 @@ _raw_compare_and_swap(volatile unsigned int *lock,
* (the type definitions are in asm/spinlock_types.h)
*/
#define __raw_spin_is_locked(x) ((x)->lock != 0)
#define __raw_spin_is_locked(x) ((x)->owner_cpu != 0)
#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
#define __raw_spin_unlock_wait(lock) \
do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0)
do { while (__raw_spin_is_locked(lock)) \
_raw_spin_relax(lock); } while (0)
extern void _raw_spin_lock_wait(raw_spinlock_t *lp, unsigned int pc);
extern int _raw_spin_trylock_retry(raw_spinlock_t *lp, unsigned int pc);
extern void _raw_spin_lock_wait(raw_spinlock_t *, unsigned int pc);
extern int _raw_spin_trylock_retry(raw_spinlock_t *, unsigned int pc);
extern void _raw_spin_relax(raw_spinlock_t *lock);
static inline void __raw_spin_lock(raw_spinlock_t *lp)
{
unsigned long pc = 1 | (unsigned long) __builtin_return_address(0);
int old;
if (unlikely(_raw_compare_and_swap(&lp->lock, 0, pc) != 0))
_raw_spin_lock_wait(lp, pc);
old = _raw_compare_and_swap(&lp->owner_cpu, 0, ~smp_processor_id());
if (likely(old == 0)) {
lp->owner_pc = pc;
return;
}
_raw_spin_lock_wait(lp, pc);
}
static inline int __raw_spin_trylock(raw_spinlock_t *lp)
{
unsigned long pc = 1 | (unsigned long) __builtin_return_address(0);
int old;
if (likely(_raw_compare_and_swap(&lp->lock, 0, pc) == 0))
old = _raw_compare_and_swap(&lp->owner_cpu, 0, ~smp_processor_id());
if (likely(old == 0)) {
lp->owner_pc = pc;
return 1;
}
return _raw_spin_trylock_retry(lp, pc);
}
static inline void __raw_spin_unlock(raw_spinlock_t *lp)
{
_raw_compare_and_swap(&lp->lock, lp->lock, 0);
lp->owner_pc = 0;
_raw_compare_and_swap(&lp->owner_cpu, lp->owner_cpu, 0);
}
/*
@@ -154,7 +168,6 @@ static inline int __raw_write_trylock(raw_rwlock_t *rw)
return _raw_write_trylock_retry(rw);
}
#define _raw_spin_relax(lock) cpu_relax()
#define _raw_read_relax(lock) cpu_relax()
#define _raw_write_relax(lock) cpu_relax()

6
include/asm-s390/spinlock_types.h
View File

@@ -6,16 +6,16 @@
#endif
typedef struct {
volatile unsigned int lock;
volatile unsigned int owner_cpu;
volatile unsigned int owner_pc;
} __attribute__ ((aligned (4))) raw_spinlock_t;
#define __RAW_SPIN_LOCK_UNLOCKED { 0 }
typedef struct {
volatile unsigned int lock;
volatile unsigned int owner_pc;
} raw_rwlock_t;
#define __RAW_RW_LOCK_UNLOCKED { 0, 0 }
#define __RAW_RW_LOCK_UNLOCKED { 0 }
#endif