Merge branch 'parisc-4.20-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

Pull parisc fix from Helge Deller:
 "Revert one patch which changed how spinlocks get released. It breaks
  the rwlock implementation in glibc"

* 'parisc-4.20-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Revert "Release spinlocks using ordered store"
This commit is contained in:
Linus Torvalds 2018-11-14 13:42:41 -06:00
commit 857c34cd09
2 changed files with 10 additions and 6 deletions

View File

@ -37,8 +37,8 @@ static inline void arch_spin_unlock(arch_spinlock_t *x)
volatile unsigned int *a;
a = __ldcw_align(x);
/* Release with ordered store. */
__asm__ __volatile__("stw,ma %0,0(%1)" : : "r"(1), "r"(a) : "memory");
mb();
*a = 1;
}
static inline int arch_spin_trylock(arch_spinlock_t *x)

View File

@ -640,7 +640,8 @@ cas_action:
sub,<> %r28, %r25, %r0
2: stw %r24, 0(%r26)
/* Free lock */
stw,ma %r20, 0(%sr2,%r20)
sync
stw %r20, 0(%sr2,%r20)
#if ENABLE_LWS_DEBUG
/* Clear thread register indicator */
stw %r0, 4(%sr2,%r20)
@ -654,7 +655,8 @@ cas_action:
3:
/* Error occurred on load or store */
/* Free lock */
stw,ma %r20, 0(%sr2,%r20)
sync
stw %r20, 0(%sr2,%r20)
#if ENABLE_LWS_DEBUG
stw %r0, 4(%sr2,%r20)
#endif
@ -855,7 +857,8 @@ cas2_action:
cas2_end:
/* Free lock */
stw,ma %r20, 0(%sr2,%r20)
sync
stw %r20, 0(%sr2,%r20)
/* Enable interrupts */
ssm PSW_SM_I, %r0
/* Return to userspace, set no error */
@ -865,7 +868,8 @@ cas2_end:
22:
/* Error occurred on load or store */
/* Free lock */
stw,ma %r20, 0(%sr2,%r20)
sync
stw %r20, 0(%sr2,%r20)
ssm PSW_SM_I, %r0
ldo 1(%r0),%r28
b lws_exit