diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-07-26 12:14:46 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-07-26 12:14:46 -0700 |
commit | 40c60ac32174f0c0c090cd31d0d1712f2478e689 (patch) | |
tree | 082e765c485880d42e64f3c4aa0c6e637beb269e /arch | |
parent | 1ada9010e578150984039a770c98f41799b30bc4 (diff) | |
parent | be6577af0cef934ccb036445314072e8cb9217b9 (diff) | |
download | lwn-40c60ac32174f0c0c090cd31d0d1712f2478e689.tar.gz lwn-40c60ac32174f0c0c090cd31d0d1712f2478e689.zip |
Merge branch 'parisc-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux into master
Pull parisc fixes from Helge Deller:
"Two fixes:
- Add the cmpxchg() function for pointers to u8 values. This fixes a
kernel linking error when building the tusb1210 driver (from Liam
Beguin).
- Add a define for atomic64_set_release() to fix CPU soft lockups
which happen because of missing unlocks while processing bit
operations (from John David Anglin)"
* 'parisc-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Add atomic64_set_release() define to avoid CPU soft lockups
parisc: add support for cmpxchg on u8 pointers
Diffstat (limited to 'arch')
-rw-r--r-- | arch/parisc/include/asm/atomic.h | 2 | ||||
-rw-r--r-- | arch/parisc/include/asm/cmpxchg.h | 2 | ||||
-rw-r--r-- | arch/parisc/lib/bitops.c | 12 |
3 files changed, 16 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/atomic.h b/arch/parisc/include/asm/atomic.h index 118953d41763..6dd4171c9530 100644 --- a/arch/parisc/include/asm/atomic.h +++ b/arch/parisc/include/asm/atomic.h @@ -212,6 +212,8 @@ atomic64_set(atomic64_t *v, s64 i) _atomic_spin_unlock_irqrestore(v, flags); } +#define atomic64_set_release(v, i) atomic64_set((v), (i)) + static __inline__ s64 atomic64_read(const atomic64_t *v) { diff --git a/arch/parisc/include/asm/cmpxchg.h b/arch/parisc/include/asm/cmpxchg.h index ab5c215cf46c..068958575871 100644 --- a/arch/parisc/include/asm/cmpxchg.h +++ b/arch/parisc/include/asm/cmpxchg.h @@ -60,6 +60,7 @@ extern void __cmpxchg_called_with_bad_pointer(void); extern unsigned long __cmpxchg_u32(volatile unsigned int *m, unsigned int old, unsigned int new_); extern u64 __cmpxchg_u64(volatile u64 *ptr, u64 old, u64 new_); +extern u8 __cmpxchg_u8(volatile u8 *ptr, u8 old, u8 new_); /* don't worry...optimizer will get rid of most of this */ static inline unsigned long @@ -71,6 +72,7 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new_, int size) #endif case 4: return __cmpxchg_u32((unsigned int *)ptr, (unsigned int)old, (unsigned int)new_); + case 1: return __cmpxchg_u8((u8 *)ptr, (u8)old, (u8)new_); } __cmpxchg_called_with_bad_pointer(); return old; diff --git a/arch/parisc/lib/bitops.c b/arch/parisc/lib/bitops.c index 70ffbcf889b8..2e4d1f05a926 100644 --- a/arch/parisc/lib/bitops.c +++ b/arch/parisc/lib/bitops.c @@ -79,3 +79,15 @@ unsigned long __cmpxchg_u32(volatile unsigned int *ptr, unsigned int old, unsign _atomic_spin_unlock_irqrestore(ptr, flags); return (unsigned long)prev; } + +u8 __cmpxchg_u8(volatile u8 *ptr, u8 old, u8 new) +{ + unsigned long flags; + u8 prev; + + _atomic_spin_lock_irqsave(ptr, flags); + if ((prev = *ptr) == old) + *ptr = new; + _atomic_spin_unlock_irqrestore(ptr, flags); + return prev; +} |