Author: jhibbits Date: Fri Nov 15 04:33:07 2019 New Revision: 354723 URL: https://svnweb.freebsd.org/changeset/base/354723
Log: atomic: Add atomic_cmpset_masked to powerpc and use it Summary: This is a more optimal way of doing atomic_compset_masked() than the fallback in sys/_atomic_subword.h. There's also an override for _atomic_fcmpset_masked_word(), which may or may not be necessary, and is unused for powerpc. Reviewed by: kevans, kib Differential Revision: https://reviews.freebsd.org/D22359 Modified: head/sys/powerpc/include/atomic.h head/sys/sys/_atomic_subword.h Modified: head/sys/powerpc/include/atomic.h ============================================================================== --- head/sys/powerpc/include/atomic.h Fri Nov 15 03:40:02 2019 (r354722) +++ head/sys/powerpc/include/atomic.h Fri Nov 15 04:33:07 2019 (r354723) @@ -608,6 +608,38 @@ atomic_cmpset_short(volatile u_short *p, u_short cmpva return (ret); } +#else +static __inline int +atomic_cmpset_masked(uint32_t *p, uint32_t cmpval, uint32_t newval, + uint32_t mask) +{ + int ret; + uint32_t tmp; + + __asm __volatile ( + "1:\tlwarx %2, 0, %2\n\t" /* load old value */ + "and %0, %2, %7\n\t" + "cmplw %4, %0\n\t" /* compare */ + "bne- 2f\n\t" /* exit if not equal */ + "andc %2, %2, %7\n\t" + "or %2, %2, %5\n\t" + "stwcx. %2, 0, %3\n\t" /* attempt to store */ + "bne- 1b\n\t" /* spin if failed */ + "li %0, 1\n\t" /* success - retval = 1 */ + "b 3f\n\t" /* we've succeeded */ + "2:\n\t" + "stwcx. %2, 0, %3\n\t" /* clear reservation (74xx) */ + "li %0, 0\n\t" /* failure - retval = 0 */ + "3:\n\t" + : "=&r" (ret), "=m" (*p), "+&r" (tmp) + : "r" (p), "r" (cmpval), "r" (newval), "m" (*p), + "r" (mask) + : "cr0", "memory"); + + return (ret); +} + +#define _atomic_cmpset_masked_word(a,o,v,m) atomic_cmpset_masked(a, o, v, m) #endif static __inline int Modified: head/sys/sys/_atomic_subword.h ============================================================================== --- head/sys/sys/_atomic_subword.h Fri Nov 15 03:40:02 2019 (r354722) +++ head/sys/sys/_atomic_subword.h Fri Nov 15 04:33:07 2019 (r354723) @@ -63,6 +63,7 @@ ((((__uintptr_t)(p) % 4)) * NBBY) #endif +#ifndef _atomic_cmpset_masked_word /* * Pass these bad boys a couple words and a mask of the bits you care about, * they'll loop until we either succeed or fail because of those bits rather @@ -92,7 +93,9 @@ _atomic_cmpset_masked_word(uint32_t *addr, uint32_t ol return (ret); } +#endif +#ifndef _atomic_fcmpset_masked_word static __inline int _atomic_fcmpset_masked_word(uint32_t *addr, uint32_t *old, uint32_t val, uint32_t mask) @@ -108,6 +111,7 @@ _atomic_fcmpset_masked_word(uint32_t *addr, uint32_t * *old = (*addr & ~mask) | *old; return (atomic_fcmpset_32(addr, old, (*old & ~mask) | val)); } +#endif static __inline int atomic_cmpset_8(__volatile uint8_t *addr, uint8_t old, uint8_t val) _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
