On Wed, Feb 01, 2017 at 05:00:34AM +0000, Alexander Kabaev wrote: > Author: kan > Date: Wed Feb 1 05:00:34 2017 > New Revision: 313040 > URL: https://svnweb.freebsd.org/changeset/base/313040 > > Log: > Add atomic_fcmpset_*() inlines for MIPS > > atomic_fcmpset_*() is analogous to atomic_cmpset(), but saves off the > read value from the target memory location into the 'old' pointer. > > Reviewed by: imp, brooks > Requested by: mjg > Differential Revision: https://reviews.freebsd.org/D9391 > > Modified: > head/sys/mips/include/atomic.h > > Modified: head/sys/mips/include/atomic.h > ============================================================================== > --- head/sys/mips/include/atomic.h Wed Feb 1 04:54:23 2017 > (r313039) > +++ head/sys/mips/include/atomic.h Wed Feb 1 05:00:34 2017 > (r313040) > @@ -362,7 +362,7 @@ atomic_load_64(__volatile uint64_t *p, u > * zero if the compare failed, nonzero otherwise. > */ > static __inline uint32_t > -atomic_cmpset_32(__volatile uint32_t* p, uint32_t cmpval, uint32_t newval) > +atomic_cmpset_32(__volatile uint32_t *p, uint32_t cmpval, uint32_t newval) > { > uint32_t ret; > > @@ -405,6 +405,46 @@ atomic_cmpset_rel_32(__volatile uint32_t > return (atomic_cmpset_32(p, cmpval, newval)); > } > > +static __inline uint32_t > +atomic_fcmpset_32(__volatile uint32_t *p, uint32_t *cmpval, uint32_t newval) > +{ > + uint32_t ret; > + > + __asm __volatile ( > + "1:\n\t" > + "ll %0, %1\n\t" /* load old value */ > + "bne %0, %4, 2f\n\t" /* compare */ > + "move %0, %3\n\t" /* value to store */ > + "sc %0, %1\n\t" /* attempt to store */ > + "beqz %0, 1b\n\t" /* if it failed, spin */ Please do not retry on sc failure, return the error to upper layer. See also r313007 and preceeding discussion after r312973.
> + "j 3f\n\t" > + "2:\n\t" > + "sw %0, %2\n\t" /* save old value */ > + "li %0, 0\n\t" > + "3:\n" > + : "=&r" (ret), "+m" (*p), "=m" (*cmpval) > + : "r" (newval), "r" (*cmpval) > + : "memory"); > + return ret; > +} > + _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
