Re: [PATCH rtems-libbsd 2/2] rtemsbsd/atomic: Return a value for CMPSET
OK On 8/10/21 7:43 am, Kinsey Moore wrote: > When the cmpset and fcmpset functions were refactored, the return value > of the operation was discarded instead of being returned for SMP builds > outside of gcc 4.x. This had the effect of turning these functions into > a long busywait loop that eventually failed due to integer overflow. > > This patch restores the use of the return value of the atomic > operations. > --- > rtemsbsd/include/machine/atomic.h | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/rtemsbsd/include/machine/atomic.h > b/rtemsbsd/include/machine/atomic.h > index 9465fefd..f25dc5d0 100644 > --- a/rtemsbsd/include/machine/atomic.h > +++ b/rtemsbsd/include/machine/atomic.h > @@ -530,7 +530,7 @@ atomic_clear_rel_long(volatile long *p, long v) > #elif defined(_RTEMS_BSD_MACHINE_ATOMIC_USE_STDATOMIC) > #define _ATOMIC_CMPSET(T, p, cmp, set, mo) \ > atomic_##T *q = (atomic_##T *)RTEMS_DEVOLATILE(T *, p); \ > - atomic_compare_exchange_strong_explicit(q, , set, \ > + rv = atomic_compare_exchange_strong_explicit(q, , set, \ > mo, memory_order_relaxed) > #else > #define _ATOMIC_CMPSET(T, p, cmp, set, mo) \ > @@ -676,7 +676,7 @@ atomic_cmpset_rel_ptr(volatile uintptr_t *p, uintptr_t > cmp, uintptr_t set) > #elif defined(_RTEMS_BSD_MACHINE_ATOMIC_USE_STDATOMIC) > #define _ATOMIC_FCMPSET(T, p, cmp, set, mo) \ > atomic_##T *q = (atomic_##T *)RTEMS_DEVOLATILE(T *, p); \ > - atomic_compare_exchange_strong_explicit(q, cmp, set, \ > + rv = atomic_compare_exchange_strong_explicit(q, cmp, set, \ > mo, memory_order_relaxed) > #else > #define _ATOMIC_FCMPSET(T, p, cmp, set, mo) \ > ___ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
[PATCH rtems-libbsd 2/2] rtemsbsd/atomic: Return a value for CMPSET
When the cmpset and fcmpset functions were refactored, the return value of the operation was discarded instead of being returned for SMP builds outside of gcc 4.x. This had the effect of turning these functions into a long busywait loop that eventually failed due to integer overflow. This patch restores the use of the return value of the atomic operations. --- rtemsbsd/include/machine/atomic.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/rtemsbsd/include/machine/atomic.h b/rtemsbsd/include/machine/atomic.h index 9465fefd..f25dc5d0 100644 --- a/rtemsbsd/include/machine/atomic.h +++ b/rtemsbsd/include/machine/atomic.h @@ -530,7 +530,7 @@ atomic_clear_rel_long(volatile long *p, long v) #elif defined(_RTEMS_BSD_MACHINE_ATOMIC_USE_STDATOMIC) #define _ATOMIC_CMPSET(T, p, cmp, set, mo) \ atomic_##T *q = (atomic_##T *)RTEMS_DEVOLATILE(T *, p); \ - atomic_compare_exchange_strong_explicit(q, , set, \ + rv = atomic_compare_exchange_strong_explicit(q, , set, \ mo, memory_order_relaxed) #else #define _ATOMIC_CMPSET(T, p, cmp, set, mo) \ @@ -676,7 +676,7 @@ atomic_cmpset_rel_ptr(volatile uintptr_t *p, uintptr_t cmp, uintptr_t set) #elif defined(_RTEMS_BSD_MACHINE_ATOMIC_USE_STDATOMIC) #define _ATOMIC_FCMPSET(T, p, cmp, set, mo) \ atomic_##T *q = (atomic_##T *)RTEMS_DEVOLATILE(T *, p); \ - atomic_compare_exchange_strong_explicit(q, cmp, set, \ + rv = atomic_compare_exchange_strong_explicit(q, cmp, set, \ mo, memory_order_relaxed) #else #define _ATOMIC_FCMPSET(T, p, cmp, set, mo) \ -- 2.30.2 ___ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
