diff options
| author | Dmitry Eremin-Solenikov <dmitry.ereminsolenikov@linaro.org> | 2017-05-05 01:00:08 +0300 |
|---|---|---|
| committer | Maxim Uvarov <maxim.uvarov@linaro.org> | 2017-05-12 01:27:29 +0300 |
| commit | 86e5b478325a0f5422fc6edff9db168d44852d2e (patch) | |
| tree | 3fc87b349500574b5c30df1296878a4f6721951c /platform/linux-generic | |
| parent | c1e962548f5082554bb52137765a258b3a29283c (diff) | |
linux-generic: rwlock: fix odp_rwlock_read_trylock()
odp_rwlock_read_trylock() currently works only if there are no readers
(and writers) as it compares counter with 0. Make it actually work in
case there are other active readers.
Fixes: https://bugs.linaro.org/show_bug.cgi?id=2974
Signed-off-by: Dmitry Eremin-Solenikov <dmitry.ereminsolenikov@linaro.org>
Reviewed-by: Bill Fischofer <bill.fischofer@linaro.org>
Signed-off-by: Maxim Uvarov <maxim.uvarov@linaro.org>
Diffstat (limited to 'platform/linux-generic')
| -rw-r--r-- | platform/linux-generic/odp_rwlock.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/platform/linux-generic/odp_rwlock.c b/platform/linux-generic/odp_rwlock.c index 13c17a2c7..5bef13a45 100644 --- a/platform/linux-generic/odp_rwlock.c +++ b/platform/linux-generic/odp_rwlock.c @@ -33,9 +33,14 @@ void odp_rwlock_read_lock(odp_rwlock_t *rwlock) int odp_rwlock_read_trylock(odp_rwlock_t *rwlock) { - uint32_t zero = 0; + uint32_t cnt = odp_atomic_load_u32(&rwlock->cnt); + + while (cnt != (uint32_t)-1) { + if (odp_atomic_cas_acq_u32(&rwlock->cnt, &cnt, cnt + 1)) + return 1; + } - return odp_atomic_cas_acq_u32(&rwlock->cnt, &zero, (uint32_t)1); + return 0; } void odp_rwlock_read_unlock(odp_rwlock_t *rwlock) |