diff options
Diffstat (limited to 'kernel/srcu.c')
| -rw-r--r-- | kernel/srcu.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/kernel/srcu.c b/kernel/srcu.c index 7cf5bab..f098f17 100644 --- a/kernel/srcu.c +++ b/kernel/srcu.c @@ -450,10 +450,12 @@ static void __synchronize_srcu(struct srcu_struct *sp, int trycount) * synchronize_srcu - wait for prior SRCU read-side critical-section completion * @sp: srcu_struct with which to synchronize. * - * Flip the completed counter, and wait for the old count to drain to zero. - * As with classic RCU, the updater must use some separate means of - * synchronizing concurrent updates. Can block; must be called from - * process context. + * Wait for the count to drain to zero of both indexes. To avoid the + * possible starvation of synchronize_srcu(), it waits for the count of + * the index=((->completed & 1) ^ 1) to drain to zero at first, + * and then flip the completed and wait for the count of the other index. + * + * Can block; must be called from process context. * * Note that it is illegal to call synchronize_srcu() from the corresponding * SRCU read-side critical section; doing so will result in deadlock. |
