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Fix umtxq_sleep() regression caused by 56070dd2e4.

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umtxq_requeue() moves the queue to a different hash chain and different
lock, so we can't rely on msleep_sbt() reacquiring the same old lock.
We have to use PDROP and update the queue chain and so lock pointer.

PR:		262587
MFC after:	2 weeks
This commit is contained in:
Alexander Motin 2022-03-21 19:43:39 -04:00
parent 27f56d337b
commit fd6ca665d2
1 changed files with 3 additions and 1 deletions
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4
sys/kern/kern_umtx.c
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@ -808,8 +808,10 @@ umtxq_sleep(struct umtx_q *uq, const char *wmesg,
if (error != 0)
break;
}
error = msleep_sbt(uq, &uc->uc_lock, PCATCH, wmesg,
error = msleep_sbt(uq, &uc->uc_lock, PCATCH | PDROP, wmesg,
sbt, 0, flags);
uc = umtxq_getchain(&uq->uq_key);
mtx_lock(&uc->uc_lock);
if (error == EINTR || error == ERESTART)
break;
if (error == EWOULDBLOCK && (flags & C_ABSOLUTE) != 0) {