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Add umtxq_lock/unlock around umtx_signal, fix debug kernel compiling,

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let umtx_lock returns EINTR when it returns ERESTART, this lets
userland have chance to back off mtx lock code when needed.
This commit is contained in:
David Xu 2004-12-24 11:59:20 +00:00
parent a08c214a72
commit 3dd213f160
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=139258
1 changed files with 9 additions and 5 deletions
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14
sys/kern/kern_umtx.c
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@ -178,7 +178,7 @@ umtxq_unbusy(struct umtx_key *key)
int chain = umtxq_hash(key);
mtx_assert(umtxq_mtx(chain), MA_OWNED);
KASSERT(umtxq_chains[chain].uc_flags & UCF_BUSY, "not busy");
KASSERT(umtxq_chains[chain].uc_flags & UCF_BUSY, ("not busy"));
umtxq_chains[chain].uc_flags &= ~UCF_BUSY;
if (umtxq_chains[chain].uc_flags & UCF_WANT) {
umtxq_chains[chain].uc_flags &= ~UCF_WANT;
@ -545,13 +545,15 @@ do_lock(struct thread *td, struct umtx *umtx, long id,
}
timo = tvtohz(&tv);
error = _do_lock(td, umtx, id, timo);
if (error != EWOULDBLOCK) {
if (error == ERESTART)
error = EINTR;
if (error != EWOULDBLOCK)
break;
}
}
}
/*
* This lets userland back off critical region if needed.
*/
if (error == ERESTART)
error = EINTR;
return (error);
}
@ -704,7 +706,9 @@ do_wake(struct thread *td, void *uaddr, int n_wake)
if ((ret = umtx_key_get(td, uaddr, &key)) != 0)
return (ret);
umtxq_lock(&key);
ret = umtxq_signal(&key, n_wake);
umtxq_unlock(&key);
umtx_key_release(&key);
td->td_retval[0] = ret;
return (0);