diff options
| author | Visa Hankala <visa@cvs.openbsd.org> | 2020-01-10 15:49:38 +0000 |
|---|---|---|
| committer | Visa Hankala <visa@cvs.openbsd.org> | 2020-01-10 15:49:38 +0000 |
| commit | 57a998ced48546d8e1a0d0216fbccffd28ab5d8a (patch) | |
| tree | b2c66e14b31d23a6a381cecbd892bac911e1e04f /sys/kern | |
| parent | 8af6e4bffe18041d6d57a19e86e13b562675f731 (diff) | |
Use atomic operations with kq_refs, to nudge the code toward MP-safety.
While here, adjust the IPL of kqueue-related pools to IPL_MPFLOOR.
OK bluhm@, anton@, mpi@
Diffstat (limited to 'sys/kern')
| -rw-r--r-- | sys/kern/kern_event.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/sys/kern/kern_event.c b/sys/kern/kern_event.c index fac5aa1ab83..f0224b6ea2b 100644 --- a/sys/kern/kern_event.c +++ b/sys/kern/kern_event.c @@ -1,4 +1,4 @@ -/* $OpenBSD: kern_event.c,v 1.118 2020/01/08 16:45:28 visa Exp $ */ +/* $OpenBSD: kern_event.c,v 1.119 2020/01/10 15:49:37 visa Exp $ */ /*- * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org> @@ -30,6 +30,7 @@ #include <sys/param.h> #include <sys/systm.h> +#include <sys/atomic.h> #include <sys/kernel.h> #include <sys/proc.h> #include <sys/pledge.h> @@ -156,17 +157,18 @@ void KQRELE(struct kqueue *); void KQREF(struct kqueue *kq) { - ++kq->kq_refs; + atomic_inc_int(&kq->kq_refs); } void KQRELE(struct kqueue *kq) { - struct filedesc *fdp = kq->kq_fdp; + struct filedesc *fdp; - if (--kq->kq_refs > 0) + if (atomic_dec_int_nv(&kq->kq_refs) > 0) return; + fdp = kq->kq_fdp; if (rw_status(&fdp->fd_lock) == RW_WRITE) { LIST_REMOVE(kq, kq_next); } else { @@ -185,11 +187,10 @@ void kqueue_init(void); void kqueue_init(void) { - - pool_init(&kqueue_pool, sizeof(struct kqueue), 0, IPL_NONE, PR_WAITOK, - "kqueuepl", NULL); - pool_init(&knote_pool, sizeof(struct knote), 0, IPL_NONE, PR_WAITOK, - "knotepl", NULL); + pool_init(&kqueue_pool, sizeof(struct kqueue), 0, IPL_MPFLOOR, + PR_WAITOK, "kqueuepl", NULL); + pool_init(&knote_pool, sizeof(struct knote), 0, IPL_MPFLOOR, + PR_WAITOK, "knotepl", NULL); } int @@ -480,11 +481,11 @@ sys_kqueue(struct proc *p, void *v, register_t *retval) fp->f_type = DTYPE_KQUEUE; fp->f_ops = &kqueueops; kq = pool_get(&kqueue_pool, PR_WAITOK|PR_ZERO); + kq->kq_refs = 1; + kq->kq_fdp = fdp; TAILQ_INIT(&kq->kq_head); fp->f_data = kq; - KQREF(kq); *retval = fd; - kq->kq_fdp = fdp; LIST_INSERT_HEAD(&fdp->fd_kqlist, kq, kq_next); fdinsert(fdp, fd, 0, fp); FRELE(fp, p); |