diff options
Diffstat (limited to 'sys/kern/subr_pool.c')
| -rw-r--r-- | sys/kern/subr_pool.c | 54 |
1 files changed, 52 insertions, 2 deletions
diff --git a/sys/kern/subr_pool.c b/sys/kern/subr_pool.c index d7ffaec5f9f..20eb8714eb7 100644 --- a/sys/kern/subr_pool.c +++ b/sys/kern/subr_pool.c @@ -1,4 +1,4 @@ -/* $OpenBSD: subr_pool.c,v 1.21 2002/01/23 01:44:20 art Exp $ */ +/* $OpenBSD: subr_pool.c,v 1.22 2002/01/25 15:50:22 art Exp $ */ /* $NetBSD: subr_pool.c,v 1.61 2001/09/26 07:14:56 chs Exp $ */ /*- @@ -439,6 +439,8 @@ pool_init(struct pool *pp, size_t size, u_int align, u_int ioff, int flags, pp->pr_hardlimit_ratecap.tv_usec = 0; pp->pr_hardlimit_warning_last.tv_sec = 0; pp->pr_hardlimit_warning_last.tv_usec = 0; + pp->pr_drain_hook = NULL; + pp->pr_drain_hook_arg = NULL; pp->pr_serial = ++pool_serial; if (pool_serial == 0) panic("pool_init: too much uptime"); @@ -577,6 +579,20 @@ pool_destroy(struct pool *pp) #endif } +void +pool_set_drain_hook(struct pool *pp, void (*fn)(void *, int), void *fnarg) +{ + /* + * XXX - no locking, must be called just after pool_init. + */ +#ifdef DIAGNOSTIC + if (pp->pr_drain_hook != NULL) + panic("pool_set_drain_hook(%s): already set", pp->pr_wchan); +#endif + pp->pr_drain_hook = fn; + pp->pr_drain_hook_arg = fnarg; +} + static __inline struct pool_item_header * pool_alloc_item_header(struct pool *pp, caddr_t storage, int flags) { @@ -644,6 +660,19 @@ pool_get(struct pool *pp, int flags) } #endif if (__predict_false(pp->pr_nout == pp->pr_hardlimit)) { + if (pp->pr_drain_hook != NULL) { + /* + * Since the drain hook is likely to free memory + * to this pool unlock, call hook, relock and check + * hardlimit condition again. + */ + simple_unlock(&pp->pr_slock); + (*pp->pr_drain_hook)(pp->pr_drain_hook_arg, flags); + simple_lock(&pp->pr_slock); + if (pp->pr_nout < pp->pr_hardlimit) + goto startover; + } + if ((flags & PR_WAITOK) && !(flags & PR_LIMITFAIL)) { /* * XXX: A warning isn't logged in this case. Should @@ -1247,9 +1276,17 @@ pool_reclaim(struct pool *pp) if (pp->pr_roflags & PR_STATIC) return 0; + if (pp->pr_drain_hook != NULL) { + /* + * The drain hook must be called with the pool unlocked. + */ + (*pp->pr_drain_hook)(pp->pr_drain_hook_arg, PR_NOWAIT); + } + if (simple_lock_try(&pp->pr_slock) == 0) return 0; pr_enter(pp, file, line); + TAILQ_INIT(&pq); /* @@ -1905,8 +1942,19 @@ pool_allocator_alloc(struct pool *org, int flags) do { if ((res = (*pa->pa_alloc)(org, flags)) != NULL) return (res); - if ((flags & PR_WAITOK) == 0) + if ((flags & PR_WAITOK) == 0) { + /* + * We only run the drain hook here if PR_NOWAIT. + * In other cases the hook will be run in + * pool_reclaim. + */ + if (org->pr_drain_hook == NULL) + break; + (*org->pr_drain_hook)(org->pr_drain_hook_arg, flags); + if ((res = (*pa->pa_alloc)(org, flags)) != NULL) + continue; break; + } /* * Drain all pools, except 'org', that use this allocator. @@ -1917,6 +1965,8 @@ pool_allocator_alloc(struct pool *org, int flags) * have potentially sleeping pool_reclaim, non-sleeping * locks on pool_allocator and some stirring of drained * pools in the allocator. + * XXX - maybe we should use pool_head_slock for locking + * the allocators? */ freed = 0; |