From f11722834605a155022a8098ad7d8adacf44b22f Mon Sep 17 00:00:00 2001 From: David Teigland Date: Mon, 7 Jan 2013 11:03:42 -0600 Subject: dlm: avoid scanning unchanged toss lists Keep track of whether a toss list contains any shrinkable rsbs. If not, dlm_scand can avoid scanning the list for rsbs to shrink. Unnecessary scanning can otherwise waste a lot of time because the toss lists can contain a large number of rsbs that are non-shrinkable (directory records). Signed-off-by: David Teigland --- fs/dlm/dlm_internal.h | 3 +++ fs/dlm/lock.c | 15 +++++++++++++++ 2 files changed, 18 insertions(+) (limited to 'fs/dlm') diff --git a/fs/dlm/dlm_internal.h b/fs/dlm/dlm_internal.h index 77c0f70f8fe8..e7665c31f7b1 100644 --- a/fs/dlm/dlm_internal.h +++ b/fs/dlm/dlm_internal.h @@ -96,10 +96,13 @@ do { \ } +#define DLM_RTF_SHRINK 0x00000001 + struct dlm_rsbtable { struct rb_root keep; struct rb_root toss; spinlock_t lock; + uint32_t flags; }; diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c index a579f30f237d..f7501651762d 100644 --- a/fs/dlm/lock.c +++ b/fs/dlm/lock.c @@ -1132,6 +1132,7 @@ static void toss_rsb(struct kref *kref) rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[r->res_bucket].keep); rsb_insert(r, &ls->ls_rsbtbl[r->res_bucket].toss); r->res_toss_time = jiffies; + ls->ls_rsbtbl[r->res_bucket].flags |= DLM_RTF_SHRINK; if (r->res_lvbptr) { dlm_free_lvb(r->res_lvbptr); r->res_lvbptr = NULL; @@ -1659,11 +1660,18 @@ static void shrink_bucket(struct dlm_ls *ls, int b) char *name; int our_nodeid = dlm_our_nodeid(); int remote_count = 0; + int need_shrink = 0; int i, len, rv; memset(&ls->ls_remove_lens, 0, sizeof(int) * DLM_REMOVE_NAMES_MAX); spin_lock(&ls->ls_rsbtbl[b].lock); + + if (!(ls->ls_rsbtbl[b].flags & DLM_RTF_SHRINK)) { + spin_unlock(&ls->ls_rsbtbl[b].lock); + return; + } + for (n = rb_first(&ls->ls_rsbtbl[b].toss); n; n = next) { next = rb_next(n); r = rb_entry(n, struct dlm_rsb, res_hashnode); @@ -1679,6 +1687,8 @@ static void shrink_bucket(struct dlm_ls *ls, int b) continue; } + need_shrink = 1; + if (!time_after_eq(jiffies, r->res_toss_time + dlm_config.ci_toss_secs * HZ)) { continue; @@ -1710,6 +1720,11 @@ static void shrink_bucket(struct dlm_ls *ls, int b) rb_erase(&r->res_hashnode, &ls->ls_rsbtbl[b].toss); dlm_free_rsb(r); } + + if (need_shrink) + ls->ls_rsbtbl[b].flags |= DLM_RTF_SHRINK; + else + ls->ls_rsbtbl[b].flags &= ~DLM_RTF_SHRINK; spin_unlock(&ls->ls_rsbtbl[b].lock); /* -- cgit v1.2.3-59-g8ed1b