diff options
| -rw-r--r-- | fs/ceph/caps.c | 88 |
1 files changed, 59 insertions, 29 deletions
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index b9b5c47efd06..25141b6683e9 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -184,36 +184,54 @@ int ceph_reserve_caps(struct ceph_mds_client *mdsc, mdsc->caps_avail_count); spin_unlock(&mdsc->caps_list_lock); - for (i = have; i < need; i++) { -retry: + for (i = have; i < need; ) { cap = kmem_cache_alloc(ceph_cap_cachep, GFP_NOFS); - if (!cap) { - if (!trimmed) { - for (j = 0; j < mdsc->max_sessions; j++) { - s = __ceph_lookup_mds_session(mdsc, j); - if (!s) - continue; - mutex_unlock(&mdsc->mutex); + if (cap) { + list_add(&cap->caps_item, &newcaps); + alloc++; + i++; + continue; + } - mutex_lock(&s->s_mutex); - max_caps = s->s_nr_caps - (need - i); - ceph_trim_caps(mdsc, s, max_caps); - mutex_unlock(&s->s_mutex); + if (!trimmed) { + for (j = 0; j < mdsc->max_sessions; j++) { + s = __ceph_lookup_mds_session(mdsc, j); + if (!s) + continue; + mutex_unlock(&mdsc->mutex); - ceph_put_mds_session(s); - mutex_lock(&mdsc->mutex); - } - trimmed = true; - goto retry; - } else { - pr_warn("reserve caps ctx=%p ENOMEM " - "need=%d got=%d\n", - ctx, need, have + alloc); - goto out_nomem; + mutex_lock(&s->s_mutex); + max_caps = s->s_nr_caps - (need - i); + ceph_trim_caps(mdsc, s, max_caps); + mutex_unlock(&s->s_mutex); + + ceph_put_mds_session(s); + mutex_lock(&mdsc->mutex); } + trimmed = true; + + spin_lock(&mdsc->caps_list_lock); + if (mdsc->caps_avail_count) { + int more_have; + if (mdsc->caps_avail_count >= need - i) + more_have = need - i; + else + more_have = mdsc->caps_avail_count; + + i += more_have; + have += more_have; + mdsc->caps_avail_count -= more_have; + mdsc->caps_reserve_count += more_have; + + } + spin_unlock(&mdsc->caps_list_lock); + + continue; } - list_add(&cap->caps_item, &newcaps); - alloc++; + + pr_warn("reserve caps ctx=%p ENOMEM need=%d got=%d\n", + ctx, need, have + alloc); + goto out_nomem; } BUG_ON(have + alloc != need); @@ -234,16 +252,28 @@ retry: return 0; out_nomem: + + spin_lock(&mdsc->caps_list_lock); + mdsc->caps_avail_count += have; + mdsc->caps_reserve_count -= have; + while (!list_empty(&newcaps)) { cap = list_first_entry(&newcaps, struct ceph_cap, caps_item); list_del(&cap->caps_item); - kmem_cache_free(ceph_cap_cachep, cap); + + /* Keep some preallocated caps around (ceph_min_count), to + * avoid lots of free/alloc churn. */ + if (mdsc->caps_avail_count >= + mdsc->caps_reserve_count + mdsc->caps_min_count) { + kmem_cache_free(ceph_cap_cachep, cap); + } else { + mdsc->caps_avail_count++; + mdsc->caps_total_count++; + list_add(&cap->caps_item, &mdsc->caps_list); + } } - spin_lock(&mdsc->caps_list_lock); - mdsc->caps_avail_count += have; - mdsc->caps_reserve_count -= have; BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count + mdsc->caps_reserve_count + mdsc->caps_avail_count); |