From 7210cb7a72a22303cdb225bd1aea28697a17bbae Mon Sep 17 00:00:00 2001
From: David Teigland <teigland@redhat.com>
Date: Thu, 8 Mar 2012 12:37:12 -0600
Subject: [PATCH] dlm: fix slow rsb search in dir recovery
The function used to find an rsb during directory
recovery was searching the single linear list of
rsb's. This wasted a lot of time compared to
using the standard hash table to find the rsb.
Signed-off-by: David Teigland <teigland@redhat.com>
---
fs/dlm/dir.c | 17 +++++++++++++++++
fs/dlm/lock.c | 8 ++++----
fs/dlm/lock.h | 3 +++
3 files changed, 24 insertions(+), 4 deletions(-)
diff --git a/fs/dlm/dir.c b/fs/dlm/dir.c
index 83641574b016..dc5eb598b81f 100644
--- a/fs/dlm/dir.c
+++ b/fs/dlm/dir.c
@@ -351,11 +351,28 @@ int dlm_dir_lookup(struct dlm_ls *ls, int nodeid, char *name, int namelen,
static struct dlm_rsb *find_rsb_root(struct dlm_ls *ls, char *name, int len)
{
struct dlm_rsb *r;
+ uint32_t hash, bucket;
+ int rv;
+
+ hash = jhash(name, len, 0);
+ bucket = hash & (ls->ls_rsbtbl_size - 1);
+
+ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[bucket].keep, name, len, 0, &r);
+ if (rv)
+ rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[bucket].toss,
+ name, len, 0, &r);
+ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+
+ if (!rv)
+ return r;
down_read(&ls->ls_root_sem);
list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
if (len == r->res_length && !memcmp(name, r->res_name, len)) {
up_read(&ls->ls_root_sem);
+ log_error(ls, "find_rsb_root revert to root_list %s",
+ r->res_name);
return r;
}
}
diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index d47183043c59..fa5c07d51dcc 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -411,8 +411,8 @@ static int rsb_cmp(struct dlm_rsb *r, const char *name, int nlen)
return memcmp(r->res_name, maxname, DLM_RESNAME_MAXLEN);
}
-static int search_rsb_tree(struct rb_root *tree, char *name, int len,
- unsigned int flags, struct dlm_rsb **r_ret)
+int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
+ unsigned int flags, struct dlm_rsb **r_ret)
{
struct rb_node *node = tree->rb_node;
struct dlm_rsb *r;
@@ -474,12 +474,12 @@ static int _search_rsb(struct dlm_ls *ls, char *name, int len, int b,
struct dlm_rsb *r;
int error;
- error = search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, flags, &r);
+ error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].keep, name, len, flags, &r);
if (!error) {
kref_get(&r->res_ref);
goto out;
}
- error = search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, flags, &r);
+ error = dlm_search_rsb_tree(&ls->ls_rsbtbl[b].toss, name, len, flags, &r);
if (error)
goto out;
diff --git a/fs/dlm/lock.h b/fs/dlm/lock.h
index 265017a7c3e7..1a255307f6ff 100644
--- a/fs/dlm/lock.h
+++ b/fs/dlm/lock.h
@@ -28,6 +28,9 @@ void dlm_scan_waiters(struct dlm_ls *ls);
void dlm_scan_timeout(struct dlm_ls *ls);
void dlm_adjust_timeouts(struct dlm_ls *ls);
+int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
+ unsigned int flags, struct dlm_rsb **r_ret);
+
int dlm_purge_locks(struct dlm_ls *ls);
void dlm_purge_mstcpy_locks(struct dlm_rsb *r);
void dlm_grant_after_purge(struct dlm_ls *ls);
--
2.30.9