lkml.org 
[lkml]   [2017]   [Jul]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 03/20] staging: lustre: ldlm: crash on umount in cleanup_resource
Date
From: Andriy Skulysh <andriy.skulysh@seagate.com>

cfs_hash_for_each_relax() assumes that cfs_hash_put_locked()
doesn't release bd lock, but it isn't true for
ldlm_res_hop_put_locked().

Add recfcount on next hnode in cfs_hash_for_each_relax() and
remove ldlm_res_hop_put_locked()

Signed-off-by: Andriy Skulysh <andriy.skulysh@seagate.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6304
Xyratex-bug-id: MRP-2352
Reviewed-by: Vitaly Fertman <vitaly.fertman@seagate.com>
Reviewed-by: Alexander Boyko <alexander.boyko@seagate.com>
Tested-by: Alexander Lezhoev <alexander.lezhoev@seagate.com>
Reviewed-on: http://review.whamcloud.com/13908
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
---
drivers/staging/lustre/lnet/libcfs/hash.c | 47 ++++++++++++++--------
drivers/staging/lustre/lustre/ldlm/ldlm_internal.h | 3 --
drivers/staging/lustre/lustre/ldlm/ldlm_resource.c | 43 --------------------
3 files changed, 31 insertions(+), 62 deletions(-)

diff --git a/drivers/staging/lustre/lnet/libcfs/hash.c b/drivers/staging/lustre/lnet/libcfs/hash.c
index 5c2ce2e..ff54eaf 100644
--- a/drivers/staging/lustre/lnet/libcfs/hash.c
+++ b/drivers/staging/lustre/lnet/libcfs/hash.c
@@ -1008,7 +1008,7 @@ struct cfs_hash *
LASSERT(ops->hs_object);
LASSERT(ops->hs_keycmp);
LASSERT(ops->hs_get);
- LASSERT(ops->hs_put_locked);
+ LASSERT(ops->hs_put || ops->hs_put_locked);

if (flags & CFS_HASH_REHASH)
flags |= CFS_HASH_COUNTER; /* must have counter */
@@ -1553,19 +1553,20 @@ struct cfs_hash_cond_arg {
cfs_hash_for_each_relax(struct cfs_hash *hs, cfs_hash_for_each_cb_t func,
void *data, int start)
{
+ struct hlist_node *next = NULL;
struct hlist_node *hnode;
- struct hlist_node *tmp;
struct cfs_hash_bd bd;
u32 version;
int count = 0;
int stop_on_change;
+ int has_put_locked;
int end = -1;
int rc = 0;
int i;

stop_on_change = cfs_hash_with_rehash_key(hs) ||
- !cfs_hash_with_no_itemref(hs) ||
- !hs->hs_ops->hs_put_locked;
+ !cfs_hash_with_no_itemref(hs);
+ has_put_locked = hs->hs_ops->hs_put_locked != NULL;
cfs_hash_lock(hs, 0);
again:
LASSERT(!cfs_hash_is_rehashing(hs));
@@ -1582,38 +1583,52 @@ struct cfs_hash_cond_arg {
version = cfs_hash_bd_version_get(&bd);

cfs_hash_bd_for_each_hlist(hs, &bd, hhead) {
- for (hnode = hhead->first; hnode;) {
+ hnode = hhead->first;
+ if (!hnode)
+ continue;
+ cfs_hash_get(hs, hnode);
+
+ for (; hnode; hnode = next) {
cfs_hash_bucket_validate(hs, &bd, hnode);
- cfs_hash_get(hs, hnode);
+ next = hnode->next;
+ if (next)
+ cfs_hash_get(hs, next);
cfs_hash_bd_unlock(hs, &bd, 0);
cfs_hash_unlock(hs, 0);

rc = func(hs, &bd, hnode, data);
- if (stop_on_change)
+ if (stop_on_change || !has_put_locked)
cfs_hash_put(hs, hnode);
cond_resched();
count++;

cfs_hash_lock(hs, 0);
cfs_hash_bd_lock(hs, &bd, 0);
- if (!stop_on_change) {
- tmp = hnode->next;
- cfs_hash_put_locked(hs, hnode);
- hnode = tmp;
- } else { /* bucket changed? */
+ if (stop_on_change) {
if (version !=
cfs_hash_bd_version_get(&bd))
- break;
- /* safe to continue because no change */
- hnode = hnode->next;
+ rc = -EINTR;
+ } else if (has_put_locked) {
+ cfs_hash_put_locked(hs, hnode);
}
if (rc) /* callback wants to break iteration */
break;
}
- if (rc) /* callback wants to break iteration */
+ if (next) {
+ if (has_put_locked) {
+ cfs_hash_put_locked(hs, next);
+ next = NULL;
+ }
break;
+ } else if (rc) {
+ break;
+ }
}
cfs_hash_bd_unlock(hs, &bd, 0);
+ if (next && !has_put_locked) {
+ cfs_hash_put(hs, next);
+ next = NULL;
+ }
if (rc) /* callback wants to break iteration */
break;
}
diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h b/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h
index ec3b23c..2bf5c84 100644
--- a/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h
+++ b/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h
@@ -106,9 +106,6 @@ int ldlm_cancel_lru_local(struct ldlm_namespace *ns,
extern unsigned int ldlm_enqueue_min;
extern unsigned int ldlm_cancel_unused_locks_before_replay;

-/* ldlm_resource.c */
-int ldlm_resource_putref_locked(struct ldlm_resource *res);
-
/* ldlm_lock.c */

struct ldlm_cb_set_arg {
diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
index eab44dc..4e805e7 100644
--- a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
+++ b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
@@ -536,16 +536,6 @@ static void ldlm_res_hop_get_locked(struct cfs_hash *hs,
ldlm_resource_getref(res);
}

-static void ldlm_res_hop_put_locked(struct cfs_hash *hs,
- struct hlist_node *hnode)
-{
- struct ldlm_resource *res;
-
- res = hlist_entry(hnode, struct ldlm_resource, lr_hash);
- /* cfs_hash_for_each_nolock is the only chance we call it */
- ldlm_resource_putref_locked(res);
-}
-
static void ldlm_res_hop_put(struct cfs_hash *hs, struct hlist_node *hnode)
{
struct ldlm_resource *res;
@@ -561,7 +551,6 @@ static void ldlm_res_hop_put(struct cfs_hash *hs, struct hlist_node *hnode)
.hs_keycpy = NULL,
.hs_object = ldlm_res_hop_object,
.hs_get = ldlm_res_hop_get_locked,
- .hs_put_locked = ldlm_res_hop_put_locked,
.hs_put = ldlm_res_hop_put
};

@@ -572,7 +561,6 @@ static void ldlm_res_hop_put(struct cfs_hash *hs, struct hlist_node *hnode)
.hs_keycpy = NULL,
.hs_object = ldlm_res_hop_object,
.hs_get = ldlm_res_hop_get_locked,
- .hs_put_locked = ldlm_res_hop_put_locked,
.hs_put = ldlm_res_hop_put
};

@@ -1249,37 +1237,6 @@ int ldlm_resource_putref(struct ldlm_resource *res)
}
EXPORT_SYMBOL(ldlm_resource_putref);

-/* Returns 1 if the resource was freed, 0 if it remains. */
-int ldlm_resource_putref_locked(struct ldlm_resource *res)
-{
- struct ldlm_namespace *ns = ldlm_res_to_ns(res);
-
- LASSERT_ATOMIC_GT_LT(&res->lr_refcount, 0, LI_POISON);
- CDEBUG(D_INFO, "putref res: %p count: %d\n",
- res, atomic_read(&res->lr_refcount) - 1);
-
- if (atomic_dec_and_test(&res->lr_refcount)) {
- struct cfs_hash_bd bd;
-
- cfs_hash_bd_get(ldlm_res_to_ns(res)->ns_rs_hash,
- &res->lr_name, &bd);
- __ldlm_resource_putref_final(&bd, res);
- cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
- /* NB: ns_rs_hash is created with CFS_HASH_NO_ITEMREF,
- * so we should never be here while calling cfs_hash_del,
- * cfs_hash_for_each_nolock is the only case we can get
- * here, which is safe to release cfs_hash_bd_lock.
- */
- if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
- ns->ns_lvbo->lvbo_free(res);
- kmem_cache_free(ldlm_resource_slab, res);
-
- cfs_hash_bd_lock(ns->ns_rs_hash, &bd, 1);
- return 1;
- }
- return 0;
-}
-
/**
* Add a lock into a given resource into specified lock list.
*/
--
1.8.3.1
\
 
 \ /
  Last update: 2017-07-26 17:28    [W:0.115 / U:9.736 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site