From ed14dd4d80ae32635cee501a0e2f33bffe1872ab Mon Sep 17 00:00:00 2001
From: shadow <shadow>
Date: Fri, 4 Jul 2008 07:42:10 +0000
Subject: [PATCH] add recount protection for osc callbacks, so avoid panic on
shutdown
Branch HEAD
b=15210
i=green
i=umka
---
lustre/ChangeLog | 4 ++++
lustre/include/lustre_cache.h | 2 ++
lustre/osc/cache.c | 41 +++++++++++++++++++++++++++++++----
3 files changed, 43 insertions(+), 4 deletions(-)
diff --git a/lustre/ChangeLog b/lustre/ChangeLog
index d281ffde65..02d8d73086 100644
--- a/lustre/ChangeLog
+++ b/lustre/ChangeLog
@@ -12,6 +12,10 @@ tbd Sun Microsystems, Inc.
* RHEL 4 and RHEL 5/SLES 10 clients behaves differently on 'cd' to a
removed cwd "./" (refer to Bugzilla 14399).
+Severity : normal
+Bugzilla : 15210
+Description: add recount protection for osc callbacks, so avoid panic on shutdown
+
Severity : normal
Bugzilla : 12653
Description: sanity test 65a fails if stripecount of -1 is set
diff --git a/lustre/include/lustre_cache.h b/lustre/include/lustre_cache.h
index 291d882936..d5a5337bd2 100644
--- a/lustre/include/lustre_cache.h
+++ b/lustre/include/lustre_cache.h
@@ -13,6 +13,7 @@ struct osc_async_page;
struct page_removal_cb_element {
struct list_head prce_list;
obd_page_removal_cb_t prce_callback;
+ atomic_t prce_refcnt;
};
typedef int (*cache_iterate_extents_cb_t)(struct lustre_cache *,
@@ -27,6 +28,7 @@ struct lustre_cache {
struct list_head lc_locks_list;
spinlock_t lc_locks_list_lock;
struct list_head lc_page_removal_callback_list;
+ rwlock_t lc_page_removal_cb_lock; /* iterate vs modify list */
struct obd_device *lc_obd;
obd_pin_extent_cb lc_pin_extent_cb;
};
diff --git a/lustre/osc/cache.c b/lustre/osc/cache.c
index 3dc93fb72f..25869743c0 100644
--- a/lustre/osc/cache.c
+++ b/lustre/osc/cache.c
@@ -138,16 +138,39 @@ int cache_add_extent(struct lustre_cache *cache, struct ldlm_res_id *res,
RETURN(0);
}
+static void cache_extent_removal_get(struct page_removal_cb_element *element)
+{
+ atomic_inc(&element->prce_refcnt);
+}
+
+static void cache_extent_removal_put(struct page_removal_cb_element *element)
+{
+ if(atomic_dec_and_test(&element->prce_refcnt))
+ OBD_FREE_PTR(element);
+}
+
static int cache_extent_removal_event(struct lustre_cache *cache,
void *data, int discard)
{
struct page *page = data;
+ struct list_head *iter;
struct page_removal_cb_element *element;
- list_for_each_entry(element, &cache->lc_page_removal_callback_list,
- prce_list) {
+ read_lock(&cache->lc_page_removal_cb_lock);
+ iter = cache->lc_page_removal_callback_list.next;
+ while(iter != &cache->lc_page_removal_callback_list) {
+ element = list_entry(iter, struct page_removal_cb_element, prce_list);
+ cache_extent_removal_get(element);
+ read_unlock(&cache->lc_page_removal_cb_lock);
+
element->prce_callback(page, discard);
+
+ read_lock(&cache->lc_page_removal_cb_lock);
+ iter = iter->next;
+ cache_extent_removal_put(element);
}
+ read_unlock(&cache->lc_page_removal_cb_lock);
+
return 0;
}
@@ -167,12 +190,17 @@ int cache_add_extent_removal_cb(struct lustre_cache *cache,
if (!func_cb)
return 0;
- OBD_ALLOC(element, sizeof(*element));
+
+ OBD_ALLOC_PTR(element);
if (!element)
return -ENOMEM;
element->prce_callback = func_cb;
+ atomic_set(&element->prce_refcnt, 1);
+
+ write_lock(&cache->lc_page_removal_cb_lock);
list_add_tail(&element->prce_list,
&cache->lc_page_removal_callback_list);
+ write_unlock(&cache->lc_page_removal_cb_lock);
cache->lc_pin_extent_cb = pin_cb;
return 0;
@@ -188,17 +216,21 @@ int cache_del_extent_removal_cb(struct lustre_cache *cache,
int found = 0;
struct page_removal_cb_element *element, *t;
+ write_lock(&cache->lc_page_removal_cb_lock);
list_for_each_entry_safe(element, t,
&cache->lc_page_removal_callback_list,
prce_list) {
if (element->prce_callback == func_cb) {
list_del(&element->prce_list);
- OBD_FREE(element, sizeof(*element));
+ write_unlock(&cache->lc_page_removal_cb_lock);
found = 1;
+ cache_extent_removal_put(element);
+ write_lock(&cache->lc_page_removal_cb_lock);
/* We continue iterating the list in case this function
was registered more than once */
}
}
+ write_unlock(&cache->lc_page_removal_cb_lock);
if (list_empty(&cache->lc_page_removal_callback_list))
cache->lc_pin_extent_cb = NULL;
@@ -358,6 +390,7 @@ struct lustre_cache *cache_create(struct obd_device *obd)
spin_lock_init(&cache->lc_locks_list_lock);
CFS_INIT_LIST_HEAD(&cache->lc_locks_list);
CFS_INIT_LIST_HEAD(&cache->lc_page_removal_callback_list);
+ rwlock_init(&cache->lc_page_removal_cb_lock);
cache->lc_obd = obd;
out:
--
GitLab