Gitweb:
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=314de8a9e17f70243eacc80d2dd22a5d74b09fce
Commit: 314de8a9e17f70243eacc80d2dd22a5d74b09fce
Parent: f433dc56344cb72cc3de5ba0819021cec3aef807
Author: Mathieu Desnoyers <[EMAIL PROTECTED]>
AuthorDate: Wed Nov 14 16:59:48 2007 -0800
Committer: Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Wed Nov 14 18:45:40 2007 -0800
Linux Kernel Markers: fix marker mutex not taken upon module load
Upon module load, we must take the markers mutex. It implies that the
marker
mutex must be nested inside the module mutex.
It implies changing the nesting order : now the marker mutex nests inside
the
module mutex. Make the necessary changes to reverse the order in which the
mutexes are taken.
Includes some cleanup from Dave Hansen <[EMAIL PROTECTED]>.
Signed-off-by: Mathieu Desnoyers <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
---
kernel/marker.c | 41 +++++++++++++++++------------------------
1 files changed, 17 insertions(+), 24 deletions(-)
diff --git a/kernel/marker.c b/kernel/marker.c
index ccb48d9..5323cfa 100644
--- a/kernel/marker.c
+++ b/kernel/marker.c
@@ -28,7 +28,7 @@ extern struct marker __start___markers[];
extern struct marker __stop___markers[];
/*
- * module_mutex nests inside markers_mutex. Markers mutex protects the builtin
+ * markers_mutex nests inside module_mutex. Markers mutex protects the builtin
* and module markers, the hash table and deferred_sync.
*/
static DEFINE_MUTEX(markers_mutex);
@@ -257,7 +257,6 @@ static void disable_marker(struct marker *elem)
* @refcount: number of references left to the given probe_module (out)
*
* Updates the probe callback corresponding to a range of markers.
- * Must be called with markers_mutex held.
*/
void marker_update_probe_range(struct marker *begin,
struct marker *end, struct module *probe_module,
@@ -266,6 +265,7 @@ void marker_update_probe_range(struct marker *begin,
struct marker *iter;
struct marker_entry *mark_entry;
+ mutex_lock(&markers_mutex);
for (iter = begin; iter < end; iter++) {
mark_entry = get_marker(iter->name);
if (mark_entry && mark_entry->refcount) {
@@ -281,6 +281,7 @@ void marker_update_probe_range(struct marker *begin,
disable_marker(iter);
}
}
+ mutex_unlock(&markers_mutex);
}
/*
@@ -293,7 +294,6 @@ static void marker_update_probes(struct module
*probe_module)
{
int refcount = 0;
- mutex_lock(&markers_mutex);
/* Core kernel markers */
marker_update_probe_range(__start___markers,
__stop___markers, probe_module, &refcount);
@@ -303,7 +303,6 @@ static void marker_update_probes(struct module
*probe_module)
synchronize_sched();
deferred_sync = 0;
}
- mutex_unlock(&markers_mutex);
}
/**
@@ -320,7 +319,7 @@ int marker_probe_register(const char *name, const char
*format,
marker_probe_func *probe, void *private)
{
struct marker_entry *entry;
- int ret = 0, need_update = 0;
+ int ret = 0;
mutex_lock(&markers_mutex);
entry = get_marker(name);
@@ -335,11 +334,11 @@ int marker_probe_register(const char *name, const char
*format,
ret = add_marker(name, format, probe, private);
if (ret)
goto end;
- need_update = 1;
+ mutex_unlock(&markers_mutex);
+ marker_update_probes(NULL);
+ return ret;
end:
mutex_unlock(&markers_mutex);
- if (need_update)
- marker_update_probes(NULL);
return ret;
}
EXPORT_SYMBOL_GPL(marker_probe_register);
@@ -355,7 +354,6 @@ void *marker_probe_unregister(const char *name)
struct module *probe_module;
struct marker_entry *entry;
void *private;
- int need_update = 0;
mutex_lock(&markers_mutex);
entry = get_marker(name);
@@ -368,11 +366,11 @@ void *marker_probe_unregister(const char *name)
probe_module = __module_text_address((unsigned long)entry->probe);
private = remove_marker(name);
deferred_sync = 1;
- need_update = 1;
+ mutex_unlock(&markers_mutex);
+ marker_update_probes(probe_module);
+ return private;
end:
mutex_unlock(&markers_mutex);
- if (need_update)
- marker_update_probes(probe_module);
return private;
}
EXPORT_SYMBOL_GPL(marker_probe_unregister);
@@ -392,7 +390,6 @@ void *marker_probe_unregister_private_data(void *private)
struct marker_entry *entry;
int found = 0;
unsigned int i;
- int need_update = 0;
mutex_lock(&markers_mutex);
for (i = 0; i < MARKER_TABLE_SIZE; i++) {
@@ -414,11 +411,11 @@ iter_end:
probe_module = __module_text_address((unsigned long)entry->probe);
private = remove_marker(entry->name);
deferred_sync = 1;
- need_update = 1;
+ mutex_unlock(&markers_mutex);
+ marker_update_probes(probe_module);
+ return private;
end:
mutex_unlock(&markers_mutex);
- if (need_update)
- marker_update_probes(probe_module);
return private;
}
EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data);
@@ -434,7 +431,7 @@ EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data);
int marker_arm(const char *name)
{
struct marker_entry *entry;
- int ret = 0, need_update = 0;
+ int ret = 0;
mutex_lock(&markers_mutex);
entry = get_marker(name);
@@ -447,11 +444,9 @@ int marker_arm(const char *name)
*/
if (entry->refcount++)
goto end;
- need_update = 1;
end:
mutex_unlock(&markers_mutex);
- if (need_update)
- marker_update_probes(NULL);
+ marker_update_probes(NULL);
return ret;
}
EXPORT_SYMBOL_GPL(marker_arm);
@@ -467,7 +462,7 @@ EXPORT_SYMBOL_GPL(marker_arm);
int marker_disarm(const char *name)
{
struct marker_entry *entry;
- int ret = 0, need_update = 0;
+ int ret = 0;
mutex_lock(&markers_mutex);
entry = get_marker(name);
@@ -486,11 +481,9 @@ int marker_disarm(const char *name)
ret = -EPERM;
goto end;
}
- need_update = 1;
end:
mutex_unlock(&markers_mutex);
- if (need_update)
- marker_update_probes(NULL);
+ marker_update_probes(NULL);
return ret;
}
EXPORT_SYMBOL_GPL(marker_disarm);
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
