[PATCH] lockdep: annotate sk_locks
Teach sk_lock semantics to the lock validator. In the softirq path the
slock has mutex_trylock()+mutex_unlock() semantics, in the process context
sock_lock() case it has mutex_lock()/mutex_unlock() semantics.
Thus we treat sock_owned_by_user() flagged areas as an exclusion area too,
not just those areas covered by a held sk_lock.slock.
Effect on non-lockdep kernels: minimal, sk_lock_sock_init() has been turned
into an inline function.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/net/sock.h b/include/net/sock.h
index 0969fb6..324b3ea 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -44,6 +44,7 @@
#include <linux/timer.h>
#include <linux/cache.h>
#include <linux/module.h>
+#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h> /* struct sk_buff */
#include <linux/security.h>
@@ -78,18 +79,17 @@
spinlock_t slock;
struct sock_iocb *owner;
wait_queue_head_t wq;
+ /*
+ * We express the mutex-alike socket_lock semantics
+ * to the lock validator by explicitly managing
+ * the slock as a lock variant (in addition to
+ * the slock itself):
+ */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ struct lockdep_map dep_map;
+#endif
} socket_lock_t;
-extern struct lock_class_key af_family_keys[AF_MAX];
-
-#define sock_lock_init(__sk) \
-do { spin_lock_init(&((__sk)->sk_lock.slock)); \
- lockdep_set_class(&(__sk)->sk_lock.slock, \
- af_family_keys + (__sk)->sk_family); \
- (__sk)->sk_lock.owner = NULL; \
- init_waitqueue_head(&((__sk)->sk_lock.wq)); \
-} while(0)
-
struct sock;
struct proto;