lockdep: annotate journal_start()

On Fri, 2007-07-13 at 02:05 -0700, Andrew Morton wrote:

> Except lockdep doesn't know about journal_start(), which has ranking
> requirements similar to a semaphore.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index 772b653..8df5bac 100644 (file)
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -233,6 +233,8 @@ out:
        return ret;
 }
 
+static struct lock_class_key jbd_handle_key;
+
 /* Allocate a new handle.  This should probably be in a slab... */
 static handle_t *new_handle(int nblocks)
 {
@@ -243,6 +245,8 @@ static handle_t *new_handle(int nblocks)
        handle->h_buffer_credits = nblocks;
        handle->h_ref = 1;
 
+       lockdep_init_map(&handle->h_lockdep_map, "jbd_handle", &jbd_handle_key, 0);
+
        return handle;
 }
 
@@ -286,6 +290,9 @@ handle_t *journal_start(journal_t *journal, int nblocks)
                current->journal_info = NULL;
                handle = ERR_PTR(err);
        }
+
+       lock_acquire(&handle->h_lockdep_map, 0, 0, 0, 2, _THIS_IP_);
+
        return handle;
 }
 
@@ -1411,6 +1418,8 @@ int journal_stop(handle_t *handle)
                spin_unlock(&journal->j_state_lock);
        }
 
+       lock_release(&handle->h_lockdep_map, 1, _THIS_IP_);
+
        jbd_free_handle(handle);
        return err;
 }

diff --git a/include/linux/jbd.h b/include/linux/jbd.h
index 4527375..700a93b 100644 (file)
--- a/include/linux/jbd.h
+++ b/include/linux/jbd.h
@@ -30,6 +30,7 @@
 #include <linux/bit_spinlock.h>
 #include <linux/mutex.h>
 #include <linux/timer.h>
+#include <linux/lockdep.h>
 
 #include <asm/semaphore.h>
 #endif
@@ -396,6 +397,10 @@ struct handle_s
        unsigned int    h_sync:         1;      /* sync-on-close */
        unsigned int    h_jdata:        1;      /* force data journaling */
        unsigned int    h_aborted:      1;      /* fatal error on handle */
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+       struct lockdep_map      h_lockdep_map;
+#endif
 };