[PATCH] jbd: avoid kfree(NULL)
There are a couple of places where JBD has to check to see whether an unneeded
memory allocation was performed. Usually it _was_ needed, so we end up
calling kfree(NULL). We can micro-optimise that by checking the pointer
before calling kfree().
Thanks to Steven Rostedt <rostedt@goodmis.org> for identifying this.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index ff75afe..508b2ea 100644
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -227,7 +227,8 @@
spin_unlock(&transaction->t_handle_lock);
spin_unlock(&journal->j_state_lock);
out:
- kfree(new_transaction);
+ if (unlikely(new_transaction)) /* It's usually NULL */
+ kfree(new_transaction);
return ret;
}
@@ -724,7 +725,8 @@
journal_cancel_revoke(handle, jh);
out:
- kfree(frozen_buffer);
+ if (unlikely(frozen_buffer)) /* It's usually NULL */
+ kfree(frozen_buffer);
JBUFFER_TRACE(jh, "exit");
return error;
@@ -903,7 +905,8 @@
jbd_unlock_bh_state(bh);
out:
journal_put_journal_head(jh);
- kfree(committed_data);
+ if (unlikely(committed_data))
+ kfree(committed_data);
return err;
}