diff options
| author |   Omar Sandoval <osandov@fb.com> | 2019-09-16 11:30:58 -0700 |
|---|---|---|
| committer |   David Sterba <dsterba@suse.com> | 2019-11-18 12:46:49 +0100 |
| commit | c9eb55db8439057165f106164622c146cdd59468 (patch) | |
| tree | baf390f2f39d5262b7bfaa43df57bc30945dd7ad /include/trace | |
| parent | btrfs: get rid of unique workqueue helper functions (diff) | |
| download | linux-dev-c9eb55db8439057165f106164622c146cdd59468.tar.xz linux-dev-c9eb55db8439057165f106164622c146cdd59468.zip | |
btrfs: get rid of pointless wtag variable in async-thread.c
Commit ac0c7cf8be00 ("btrfs: fix crash when tracepoint arguments are
freed by wq callbacks") added a void pointer, wtag, which is passed into
trace_btrfs_all_work_done() instead of the freed work item. This is
silly for a few reasons:
1. The freed work item still has the same address.
2. work is still in scope after it's freed, so assigning wtag doesn't
stop anyone from using it.
3. The tracepoint has always taken a void * argument, so assigning wtag
doesn't actually make things any more type-safe. (Note that the
original bug in commit bc074524e123 ("btrfs: prefix fsid to all trace
events") was that the void * was implicitly casted when it was passed
to btrfs_work_owner() in the trace point itself).
Instead, let's add some clearer warnings as comments.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'include/trace')
| -rw-r--r-- | include/trace/events/btrfs.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h index 75ae1899452b..8ca7401bc2fb 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -1389,9 +1389,9 @@ DECLARE_EVENT_CLASS(btrfs__work, ); /* - * For situiations when the work is freed, we pass fs_info and a tag that that - * matches address of the work structure so it can be paired with the - * scheduling event. + * For situations when the work is freed, we pass fs_info and a tag that matches + * the address of the work structure so it can be paired with the scheduling + * event. DO NOT add anything here that dereferences wtag. */ DECLARE_EVENT_CLASS(btrfs__work__done, |