Commit be20aa00 authored Nov 29, 2015 by Jeff Layton Committed by J. Bruce Fields Dec 16, 2015

nfsd: don't hold ls_mutex across a layout recall



We do need to serialize layout stateid morphing operations, but we
currently hold the ls_mutex across a layout recall which is pretty
ugly. It's also unnecessary -- once we've bumped the seqid and
copied it, we don't need to serialize the rest of the CB_LAYOUTRECALL
vs. anything else. Just drop the mutex once the copy is done.

This was causing a "workqueue leaked lock or atomic" warning and an
occasional deadlock.

There's more work to be done here but this fixes the immediate
regression.

Fixes: cc8a5532 "nfsd: serialize layout stateid morphing operations"
Cc: stable@vger.kernel.org
Reported-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

parent 8005c49d

fs/nfsd/nfs4layouts.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -616,6 +616,7 @@ nfsd4_cb_layout_prepare(struct nfsd4_callback *cb)

		mutex_lock(&ls->ls_mutex);
		nfs4_inc_and_copy_stateid(&ls->ls_recall_sid, &ls->ls_stid);
		mutex_unlock(&ls->ls_mutex);
		}

		static int
		@@ -659,7 +660,6 @@ nfsd4_cb_layout_release(struct nfsd4_callback *cb)

		trace_layout_recall_release(&ls->ls_stid.sc_stateid);

		mutex_unlock(&ls->ls_mutex);
		nfsd4_return_all_layouts(ls, &reaplist);
		nfsd4_free_layouts(&reaplist);
		nfs4_put_stid(&ls->ls_stid);

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