From: Trond Myklebust Date: Thu, 5 Jun 2014 14:42:37 +0000 (-0400) Subject: NFS: Use raw_write_seqcount_begin/end int nfs4_reclaim_open_state X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=abbec2da13f0e4c5d9b78b7e2c025a3e617228ba;p=openwrt%2Fstaging%2Fblogic.git NFS: Use raw_write_seqcount_begin/end int nfs4_reclaim_open_state The addition of lockdep code to write_seqcount_begin/end has lead to a bunch of false positive claims of ABBA deadlocks with the so_lock spinlock. Audits show that this simply cannot happen because the read side code does not spin while holding so_lock. Cc: # 3.13.x Signed-off-by: Trond Myklebust --- diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 2349518eef2c..21275148fc13 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1456,7 +1456,7 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs * server that doesn't support a grace period. */ spin_lock(&sp->so_lock); - write_seqcount_begin(&sp->so_reclaim_seqcount); + raw_write_seqcount_begin(&sp->so_reclaim_seqcount); restart: list_for_each_entry(state, &sp->so_states, open_states) { if (!test_and_clear_bit(ops->state_flag_bit, &state->flags)) @@ -1519,13 +1519,13 @@ restart: spin_lock(&sp->so_lock); goto restart; } - write_seqcount_end(&sp->so_reclaim_seqcount); + raw_write_seqcount_end(&sp->so_reclaim_seqcount); spin_unlock(&sp->so_lock); return 0; out_err: nfs4_put_open_state(state); spin_lock(&sp->so_lock); - write_seqcount_end(&sp->so_reclaim_seqcount); + raw_write_seqcount_end(&sp->so_reclaim_seqcount); spin_unlock(&sp->so_lock); return status; }