On Thu, 2010-08-05 at 10:26 +0800, Bian Naimeng wrote: > > On Wed, 2010-08-04 at 17:18 +0800, Bian Naimeng wrote: > >> We should clear NFS_DELEGATED_STATE bit for inode->open_states after return delegation. > >> > >> Signed-off-by: Bian Naimeng <biannm@xxxxxxxxxxxxxx> > >> > >> --- > >> fs/nfs/nfs4proc.c | 15 ++++++++++++++- > >> 1 files changed, 14 insertions(+), 1 deletions(-) > >> > >> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c > >> index 70015dd..76cdef4 100644 > >> --- a/fs/nfs/nfs4proc.c > >> +++ b/fs/nfs/nfs4proc.c > > ... snip ... > > >> > >> static struct nfs4_state *nfs4_try_open_cached(struct nfs4_opendata *opendata) > > > > It is way too late to clear the NFS_DELEGATED_STATE flag _after_ we've > > returned the delegation. We should be doing it as part of > > nfs_delegation_claim_opens(). > > > > Why isn't the following patch sufficient? > > > > Cheers > > Trond > > > > ---------------------------------------------------------------------------------- > > NFSv4: Remember to clear NFS_DELEGATED_STATE in nfs_delegation_claim_opens > > > > From: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> > > > > Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> > > --- > > > > fs/nfs/delegation.c | 4 ++-- > > 1 files changed, 2 insertions(+), 2 deletions(-) > > > > > > diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c > > index 3016345..56d5d1a 100644 > > --- a/fs/nfs/delegation.c > > +++ b/fs/nfs/delegation.c > > @@ -102,10 +102,10 @@ again: > > state = ctx->state; > > if (state == NULL) > > continue; > > - if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) > > - continue; > > if (memcmp(state->stateid.data, stateid->data, sizeof(state->stateid.data)) != 0) > > continue; > > + if (!test_and_clear_bit(NFS_DELEGATED_STATE, &state->flags)) > > + continue; > > get_nfs_open_context(ctx); > > spin_unlock(&inode->i_lock); > > err = nfs4_open_delegation_recall(ctx, state, stateid); > > > > Thanks Trond. > But why we must remove test_and_clear_bit behind memcmp? > > Always test_bit and memcmp have same result, and I think test_and_clear_bit is fast > than memcmp, so i suggest we should call test_and_clear_bit first. right? We can't clear the bit before the memcmp() test. What we could do is keep the current test_bit() and then do a clear_bit after the memcmp(). Cheers Trond -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
