On Tue, 2023-02-14 at 14:48 +0000, Chuck Lever III wrote:

quoted

On Feb 13, 2023, at 3:23 PM, Jeff Layton [off-list ref]
wrote:

There's no reason to delay reaping an nfsd_file just because its
underlying inode is still under writeback. nfsd just relies on
client
activity or the local flusher threads to do writeback.

Holding the file open does nothing to facilitate that, nor does it
help
with tracking errors. Just allow it to close and let the kernel do
writeback as it normally would.

Signed-off-by: Jeff Layton <jlayton@kernel.org>

Thanks! Applied to topic-filecache-cleanups.

quoted

---
fs/nfsd/filecache.c | 22 ----------------------
1 file changed, 22 deletions(-)

diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index e6617431df7c..3b9a10378c83 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c

@@ -296,19 +296,6 @@ nfsd_file_free(struct nfsd_file *nf)

        call_rcu(&nf->nf_rcu, nfsd_file_slab_free);
}

-static bool
-nfsd_file_check_writeback(struct nfsd_file *nf)
-{
-       struct file *file = nf->nf_file;
-       struct address_space *mapping;
-
-       if (!file || !(file->f_mode & FMODE_WRITE))
-               return false;
-       mapping = file->f_mapping;
-       return mapping_tagged(mapping, PAGECACHE_TAG_DIRTY) ||
-               mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK);
-}
-
static bool nfsd_file_lru_add(struct nfsd_file *nf)
{
        set_bit(NFSD_FILE_REFERENCED, &nf->nf_flags);

@@ -438,15 +425,6 @@ nfsd_file_lru_cb(struct list_head *item,

struct list_lru_one *lru,
        /* We should only be dealing with GC entries here */
        WARN_ON_ONCE(!test_bit(NFSD_FILE_GC, &nf->nf_flags));

-       /*
-        * Don't throw out files that are still undergoing I/O or
-        * that have uncleared errors pending.
-        */
-       if (nfsd_file_check_writeback(nf)) {
-               trace_nfsd_file_gc_writeback(nf);
-               return LRU_SKIP;
-       }
-
        /* If it was recently added to the list, skip it */
        if (test_and_clear_bit(NFSD_FILE_REFERENCED, &nf-

quoted

nf_flags)) {

                trace_nfsd_file_gc_referenced(nf);
-- 
2.39.1

--
Chuck Lever

Wait... There is a good reason for wanting to do this in the case of
NFS re-exports, since close() is a very expensive operation if the file
has dirty data.

-- 
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@hammerspace.com