[PATCH v6 05/12] NFSD: Prepare bucket pruning for additional eviction reasons

[Chuck Lever <cel@kernel.org>]

nfsd_prune_bucket_locked() combines its two eviction reasons,
memory pressure and RC_EXPIRE, in a single test and stops the walk
at the first entry the test does not evict. A reason that needs
its own handling, a tracepoint per reason or a test that must run
ahead of the stop, has nowhere to go.

Test each reason on its own and jump to a shared eviction label.
The walk still stops at the first entry no reason applies to.

Assisted-by: LLM
Signed-off-by: Chuck Lever <cel@kernel.org>
---
 fs/nfsd/nfscache.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index 4207c2e694db..27c369b1f11b 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -274,10 +274,13 @@ nfsd_prune_bucket_locked(struct nfsd_net *nn, struct nfsd_drc_bucket *b,
 
 	/* The bucket LRU is ordered oldest-first. */
 	list_for_each_entry_safe(rp, tmp, &b->lru_head, c_lru) {
-		if (atomic_read(&nn->num_drc_entries) <= nn->max_drc_entries &&
-		    time_before(expiry, rp->c_timestamp))
-			break;
+		if (atomic_read(&nn->num_drc_entries) > nn->max_drc_entries)
+			goto evict;
+		if (time_before_eq(rp->c_timestamp, expiry))
+			goto evict;
+		break;
 
+evict:
 		nfsd_cacherep_unlink_locked(nn, b, rp);
 		list_add(&rp->c_lru, dispose);
 

-- 
2.55.0