From nobody Sun Apr 5 13:04:15 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5CA33328B7F; Mon, 23 Feb 2026 17:10:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771866620; cv=none; b=U3qxHtkZ++lVRZDVpZD6H9kzeQy0NnqQjq8CqEq3XJHEtj2eVrl0tneAQAICHOkcjLaKN/ZzFveFSZqVb/7HLf23naJtqYlZvpo5DZOKD4q9Xtih3iM/KZTD1WG7/WRZMFLjV5VxxNQxJOMSRodIANKs8cvOLP1N2b8MiueZIOM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771866620; c=relaxed/simple; bh=33/7X3KkyPQB6+MoF02KVKFM3QLZsp57v/whKSIPst0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=p+6PgjSXjw5r8BEZOIeNUTsnrLsXVXGc6lHJ30dwowRfF/6Hi4f+kaIcyKHh+IGhIfK+ozOLBccfjYjuEaSwFl04TC9KwjuWZla+LN0Ty5oqXsuRiNMc4HIUhLOEBj8/k5iS1X0+zQswKVQ3iyrEuXVmFiS54zSHHHZxmwS8/j4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OPwdRWdm; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OPwdRWdm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EBC97C2BCAF; Mon, 23 Feb 2026 17:10:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771866619; bh=33/7X3KkyPQB6+MoF02KVKFM3QLZsp57v/whKSIPst0=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=OPwdRWdmHM6Y/nRVj4OygNpTkDUUbmZ4waDUHA2OVR2ErtK9AlyPbSZqioGkXDUhh TI+78SWwWNbu3NlBF5U1qKS43ySR2rfEdkCYHI/h8J7QRCyqSEaRw3JLdJpKeWS6w/ pNWT/ZBhL7dLbW+UawrYX9Tm9w90Nh5b/j5UZQ6R6QcR6Sc+wA4RSipajfiDQnUA37 MqnEazRVItnx5eUnX0GOUQQ596slmGkKXZ6cvpBBspCTvnxMlLtZZwmN/39o6mSG/x SPfFlOheJRDY+ZRhO8SMCqwR4PEPtcJo32QKciSVCjfooG61iFQqVIU5lF+cf+cAQl r4Qok67jCLoHQ== From: Jeff Layton Date: Mon, 23 Feb 2026 12:09:59 -0500 Subject: [PATCH v2 2/4] sunrpc: convert queue_lock from global spinlock to per-cache-detail lock Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260223-sunrpc-cache-v2-2-91fc827c4d33@kernel.org> References: <20260223-sunrpc-cache-v2-0-91fc827c4d33@kernel.org> In-Reply-To: <20260223-sunrpc-cache-v2-0-91fc827c4d33@kernel.org> To: Chuck Lever , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey , Trond Myklebust , Anna Schumaker Cc: linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Jeff Layton X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=7368; i=jlayton@kernel.org; h=from:subject:message-id; bh=33/7X3KkyPQB6+MoF02KVKFM3QLZsp57v/whKSIPst0=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBpnIn33oRpa7h3/u6/pYHwD8V4gO4D3dnAv6rXK YcP1KReqfWJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCaZyJ9wAKCRAADmhBGVaC FY8ZD/9b/cH/Sciv4JTaVlZsY1wejPTdT5BZoenzdsDL9h2lmRDzyb3cKLN/Rx4qLKengGJh3kQ hQ/zM50eYDPKpXer57wnxuAp2AQY0NwUWQ7FizdFni2SamJgJvAjPZiGx93rD0/EK+MXxwTGEOQ KDnfrSpzBvJ8mPDPlkMoE9ZMRr2jvLOZACfg/9I6gDiBtH5xDtmXD4mGzQlhFb7GpnoWuE13D8H 0Qt+iKs285doqN6vVfat8u5qVH+5PEgZI0uPBJ9ApSFMmqwts1+tKDl7GonoTee6NPhyHCcxy9O Y6udBjkKPmlEI6fCrKmFIiOx9l8XhbyCzkklKNE7yDnt/HjHwdrxZln3G0BWwx2Z6NNUoPQ5IDR VcLKYN42hTXV8qUscA3X8qZb4bQ5hgtysmqA/209YGRJYdr+vK79aKqZQkdFYecIvtpkpngZj5H fLQj/sECeiXBiWu0tOv45R2K0mevEAyGZjucT+yQXzhWRvK773DI43Y0sdeiFK8EzB726QjxzaK qUmMM8Jj2cdgC7MJoQN9YY4lZOP4ftb2HVQg+8rhU4Fv4va9lz3NzZlsq3wtJRlhvDSw6w3IrXu OslOZrugR7fkNUluMZmxzFwLyAgYpNYVaekDpfDopeBL8e4hd0hJqFytMtoBuQsLcRPbxdDKK3b eAybM6b1wISHWbg== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 The global queue_lock serializes all upcall queue operations across every cache_detail instance. Convert it to a per-cache-detail spinlock so that different caches (e.g. auth.unix.ip vs nfsd.fh) no longer contend with each other on queue operations. Signed-off-by: Jeff Layton --- include/linux/sunrpc/cache.h | 1 + net/sunrpc/cache.c | 47 ++++++++++++++++++++++------------------= ---- 2 files changed, 24 insertions(+), 24 deletions(-) diff --git a/include/linux/sunrpc/cache.h b/include/linux/sunrpc/cache.h index e783132e481ff2593fdc5d323f7b3a08f85d4cd8..3d32dd1f7b05d35562d2064fed6= 9877b3950fb51 100644 --- a/include/linux/sunrpc/cache.h +++ b/include/linux/sunrpc/cache.h @@ -113,6 +113,7 @@ struct cache_detail { =20 /* fields for communication over channel */ struct list_head queue; + spinlock_t queue_lock; =20 atomic_t writers; /* how many time is /channel open */ time64_t last_close; /* if no writers, when did last close */ diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 86b3fd5a429d77f7f917f398a02cb7a5ff8dd1e0..1cfaae488c6c67a9797511804e4= bbba16bcc70ae 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -400,6 +400,7 @@ void sunrpc_init_cache_detail(struct cache_detail *cd) { spin_lock_init(&cd->hash_lock); INIT_LIST_HEAD(&cd->queue); + spin_lock_init(&cd->queue_lock); spin_lock(&cache_list_lock); cd->nextcheck =3D 0; cd->entries =3D 0; @@ -803,8 +804,6 @@ void cache_clean_deferred(void *owner) * */ =20 -static DEFINE_SPINLOCK(queue_lock); - struct cache_queue { struct list_head list; int reader; /* if 0, then request */ @@ -847,7 +846,7 @@ static ssize_t cache_read(struct file *filp, char __use= r *buf, size_t count, inode_lock(inode); /* protect against multiple concurrent * readers on this file */ again: - spin_lock(&queue_lock); + spin_lock(&cd->queue_lock); /* need to find next request */ while (rp->q.list.next !=3D &cd->queue && list_entry(rp->q.list.next, struct cache_queue, list) @@ -856,7 +855,7 @@ static ssize_t cache_read(struct file *filp, char __use= r *buf, size_t count, list_move(&rp->q.list, next); } if (rp->q.list.next =3D=3D &cd->queue) { - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); inode_unlock(inode); WARN_ON_ONCE(rp->offset); return 0; @@ -865,7 +864,7 @@ static ssize_t cache_read(struct file *filp, char __use= r *buf, size_t count, WARN_ON_ONCE(rq->q.reader); if (rp->offset =3D=3D 0) rq->readers++; - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); =20 if (rq->len =3D=3D 0) { err =3D cache_request(cd, rq); @@ -876,9 +875,9 @@ static ssize_t cache_read(struct file *filp, char __use= r *buf, size_t count, =20 if (rp->offset =3D=3D 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) { err =3D -EAGAIN; - spin_lock(&queue_lock); + spin_lock(&cd->queue_lock); list_move(&rp->q.list, &rq->q.list); - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); } else { if (rp->offset + count > rq->len) count =3D rq->len - rp->offset; @@ -888,26 +887,26 @@ static ssize_t cache_read(struct file *filp, char __u= ser *buf, size_t count, rp->offset +=3D count; if (rp->offset >=3D rq->len) { rp->offset =3D 0; - spin_lock(&queue_lock); + spin_lock(&cd->queue_lock); list_move(&rp->q.list, &rq->q.list); - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); } err =3D 0; } out: if (rp->offset =3D=3D 0) { /* need to release rq */ - spin_lock(&queue_lock); + spin_lock(&cd->queue_lock); rq->readers--; if (rq->readers =3D=3D 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) { list_del(&rq->q.list); - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); cache_put(rq->item, cd); kfree(rq->buf); kfree(rq); } else - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); } if (err =3D=3D -EAGAIN) goto again; @@ -988,7 +987,7 @@ static __poll_t cache_poll(struct file *filp, poll_tabl= e *wait, if (!rp) return mask; =20 - spin_lock(&queue_lock); + spin_lock(&cd->queue_lock); =20 for (cq=3D &rp->q; &cq->list !=3D &cd->queue; cq =3D list_entry(cq->list.next, struct cache_queue, list)) @@ -996,7 +995,7 @@ static __poll_t cache_poll(struct file *filp, poll_tabl= e *wait, mask |=3D EPOLLIN | EPOLLRDNORM; break; } - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); return mask; } =20 @@ -1011,7 +1010,7 @@ static int cache_ioctl(struct inode *ino, struct file= *filp, if (cmd !=3D FIONREAD || !rp) return -EINVAL; =20 - spin_lock(&queue_lock); + spin_lock(&cd->queue_lock); =20 /* only find the length remaining in current request, * or the length of the next request @@ -1024,7 +1023,7 @@ static int cache_ioctl(struct inode *ino, struct file= *filp, len =3D cr->len - rp->offset; break; } - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); =20 return put_user(len, (int __user *)arg); } @@ -1046,9 +1045,9 @@ static int cache_open(struct inode *inode, struct fil= e *filp, rp->offset =3D 0; rp->q.reader =3D 1; =20 - spin_lock(&queue_lock); + spin_lock(&cd->queue_lock); list_add(&rp->q.list, &cd->queue); - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); } if (filp->f_mode & FMODE_WRITE) atomic_inc(&cd->writers); @@ -1064,7 +1063,7 @@ static int cache_release(struct inode *inode, struct = file *filp, if (rp) { struct cache_request *rq =3D NULL; =20 - spin_lock(&queue_lock); + spin_lock(&cd->queue_lock); if (rp->offset) { struct cache_queue *cq; for (cq =3D &rp->q; &cq->list !=3D &cd->queue; @@ -1086,7 +1085,7 @@ static int cache_release(struct inode *inode, struct = file *filp, rp->offset =3D 0; } list_del(&rp->q.list); - spin_unlock(&queue_lock); + spin_unlock(&cd->queue_lock); =20 if (rq) { cache_put(rq->item, cd); @@ -1113,7 +1112,7 @@ static void cache_dequeue(struct cache_detail *detail= , struct cache_head *ch) struct cache_request *cr; LIST_HEAD(dequeued); =20 - spin_lock(&queue_lock); + spin_lock(&detail->queue_lock); list_for_each_entry_safe(cq, tmp, &detail->queue, list) if (!cq->reader) { cr =3D container_of(cq, struct cache_request, q); @@ -1126,7 +1125,7 @@ static void cache_dequeue(struct cache_detail *detail= , struct cache_head *ch) continue; list_move(&cr->q.list, &dequeued); } - spin_unlock(&queue_lock); + spin_unlock(&detail->queue_lock); while (!list_empty(&dequeued)) { cr =3D list_entry(dequeued.next, struct cache_request, q.list); list_del(&cr->q.list); @@ -1251,7 +1250,7 @@ static int cache_pipe_upcall(struct cache_detail *det= ail, struct cache_head *h) crq->buf =3D buf; crq->len =3D 0; crq->readers =3D 0; - spin_lock(&queue_lock); + spin_lock(&detail->queue_lock); if (test_bit(CACHE_PENDING, &h->flags)) { crq->item =3D cache_get(h); list_add_tail(&crq->q.list, &detail->queue); @@ -1259,7 +1258,7 @@ static int cache_pipe_upcall(struct cache_detail *det= ail, struct cache_head *h) } else /* Lost a race, no longer PENDING, so don't enqueue */ ret =3D -EAGAIN; - spin_unlock(&queue_lock); + spin_unlock(&detail->queue_lock); wake_up(&queue_wait); if (ret =3D=3D -EAGAIN) { kfree(buf); --=20 2.53.0