From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 72D9C3B14BF; Fri, 19 Jun 2026 15:26:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781882817; cv=none; b=BHRm718m1nQguaZM7UdWW8I3KNwJOrEa7q802GL8w/RuwQPERRRic5J3zrnN/wIDBtNJJK5BQ6R4PF2vbTHRFDww0ic1yF000r2vxq3VWLjEAb+3tLRaEZzFakvfWsk/zZC8AAGlTHQrUiWhaA6xcQ4zki6kbhaQqqdjH/Rb35g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781882817; c=relaxed/simple; bh=AfWT6iqjZZ3/54U4I8X/Ze5Vcl/XKDZilQH90UOg2EE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=jlrgoxriBj+VeGCv9BvROuO58GQUFnwzHNwHhJjiuyWwMNTjwPMqNog+nwiCB7pKNm5GJDLdOnXWls/Dp2BRT2GtQVR1y1oSfNCspElmM/d1aqCKcWN3gHBrLotniC8YtP5/oIQoy+oz7Ftud25w14oQy2FABz8MyT53Xm/+Crg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=MLb3QSUj; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="MLb3QSUj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 68A061F000E9; Fri, 19 Jun 2026 15:26:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781882816; bh=SuOCWRILm4Nl8tZG3NYkifnjxP6I9ZIMSynOCGAkVb8=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=MLb3QSUjBZrVmgrIcScsSUAg9d7SEU5aqfojwzSgN2TSLHc92XqFRbITQhLobNJwh gm+sv4HRpBJLyH7//ahj6INQAhyfNIt00Df340zvvpEmM+XmxMJqcv9gwD8+1+xUHw TUnJur4YCMl8kEqmHrIhtR4v1yTl8DAc5A/RsojGslzrN+z6GJeJTt5hW8JW+Wr+9x uObHSTOYXIZF6zr6eeMTF9t0S0p6oSPG6w+b20cfLuy2n2f10Nfpoq3s+iwIFZ107f NWrOhY/c2g65iDM/mDvPN6N9qR4g6qGqPpQEVkCWtEyGyrkCOHTpBtL0W6Z8GZFjnV F+GsPgcAOwnEQ== From: Jeff Layton Date: Fri, 19 Jun 2026 11:26:40 -0400 Subject: [PATCH v6 5/6] nfsd: count NFSv4 callback operations per netns Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260619-exportd-netlink-v6-5-ddef3499793c@kernel.org> References: <20260619-exportd-netlink-v6-0-ddef3499793c@kernel.org> In-Reply-To: <20260619-exportd-netlink-v6-0-ddef3499793c@kernel.org> To: NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey , Chuck Lever Cc: Trond Myklebust , Anna Schumaker , Steve Dickson , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Jeff Layton X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=7380; i=jlayton@kernel.org; h=from:subject:message-id; bh=AfWT6iqjZZ3/54U4I8X/Ze5Vcl/XKDZilQH90UOg2EE=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBqNV+4U3wY6EDqhdHmPnReU5rs5fafY/zqGmczi ONUltCsjGCJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCajVfuAAKCRAADmhBGVaC FRqMD/kBpx8rPaOZQ7pbaMjQBc10bzUvgcculaPb5RYazExWSMETWU/mtapGeWR+fV0yzSWWtaE 01NCG3Wob6CnUN5G/ovfyDIw4V/b9Z9/wKNt20YCXKvXTGbNZITl954YIbbq5IiJOlcf3dtJOS1 Da2BtaCrpaCT0jfJ85X9WWSbFeI60IjI2eF6bFUsljh1/4rrX1FsYBu0h7G1CZA8pSARFcV0BWj rgXQFQbeZm6n8zfUGfZEYAKxgUYHTqOod7ows7OXMjUYGFxWXX6kjRPU9cuunHDpfr+xNHHnAso rjo/LRVRDG9PcNHeJGi67geicvJdDvI2Onn1ObTJaMsAJoGhq0N9rxqr38duIwN/X7t4x2ay3Gx dvcf/OZsfY8cjOnDCTYqOSXLTvDu5VlI+WyFz6GVPhZXq6K4JZDYUVNJj4gVRmM0TzlclKUxiXt IxGpdasSOsUaoDYpGMBlL10MoOoBejBpLIEK48S/2DH9a+4FMqy3qmgPRvWQg+NW/h1QNP36AAm Bs3UORhSVfKhnIWDWc0v8HLO61FIac8tT9lXpR7J2p2sgpENKSTiaf4H6LjVyRankWzGAUswt4o EwTZV9Dc8MiV95K13XUJ/b+csCPH6Karfqrlf79ofk9VeF0LTv7SAdZ7wrGgmkK6RKNteutZ4HM Imq7gAbfZnVStGw== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 The NFS server tracks per-operation call counts for the forward channel (proc4ops) but keeps no statistics for the NFSv4 backchannel (callback) operations it sends to clients. Add a per-netns array of percpu counters for callback operations, indexed by RFC 8881 callback opcode (OP_CB_GETATTR..OP_CB_OFFLOAD), and bump the relevant counter in nfsd4_run_cb(), which is hit exactly once per callback that is actually queued. CB_GETATTR is sent when a GETATTR conflicts with an outstanding write delegation, which is roughly what the dedicated wdeleg_getattr counter tracked. The two are not identical: the old counter incremented on every such conflict, whereas the CB_GETATTR counter only counts callbacks that are actually queued, so concurrent conflicts that coalesce onto an already in-flight CB_GETATTR are now counted once rather than once per conflict. Report the procfs "wdeleg_getattr" line from the CB_GETATTR counter and drop the now-redundant NFSD_STATS_WDELEG_GETATTR counter, its helper, and its increment site. Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton --- fs/nfsd/netns.h | 12 +++++++++++- fs/nfsd/nfs4callback.c | 22 +++++++++++++++++++++- fs/nfsd/nfs4state.c | 2 -- fs/nfsd/nfsctl.c | 14 ++++++++++++++ fs/nfsd/stats.c | 2 +- fs/nfsd/stats.h | 5 +++-- 6 files changed, 50 insertions(+), 7 deletions(-) diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h index 03724bef10a7..37daba0d4747 100644 --- a/fs/nfsd/netns.h +++ b/fs/nfsd/netns.h @@ -53,11 +53,16 @@ enum { NFSD_STATS_FIRST_NFS4_OP, /* count of individual nfsv4 operations */ NFSD_STATS_LAST_NFS4_OP = NFSD_STATS_FIRST_NFS4_OP + LAST_NFS4_OP, #define NFSD_STATS_NFS4_OP(op) (NFSD_STATS_FIRST_NFS4_OP + (op)) - NFSD_STATS_WDELEG_GETATTR, /* count of getattr conflict with wdeleg */ #endif NFSD_STATS_COUNTERS_NUM }; +/* + * Per-netns NFSv4 callback (backchannel) per-operation counters, indexed + * directly by RFC 8881 callback opcode (OP_CB_GETATTR..OP_CB_OFFLOAD). + */ +#define NFSD_STATS_CB_OPS_NUM (OP_CB_OFFLOAD + 1) + /* * Represents a nfsd "container". With respect to nfsv4 state tracking, the * fields of interest are the *_id_hashtbls and the *_name_tree. These track @@ -198,6 +203,11 @@ struct nfsd_net { /* Per-netns stats counters */ struct percpu_counter counter[NFSD_STATS_COUNTERS_NUM]; +#ifdef CONFIG_NFSD_V4 + /* Per-netns NFSv4 callback (backchannel) per-operation counters */ + struct percpu_counter cb_counter[NFSD_STATS_CB_OPS_NUM]; +#endif + /* sunrpc svc stats */ struct svc_stat nfsd_svcstats; diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c index 71dcb448fa0a..b171257da6ba 100644 --- a/fs/nfsd/nfs4callback.c +++ b/fs/nfsd/nfs4callback.c @@ -1921,12 +1921,32 @@ void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp, bool nfsd4_run_cb(struct nfsd4_callback *cb) { struct nfs4_client *clp = cb->cb_clp; + struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); + const struct nfsd4_callback_ops *ops = cb->cb_ops; + u32 minorversion = clp->cl_minorversion; bool queued; + /* + * Snapshot the opcode, minorversion, and the per-net pointer before + * queuing: once nfsd4_queue_cb() has queued the work, the callback (and + * the object that embeds it) may be processed and freed concurrently, so + * neither cb nor clp can be dereferenced afterward. + */ nfsd41_cb_inflight_begin(clp); queued = nfsd4_queue_cb(cb); - if (!queued) + if (queued) { + if (ops) + nfsd_stats_cb_op_inc(nn, ops->opcode); + /* + * Minorversion > 0 callbacks prepend a CB_SEQUENCE op (see + * encode_cb_sequence4args()); count it like the forechannel + * counts SEQUENCE, so it isn't perpetually reported as zero. + */ + if (minorversion > 0) + nfsd_stats_cb_op_inc(nn, OP_CB_SEQUENCE); + } else { nfsd41_cb_inflight_end(clp); + } return queued; } diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index b830aed7ae39..8f8da1312231 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -9904,7 +9904,6 @@ __be32 nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct dentry *dentry, struct nfs4_delegation **pdp) { - struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id); struct nfsd_thread_local_info *ntli = rqstp->rq_private; struct file_lock_context *ctx; struct nfs4_delegation *dp = NULL; @@ -9944,7 +9943,6 @@ nfsd4_deleg_getattr_conflict(struct svc_rqst *rqstp, struct dentry *dentry, return 0; } - nfsd_stats_wdeleg_getattr_inc(nn); refcount_inc(&dp->dl_stid.sc_count); ncf = &dp->dl_cb_fattr; nfs4_cb_getattr(&dp->dl_cb_fattr); diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index f0514d8149cd..4710415790e2 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -2691,6 +2691,13 @@ static __net_init int nfsd_net_init(struct net *net) if (retval) goto out_repcache_error; +#ifdef CONFIG_NFSD_V4 + retval = percpu_counter_init_many(nn->cb_counter, 0, GFP_KERNEL, + NFSD_STATS_CB_OPS_NUM); + if (retval) + goto out_cb_counter_error; +#endif + memset(&nn->nfsd_svcstats, 0, sizeof(nn->nfsd_svcstats)); nn->nfsd_svcstats.program = &nfsd_programs[0]; retval = svc_stat_alloc_counts(&nn->nfsd_svcstats); @@ -2719,6 +2726,10 @@ static __net_init int nfsd_net_init(struct net *net) out_svcstats_error: svc_stat_free_counts(&nn->nfsd_svcstats); out_proc_error: +#ifdef CONFIG_NFSD_V4 + percpu_counter_destroy_many(nn->cb_counter, NFSD_STATS_CB_OPS_NUM); +out_cb_counter_error: +#endif percpu_counter_destroy_many(nn->counter, NFSD_STATS_COUNTERS_NUM); out_repcache_error: nfsd_idmap_shutdown(net); @@ -2759,6 +2770,9 @@ static __net_exit void nfsd_net_exit(struct net *net) nfsd_net_cb_shutdown(nn); nfsd_proc_stat_shutdown(net); svc_stat_free_counts(&nn->nfsd_svcstats); +#ifdef CONFIG_NFSD_V4 + percpu_counter_destroy_many(nn->cb_counter, NFSD_STATS_CB_OPS_NUM); +#endif percpu_counter_destroy_many(nn->counter, NFSD_STATS_COUNTERS_NUM); nfsd_idmap_shutdown(net); nfsd_export_shutdown(net); diff --git a/fs/nfsd/stats.c b/fs/nfsd/stats.c index f7eaf95e20fc..35d9a5571946 100644 --- a/fs/nfsd/stats.c +++ b/fs/nfsd/stats.c @@ -63,7 +63,7 @@ static int nfsd_show(struct seq_file *seq, void *v) percpu_counter_sum_positive(&nn->counter[NFSD_STATS_NFS4_OP(i)])); } seq_printf(seq, "\nwdeleg_getattr %lld", - percpu_counter_sum_positive(&nn->counter[NFSD_STATS_WDELEG_GETATTR])); + percpu_counter_sum_positive(&nn->cb_counter[OP_CB_GETATTR])); seq_putc(seq, '\n'); #endif diff --git a/fs/nfsd/stats.h b/fs/nfsd/stats.h index e4efb0e4e56d..f90cd565f7cb 100644 --- a/fs/nfsd/stats.h +++ b/fs/nfsd/stats.h @@ -68,9 +68,10 @@ static inline void nfsd_stats_drc_mem_usage_sub(struct nfsd_net *nn, s64 amount) } #ifdef CONFIG_NFSD_V4 -static inline void nfsd_stats_wdeleg_getattr_inc(struct nfsd_net *nn) +static inline void nfsd_stats_cb_op_inc(struct nfsd_net *nn, u32 opcode) { - percpu_counter_inc(&nn->counter[NFSD_STATS_WDELEG_GETATTR]); + if (opcode >= OP_CB_GETATTR && opcode <= OP_CB_OFFLOAD) + percpu_counter_inc(&nn->cb_counter[opcode]); } #endif #endif /* _NFSD_STATS_H */ -- 2.54.0