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 3BA29483BFC for ; Wed, 26 Aug 2026 20:27:08 +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=1787776031; cv=none; b=WF6z2ya6qGTLlJybMu8TUsGgS8Te1gRiyfMZQGtTO9WFP3K2N8V1UpUJ6mx+Lf9xH5CxNebBMrZ0Ps0zc7DawY8qGzp6r3cskEkVc2SaXx32C4/VHWwszih/i7v+vbqGZuy6ttIsBGvhZ7Q5Rw6CvlRSCzbJ7/guPO85Tb51Vc8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787776031; c=relaxed/simple; bh=UCrkwucRTt37vOQ+X53rhjiRRwEA8Ly58dJbUhbjDZg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Dp1vJsJ0P/SuQuZ2Mj3y1OKt3X8kHnDOV+dZSByVmnUJ3I4xmOGvCeU/uasjim6xe7WGpkTjNObcHQzmDSjOw9QqxQRyUheSfBFhjsds6M8pUKbY/6rMvVWYnkx1V4XwHWBWRW/I7fwJHBWCcd8NHOy2Q27oM5BgzDxRaJ7FLD4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Sq03GgOK; 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="Sq03GgOK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED7391F00A3F; Wed, 26 Aug 2026 20:27:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787776028; bh=gok/pIU7vIVYoaJLq0wu1LIiPcziNcqxWMMHmw0+gnE=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=Sq03GgOKI3m5jrfJDkHYZk4y/avOuhLU5+XxOXlJZ0hpha5+Q5ARYemx3/8g4w4EG Y7fC4nQz+UTToImsJXaWblDS57HTAtt9gAB8IWQKW1TaoLaqHPN505wuv78v5eKVG4 1PyfL7fBN1pGtNGetdSw53/CEdzucAFDNuhf5f+GulG9Qo7qSDixzdkc9lhaN7XaFU 6Px3mu9b1gtW4hY95ZhXFEo7kVwPvGZdbZIGkFxsWealIWMk6QLRQJIKguabsmTFvI iKH55T+vlCpymA9qvIt+pTG+PdH+Z38wXYLHfztuwGFFWOlmbt/WrShJCaypqRt5nl bTkaaaXYPM+PQ== From: Chuck Lever Date: Wed, 26 Aug 2026 16:26:57 -0400 Subject: [PATCH 7/7] NFSD: Record DRC population in lookup tracepoints 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: <20260826-duplicate-reply-cache-v1-7-b1d51e1af5c7@kernel.org> References: <20260826-duplicate-reply-cache-v1-0-b1d51e1af5c7@kernel.org> In-Reply-To: <20260826-duplicate-reply-cache-v1-0-b1d51e1af5c7@kernel.org> To: Jeff Layton , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey Cc: Rick Macklem , linux-nfs@vger.kernel.org, Chuck Lever X-Mailer: b4 0.16-dev-da966 X-Developer-Signature: v=1; a=openpgp-sha256; l=2121; i=cel@kernel.org; h=from:subject:message-id; bh=UCrkwucRTt37vOQ+X53rhjiRRwEA8Ly58dJbUhbjDZg=; b=owEBbQKS/ZANAwAKATNqszNvZn+XAcsmYgBqj0wWxzMjk793FJDZI1FG7hy813M6Kc5sX98jR sFo+69T41OJAjMEAAEKAB0WIQQosuWwEobfJDzyPv4zarMzb2Z/lwUCao9MFgAKCRAzarMzb2Z/ l3tbD/wIvLx1Z7qHudQRKyq+p41mFLeRJv6hzJgSaaGUmKWzgGK5MlMZ3OuZ2mPzyoVNVByRPjk ZGZ3vhqC+zpSmHfB8Rv2vxFa/XH+j0WMRForqwU+V0wJNZhpCCfEWznWykNSz7nPi9Lhc5NqwDg XiiEmcZ36yH6KEaDaW4Gs89fquQu9nQxBxZAoK5Y5iPNMP5V89mMJKJsg6Bn9D5R4CO9AM2f5p6 setMGeE42hZZYU4t0OrSctzmVjkRzVJPrGTgisOTxkLzwMQUpH9VFQD3jt28p45b9ltKtNptvMK pkPBCrv1VKtgZ7dgiBWVv7FWjXRgIrhDHBHGJcp1h+XD2CqP3cVFsPmhTJOklHE9qLBZuf6TxOS deYY5cRrj72rRD/Bh/2k27mSitfchAlyjc3Iort+TM3IYR0tpwzXLonF8RqU4lr4Mvc4qQGJxUU vaCj2HjOLOjiMmji5wPXkMmEeoRAm5zSb6Vla14Y9kW0DM0fNaK3QW97izzGbd5kGpel/wH6Gmz rMVGyOVj65MOBvjObSJlWZWiKtJnr8FJe7gCN2N4P/UKHjBsyuXaxqoc+efTRBh5rAkwHxIZLMK XvOu6pILhgC++3K5CrKwYoVP9pfBiuukUnOJLuNnLJq7KhXv2IxUE7ozF3Ne6SWVP4MVKVXfoZN IZD169nN1wyVkKw== X-Developer-Key: i=cel@kernel.org; a=openpgp; fpr=28B2E5B01286DF243CF23EFE336AB3336F667F97 nfsd_drc_found reports the outcome of a lookup but not how full the cache was at the time, so a trace cannot show whether a miss happened under pressure. Add an entries= field. The count is passed as an explicit argument rather than read from nn->num_drc_entries in TP_fast_assign, so that per-connection lookup paths can later supply their own depth without changing the tracepoint format. Signed-off-by: Chuck Lever --- fs/nfsd/nfscache.c | 3 ++- fs/nfsd/trace.h | 11 +++++++---- 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c index dfbcc75fbb12..b917af667a89 100644 --- a/fs/nfsd/nfscache.c +++ b/fs/nfsd/nfscache.c @@ -606,7 +606,8 @@ int nfsd_cache_lookup(struct svc_rqst *rqstp, unsigned int start, } out_trace: - trace_nfsd_drc_found(nn, rqstp, rtn); + trace_nfsd_drc_found(nn, atomic_read(&nn->num_drc_entries), + rqstp, rtn); out_unlock: spin_unlock(&b->cache_lock); out: diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h index f1d399b3e51c..75b1d828f2e0 100644 --- a/fs/nfsd/trace.h +++ b/fs/nfsd/trace.h @@ -1500,23 +1500,26 @@ TRACE_DEFINE_ENUM(RC_DOIT); TRACE_EVENT(nfsd_drc_found, TP_PROTO( const struct nfsd_net *nn, + unsigned int num_drc_entries, const struct svc_rqst *rqstp, int result ), - TP_ARGS(nn, rqstp, result), + TP_ARGS(nn, num_drc_entries, rqstp, result), TP_STRUCT__entry( __field(unsigned long long, boot_time) + __field(unsigned int, num_drc_entries) __field(unsigned long, result) __field(u32, xid) ), TP_fast_assign( __entry->boot_time = nn->boot_time; + __entry->num_drc_entries = num_drc_entries; __entry->result = result; __entry->xid = be32_to_cpu(rqstp->rq_xid); ), - TP_printk("boot_time=%16llx xid=0x%08x result=%s", - __entry->boot_time, __entry->xid, - show_drc_retval(__entry->result)) + TP_printk("boot_time=%16llx entries=%u xid=0x%08x result=%s", + __entry->boot_time, __entry->num_drc_entries, + __entry->xid, show_drc_retval(__entry->result)) ); -- 2.55.0