From patchwork Thu May 9 20:43:23 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Meneghini X-Patchwork-Id: 13660402 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 BB9DE84A5F for ; Thu, 9 May 2024 20:43:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715287417; cv=none; b=pOZYPl4j7F/thoeqyCrHNLVanTVfjUEWpi0C3BA2alGbnzUsDivvSDUyv8lT6gbN5CGU9XI8AJ6k5hu8zGq7jktO8gxrVn9kXIkbWBxZqxGDa6ygFjQHpUAI/UhJKQAVYiCDtktFW8GTjeP0I0sVPfb6yvjRDHDhVMudEBHvXZE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715287417; c=relaxed/simple; bh=GdvpxFT42CDKwuUMF85vnf6gLm9iuggvRLM0H9Yu/RQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-type; b=Fqv7CD8xMomNKGJThNkDwkM9p1potTXgdMN/vf0jvINjTAosSAPI6VsE/CkJXLL9Jle4WavkPQmJywBQTTcwn4eQtxYYEf7m3xLsUor0rTlQGN3e29UycbO3V/FTypyd2DBApLOVrXw/PNYN60L/LLNWI9VcB8CzHDG8ok6R0MY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=SHWiNKF1; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="SHWiNKF1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1715287414; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bKx0S7FzwqaZ25i9u3aRmby5t1CJ8YR9Zqwq3RwKUt4=; b=SHWiNKF1rrHNGHDmuqfQgYe8khGfKGZ2o38mDnTlQv4DSiYoEbw2GqJ7bw+uXwvCinUDve V8TRtdhXoF0GabkAnIu5jKLrSkZ3j6RnwdF3+bdgFegQhDY4jB9kawlUcyKLaylN7m+KNr wa/8rj400U+U6eUqubslV4HafNfCbVk= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-119-oQ-iO5sKMVeULXi4UoE1Nw-1; Thu, 09 May 2024 16:43:29 -0400 X-MC-Unique: oQ-iO5sKMVeULXi4UoE1Nw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E3F3F800A03; Thu, 9 May 2024 20:43:28 +0000 (UTC) Received: from jmeneghi.bos.com (unknown [10.22.16.53]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3FBF61D69461; Thu, 9 May 2024 20:43:28 +0000 (UTC) From: John Meneghini To: tj@kernel.org, josef@toxicpanda.com, axboe@kernel.dk, kbusch@kernel.org, hch@lst.de, sagi@grimberg.me, emilne@redhat.com, hare@kernel.org Cc: linux-block@vger.kernel.org, cgroups@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, jmeneghi@redhat.com, jrani@purestorage.com, randyj@purestorage.com, aviv.coro@ibm.com Subject: [PATCH v3 2/3] nvme: add 'latency' iopolicy Date: Thu, 9 May 2024 16:43:23 -0400 Message-Id: <20240509204324.832846-3-jmeneghi@redhat.com> In-Reply-To: <20240403141756.88233-1-hare@kernel.org> References: <20240403141756.88233-1-hare@kernel.org> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 From: Hannes Reinecke Add a latency-based I/O policy for multipathing. It uses the blk-nodelat latency tracker to provide latencies for each node, and schedules I/O on the path with the least latency for the submitting node. Signed-off-by: Hannes Reinecke Make this compile when CONFIG_BLK_NODE_LATENCY is not set. Advertise the 'latency' iopolicy in modinfo. Signed-off-by: John Meneghini --- drivers/nvme/host/multipath.c | 63 ++++++++++++++++++++++++++++++----- drivers/nvme/host/nvme.h | 1 + 2 files changed, 55 insertions(+), 9 deletions(-) diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c index d916a5ddf5d4..e9330bb1990b 100644 --- a/drivers/nvme/host/multipath.c +++ b/drivers/nvme/host/multipath.c @@ -18,6 +18,7 @@ static const char *nvme_iopolicy_names[] = { [NVME_IOPOLICY_NUMA] = "numa", [NVME_IOPOLICY_RR] = "round-robin", [NVME_IOPOLICY_QD] = "queue-depth", + [NVME_IOPOLICY_LAT] = "latency", }; static int iopolicy = NVME_IOPOLICY_NUMA; @@ -32,6 +33,10 @@ static int nvme_set_iopolicy(const char *val, const struct kernel_param *kp) iopolicy = NVME_IOPOLICY_RR; else if (!strncmp(val, "queue-depth", 11)) iopolicy = NVME_IOPOLICY_QD; +#ifdef CONFIG_BLK_NODE_LATENCY + else if (!strncmp(val, "latency", 7)) + iopolicy = NVME_IOPOLICY_LAT; +#endif else return -EINVAL; @@ -43,10 +48,36 @@ static int nvme_get_iopolicy(char *buf, const struct kernel_param *kp) return sprintf(buf, "%s\n", nvme_iopolicy_names[iopolicy]); } +static int nvme_activate_iopolicy(struct nvme_subsystem *subsys, int iopolicy) +{ + struct nvme_ns_head *h; + struct nvme_ns *ns; + bool enable = iopolicy == NVME_IOPOLICY_LAT; + int ret = 0; + + mutex_lock(&subsys->lock); + list_for_each_entry(h, &subsys->nsheads, entry) { + list_for_each_entry_rcu(ns, &h->list, siblings) { + if (enable) { + ret = blk_nlat_enable(ns->disk); + if (ret) + break; + } else + blk_nlat_disable(ns->disk); + } + } + mutex_unlock(&subsys->lock); + return ret; +} + module_param_call(iopolicy, nvme_set_iopolicy, nvme_get_iopolicy, &iopolicy, 0644); MODULE_PARM_DESC(iopolicy, +#if defined(CONFIG_BLK_NODE_LATENCY) + "Default multipath I/O policy; 'numa' (default) , 'round-robin', 'queue-depth' or 'latency'"); +#else "Default multipath I/O policy; 'numa' (default) , 'round-robin' or 'queue-depth'"); +#endif void nvme_mpath_default_iopolicy(struct nvme_subsystem *subsys) { @@ -250,14 +281,16 @@ static struct nvme_ns *__nvme_find_path(struct nvme_ns_head *head, int node) { int found_distance = INT_MAX, fallback_distance = INT_MAX, distance; struct nvme_ns *found = NULL, *fallback = NULL, *ns; + int iopolicy = READ_ONCE(head->subsys->iopolicy); list_for_each_entry_rcu(ns, &head->list, siblings) { if (nvme_path_is_disabled(ns)) continue; - if (ns->ctrl->numa_node != NUMA_NO_NODE && - READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_NUMA) + if (iopolicy == NVME_IOPOLICY_NUMA) distance = node_distance(node, ns->ctrl->numa_node); + else if (iopolicy == NVME_IOPOLICY_LAT) + distance = blk_nlat_latency(ns->disk, node); else distance = LOCAL_DISTANCE; @@ -381,8 +414,8 @@ static inline bool nvme_path_is_optimized(struct nvme_ns *ns) inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head) { - int iopolicy = READ_ONCE(head->subsys->iopolicy); int node; + int iopolicy = READ_ONCE(head->subsys->iopolicy); struct nvme_ns *ns; /* @@ -401,8 +434,8 @@ inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head) if (iopolicy == NVME_IOPOLICY_RR) return nvme_round_robin_path(head, node, ns); - - if (unlikely(!nvme_path_is_optimized(ns))) + if (iopolicy == NVME_IOPOLICY_LAT || + unlikely(!nvme_path_is_optimized(ns))) return __nvme_find_path(head, node); return ns; } @@ -872,15 +905,18 @@ static ssize_t nvme_subsys_iopolicy_store(struct device *dev, { struct nvme_subsystem *subsys = container_of(dev, struct nvme_subsystem, dev); - int i; + int i, ret; for (i = 0; i < ARRAY_SIZE(nvme_iopolicy_names); i++) { if (sysfs_streq(buf, nvme_iopolicy_names[i])) { - nvme_subsys_iopolicy_update(subsys, i); - return count; + ret = nvme_activate_iopolicy(subsys, i); + if (!ret) { + nvme_subsys_iopolicy_update(subsys, i); + return count; + } + return ret; } } - return -EINVAL; } SUBSYS_ATTR_RW(iopolicy, S_IRUGO | S_IWUSR, @@ -916,6 +952,15 @@ static int nvme_lookup_ana_group_desc(struct nvme_ctrl *ctrl, void nvme_mpath_add_disk(struct nvme_ns *ns, __le32 anagrpid) { + if (!blk_nlat_init(ns->disk) && + READ_ONCE(ns->head->subsys->iopolicy) == NVME_IOPOLICY_LAT) { + int ret = blk_nlat_enable(ns->disk); + + if (unlikely(ret)) + pr_warn("%s: Failed to enable latency tracking, error %d\n", + ns->disk->disk_name, ret); + } + if (nvme_ctrl_use_ana(ns->ctrl)) { struct nvme_ana_group_desc desc = { .grpid = anagrpid, diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index a557b4577c01..66bf003a6c48 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -411,6 +411,7 @@ enum nvme_iopolicy { NVME_IOPOLICY_NUMA, NVME_IOPOLICY_RR, NVME_IOPOLICY_QD, + NVME_IOPOLICY_LAT, }; struct nvme_subsystem {