From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_MED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C548FC6778A for ; Tue, 3 Jul 2018 15:15:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6FF4D208E4 for ; Tue, 3 Jul 2018 15:15:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=toxicpanda-com.20150623.gappssmtp.com header.i=@toxicpanda-com.20150623.gappssmtp.com header.b="UkVtTGQj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6FF4D208E4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=toxicpanda.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934046AbeGCPPO (ORCPT ); Tue, 3 Jul 2018 11:15:14 -0400 Received: from mail-qk0-f195.google.com ([209.85.220.195]:37695 "EHLO mail-qk0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933329AbeGCPPL (ORCPT ); Tue, 3 Jul 2018 11:15:11 -0400 Received: by mail-qk0-f195.google.com with SMTP id t79-v6so1173548qke.4 for ; Tue, 03 Jul 2018 08:15:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=zRqF4UPWwilUKnhGI+by9p/CeiYxnq4DlF5TaiWOPMc=; b=UkVtTGQjGh0UGHC11cd6XZNd2cSpTNjlGp0LXggaOz5EuE4qB/aZ9uuq+ut/3NOu6S P8ryY2SW2GlwFhlBVqpgjP91Md3j5W4TFawlbK9XfBubB0SvkMAA4DrLylabJH4LmFFv y0Hny8+RGMx1VxpZZ3nJptKB9zjOICRgvHBeGJ4MW/UewrpFJw5O4OSFOoTFUdWgIoyk dP8DY6SqpLAlNLtA5DY5GzVNpCmw+hwSc5cTufVTs6+7T1PIQjGCM4MOOuYsFCfCAE88 3UjEmYYUiSKKsNUIClkTTp1zlIocbSsbJuv/FOgVo8kxhwimr5Urjpt8iqsu8SVzGM9z gvUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=zRqF4UPWwilUKnhGI+by9p/CeiYxnq4DlF5TaiWOPMc=; b=fgxzaunzZydt9JocAQklQwXG8X7+KHK46vADh3D6bGaaIrVGLgXr5rHHHFzaBYbvly 83zvSttFcD6KCDlFZ6/vzL9sMxsW+Aqp6LkFNsSEee+aOai1NTlF88dGVnzNgxZX5EGz SxZM3PhjXQ2skqnPcSj99Q+SgPp/VwP7s4fguamcAtIITBZGzXZkYxI97hkJGqGW0aP9 Szf1Ibqm2Px+4vYnCWbMqhjlmNr+tCaJB5KS/0fkkUVxwZ/ri3MSOjl/v673+QiBjcjc khNOGUQj6FORE7OMurZcJBnFi8lQiM3JUHt8zCeM1tQVKpUNT3927nx2tvwVjAhZEWRQ d00w== X-Gm-Message-State: APt69E3/k7ORo6A0vvKUEBUndWGaEu6ajmNJc87QwYyuZVfcH4xu2hbJ eDG+i+9WNpol2Ws24Gznm4jCcw== X-Google-Smtp-Source: AAOMgpe4YZKLle31UKewz0OK3GNDQIaljHPgVp5J4f/nyaa2wKbTsxdgAkJFWqaA/fn00/zuYR/tQg== X-Received: by 2002:a37:f44:: with SMTP id z65-v6mr25574581qkg.93.1530630910770; Tue, 03 Jul 2018 08:15:10 -0700 (PDT) Received: from localhost ([107.15.81.208]) by smtp.gmail.com with ESMTPSA id h44-v6sm948612qta.74.2018.07.03.08.15.09 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 03 Jul 2018 08:15:10 -0700 (PDT) From: Josef Bacik To: axboe@kernel.dk, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, hannes@cmpxchg.org, tj@kernel.org, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, kernel-team@fb.com Cc: Josef Bacik Subject: [PATCH 03/14] blk-cgroup: allow controllers to output their own stats Date: Tue, 3 Jul 2018 11:14:52 -0400 Message-Id: <20180703151503.2549-4-josef@toxicpanda.com> X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180703151503.2549-1-josef@toxicpanda.com> References: <20180703151503.2549-1-josef@toxicpanda.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Josef Bacik blk-iolatency has a few stats that it would like to print out, and instead of adding a bunch of crap to the generic code just provide a helper so that controllers can add stuff to the stat line if they want to. Hide it behind a boot option since it changes the output of io.stat from normal, and these stats are only interesting to developers. Signed-off-by: Josef Bacik Acked-by: Tejun Heo --- block/blk-cgroup.c | 47 +++++++++++++++++++++++++++++++++++++++++++--- include/linux/blk-cgroup.h | 3 +++ 2 files changed, 47 insertions(+), 3 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index eb85cb87c40f..7dc6f05cc44b 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -50,6 +50,8 @@ static struct blkcg_policy *blkcg_policy[BLKCG_MAX_POLS]; static LIST_HEAD(all_blkcgs); /* protected by blkcg_pol_mutex */ +static bool blkcg_debug_stats = false; + static bool blkcg_policy_enabled(struct request_queue *q, const struct blkcg_policy *pol) { @@ -954,13 +956,25 @@ static int blkcg_print_stat(struct seq_file *sf, void *v) hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) { const char *dname; + char *buf; struct blkg_rwstat rwstat; u64 rbytes, wbytes, rios, wios; + size_t size = seq_get_buf(sf, &buf), off = 0; + int i; + bool has_stats = false; dname = blkg_dev_name(blkg); if (!dname) continue; + /* + * Hooray string manipulation, count is the size written NOT + * INCLUDING THE \0, so size is now count+1 less than what we + * had before, but we want to start writing the next bit from + * the \0 so we only add count to buf. + */ + off += scnprintf(buf+off, size-off, "%s ", dname); + spin_lock_irq(blkg->q->queue_lock); rwstat = blkg_rwstat_recursive_sum(blkg, NULL, @@ -975,9 +989,33 @@ static int blkcg_print_stat(struct seq_file *sf, void *v) spin_unlock_irq(blkg->q->queue_lock); - if (rbytes || wbytes || rios || wios) - seq_printf(sf, "%s rbytes=%llu wbytes=%llu rios=%llu wios=%llu\n", - dname, rbytes, wbytes, rios, wios); + if (rbytes || wbytes || rios || wios) { + has_stats = true; + off += scnprintf(buf+off, size-off, + "rbytes=%llu wbytes=%llu rios=%llu wios=%llu", + rbytes, wbytes, rios, wios); + } + + if (!blkcg_debug_stats) + goto next; + + for (i = 0; i < BLKCG_MAX_POLS; i++) { + struct blkcg_policy *pol = blkcg_policy[i]; + size_t written; + + if (!blkg->pd[i] || !pol->pd_stat_fn) + continue; + + written = pol->pd_stat_fn(blkg->pd[i], buf+off, size-off); + if (written) + has_stats = true; + off += written; + } +next: + if (has_stats) { + off += scnprintf(buf+off, size-off, "\n"); + seq_commit(sf, off); + } } rcu_read_unlock(); @@ -1547,3 +1585,6 @@ void blkcg_policy_unregister(struct blkcg_policy *pol) mutex_unlock(&blkcg_pol_register_mutex); } EXPORT_SYMBOL_GPL(blkcg_policy_unregister); + +module_param(blkcg_debug_stats, bool, 0644); +MODULE_PARM_DESC(blkcg_debug_stats, "True if you want debug stats, false if not"); diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 69aa71dc0c04..b41292726c0f 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -148,6 +148,8 @@ typedef void (blkcg_pol_online_pd_fn)(struct blkg_policy_data *pd); typedef void (blkcg_pol_offline_pd_fn)(struct blkg_policy_data *pd); typedef void (blkcg_pol_free_pd_fn)(struct blkg_policy_data *pd); typedef void (blkcg_pol_reset_pd_stats_fn)(struct blkg_policy_data *pd); +typedef size_t (blkcg_pol_stat_pd_fn)(struct blkg_policy_data *pd, char *buf, + size_t size); struct blkcg_policy { int plid; @@ -167,6 +169,7 @@ struct blkcg_policy { blkcg_pol_offline_pd_fn *pd_offline_fn; blkcg_pol_free_pd_fn *pd_free_fn; blkcg_pol_reset_pd_stats_fn *pd_reset_stats_fn; + blkcg_pol_stat_pd_fn *pd_stat_fn; }; extern struct blkcg blkcg_root; -- 2.14.3