From patchwork Fri Jan 28 19:56:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Waiman Long X-Patchwork-Id: 12729012 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B020CC433FE for ; Fri, 28 Jan 2022 19:57:31 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 16AF66B00FE; Fri, 28 Jan 2022 14:57:31 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 119DE6B0102; Fri, 28 Jan 2022 14:57:31 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EFCA06B0106; Fri, 28 Jan 2022 14:57:30 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0170.hostedemail.com [216.40.44.170]) by kanga.kvack.org (Postfix) with ESMTP id DD7BC6B00FE for ; Fri, 28 Jan 2022 14:57:30 -0500 (EST) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 9D61118209A93 for ; Fri, 28 Jan 2022 19:57:30 +0000 (UTC) X-FDA: 79080755460.19.B40EDED Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf16.hostedemail.com (Postfix) with ESMTP id 3E816180002 for ; Fri, 28 Jan 2022 19:57:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643399849; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=z7PkS3p7o3c1KlQT9mE47JFulyDrby+E1xl/snWb8i0=; b=ZmdZqs0qj1/Nqe1eOgebpdN7IIG08owjDtRMU0p6RzzEj3zqsHl0ZJYgokLJLTUx5QLAHa djCL3agpOZ5JGXg5FfHgkFw9ZGR6sd1qEeanYtnvyTpnquVThnBu0ojENNWZwZohprABjY wVfaluFUYc00bq6QlAdud4l8nV+TG8g= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-463-iCC205RvNbe_8lZYT7eujw-1; Fri, 28 Jan 2022 14:57:26 -0500 X-MC-Unique: iCC205RvNbe_8lZYT7eujw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C9FE31083F6D; Fri, 28 Jan 2022 19:57:24 +0000 (UTC) Received: from llong.com (unknown [10.22.33.1]) by smtp.corp.redhat.com (Postfix) with ESMTP id D155C5DB82; Fri, 28 Jan 2022 19:57:23 +0000 (UTC) From: Waiman Long To: Johannes Weiner , Michal Hocko , Vladimir Davydov , Andrew Morton Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, Rafael Aquini , Waiman Long Subject: [PATCH 1/2] mm/page_owner: Introduce SNPRINTF() macro that includes length error check Date: Fri, 28 Jan 2022 14:56:41 -0500 Message-Id: <20220128195642.416743-2-longman@redhat.com> In-Reply-To: <20220128195642.416743-1-longman@redhat.com> References: <20220128195642.416743-1-longman@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Stat-Signature: rou6kyitf3npesmno3tzodbhhy4smc78 X-Rspam-User: nil Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=ZmdZqs0q; spf=none (imf16.hostedemail.com: domain of longman@redhat.com has no SPF policy when checking 170.10.129.124) smtp.mailfrom=longman@redhat.com; dmarc=pass (policy=none) header.from=redhat.com X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 3E816180002 X-HE-Tag: 1643399850-71403 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: In print_page_owner(), there is a repetitive check after each snprintf() to make sure that the final length is less than the buffer size. Simplify the code and make it easier to read by embedding the buffer length check and increment inside the macro. Signed-off-by: Waiman Long --- mm/page_owner.c | 50 +++++++++++++++++++++++-------------------------- 1 file changed, 23 insertions(+), 27 deletions(-) diff --git a/mm/page_owner.c b/mm/page_owner.c index 99e360df9465..c52ce9d6bc3b 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -325,12 +325,20 @@ void pagetypeinfo_showmixedcount_print(struct seq_file *m, seq_putc(m, '\n'); } +#define SNPRINTF(_buf, _size, _len, _err, _fmt, ...) \ + do { \ + _len += snprintf(_buf + _len, _size - _len, _fmt, \ + ##__VA_ARGS__); \ + if (_len >= _size) \ + goto _err; \ + } while (0) + static ssize_t print_page_owner(char __user *buf, size_t count, unsigned long pfn, struct page *page, struct page_owner *page_owner, depot_stack_handle_t handle) { - int ret, pageblock_mt, page_mt; + int ret = 0, pageblock_mt, page_mt; char *kbuf; count = min_t(size_t, count, PAGE_SIZE); @@ -338,44 +346,32 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn, if (!kbuf) return -ENOMEM; - ret = snprintf(kbuf, count, - "Page allocated via order %u, mask %#x(%pGg), pid %d, ts %llu ns, free_ts %llu ns\n", - page_owner->order, page_owner->gfp_mask, - &page_owner->gfp_mask, page_owner->pid, - page_owner->ts_nsec, page_owner->free_ts_nsec); - - if (ret >= count) - goto err; + SNPRINTF(kbuf, count, ret, err, + "Page allocated via order %u, mask %#x(%pGg), pid %d, ts %llu ns, free_ts %llu ns\n", + page_owner->order, page_owner->gfp_mask, + &page_owner->gfp_mask, page_owner->pid, + page_owner->ts_nsec, page_owner->free_ts_nsec); /* Print information relevant to grouping pages by mobility */ pageblock_mt = get_pageblock_migratetype(page); page_mt = gfp_migratetype(page_owner->gfp_mask); - ret += snprintf(kbuf + ret, count - ret, - "PFN %lu type %s Block %lu type %s Flags %pGp\n", - pfn, - migratetype_names[page_mt], - pfn >> pageblock_order, - migratetype_names[pageblock_mt], - &page->flags); - - if (ret >= count) - goto err; + SNPRINTF(kbuf, count, ret, err, + "PFN %lu type %s Block %lu type %s Flags %pGp\n", + pfn, migratetype_names[page_mt], + pfn >> pageblock_order, + migratetype_names[pageblock_mt], + &page->flags); ret += stack_depot_snprint(handle, kbuf + ret, count - ret, 0); if (ret >= count) goto err; - if (page_owner->last_migrate_reason != -1) { - ret += snprintf(kbuf + ret, count - ret, + if (page_owner->last_migrate_reason != -1) + SNPRINTF(kbuf, count, ret, err, "Page has been migrated, last migrate reason: %s\n", migrate_reason_names[page_owner->last_migrate_reason]); - if (ret >= count) - goto err; - } - ret += snprintf(kbuf + ret, count - ret, "\n"); - if (ret >= count) - goto err; + SNPRINTF(kbuf, count, ret, err, "\n"); if (copy_to_user(buf, kbuf, ret)) ret = -EFAULT; From patchwork Fri Jan 28 19:56:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Waiman Long X-Patchwork-Id: 12729014 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02789C433EF for ; Fri, 28 Jan 2022 19:57:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 402F36B0106; Fri, 28 Jan 2022 14:57:32 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 363A26B0108; Fri, 28 Jan 2022 14:57:32 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1DC176B0109; Fri, 28 Jan 2022 14:57:32 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0030.hostedemail.com [216.40.44.30]) by kanga.kvack.org (Postfix) with ESMTP id 0EFD96B0106 for ; Fri, 28 Jan 2022 14:57:32 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id C6BE79677C for ; Fri, 28 Jan 2022 19:57:31 +0000 (UTC) X-FDA: 79080755502.28.1170543 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf13.hostedemail.com (Postfix) with ESMTP id 79B3820005 for ; Fri, 28 Jan 2022 19:57:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643399850; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gRdxpfrhDzN5J2ZCp0or9HoZYV0jMrufVKuIP+ZP2Uo=; b=NrSV1O1bMsCk0Xs3VBRP/14hM8Ca4UMEazRNGuVAMr35xBxJawatRqkKm3q0DJonQSC3Ul KvEEZiWVSDNTN8CFavKo8NWH01UQsXVfHMU98NMFeurptzwCs2nHWzFeZoQpOi8PZJk1zF QsavSGTdj5yMIyTHQ5eD5DjF4PzeH4g= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-356-GCdYn6EWP_Oq0PMNqG-U-w-1; Fri, 28 Jan 2022 14:57:27 -0500 X-MC-Unique: GCdYn6EWP_Oq0PMNqG-U-w-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1D37A1083F68; Fri, 28 Jan 2022 19:57:26 +0000 (UTC) Received: from llong.com (unknown [10.22.33.1]) by smtp.corp.redhat.com (Postfix) with ESMTP id EFAE45DB82; Fri, 28 Jan 2022 19:57:24 +0000 (UTC) From: Waiman Long To: Johannes Weiner , Michal Hocko , Vladimir Davydov , Andrew Morton Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, Rafael Aquini , Waiman Long Subject: [PATCH 2/2] mm/page_owner: Dump memcg information Date: Fri, 28 Jan 2022 14:56:42 -0500 Message-Id: <20220128195642.416743-3-longman@redhat.com> In-Reply-To: <20220128195642.416743-1-longman@redhat.com> References: <20220128195642.416743-1-longman@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 79B3820005 X-Stat-Signature: rimipw6w9z3t63ghdm8r1fczkrqoeme4 X-Rspam-User: nil Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=NrSV1O1b; spf=none (imf13.hostedemail.com: domain of longman@redhat.com has no SPF policy when checking 170.10.133.124) smtp.mailfrom=longman@redhat.com; dmarc=pass (policy=none) header.from=redhat.com X-HE-Tag: 1643399851-869679 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: It was found that a number of offlined memcgs were not freed because they were pinned by some charged pages that were present. Even "echo 1 > /proc/sys/vm/drop_caches" wasn't able to free those pages. These offlined but not freed memcgs tend to increase in number over time with the side effect that percpu memory consumption as shown in /proc/meminfo also increases over time. In order to find out more information about those pages that pin offlined memcgs, the page_owner feature is extended to dump memory cgroup information especially whether the cgroup is offlined or not. Signed-off-by: Waiman Long --- mm/page_owner.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/mm/page_owner.c b/mm/page_owner.c index c52ce9d6bc3b..e5d8c642296b 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include "internal.h" @@ -339,6 +340,7 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn, depot_stack_handle_t handle) { int ret = 0, pageblock_mt, page_mt; + unsigned long __maybe_unused memcg_data; char *kbuf; count = min_t(size_t, count, PAGE_SIZE); @@ -371,6 +373,32 @@ print_page_owner(char __user *buf, size_t count, unsigned long pfn, "Page has been migrated, last migrate reason: %s\n", migrate_reason_names[page_owner->last_migrate_reason]); +#ifdef CONFIG_MEMCG + /* + * Look for memcg information and print it out + */ + memcg_data = READ_ONCE(page->memcg_data); + if (memcg_data) { + struct mem_cgroup *memcg = page_memcg_check(page); + bool onlined; + char name[80]; + + if (memcg_data & MEMCG_DATA_OBJCGS) + SNPRINTF(kbuf, count, ret, err, "Slab cache page\n"); + + if (!memcg) + goto copy_out; + + onlined = (memcg->css.flags & CSS_ONLINE); + cgroup_name(memcg->css.cgroup, name, sizeof(name) - 1); + SNPRINTF(kbuf, count, ret, err, "Charged %sto %smemcg %s\n", + PageMemcgKmem(page) ? "(via objcg) " : "", + onlined ? "" : "offlined ", name); + } + +copy_out: +#endif + SNPRINTF(kbuf, count, ret, err, "\n"); if (copy_to_user(buf, kbuf, ret))