From patchwork Fri Apr 30 05:54:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12232349 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 38B09C43461 for ; Fri, 30 Apr 2021 05:55:00 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id DE9F761459 for ; Fri, 30 Apr 2021 05:54:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE9F761459 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8218E6B00AA; Fri, 30 Apr 2021 01:54:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7ABED6B00AB; Fri, 30 Apr 2021 01:54:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5D64B6B00AC; Fri, 30 Apr 2021 01:54:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0203.hostedemail.com [216.40.44.203]) by kanga.kvack.org (Postfix) with ESMTP id 3B3596B00AA for ; Fri, 30 Apr 2021 01:54:59 -0400 (EDT) Received: from smtpin12.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id F3017364C for ; Fri, 30 Apr 2021 05:54:58 +0000 (UTC) X-FDA: 78087969876.12.424564F Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf10.hostedemail.com (Postfix) with ESMTP id 5953840002E2 for ; Fri, 30 Apr 2021 05:54:47 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 9CC9F61459; Fri, 30 Apr 2021 05:54:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1619762097; bh=5XaufZwsmcZNa1E6vk0S1IkKNKXwDqnzLZBPcUnzkVw=; h=Date:From:To:Subject:In-Reply-To:From; b=h+eV4TiECq02OPUQ2i9G8S1RR/Kf0IcDO3og4J289DBw/pV3CEleu7JXzWNYRM0Dy vVFutAr0pC5nJ9570+648yLgok38SF+8z8LcfYz6/eAt+fsfdbd+4v6TSONpcAITJW tk9URQTjZqym6k04vWV8nPwDSPT4UA+XwKdf5hXk= Date: Thu, 29 Apr 2021 22:54:57 -0700 From: Andrew Morton To: akpm@linux-foundation.org, georgi.djakov@linaro.org, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, vbabka@suse.cz Subject: [patch 034/178] mm/page_owner: record the timestamp of all pages during free Message-ID: <20210430055457.HyvbZjCrD%akpm@linux-foundation.org> In-Reply-To: <20210429225251.02b6386d21b69255b4f6c163@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 5953840002E2 Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=h+eV4TiE; dmarc=none; spf=pass (imf10.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Stat-Signature: tdkowi1zo5z3fcafd8fr5phqj9fsfwdg Received-SPF: none (linux-foundation.org>: No applicable sender policy available) receiver=imf10; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619762087-499100 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: From: Georgi Djakov Subject: mm/page_owner: record the timestamp of all pages during free Collect the time when each allocation is freed, to help with memory analysis with kdump/ramdump. Add the timestamp also in the page_owner debugfs file and print it in dump_page(). Having another timestamp when we free the page helps for debugging page migration issues. For example both alloc and free timestamps being the same can gave hints that there is an issue with migrating memory, as opposed to a page just being dropped during migration. Link: https://lkml.kernel.org/r/20210203175905.12267-1-georgi.djakov@linaro.org Signed-off-by: Georgi Djakov Acked-by: Vlastimil Babka Signed-off-by: Andrew Morton --- Documentation/vm/page_owner.rst | 2 +- mm/page_owner.c | 12 ++++++++---- 2 files changed, 9 insertions(+), 5 deletions(-) --- a/Documentation/vm/page_owner.rst~mm-page_owner-record-the-timestamp-of-all-pages-during-free +++ a/Documentation/vm/page_owner.rst @@ -47,7 +47,7 @@ size change due to this facility. text data bss dec hex filename 48800 2445 644 51889 cab1 mm/page_alloc.o - 6574 108 29 6711 1a37 mm/page_owner.o + 6662 108 29 6799 1a8f mm/page_owner.o 1025 8 8 1041 411 mm/page_ext.o Although, roughly, 8 KB code is added in total, page_alloc.o increase by --- a/mm/page_owner.c~mm-page_owner-record-the-timestamp-of-all-pages-during-free +++ a/mm/page_owner.c @@ -27,6 +27,7 @@ struct page_owner { depot_stack_handle_t handle; depot_stack_handle_t free_handle; u64 ts_nsec; + u64 free_ts_nsec; pid_t pid; }; @@ -148,6 +149,7 @@ void __reset_page_owner(struct page *pag struct page_ext *page_ext; depot_stack_handle_t handle = 0; struct page_owner *page_owner; + u64 free_ts_nsec = local_clock(); handle = save_stack(GFP_NOWAIT | __GFP_NOWARN); @@ -158,6 +160,7 @@ void __reset_page_owner(struct page *pag __clear_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags); page_owner = get_page_owner(page_ext); page_owner->free_handle = handle; + page_owner->free_ts_nsec = free_ts_nsec; page_ext = page_ext_next(page_ext); } } @@ -243,6 +246,7 @@ void __copy_page_owner(struct page *oldp new_page_owner->handle = old_page_owner->handle; new_page_owner->pid = old_page_owner->pid; new_page_owner->ts_nsec = old_page_owner->ts_nsec; + new_page_owner->free_ts_nsec = old_page_owner->ts_nsec; /* * We don't clear the bit on the oldpage as it's going to be freed @@ -356,10 +360,10 @@ print_page_owner(char __user *buf, size_ return -ENOMEM; ret = snprintf(kbuf, count, - "Page allocated via order %u, mask %#x(%pGg), pid %d, ts %llu ns\n", + "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->ts_nsec, page_owner->free_ts_nsec); if (ret >= count) goto err; @@ -435,9 +439,9 @@ void __dump_page_owner(struct page *page else pr_alert("page_owner tracks the page as freed\n"); - pr_alert("page last allocated via order %u, migratetype %s, gfp_mask %#x(%pGg), pid %d, ts %llu\n", + pr_alert("page last allocated via order %u, migratetype %s, gfp_mask %#x(%pGg), pid %d, ts %llu, free_ts %llu\n", page_owner->order, migratetype_names[mt], gfp_mask, &gfp_mask, - page_owner->pid, page_owner->ts_nsec); + page_owner->pid, page_owner->ts_nsec, page_owner->free_ts_nsec); handle = READ_ONCE(page_owner->handle); if (!handle) {