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=-15.8 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_RED 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 EDA61C11F68 for ; Thu, 1 Jul 2021 01:52:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D262261480 for ; Thu, 1 Jul 2021 01:52:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238492AbhGABzN (ORCPT ); Wed, 30 Jun 2021 21:55:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:44820 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238416AbhGABzN (ORCPT ); Wed, 30 Jun 2021 21:55:13 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C06CD61241; Thu, 1 Jul 2021 01:52:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1625104364; bh=TFh44qdMZt9Vja3LMR2t+j58k4ehpx3rEYrJZb1pg1M=; h=Date:From:To:Subject:In-Reply-To:From; b=WW78ydZWlDXTQkA2PKxV4ffAyp3EMMsB3nX2jtYQjtzlaTqSfvolprwjmftNFIiHu PLuT6nkdDjhpNfybLT5GyP9xcBJ/5N8SBV3gY36CrLfpGhnou1BYvzHUVPlc2onqu8 qugndc9nJOHwgcNc9C6U6HdNW8E0o/QpgEBadVmY= Date: Wed, 30 Jun 2021 18:52:43 -0700 From: Andrew Morton To: akpm@linux-foundation.org, david@redhat.com, georgi.djakov@linaro.org, linux-mm@kvack.org, lmark@codeaurora.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 103/192] mm/memory_hotplug: rate limit page migration warnings Message-ID: <20210701015243.6hfM4X7tH%akpm@linux-foundation.org> In-Reply-To: <20210630184624.9ca1937310b0dd5ce66b30e7@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Liam Mark Subject: mm/memory_hotplug: rate limit page migration warnings When offlining memory the system can attempt to migrate a lot of pages, if there are problems with migration this can flood the logs. Printing all the data hogs the CPU and cause some RT threads to run for a long time, which may have some bad consequences. Rate limit the page migration warnings in order to avoid this. Link: https://lkml.kernel.org/r/20210505140542.24935-1-georgi.djakov@linaro.org Signed-off-by: Liam Mark Signed-off-by: Georgi Djakov Cc: David Hildenbrand Signed-off-by: Andrew Morton --- mm/memory_hotplug.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) --- a/mm/memory_hotplug.c~mm-memory_hotplug-rate-limit-page-migration-warnings +++ a/mm/memory_hotplug.c @@ -1406,6 +1406,8 @@ do_migrate_range(unsigned long start_pfn struct page *page, *head; int ret = 0; LIST_HEAD(source); + static DEFINE_RATELIMIT_STATE(migrate_rs, DEFAULT_RATELIMIT_INTERVAL, + DEFAULT_RATELIMIT_BURST); for (pfn = start_pfn; pfn < end_pfn; pfn++) { if (!pfn_valid(pfn)) @@ -1452,8 +1454,10 @@ do_migrate_range(unsigned long start_pfn page_is_file_lru(page)); } else { - pr_warn("failed to isolate pfn %lx\n", pfn); - dump_page(page, "isolation failed"); + if (__ratelimit(&migrate_rs)) { + pr_warn("failed to isolate pfn %lx\n", pfn); + dump_page(page, "isolation failed"); + } } put_page(page); } @@ -1482,9 +1486,11 @@ do_migrate_range(unsigned long start_pfn (unsigned long)&mtc, MIGRATE_SYNC, MR_MEMORY_HOTPLUG); if (ret) { list_for_each_entry(page, &source, lru) { - pr_warn("migrating pfn %lx failed ret:%d ", - page_to_pfn(page), ret); - dump_page(page, "migration failure"); + if (__ratelimit(&migrate_rs)) { + pr_warn("migrating pfn %lx failed ret:%d\n", + page_to_pfn(page), ret); + dump_page(page, "migration failure"); + } } putback_movable_pages(&source); } _