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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=no 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 1B721C433E0 for ; Wed, 3 Jun 2020 22:58:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id CB72F208C9 for ; Wed, 3 Jun 2020 22:58:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="p61efe7M" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CB72F208C9 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 753B5280025; Wed, 3 Jun 2020 18:58:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 72A81280003; Wed, 3 Jun 2020 18:58:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 63F1C280025; Wed, 3 Jun 2020 18:58:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0190.hostedemail.com [216.40.44.190]) by kanga.kvack.org (Postfix) with ESMTP id 46057280003 for ; Wed, 3 Jun 2020 18:58:32 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 06C39180AD804 for ; Wed, 3 Jun 2020 22:58:32 +0000 (UTC) X-FDA: 76889416464.10.apple55_103aa63634c12 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin10.hostedemail.com (Postfix) with ESMTP id DBE9616A62D for ; Wed, 3 Jun 2020 22:58:31 +0000 (UTC) X-HE-Tag: apple55_103aa63634c12 X-Filterd-Recvd-Size: 5816 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf09.hostedemail.com (Postfix) with ESMTP for ; Wed, 3 Jun 2020 22:58:31 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5D4F1208E4; Wed, 3 Jun 2020 22:58:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591225110; bh=iMR9mohRBQuwjLFwz6kUhWEH6tZAi2qLi1qqunIMIHQ=; h=Date:From:To:Subject:In-Reply-To:From; b=p61efe7MjfHjZ3B6s8moYzwn7p3CaUi/TCBaaZmKp74V033hfG+oUT7lsGCeigvuI 9GseJ7jUoSiS7+PosAk0tcg/rYqjByh/2XTn6h0glf6pPSDHvBwpfgf+LlXIcrL+jX 7pWP+u+GRqwLNa9yWyYBdGmpd00AeSmO9fWsSL6o= Date: Wed, 03 Jun 2020 15:58:29 -0700 From: Andrew Morton To: akpm@linux-foundation.org, anshuman.khandual@arm.com, david@redhat.com, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, richard.weiyang@gmail.com, rientjes@google.com, torvalds@linux-foundation.org Subject: [patch 033/131] mm/page_alloc.c: bad_flags is not necessary for bad_page() Message-ID: <20200603225829.1qsxpkO9U%akpm@linux-foundation.org> In-Reply-To: <20200603155549.e041363450869eaae4c7f05b@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: DBE9616A62D X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 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: Wei Yang Subject: mm/page_alloc.c: bad_flags is not necessary for bad_page() After commit 5b57b8f22709 ("mm/debug.c: always print flags in dump_page()"), page->flags is always printed for a bad page. It is not necessary to have bad_flags any more. Link: http://lkml.kernel.org/r/20200411220357.9636-3-richard.weiyang@gmail.com Signed-off-by: Wei Yang Suggested-by: Anshuman Khandual Cc: David Hildenbrand Cc: David Rientjes Cc: Michal Hocko Signed-off-by: Andrew Morton --- mm/page_alloc.c | 34 ++++++++++------------------------ 1 file changed, 10 insertions(+), 24 deletions(-) --- a/mm/page_alloc.c~mm-page_allocc-bad_flags-is-not-necessary-for-bad_page +++ a/mm/page_alloc.c @@ -607,8 +607,7 @@ static inline int __maybe_unused bad_ran } #endif -static void bad_page(struct page *page, const char *reason, - unsigned long bad_flags) +static void bad_page(struct page *page, const char *reason) { static unsigned long resume; static unsigned long nr_shown; @@ -637,10 +636,6 @@ static void bad_page(struct page *page, pr_alert("BUG: Bad page state in process %s pfn:%05lx\n", current->comm, page_to_pfn(page)); __dump_page(page, reason); - bad_flags &= page->flags; - if (bad_flags) - pr_alert("bad because of flags: %#lx(%pGp)\n", - bad_flags, &bad_flags); dump_page_owner(page); print_modules(); @@ -1077,11 +1072,7 @@ static inline bool page_expected_state(s static void free_pages_check_bad(struct page *page) { - const char *bad_reason; - unsigned long bad_flags; - - bad_reason = NULL; - bad_flags = 0; + const char *bad_reason = NULL; if (unlikely(atomic_read(&page->_mapcount) != -1)) bad_reason = "nonzero mapcount"; @@ -1089,15 +1080,13 @@ static void free_pages_check_bad(struct bad_reason = "non-NULL mapping"; if (unlikely(page_ref_count(page) != 0)) bad_reason = "nonzero _refcount"; - if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_FREE)) { + if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_FREE)) bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set"; - bad_flags = PAGE_FLAGS_CHECK_AT_FREE; - } #ifdef CONFIG_MEMCG if (unlikely(page->mem_cgroup)) bad_reason = "page still charged to cgroup"; #endif - bad_page(page, bad_reason, bad_flags); + bad_page(page, bad_reason); } static inline int free_pages_check(struct page *page) @@ -1128,7 +1117,7 @@ static int free_tail_pages_check(struct case 1: /* the first tail page: ->mapping may be compound_mapcount() */ if (unlikely(compound_mapcount(page))) { - bad_page(page, "nonzero compound_mapcount", 0); + bad_page(page, "nonzero compound_mapcount"); goto out; } break; @@ -1140,17 +1129,17 @@ static int free_tail_pages_check(struct break; default: if (page->mapping != TAIL_MAPPING) { - bad_page(page, "corrupted mapping in tail page", 0); + bad_page(page, "corrupted mapping in tail page"); goto out; } break; } if (unlikely(!PageTail(page))) { - bad_page(page, "PageTail not set", 0); + bad_page(page, "PageTail not set"); goto out; } if (unlikely(compound_head(page) != head_page)) { - bad_page(page, "compound_head not consistent", 0); + bad_page(page, "compound_head not consistent"); goto out; } ret = 0; @@ -2095,7 +2084,6 @@ static inline void expand(struct zone *z static void check_new_page_bad(struct page *page) { const char *bad_reason = NULL; - unsigned long bad_flags = 0; if (unlikely(page->flags & __PG_HWPOISON)) { /* Don't complain about hwpoisoned pages */ @@ -2108,15 +2096,13 @@ static void check_new_page_bad(struct pa bad_reason = "non-NULL mapping"; if (unlikely(page_ref_count(page) != 0)) bad_reason = "nonzero _refcount"; - if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_PREP)) { + if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_PREP)) bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag set"; - bad_flags = PAGE_FLAGS_CHECK_AT_PREP; - } #ifdef CONFIG_MEMCG if (unlikely(page->mem_cgroup)) bad_reason = "page still charged to cgroup"; #endif - bad_page(page, bad_reason, bad_flags); + bad_page(page, bad_reason); } /* _