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=-13.6 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, USER_AGENT_SANE_1 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 7D9C7C433E6 for ; Tue, 1 Sep 2020 06:31:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6430C2087D for ; Tue, 1 Sep 2020 06:31:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726377AbgIAGa7 (ORCPT ); Tue, 1 Sep 2020 02:30:59 -0400 Received: from out30-132.freemail.mail.aliyun.com ([115.124.30.132]:50413 "EHLO out30-132.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726050AbgIAGa6 (ORCPT ); Tue, 1 Sep 2020 02:30:58 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R421e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04400;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=9;SR=0;TI=SMTPD_---0U7VD5SL_1598941853; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U7VD5SL_1598941853) by smtp.aliyun-inc.com(127.0.0.1); Tue, 01 Sep 2020 14:30:53 +0800 Subject: Re: [PATCH v3 3/3] mm/armv6: work around armv6 cmpxchg support issue From: Alex Shi To: Anshuman Khandual , David Hildenbrand , Matthew Wilcox Cc: Andrew Morton , Baolin Wang , Russell King , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <1598928612-68996-1-git-send-email-alex.shi@linux.alibaba.com> <1598928612-68996-3-git-send-email-alex.shi@linux.alibaba.com> Message-ID: Date: Tue, 1 Sep 2020 14:30:51 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <1598928612-68996-3-git-send-email-alex.shi@linux.alibaba.com> Content-Type: text/plain; charset=gbk Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org seems there are couples archs can not do cmpxchg1 So update the patch here. And it's easy to fix if more arch issue find here. >From cdf98ae7b5e83bb7210c927d4749f62fee4ed115 Mon Sep 17 00:00:00 2001 From: Alex Shi Date: Mon, 31 Aug 2020 15:41:20 +0800 Subject: [PATCH v4 3/3] mm/pageblock: work around multiple arch's cmpxchg support issue Armv6, sh2, sparc32 and xtensa can not do cmpxchg1, so we have to use cmpxchg4 on it. arm-linux-gnueabi-ld: mm/page_alloc.o: in function `set_pfnblock_flags_mask': (.text+0x32b4): undefined reference to `__bad_cmpxchg' arm-linux-gnueabi-ld: (.text+0x32e0): undefined reference to `__bad_cmpxchg' Reported-by: kernel test robot Signed-off-by: Alex Shi Cc: Andrew Morton Cc: Baolin Wang Cc: Russell King Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org --- include/linux/mmzone.h | 20 +++++++++++++++++--- mm/page_alloc.c | 24 ++++++++++++------------ 2 files changed, 29 insertions(+), 15 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index be676e659fb7..364b29ed99b3 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -406,6 +406,20 @@ enum zone_type { #ifndef __GENERATING_BOUNDS_H +/* + * cmpxchg only support 32-bits operands on the following archs ARMv6, SPARC32 + * sh2, XTENSA. + */ +#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_SH2) || \ + defined(CONFIG_SPARC32) || defined(CONFIG_XTENSA) + +#define BITS_PER_FLAGS BITS_PER_LONG +typedef unsigned long pageblockflags_t; +#else +#define BITS_PER_FLAGS BITS_PER_BYTE +typedef unsigned char pageblockflags_t; +#endif + struct zone { /* Read-mostly fields */ @@ -437,7 +451,7 @@ struct zone { * Flags for a pageblock_nr_pages block. See pageblock-flags.h. * In SPARSEMEM, this map is stored in struct mem_section */ - unsigned char *pageblock_flags; + pageblockflags_t *pageblock_flags; #endif /* CONFIG_SPARSEMEM */ /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */ @@ -1159,7 +1173,7 @@ struct mem_section_usage { DECLARE_BITMAP(subsection_map, SUBSECTIONS_PER_SECTION); #endif /* See declaration of similar field in struct zone */ - unsigned char pageblock_flags[0]; + pageblockflags_t pageblock_flags[0]; }; void subsection_map_init(unsigned long pfn, unsigned long nr_pages); @@ -1212,7 +1226,7 @@ struct mem_section { extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]; #endif -static inline unsigned char *section_to_usemap(struct mem_section *ms) +static inline pageblockflags_t *section_to_usemap(struct mem_section *ms) { return ms->usage->pageblock_flags; } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 60342e764090..9a41c5dc78eb 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -445,7 +445,7 @@ static inline bool defer_init(int nid, unsigned long pfn, unsigned long end_pfn) #endif /* Return a pointer to the bitmap storing bits affecting a block of pages */ -static inline unsigned char *get_pageblock_bitmap(struct page *page, +static inline pageblockflags_t *get_pageblock_bitmap(struct page *page, unsigned long pfn) { #ifdef CONFIG_SPARSEMEM @@ -474,24 +474,24 @@ static inline int pfn_to_bitidx(struct page *page, unsigned long pfn) * Return: pageblock_bits flags */ static __always_inline -unsigned char __get_pfnblock_flags_mask(struct page *page, +pageblockflags_t __get_pfnblock_flags_mask(struct page *page, unsigned long pfn, unsigned long mask) { - unsigned char *bitmap; + pageblockflags_t *bitmap; unsigned long bitidx, byte_bitidx; - unsigned char byte; + pageblockflags_t byte; bitmap = get_pageblock_bitmap(page, pfn); bitidx = pfn_to_bitidx(page, pfn); - byte_bitidx = bitidx / BITS_PER_BYTE; - bitidx &= (BITS_PER_BYTE-1); + byte_bitidx = bitidx / BITS_PER_FLAGS; + bitidx &= (BITS_PER_FLAGS - 1); byte = bitmap[byte_bitidx]; return (byte >> bitidx) & mask; } -unsigned char get_pfnblock_flags_mask(struct page *page, unsigned long pfn, +pageblockflags_t get_pfnblock_flags_mask(struct page *page, unsigned long pfn, unsigned long mask) { return __get_pfnblock_flags_mask(page, pfn, mask); @@ -513,17 +513,17 @@ void set_pfnblock_flags_mask(struct page *page, unsigned long flags, unsigned long pfn, unsigned long mask) { - unsigned char *bitmap; + pageblockflags_t *bitmap; unsigned long bitidx, byte_bitidx; - unsigned char old_byte, byte; + pageblockflags_t old_byte, byte; - BUILD_BUG_ON(NR_PAGEBLOCK_BITS != BITS_PER_BYTE); + BUILD_BUG_ON(NR_PAGEBLOCK_BITS != BITS_PER_FLAGS); BUILD_BUG_ON(MIGRATE_TYPES > (1 << PB_migratetype_bits)); bitmap = get_pageblock_bitmap(page, pfn); bitidx = pfn_to_bitidx(page, pfn); - byte_bitidx = bitidx / BITS_PER_BYTE; - bitidx &= (BITS_PER_BYTE-1); + byte_bitidx = bitidx / BITS_PER_FLAGS; + bitidx &= (BITS_PER_FLAGS - 1); VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page); -- 1.8.3.1