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Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <20230808081651.0d8573551f87de016c018529@hugovil.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.151.185] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To canpemm500002.china.huawei.com (7.192.104.244) X-CFilter-Loop: Reflected X-Rspamd-Queue-Id: D23BB14000D X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: p1p5aqijota877k6yqttwrzghabdxprw X-HE-Tag: 1691497946-973791 X-HE-Meta: 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 Xw5ge7wg UK5ROsHJ9AHGdbkLY74gIaxVI9SjhWXZuX5gFrxeuQeWpvAHQJFH1XXL/rPJpwz6x43zqy3vcfTAHV/ICljU8A3adSkZUWQgSFd7nqyufVmCRz+vk6ws1KAL+FbfivZG7aWzqMYAeFnr3VlF+pR9Ny7L2Tg1diII1ck+v6ib2kpL3dk11kmpMMS4JWPpr8x47qajn28+0V0sF+D0= 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: On 2023/8/8 20:16, Hugo Villeneuve wrote: > On Tue, 8 Aug 2023 10:05:55 +0800 > Miaohe Lin wrote: > >> current_order is guaranteed to '>=' min_order while min_order always '>=' >> order. So current_order must be '>=' order. >> >> Signed-off-by: Miaohe Lin >> --- >> mm/page_alloc.c | 3 +-- >> 1 file changed, 1 insertion(+), 2 deletions(-) >> >> diff --git a/mm/page_alloc.c b/mm/page_alloc.c >> index 96b7c1a7d1f2..d37ec87515d0 100644 >> --- a/mm/page_alloc.c >> +++ b/mm/page_alloc.c >> @@ -2072,8 +2072,7 @@ __rmqueue_fallback(struct zone *zone, int order, int start_migratetype, >> * allocation falls back into a different pageblock than this >> * one, it won't cause permanent fragmentation. >> */ >> - if (!can_steal && start_migratetype == MIGRATE_MOVABLE >> - && current_order > order) >> + if (!can_steal && start_migratetype == MIGRATE_MOVABLE) >> goto find_smallest; > > Hi, > if my analysis is correct, min_order can be initialized to the value of > order before the loop begins. > > In that case, in the last loop iteration, current_order will be > equal to min_order and also to order. The condition 'current_order > > order' will evaluate to false, and the 'if' block should not be > executed? Oh, that's my mistake. Thanks for pointing this out. Will drop this patch. Thanks!