From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yw0-f198.google.com (mail-yw0-f198.google.com [209.85.161.198]) by kanga.kvack.org (Postfix) with ESMTP id CB9AD28025D for ; Thu, 22 Sep 2016 21:57:25 -0400 (EDT) Received: by mail-yw0-f198.google.com with SMTP id u82so204739685ywc.0 for ; Thu, 22 Sep 2016 18:57:25 -0700 (PDT) Received: from szxga02-in.huawei.com (szxga02-in.huawei.com. [119.145.14.65]) by mx.google.com with ESMTPS id o65si1894955ywb.360.2016.09.22.18.57.22 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 22 Sep 2016 18:57:25 -0700 (PDT) Message-ID: <57E48B30.2000303@huawei.com> Date: Fri, 23 Sep 2016 09:53:52 +0800 From: zhong jiang MIME-Version: 1.0 Subject: [RFC] remove unnecessary condition in remove_inode_hugepages Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Mike Kravetz , Michal Hocko , David Rientjes , Vlastimil Babka , Hugh Dickins Cc: Linux Memory Management List , LKML At present, we need to call hugetlb_fix_reserve_count when hugetlb_unrserve_pages fails, and PagePrivate will decide hugetlb reserves counts. we obtain the page from page cache. and use page both lock_page and mutex_lock. alloc_huge_page add page to page chace always hold lock page, then bail out clearpageprivate before unlock page. but I' m not sure it is right or I miss the points. diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 4ea71eb..010723b 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -462,14 +462,12 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart, * the page, note PagePrivate which is used in case * of error. */ - rsv_on_error = !PagePrivate(page); remove_huge_page(page); freed++; if (!truncate_op) { if (unlikely(hugetlb_unreserve_pages(inode, next, next + 1, 1))) - hugetlb_fix_reserve_counts(inode, - rsv_on_error); + hugetlb_fix_reserve_counts(inode) } unlock_page(page); diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index c26d463..d2e0fc5 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -90,7 +90,7 @@ int dequeue_hwpoisoned_huge_page(struct page *page); bool isolate_huge_page(struct page *page, struct list_head *list); void putback_active_hugepage(struct page *page); void free_huge_page(struct page *page); -void hugetlb_fix_reserve_counts(struct inode *inode, bool restore_reserve); +void hugetlb_fix_reserve_counts(struct inode *inode); extern struct mutex *hugetlb_fault_mutex_table; u32 hugetlb_fault_mutex_hash(struct hstate *h, struct mm_struct *mm, struct vm_area_struct *vma, diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 87e11d8..28a079a 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -567,13 +567,13 @@ retry: * appear as a "reserved" entry instead of simply dangling with incorrect * counts. */ -void hugetlb_fix_reserve_counts(struct inode *inode, bool restore_reserve) +void hugetlb_fix_reserve_counts(struct inode *inode) { struct hugepage_subpool *spool = subpool_inode(inode); long rsv_adjust; rsv_adjust = hugepage_subpool_get_pages(spool, 1); - if (restore_reserve && rsv_adjust) { + if (rsv_adjust) { struct hstate *h = hstate_inode(inode); hugetlb_acct_memory(h, 1); -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org