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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 E7AC7C43441 for ; Thu, 29 Nov 2018 07:05:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A8AD020863 for ; Thu, 29 Nov 2018 07:05:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A8AD020863 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-btrfs-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727653AbeK2SJ7 (ORCPT ); Thu, 29 Nov 2018 13:09:59 -0500 Received: from mx2.suse.de ([195.135.220.15]:50096 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725901AbeK2SJ7 (ORCPT ); Thu, 29 Nov 2018 13:09:59 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 1C8A3AD7D; Thu, 29 Nov 2018 07:05:35 +0000 (UTC) Subject: Re: [PATCH v2 1/3] btrfs: remove always true if branch in find_delalloc_range To: Lu Fengqi , linux-btrfs@vger.kernel.org References: <20181128032130.11452-1-lufq.fnst@cn.fujitsu.com> <20181129033338.2647-1-lufq.fnst@cn.fujitsu.com> From: Nikolay Borisov Openpgp: preference=signencrypt Autocrypt: addr=nborisov@suse.com; prefer-encrypt=mutual; keydata= xsFNBFiKBz4BEADNHZmqwhuN6EAzXj9SpPpH/nSSP8YgfwoOqwrP+JR4pIqRK0AWWeWCSwmZ T7g+RbfPFlmQp+EwFWOtABXlKC54zgSf+uulGwx5JAUFVUIRBmnHOYi/lUiE0yhpnb1KCA7f u/W+DkwGerXqhhe9TvQoGwgCKNfzFPZoM+gZrm+kWv03QLUCr210n4cwaCPJ0Nr9Z3c582xc bCUVbsjt7BN0CFa2BByulrx5xD9sDAYIqfLCcZetAqsTRGxM7LD0kh5WlKzOeAXj5r8DOrU2 GdZS33uKZI/kZJZVytSmZpswDsKhnGzRN1BANGP8sC+WD4eRXajOmNh2HL4P+meO1TlM3GLl EQd2shHFY0qjEo7wxKZI1RyZZ5AgJnSmehrPCyuIyVY210CbMaIKHUIsTqRgY5GaNME24w7h TyyVCy2qAM8fLJ4Vw5bycM/u5xfWm7gyTb9V1TkZ3o1MTrEsrcqFiRrBY94Rs0oQkZvunqia c+NprYSaOG1Cta14o94eMH271Kka/reEwSZkC7T+o9hZ4zi2CcLcY0DXj0qdId7vUKSJjEep c++s8ncFekh1MPhkOgNj8pk17OAESanmDwksmzh1j12lgA5lTFPrJeRNu6/isC2zyZhTwMWs k3LkcTa8ZXxh0RfWAqgx/ogKPk4ZxOXQEZetkEyTFghbRH2BIwARAQABzSJOaWtvbGF5IEJv cmlzb3YgPG5ib3Jpc292QHN1c2UuZGU+wsF4BBMBAgAiBQJYijkSAhsDBgsJCAcDAgYVCAIJ CgsEFgIDAQIeAQIXgAAKCRBxvoJG5T8oV/B6D/9a8EcRPdHg8uLEPywuJR8URwXzkofT5bZE IfGF0Z+Lt2ADe+nLOXrwKsamhweUFAvwEUxxnndovRLPOpWerTOAl47lxad08080jXnGfYFS Dc+ew7C3SFI4tFFHln8Y22Q9075saZ2yQS1ywJy+TFPADIprAZXnPbbbNbGtJLoq0LTiESnD w/SUC6sfikYwGRS94Dc9qO4nWyEvBK3Ql8NkoY0Sjky3B0vL572Gq0ytILDDGYuZVo4alUs8 LeXS5ukoZIw1QYXVstDJQnYjFxYgoQ5uGVi4t7FsFM/6ykYDzbIPNOx49Rbh9W4uKsLVhTzG BDTzdvX4ARl9La2kCQIjjWRg+XGuBM5rxT/NaTS78PXjhqWNYlGc5OhO0l8e5DIS2tXwYMDY LuHYNkkpMFksBslldvNttSNei7xr5VwjVqW4vASk2Aak5AleXZS+xIq2FADPS/XSgIaepyTV tkfnyreep1pk09cjfXY4A7qpEFwazCRZg9LLvYVc2M2eFQHDMtXsH59nOMstXx2OtNMcx5p8 0a5FHXE/HoXz3p9bD0uIUq6p04VYOHsMasHqHPbsMAq9V2OCytJQPWwe46bBjYZCOwG0+x58 fBFreP/NiJNeTQPOa6FoxLOLXMuVtpbcXIqKQDoEte9aMpoj9L24f60G4q+pL/54ql2VRscK d87BTQRYigc+ARAAyJSq9EFk28++SLfg791xOh28tLI6Yr8wwEOvM3wKeTfTZd+caVb9gBBy wxYhIopKlK1zq2YP7ZjTP1aPJGoWvcQZ8fVFdK/1nW+Z8/NTjaOx1mfrrtTGtFxVBdSCgqBB jHTnlDYV1R5plJqK+ggEP1a0mr/rpQ9dFGvgf/5jkVpRnH6BY0aYFPprRL8ZCcdv2DeeicOO YMobD5g7g/poQzHLLeT0+y1qiLIFefNABLN06Lf0GBZC5l8hCM3Rpb4ObyQ4B9PmL/KTn2FV Xq/c0scGMdXD2QeWLePC+yLMhf1fZby1vVJ59pXGq+o7XXfYA7xX0JsTUNxVPx/MgK8aLjYW hX+TRA4bCr4uYt/S3ThDRywSX6Hr1lyp4FJBwgyb8iv42it8KvoeOsHqVbuCIGRCXqGGiaeX Wa0M/oxN1vJjMSIEVzBAPi16tztL/wQtFHJtZAdCnuzFAz8ue6GzvsyBj97pzkBVacwp3/Mw qbiu7sDz7yB0d7J2tFBJYNpVt/Lce6nQhrvon0VqiWeMHxgtQ4k92Eja9u80JDaKnHDdjdwq FUikZirB28UiLPQV6PvCckgIiukmz/5ctAfKpyYRGfez+JbAGl6iCvHYt/wAZ7Oqe/3Cirs5 KhaXBcMmJR1qo8QH8eYZ+qhFE3bSPH446+5oEw8A9v5oonKV7zMAEQEAAcLBXwQYAQIACQUC WIoHPgIbDAAKCRBxvoJG5T8oV1pyD/4zdXdOL0lhkSIjJWGqz7Idvo0wjVHSSQCbOwZDWNTN JBTP0BUxHpPu/Z8gRNNP9/k6i63T4eL1xjy4umTwJaej1X15H8Hsh+zakADyWHadbjcUXCkg OJK4NsfqhMuaIYIHbToi9K5pAKnV953xTrK6oYVyd/Rmkmb+wgsbYQJ0Ur1Ficwhp6qU1CaJ mJwFjaWaVgUERoxcejL4ruds66LM9Z1Qqgoer62ZneID6ovmzpCWbi2sfbz98+kW46aA/w8r 7sulgs1KXWhBSv5aWqKU8C4twKjlV2XsztUUsyrjHFj91j31pnHRklBgXHTD/pSRsN0UvM26 lPs0g3ryVlG5wiZ9+JbI3sKMfbdfdOeLxtL25ujs443rw1s/PVghphoeadVAKMPINeRCgoJH zZV/2Z/myWPRWWl/79amy/9MfxffZqO9rfugRBORY0ywPHLDdo9Kmzoxoxp9w3uTrTLZaT9M KIuxEcV8wcVjr+Wr9zRl06waOCkgrQbTPp631hToxo+4rA1jiQF2M80HAet65ytBVR2pFGZF zGYYLqiG+mpUZ+FPjxk9kpkRYz61mTLSY7tuFljExfJWMGfgSg1OxfLV631jV1TcdUnx+h3l Sqs2vMhAVt14zT8mpIuu2VNxcontxgVr1kzYA/tQg32fVRbGr449j1gw57BV9i0vww== Message-ID: <06caabdd-8043-dd94-c593-9b965944215f@suse.com> Date: Thu, 29 Nov 2018 09:05:33 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181129033338.2647-1-lufq.fnst@cn.fujitsu.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 29.11.18 г. 5:33 ч., Lu Fengqi wrote: > The @found is always false when it comes to the if branch. Besides, the > bool type is more suitable for @found. Change the return value of the > function and its caller to bool as well. > > Signed-off-by: Lu Fengqi Reviewed-by: Nikolay Borisov > --- > fs/btrfs/extent_io.c | 31 +++++++++++++++---------------- > fs/btrfs/extent_io.h | 2 +- > fs/btrfs/tests/extent-io-tests.c | 2 +- > 3 files changed, 17 insertions(+), 18 deletions(-) > > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c > index b2769e92b556..4b6b87e63b4a 100644 > --- a/fs/btrfs/extent_io.c > +++ b/fs/btrfs/extent_io.c > @@ -1452,16 +1452,16 @@ int find_first_extent_bit(struct extent_io_tree *tree, u64 start, > * find a contiguous range of bytes in the file marked as delalloc, not > * more than 'max_bytes'. start and end are used to return the range, > * > - * 1 is returned if we find something, 0 if nothing was in the tree > + * true is returned if we find something, false if nothing was in the tree > */ > -static noinline u64 find_delalloc_range(struct extent_io_tree *tree, > +static noinline bool find_delalloc_range(struct extent_io_tree *tree, > u64 *start, u64 *end, u64 max_bytes, > struct extent_state **cached_state) > { > struct rb_node *node; > struct extent_state *state; > u64 cur_start = *start; > - u64 found = 0; > + bool found = false; > u64 total_bytes = 0; > > spin_lock(&tree->lock); > @@ -1472,8 +1472,7 @@ static noinline u64 find_delalloc_range(struct extent_io_tree *tree, > */ > node = tree_search(tree, cur_start); > if (!node) { > - if (!found) > - *end = (u64)-1; > + *end = (u64)-1; > goto out; > } > > @@ -1493,7 +1492,7 @@ static noinline u64 find_delalloc_range(struct extent_io_tree *tree, > *cached_state = state; > refcount_inc(&state->refs); > } > - found++; > + found = true; > *end = state->end; > cur_start = state->end + 1; > node = rb_next(node); > @@ -1551,13 +1550,13 @@ static noinline int lock_delalloc_pages(struct inode *inode, > } > > /* > - * find a contiguous range of bytes in the file marked as delalloc, not > - * more than 'max_bytes'. start and end are used to return the range, > + * find and lock a contiguous range of bytes in the file marked as delalloc, > + * not more than 'max_bytes'. start and end are used to return the range, > * > - * 1 is returned if we find something, 0 if nothing was in the tree > + * true is returned if we find something, false if nothing was in the tree > */ > EXPORT_FOR_TESTS > -noinline_for_stack u64 find_lock_delalloc_range(struct inode *inode, > +noinline_for_stack bool find_lock_delalloc_range(struct inode *inode, > struct extent_io_tree *tree, > struct page *locked_page, u64 *start, > u64 *end) > @@ -1565,7 +1564,7 @@ noinline_for_stack u64 find_lock_delalloc_range(struct inode *inode, > u64 max_bytes = BTRFS_MAX_EXTENT_SIZE; > u64 delalloc_start; > u64 delalloc_end; > - u64 found; > + bool found; > struct extent_state *cached_state = NULL; > int ret; > int loops = 0; > @@ -1580,7 +1579,7 @@ noinline_for_stack u64 find_lock_delalloc_range(struct inode *inode, > *start = delalloc_start; > *end = delalloc_end; > free_extent_state(cached_state); > - return 0; > + return false; > } > > /* > @@ -1612,7 +1611,7 @@ noinline_for_stack u64 find_lock_delalloc_range(struct inode *inode, > loops = 1; > goto again; > } else { > - found = 0; > + found = false; > goto out_failed; > } > } > @@ -3195,7 +3194,7 @@ static noinline_for_stack int writepage_delalloc(struct inode *inode, > { > struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree; > u64 page_end = delalloc_start + PAGE_SIZE - 1; > - u64 nr_delalloc; > + bool found; > u64 delalloc_to_write = 0; > u64 delalloc_end = 0; > int ret; > @@ -3203,11 +3202,11 @@ static noinline_for_stack int writepage_delalloc(struct inode *inode, > > > while (delalloc_end < page_end) { > - nr_delalloc = find_lock_delalloc_range(inode, tree, > + found = find_lock_delalloc_range(inode, tree, > page, > &delalloc_start, > &delalloc_end); > - if (nr_delalloc == 0) { > + if (!found) { > delalloc_start = delalloc_end + 1; > continue; > } > diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h > index a1d3ea5a0d32..67881bca15fe 100644 > --- a/fs/btrfs/extent_io.h > +++ b/fs/btrfs/extent_io.h > @@ -521,7 +521,7 @@ int free_io_failure(struct extent_io_tree *failure_tree, > struct extent_io_tree *io_tree, > struct io_failure_record *rec); > #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS > -u64 find_lock_delalloc_range(struct inode *inode, struct extent_io_tree *tree, > +bool find_lock_delalloc_range(struct inode *inode, struct extent_io_tree *tree, > struct page *locked_page, u64 *start, > u64 *end); > #endif > diff --git a/fs/btrfs/tests/extent-io-tests.c b/fs/btrfs/tests/extent-io-tests.c > index d33f9a95bce1..3c46d7f23456 100644 > --- a/fs/btrfs/tests/extent-io-tests.c > +++ b/fs/btrfs/tests/extent-io-tests.c > @@ -66,7 +66,7 @@ static int test_find_delalloc(u32 sectorsize) > u64 max_bytes = BTRFS_MAX_EXTENT_SIZE; > u64 total_dirty = 2 * max_bytes; > u64 start, end, test_start; > - u64 found; > + bool found; > int ret = -EINVAL; > > test_msg("running find delalloc tests"); >