From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752789Ab3LFENQ (ORCPT ); Thu, 5 Dec 2013 23:13:16 -0500 Received: from mailout3.samsung.com ([203.254.224.33]:9291 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752645Ab3LFENF (ORCPT ); Thu, 5 Dec 2013 23:13:05 -0500 MIME-version: 1.0 Content-type: text/plain; charset=UTF-8 X-AuditID: cbfee68d-b7f5c6d000004aff-dc-52a14ece41a1 Content-transfer-encoding: 8BIT Message-id: <1386303123.2101.18.camel@kjgkr> Subject: Re: [f2fs-dev] [PATCH 2/5 V2] f2fs: add unlikely() macro for compiler optimization From: Jaegeuk Kim Reply-to: jaegeuk.kim@samsung.com To: Chao Yu Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, =?UTF-8?Q?=E8=B0=AD=E5=A7=9D?= Date: Fri, 06 Dec 2013 13:12:03 +0900 In-reply-to: <000001cef19a$a4bed330$ee3c7990$@samsung.com> References: <000001cef19a$a4bed330$ee3c7990$@samsung.com> Organization: Samsung X-Mailer: Evolution 3.2.3-0ubuntu6 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrHIsWRmVeSWpSXmKPExsVy+t8zQ91zfguDDJqemVn8b/rIZnFpkbvF nr0nWSwu75rDZtG68DyzA6vH7gWfmTz6tqxi9Pi8SS6AOYrLJiU1J7MstUjfLoErY9kWz4J1 rhUver8zNjD2mncxcnJICJhINHTvY4awxSQu3FvP1sXIxSEksIxRYvXWAywwRf9+vmeCSCxi lPh1+A0jSIJXQFDix+R7QEUcHMwC8hJHLmWDhJkF1CUmzVvEDFH/Cqj+3m8miHodiafbV4P1 CgvESjTPXcUM0ssmoC2xeb8BSFhIQFHi7f67rCC2iICSxK/5i1hB5jALLGSUOLjgJhtIPYuA qkTfZF2QGk4BK4mmBa/YIHotJeYv/A7Wyy8gKnF44Xaox5Qkdrd3soPMkRA4xy5x/jXE/SwC AhLfJh8Cu19CQFZi0wGoekmJgytusExglJiF5MtZCF/OQvLlAkbmVYyiqQXJBcVJ6UWGesWJ ucWleel6yfm5mxghcde7g/H2AetDjMlAGycyS4km5wPjNq8k3tDYzMjC1MTU2Mjc0ow0YSVx 3qSHSUFCAumJJanZqakFqUXxRaU5qcWHGJk4OKUaGEUuz4rNP5ds8WwX88Jrs1comWYKv6pV vt2+++3Zlp9nP2z7uu69nm+v8lLLpGuJ+jaHN8hJyuslJfYtOzB7psm+QJ1jv5hbk7Rr/mc1 u7/LnKac2hXty/XGV2n/1qg2n7umPsJLfmgs+8XSqxqlxXZrCtvO2c7B9XMdd9oGLT/Jdnxx wIc7/UosxRmJhlrMRcWJAGqebUHRAgAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprNKsWRmVeSWpSXmKPExsVy+t9jAd1zfguDDM6sN7T43/SRzeLSIneL PXtPslhc3jWHzaJ14XlmB1aP3Qs+M3n0bVnF6PF5k1wAc1QDo01GamJKapFCal5yfkpmXrqt kndwvHO8qZmBoa6hpYW5kkJeYm6qrZKLT4CuW2YO0EolhbLEnFKgUEBicbGSvh2mCaEhbroW MI0Rur4hQXA9RgZoIGEdY8ayLZ4F61wrXvR+Z2xg7DXvYuTkkBAwkfj38z0ThC0mceHeerYu Ri4OIYFFjBK/Dr9hBEnwCghK/Jh8j6WLkYODWUBe4silbJAws4C6xKR5i5gh6l8B1d/7zQRR ryPxdPtqsF5hgViJ5rmrmEF62QS0JTbvNwAJCwkoSrzdf5cVxBYRUJL4NX8RK8gcZoGFjBIH F9xkA6lnEVCV6JusC1LDKWAl0bTgFRtEr6XE/IXfwXr5BUQlDi/czgxxv5LE7vZO9gmMQrOQ XD0L4epZSK5ewMi8ilE0tSC5oDgpPddQrzgxt7g0L10vOT93EyM4qp9J7WBc2WBxiFGAg1GJ h5dj1YIgIdbEsuLK3EOMEhzMSiK8PeILg4R4UxIrq1KL8uOLSnNSiw8xJgPdPZFZSjQ5H5hw 8kriDY1NzIwsjcwsjEzMzUkTVhLnPdBqHSgkkJ5YkpqdmlqQWgSzhYmDU6qBcdfmSdcUBTaG zk7fm+PZpWHz6YbVdx6t/TPN5sbGzpvy/GeVdHHYtFfm5/dIxbwqWTutm9GDad32fTVbPbgC IwvTJe/v9Gzz1P5bfvhSeFjfq73BMwUfiDX76fLKWfW8ZhUVPf1pZ/uf3LzNF65uV4g4Fu/u 9P+PoZTVLZGfT3+KzOXMWLcrRImlOCPRUIu5qDgRABbcIxUuAwAA DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Just in case, if you agreed the following comments, I'll fix those and merge the patch by myself. Thanks, 2013-12-05 (목), 17:15 +0800, Chao Yu: > As we know, some of our branch condition will rarely be true. So we could add > 'unlikely' to let compiler optimize these code, by this way we could drop > unneeded 'jump' assemble code to improve performance. > > change log: > o add *unlikely* as many as possible across the whole source files at once > suggested by Jaegeuk Kim. > > Suggested-by: Jaegeuk Kim > Signed-off-by: Chao Yu > --- > fs/f2fs/checkpoint.c | 10 +++++----- > fs/f2fs/data.c | 4 ++-- > fs/f2fs/dir.c | 4 ++-- > fs/f2fs/f2fs.h | 8 ++++---- > fs/f2fs/node.c | 16 ++++++++-------- > fs/f2fs/segment.h | 2 +- > 6 files changed, 22 insertions(+), 22 deletions(-) > > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c > index 38f4a224..6580808 100644 > --- a/fs/f2fs/checkpoint.c > +++ b/fs/f2fs/checkpoint.c > @@ -82,8 +82,8 @@ static int f2fs_write_meta_page(struct page *page, > struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); > > /* Should not write any meta pages, if any IO error was occurred */ > - if (wbc->for_reclaim || sbi->por_doing || > - is_set_ckpt_flags(F2FS_CKPT(sbi), CP_ERROR_FLAG)) { > + if (unlikely(wbc->for_reclaim || sbi->por_doing || > + is_set_ckpt_flags(F2FS_CKPT(sbi), CP_ERROR_FLAG))) { if (unlikely(sbi->por_doing || is_set_ckpt_flags(F2FS_CKPT(sbi), CP_ERROR_FLAG))) goto redirty_out; if (wbc->for_reclaim) goto redirty_out; redirty_out: > dec_page_count(sbi, F2FS_DIRTY_META); > wbc->pages_skipped++; > set_page_dirty(page); > @@ -137,7 +137,7 @@ long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type, > nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, > PAGECACHE_TAG_DIRTY, > min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1); > - if (nr_pages == 0) > + if (unlikely(nr_pages == 0)) > break; > > for (i = 0; i < nr_pages; i++) { > @@ -150,7 +150,7 @@ long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type, > unlock_page(page); > break; > } > - if (nwritten++ >= nr_to_write) > + if (unlikely(nwritten++ >= nr_to_write)) nwritten++; if (unlikely(nwritten >= nr_to_write)) > break; > } > pagevec_release(&pvec); > @@ -200,7 +200,7 @@ int acquire_orphan_inode(struct f2fs_sb_info *sbi) > max_orphans = (sbi->blocks_per_seg - 2 - NR_CURSEG_TYPE) > * F2FS_ORPHANS_PER_BLOCK; > mutex_lock(&sbi->orphan_inode_mutex); > - if (sbi->n_orphans >= max_orphans) > + if (unlikely(sbi->n_orphans >= max_orphans)) > err = -ENOSPC; > else > sbi->n_orphans++; > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 4e2fc09..2ce5a9e 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -251,7 +251,7 @@ int reserve_new_block(struct dnode_of_data *dn) > > if (is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)) > return -EPERM; > - if (!inc_valid_block_count(sbi, dn->inode, 1)) > + if (unlikely(!inc_valid_block_count(sbi, dn->inode, 1))) > return -ENOSPC; > > trace_f2fs_reserve_new_block(dn->inode, dn->nid, dn->ofs_in_node); > @@ -711,7 +711,7 @@ static int f2fs_write_data_page(struct page *page, > > zero_user_segment(page, offset, PAGE_CACHE_SIZE); > write: > - if (sbi->por_doing) { > + if (unlikely(sbi->por_doing)) { > err = AOP_WRITEPAGE_ACTIVATE; > goto redirty_out; > } > diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c > index 594fc1b..0cc26ba 100644 > --- a/fs/f2fs/dir.c > +++ b/fs/f2fs/dir.c > @@ -190,7 +190,7 @@ struct f2fs_dir_entry *f2fs_find_entry(struct inode *dir, > unsigned int max_depth; > unsigned int level; > > - if (namelen > F2FS_NAME_LEN) > + if (unlikely(namelen > F2FS_NAME_LEN)) > return NULL; > > if (npages == 0) > @@ -461,7 +461,7 @@ int __f2fs_add_link(struct inode *dir, const struct qstr *name, struct inode *in > } > > start: > - if (current_depth == MAX_DIR_HASH_DEPTH) > + if (unlikely(current_depth == MAX_DIR_HASH_DEPTH)) > return -ENOSPC; > > /* Increase the depth, if required */ > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index 10eca02..dca18b3 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -574,7 +574,7 @@ static inline void f2fs_unlock_all(struct f2fs_sb_info *sbi) > static inline int check_nid_range(struct f2fs_sb_info *sbi, nid_t nid) > { > WARN_ON((nid >= NM_I(sbi)->max_nid)); > - if (nid >= NM_I(sbi)->max_nid) > + if (unlikely(nid >= NM_I(sbi)->max_nid)) > return -EINVAL; > return 0; > } > @@ -600,7 +600,7 @@ static inline bool inc_valid_block_count(struct f2fs_sb_info *sbi, > spin_lock(&sbi->stat_lock); > valid_block_count = > sbi->total_valid_block_count + (block_t)count; > - if (valid_block_count > sbi->user_block_count) { > + if (unlikely(valid_block_count > sbi->user_block_count)) { > spin_unlock(&sbi->stat_lock); > return false; > } > @@ -719,13 +719,13 @@ static inline bool inc_valid_node_count(struct f2fs_sb_info *sbi, > spin_lock(&sbi->stat_lock); > > valid_block_count = sbi->total_valid_block_count + 1; > - if (valid_block_count > sbi->user_block_count) { > + if (unlikely(valid_block_count > sbi->user_block_count)) { > spin_unlock(&sbi->stat_lock); > return false; > } > > valid_node_count = sbi->total_valid_node_count + 1; > - if (valid_node_count > sbi->total_node_count) { > + if (unlikely(valid_node_count > sbi->total_node_count)) { > spin_unlock(&sbi->stat_lock); > return false; > } > diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c > index 5e2588f..48cbf76 100644 > --- a/fs/f2fs/node.c > +++ b/fs/f2fs/node.c > @@ -94,7 +94,7 @@ static void ra_nat_pages(struct f2fs_sb_info *sbi, int nid) > int i; > > for (i = 0; i < FREE_NID_PAGES; i++, nid += NAT_ENTRY_PER_BLOCK) { > - if (nid >= nm_i->max_nid) > + if (unlikely(nid >= nm_i->max_nid)) > nid = 0; > index = current_nat_addr(sbi, nid); > > @@ -1160,7 +1160,7 @@ int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino) > struct page *page = pvec.pages[i]; > > /* until radix tree lookup accepts end_index */ > - if (page->index > end) > + if (unlikely(page->index > end)) > continue; > > if (ino && ino_of_node(page) == ino) { > @@ -1190,7 +1190,7 @@ static int f2fs_write_node_page(struct page *page, > block_t new_addr; > struct node_info ni; > > - if (sbi->por_doing) > + if (unlikely(sbi->por_doing)) > goto redirty_out; > > wait_on_page_writeback(page); > @@ -1326,7 +1326,7 @@ static int add_free_nid(struct f2fs_nm_info *nm_i, nid_t nid, bool build) > return -1; > > /* 0 nid should not be used */ > - if (nid == 0) > + if (unlikely(nid == 0)) > return 0; > > if (build) { > @@ -1379,7 +1379,7 @@ static void scan_nat_page(struct f2fs_nm_info *nm_i, > > for (; i < NAT_ENTRY_PER_BLOCK; i++, start_nid++) { > > - if (start_nid >= nm_i->max_nid) > + if (unlikely(start_nid >= nm_i->max_nid)) > break; > > blk_addr = le32_to_cpu(nat_blk->entries[i].block_addr); > @@ -1413,7 +1413,7 @@ static void build_free_nids(struct f2fs_sb_info *sbi) > f2fs_put_page(page, 1); > > nid += (NAT_ENTRY_PER_BLOCK - (nid % NAT_ENTRY_PER_BLOCK)); > - if (nid >= nm_i->max_nid) > + if (unlikely(nid >= nm_i->max_nid)) > nid = 0; > > if (i++ == FREE_NID_PAGES) > @@ -1447,7 +1447,7 @@ bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid) > struct free_nid *i = NULL; > struct list_head *this; > retry: > - if (sbi->total_valid_node_count + 1 >= nm_i->max_nid) > + if (unlikely(sbi->total_valid_node_count + 1 >= nm_i->max_nid)) > return false; > > spin_lock(&nm_i->free_nid_list_lock); > @@ -1557,7 +1557,7 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page) > new_ni = old_ni; > new_ni.ino = ino; > > - if (!inc_valid_node_count(sbi, NULL)) > + if (unlikely(!inc_valid_node_count(sbi, NULL))) > WARN_ON(1); > set_node_addr(sbi, &new_ni, NEW_ADDR); > inc_valid_inode_count(sbi); > diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h > index 26812fc..ea56376 100644 > --- a/fs/f2fs/segment.h > +++ b/fs/f2fs/segment.h > @@ -457,7 +457,7 @@ static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi, int freed) > int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES); > int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS); > > - if (sbi->por_doing) > + if (unlikely(sbi->por_doing)) > return false; > > return ((free_sections(sbi) + freed) <= (node_secs + 2 * dent_secs + -- Jaegeuk Kim Samsung