From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752164AbdCAJOt (ORCPT ); Wed, 1 Mar 2017 04:14:49 -0500 Received: from szxga01-in.huawei.com ([45.249.212.187]:3335 "EHLO dggrg01-dlp.huawei.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1750941AbdCAJNn (ORCPT ); Wed, 1 Mar 2017 04:13:43 -0500 From: Chao Yu To: CC: , , , Chao Yu Subject: [PATCH RFC] f2fs: combine nat_bits and free_nid_bitmap cache Date: Wed, 1 Mar 2017 17:10:13 +0800 Message-ID: <20170301091013.82838-1-yuchao0@huawei.com> X-Mailer: git-send-email 2.8.2.295.g3f1c1d0 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.120.216.130] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020202.58B68FFF.0280,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 99c4da1bf21c8b1c3d22274b9b2a2259 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Both nat_bits cache and free_nid_bitmap cache provide same functionality as a intermediate cache between free nid cache and disk, but with different granularity of indicating free nid range, and different persistence policy. nat_bits cache provides better persistence ability, and free_nid_bitmap provides better granularity. In this patch we combine advantage of both caches, so finally policy of the intermediate cache would be: - init: load free nid status from nat_bits into free_nid_bitmap - lookup: scan free_nid_bitmap before load NAT blocks - update: update free_nid_bitmap in real-time - persistence: udpate and persist nat_bits in checkpoint Signed-off-by: Chao Yu --- fs/f2fs/node.c | 109 +++++++++++++++++++++------------------------------------ 1 file changed, 39 insertions(+), 70 deletions(-) diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 1a759d45b7e4..6c027b6833f4 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -338,9 +338,6 @@ static void set_node_addr(struct f2fs_sb_info *sbi, struct node_info *ni, set_nat_flag(e, IS_CHECKPOINTED, false); __set_nat_cache_dirty(nm_i, e); - if (enabled_nat_bits(sbi, NULL) && new_blkaddr == NEW_ADDR) - clear_bit_le(NAT_BLOCK_OFFSET(ni->nid), nm_i->empty_nat_bits); - /* update fsync_mark if its inode nat entry is still alive */ if (ni->nid != ni->ino) e = __lookup_nat_cache(nm_i, ni->ino); @@ -1920,58 +1917,6 @@ static void scan_free_nid_bits(struct f2fs_sb_info *sbi) up_read(&nm_i->nat_tree_lock); } -static int scan_nat_bits(struct f2fs_sb_info *sbi) -{ - struct f2fs_nm_info *nm_i = NM_I(sbi); - struct page *page; - unsigned int i = 0; - nid_t nid; - - if (!enabled_nat_bits(sbi, NULL)) - return -EAGAIN; - - down_read(&nm_i->nat_tree_lock); -check_empty: - i = find_next_bit_le(nm_i->empty_nat_bits, nm_i->nat_blocks, i); - if (i >= nm_i->nat_blocks) { - i = 0; - goto check_partial; - } - - for (nid = i * NAT_ENTRY_PER_BLOCK; nid < (i + 1) * NAT_ENTRY_PER_BLOCK; - nid++) { - if (unlikely(nid >= nm_i->max_nid)) - break; - add_free_nid(sbi, nid, true); - } - - if (nm_i->nid_cnt[FREE_NID_LIST] >= MAX_FREE_NIDS) - goto out; - i++; - goto check_empty; - -check_partial: - i = find_next_zero_bit_le(nm_i->full_nat_bits, nm_i->nat_blocks, i); - if (i >= nm_i->nat_blocks) { - disable_nat_bits(sbi, true); - up_read(&nm_i->nat_tree_lock); - return -EINVAL; - } - - nid = i * NAT_ENTRY_PER_BLOCK; - page = get_current_nat_page(sbi, nid); - scan_nat_page(sbi, page, nid); - f2fs_put_page(page, 1); - - if (nm_i->nid_cnt[FREE_NID_LIST] < MAX_FREE_NIDS) { - i++; - goto check_partial; - } -out: - up_read(&nm_i->nat_tree_lock); - return 0; -} - static void __build_free_nids(struct f2fs_sb_info *sbi, bool sync, bool mount) { struct f2fs_nm_info *nm_i = NM_I(sbi); @@ -1993,21 +1938,6 @@ static void __build_free_nids(struct f2fs_sb_info *sbi, bool sync, bool mount) if (nm_i->nid_cnt[FREE_NID_LIST]) return; - - /* try to find free nids with nat_bits */ - if (!scan_nat_bits(sbi) && nm_i->nid_cnt[FREE_NID_LIST]) - return; - } - - /* find next valid candidate */ - if (enabled_nat_bits(sbi, NULL)) { - int idx = find_next_zero_bit_le(nm_i->full_nat_bits, - nm_i->nat_blocks, 0); - - if (idx >= nm_i->nat_blocks) - set_sbi_flag(sbi, SBI_NEED_FSCK); - else - nid = idx * NAT_ENTRY_PER_BLOCK; } /* readahead nat pages to be scanned */ @@ -2590,6 +2520,41 @@ static int __get_nat_bitmaps(struct f2fs_sb_info *sbi) return 0; } +inline void load_free_nid_bitmap(struct f2fs_sb_info *sbi) +{ + struct f2fs_nm_info *nm_i = NM_I(sbi); + unsigned int i = 0; + nid_t nid, last_nid; + + for (i = 0; i < nm_i->nat_blocks; i++) { + i = find_next_bit_le(nm_i->empty_nat_bits, nm_i->nat_blocks, i); + if (i >= nm_i->nat_blocks) + break; + + set_bit_le(i, nm_i->nat_block_bitmap); + + nid = i * NAT_ENTRY_PER_BLOCK; + last_nid = (i + 1) * NAT_ENTRY_PER_BLOCK; + + for (; nid < last_nid; nid++) + update_free_nid_bitmap(sbi, nid, true, true); + } + + for (i = 0; i < nm_i->nat_blocks; i++) { + i = find_next_bit_le(nm_i->full_nat_bits, nm_i->nat_blocks, i); + if (i >= nm_i->nat_blocks) + break; + + set_bit_le(i, nm_i->nat_block_bitmap); + + nid = i * NAT_ENTRY_PER_BLOCK; + last_nid = (i + 1) * NAT_ENTRY_PER_BLOCK; + + for (; nid < last_nid; nid++) + update_free_nid_bitmap(sbi, nid, false, true); + } +} + static int init_node_manager(struct f2fs_sb_info *sbi) { struct f2fs_super_block *sb_raw = F2FS_RAW_SUPER(sbi); @@ -2672,6 +2637,10 @@ int init_free_nid_cache(struct f2fs_sb_info *sbi) spin_lock_init(&nm_i->free_nid_lock); + /* load free nid status from nat_bits table */ + if (enabled_nat_bits(sbi, NULL)) + load_free_nid_bitmap(sbi); + return 0; } -- 2.8.2.295.g3f1c1d0