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path: root/fs/f2fs/extent_cache.c
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2017-05-23f2fs: fix a bug caused by NULL extent treeYunlei He
Thread A: Thread B: -f2fs_remount -sbi->mount_opt.opt = 0; <--- -f2fs_iget -do_read_inode -f2fs_init_extent_tree -F2FS_I(inode)->extent_tree is NULL -default_options && parse_options -remount return <--- -f2fs_map_blocks -f2fs_lookup_extent_tree -f2fs_bug_on(sbi, !et); The same problem with f2fs_new_inode. Signed-off-by: Yunlei He <heyunlei@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-19f2fs: introduce __check_rb_tree_consistenceChao Yu
Introduce __check_rb_tree_consistence to check consistence of rb-tree based discard cache in runtime. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-19f2fs: use rb-tree to track pending discard commandsChao Yu
Introduce rb-tree based discard cache infrastructure to speed up lookup and merge operation of discard entry. Signed-off-by: Chao Yu <yuchao0@huawei.com> [Jaegeuk Kim: initialize dc to avoid build warning] Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-11f2fs: extract rb-tree operation infrastructureChao Yu
rb-tree lookup/update functions are deeply coupled into extent cache codes, it's very hard to reuse these basic functions, this patch extracts common rb-tree operation infrastructure for latter reusing. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27f2fs: kill __is_extent_sameChao Yu
Since commit ee6d182f2a19 ("f2fs: remove syncing inode page in all the cases") delayed inode element updating from inode cache to node page cache, so once largest cached extent is updated, we can make inode dirty immediately instead of checking and updating it in the end of extent cache update. The above commit didn't clean up unneeded codes in extent_cache.c, let's finish the job in this patch. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-02-27f2fs: replace rw semaphore extent_tree_lock with mutex lockYunlei He
This patch replace rw semaphore extent_tree_lock with mutex lock for no read cases with this lock. Signed-off-by: Yunlei He <heyunlei@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-01-29f2fs: use rb_entry_safeGeliang Tang
Use rb_entry_safe() instead of open-coding it. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-01-29f2fs: fix a problem of using memory after freeYunlei He
This patch fix a problem of using memory after free in function __try_merge_extent_node. Fixes: 0f825ee6e873 ("f2fs: add new interfaces for extent tree") Cc: <stable@vger.kernel.org> Signed-off-by: Yunlei He <heyunlei@huawei.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-11-23f2fs: keep dirty inodes selectively for checkpointJaegeuk Kim
This is to avoid no free segment bug during checkpoint caused by a number of dirty inodes. The case was reported by Chao like this. 1. mount with lazytime option 2. fill 4k file until disk is full 3. sync filesystem 4. read all files in the image 5. umount In this case, we actually don't need to flush dirty inode to inode page during checkpoint. Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-07-15f2fs: disable extent_cache for fcollapse/finsert inodesJaegeuk Kim
This reduces the elapsed time to do xfstests/generic/017. Before: 458 s After: 390 s Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-07-08f2fs: avoid mark_inode_dirtyJaegeuk Kim
Let's check inode's dirtiness before calling mark_inode_dirty. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-06-02f2fs: remove syncing inode page in all the casesJaegeuk Kim
This patch reduces to call them across the whole tree. - sync_inode_page() - update_inode_page() - update_inode() - f2fs_write_inode() Instead, checkpoint will flush all the dirty inode metadata before syncing node pages. Note that, this is doable, since we call mark_inode_dirty_sync() for all inode's field change which needs to update on-disk inode as well. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-06-02f2fs: call mark_inode_dirty_sync for i_field changesJaegeuk Kim
This patch calls mark_inode_dirty_sync() for the following on-disk inode changes. -> largest -> ctime/mtime/atime -> i_current_depth -> i_xattr_nid -> i_pino -> i_advise -> i_flags -> i_mode Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-06-02f2fs: use inode pointer for {set, clear}_inode_flagJaegeuk Kim
This patch refactors to use inode pointer for set_inode_flag and clear_inode_flag. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-05-07f2fs: reuse get_extent_infoChao Yu
Reuse get_extent_info for readability. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-26f2fs: introduce f2fs_update_data_blkaddr for cleanupChao Yu
Add a new help f2fs_update_data_blkaddr to clean up redundant codes. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22f2fs: remove unneeded pointer conversionChao Yu
There are redundant pointer conversion in following call stack: - at position a, inode was been converted to f2fs_file_info. - at position b, f2fs_file_info was been converted to inode again. - truncate_blocks(inode,..) - fi = F2FS_I(inode) ---a - ADDRS_PER_PAGE(node_page, fi) - addrs_per_inode(fi) - inode = &fi->vfs_inode ---b - f2fs_has_inline_xattr(inode) - fi = F2FS_I(inode) - is_inode_flag_set(fi,..) In order to avoid unneeded conversion, alter ADDRS_PER_PAGE and addrs_per_inode to acept parameter with type of inode pointer. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22f2fs: give scheduling point in shrinking pathJaegeuk Kim
It needs to give a chance to be rescheduled while shrinking slab entries. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22f2fs: improve shrink performance of extent nodesHou Pengyang
On the worst case, we need to scan the whole radix tree and every rb-tree to free the victimed extent_nodes when shrinking. Pengyang initially introduced a victim_list to record the victimed extent_nodes, and free these extent_nodes by just scanning a list. Later, Chao Yu enhances the original patch to improve memory footprint by removing victim list. The policy of lru list shrinking becomes: 1) lock lru list's lock 2) trylock extent tree's lock 3) remove extent node from lru list 4) unlock lru list's lock 5) do shrink 6) repeat 1) to 5) Signed-off-by: Hou Pengyang <houpengyang@huawei.com> Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22f2fs: don't set cached_en if it will be freedJaegeuk Kim
If en has empty list pointer, it will be freed sooner, so we don't need to set cached_en with it. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22f2fs: move extent_node list operations being coupled with rbtree operationJaegeuk Kim
This patch moves extent_node list operations to be handled together with its rbtree operations. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-02-22f2fs: reconstruct the code to free an extent_nodeHou Pengyang
There are three steps to free an extent node: 1) list_del_init, 2)__detach_extent_node, 3) kmem_cache_free In path f2fs_destroy_extent_tree, 1->2->3 to free a node, But in path f2fs_update_extent_tree_range, it is 2->1->3. This patch makes all the order to be: 1->2->3 It makes sense, since in the next patch, we import a victim list in the path shrink_extent_tree, we could check if the extent_node is in the victim list by checking the list_empty(). So it is necessary to put 1) first. Signed-off-by: Hou Pengyang <houpengyang@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-01-08f2fs: skip releasing nodes in chindless extent treeChao Yu
If there are no nodes in extent tree, let's skip releasing step to avoid any overhead of grabbing/releasing extent tree lock. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-01-08f2fs: use atomic type for node count in extent treeChao Yu
1. rename field in struct extent_tree from count to node_cnt for readability. 2. alter to use atomic type for node_cnt. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-31f2fs: introduce zombie list for fast shrinking extent treesJaegeuk Kim
This patch removes refcount, and instead, adds zombie_list to shrink directly without radix tree traverse. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-30f2fs: load largest extent all the timeJaegeuk Kim
Otherwise, we can get mismatched largest extent information. One example is: 1. mount f2fs w/ extent_cache 2. make a small extent 3. umount 4. mount f2fs w/o extent_cache 5. update the largest extent 6. umount 7. mount f2fs w/ extent_cache 8. get the old extent made by #2 Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-30f2fs: speed up shrinking extent tree entriesJaegeuk Kim
If there is no candidates for shrinking slab entries, we don't need to traverse any trees at all. Reviewed-by: Chao Yu <chao2.yu@samsung.com> [Jaegeuk Kim: fix missing initialization reported by Yunlei He] Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-22f2fs: use atomic variable for total_extent_treeJaegeuk Kim
It would be better to use atomic variable for total_extent_tree. Reviewed-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04f2fs: kill f2fs_drop_largest_extentChao Yu
For direct IO, f2fs only allocate new address for the block which is not exist in the disk before, its mapping info should not exist in extent cache previously, so here we do not need to call f2fs_drop_largest_extent to drop related cache. Due to no more callers for f2fs_drop_largest_extent now, kill it. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-12-04f2fs: avoid deadlock in f2fs_shrink_extent_treeJaegeuk Kim
While handling extent trees, we can enter into a reclaiming path anytime. If it tries to release some extent nodes in the same extent tree, write_lock(&et->lock) would be hanged. In order to avoid the deadlock, we can just skip it. Note that, if it is an unreferenced tree, we should get write_lock(&et->lock) successfully and release all of therein nodes. Reviewed-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-22f2fs: fix to skip shrinking extent nodesChao Yu
In f2fs_shrink_extent_tree we should stop shrink flow if we have already shrunk enough nodes in extent cache. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-09f2fs: introduce __try_update_largest_extentChao Yu
This patch adds a new helper __try_update_largest_extent for cleanup. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-09f2fs: optimize code of f2fs_update_extent_tree_rangeFan Li
Fix 2 potential problems: 1. when largest extent needs to be invalidated, it will be reset in __drop_largest_extent, which makes __is_extent_same after always return false, and largest extent unchanged. Now we update it properly. 2. when extent is split and the latter part remains in tree, next_en should be the latter part instead of next extent of original extent. It will cause merge failure if there is in-place update, although there is not, I think this fix will still makes codes less ambiguous. This patch also simplifies codes of invalidating extents, and optimizes the procedues that split extent into two. There are a few modifications after last patch: 1. prev_en now is updated properly. 2. more codes and branches are simplified. Signed-off-by: Fan li <fanofcode.li@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-09f2fs: drop largest extent by rangeFan Li
now we update extent by range, fofs may not be on the largest extent if the new extent overlaps with it. so add a new function to drop largest extent properly. Signed-off-by: Fan li <fanofcode.li@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-09f2fs: declare f2fs_update_extent_tree_range as staticJaegeuk Kim
This function should be static. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-09f2fs: fix incorrect searching position when shrinking extent cacheChao Yu
When shrinking extent cache, we have two steps in the flow: 1) shrink objects which are unreferenced by inodes; 2) shrink objects from LRU list of extent cache. In step 1, if we haven't shrunk enough number of objects, we will try step 2, but before that we didn't update the searching position which may point to last inode index in global extent tree, result in failing to shrink objects by traversing the all inodes' extent tree. In this patch, we reset searching position to beginning of global extent tree for fixing. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-09f2fs: trace in batches extent info updateChao Yu
Rename trace_f2fs_update_extent_tree to trace_f2fs_update_extent_tree_range, then expand and enable it to trace in batches extent info updates. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-28f2fs: avoid accessing NULL pointer in f2fs_drop_largest_extentChao Yu
If extent cache is disable, we will encounter oops when triggering direct IO as below: BUG: unable to handle kernel NULL pointer dereference at 0000000c IP: [<f0b9c61e>] f2fs_drop_largest_extent+0xe/0x30 [f2fs] *pdpt = 000000002bb9a001 *pde = 0000000000000000 Oops: 0000 [#1] SMP Modules linked in: f2fs(O) fuse bnep rfcomm bluetooth nfsd dm_crypt nfs_acl auth_rpcgss oid_registry nfs binfmt_misc fscache lockd sunrpc grace snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq snd_timer snd_seq_device snd soundcore joydev psmouse hid_generic i2c_piix4 serio_raw ppdev mac_hid parport_pc lp parport ext4 jbd2 mbcache usbhid hid e1000 CPU: 3 PID: 3608 Comm: dd Tainted: G O 4.2.0-rc4 #12 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 task: ef161600 ti: ebd5e000 task.ti: ebd5e000 EIP: 0060:[<f0b9c61e>] EFLAGS: 00010202 CPU: 3 EIP is at f2fs_drop_largest_extent+0xe/0x30 [f2fs] EAX: 00000000 EBX: ddebc000 ECX: 00000000 EDX: 00000000 ESI: ebd5fdf8 EDI: 00000000 EBP: ebd5fd58 ESP: ebd5fd58 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 CR0: 80050033 CR2: 0000000c CR3: 2c24ee40 CR4: 000006f0 Stack: ebd5fda4 f0b8c005 00000000 00000001 00000000 f0b8c430 c816cd68 ddebc000 ddebc088 00001000 00000555 00000555 ffffffff c160bb00 00055501 00000000 00000000 00000100 00000000 ebd5fe20 f0b8c430 00000046 ef161600 00001000 Call Trace: [<f0b8c005>] __allocate_data_block+0x1a5/0x260 [f2fs] [<f0b8c430>] ? f2fs_direct_IO+0x370/0x440 [f2fs] [<c160bb00>] ? down_read+0x30/0x50 [<f0b8c430>] f2fs_direct_IO+0x370/0x440 [f2fs] [<c113e115>] generic_file_direct_write+0xa5/0x260 [<c10b53f8>] ? current_fs_time+0x18/0x50 [<c113e38b>] __generic_file_write_iter+0xbb/0x210 [<c113e50f>] ? generic_file_write_iter+0x2f/0x320 [<c113e63c>] generic_file_write_iter+0x15c/0x320 [<f0b77f29>] f2fs_file_write_iter+0x39/0x80 [f2fs] [<c11984d9>] __vfs_write+0xa9/0xe0 [<c1199227>] vfs_write+0x97/0x180 [<c119955b>] SyS_write+0x5b/0xd0 [<c160dcd0>] sysenter_do_call+0x12/0x12 Code: 10 8b 50 1c 89 53 14 eb ca 8d 74 26 00 85 f6 74 86 eb a6 0f 0b 90 8d b4 26 00 00 00 00 55 89 e5 3e 8d 74 26 00 8b 80 d4 02 00 00 <8b> 48 0c 39 d1 77 0e 03 48 14 39 ca 73 07 c7 40 14 00 00 00 00 EIP: [<f0b9c61e>] f2fs_drop_largest_extent+0xe/0x30 [f2fs] SS:ESP 0068:ebd5fd58 CR2: 000000000000000c ---[ end trace a38c07026a1afffd ]--- This is because when extent cache is disable, extent_tree pointer in struct f2fs_inode_info should be NULL, but in f2fs_drop_largest_extent we access this NULL pointer directly without checking state of extent cache, then, the oops occurs. Let's fix it by checking state of extent cache before accessing. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-26f2fs: update extent tree in batchesChao Yu
This patch introduce a new helper f2fs_update_extent_tree_range which can do extent mapping update at a specified range. The main idea is: 1) punch all mapping info in extent node(s) which are at a specified range; 2) try to merge new extent mapping with adjacent node, or failing that, insert the mapping into extent tree as a new node. In order to see the benefit, I add a function for stating time stamping count as below: uint64_t rdtsc(void) { uint32_t lo, hi; __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi)); return (uint64_t)hi << 32 | lo; } My test environment is: ubuntu, intel i7-3770, 16G memory, 256g micron ssd. truncation path: update extent cache from truncate_data_blocks_range non-truncataion path: update extent cache from other paths total: all update paths a) Removing 128MB file which has one extent node mapping whole range of file: 1. dd if=/dev/zero of=/mnt/f2fs/128M bs=1M count=128 2. sync 3. rm /mnt/f2fs/128M Before: total count average truncation: 7651022 32768 233.49 Patched: total count average truncation: 3321 33 100.64 b) fsstress: fsstress -d /mnt/f2fs -l 5 -n 100 -p 20 Test times: 5 times. Before: total count average truncation: 5812480.6 20911.6 277.95 non-truncation: 7783845.6 13440.8 579.12 total: 13596326.2 34352.4 395.79 Patched: total count average truncation: 1281283.0 3041.6 421.25 non-truncation: 7355844.4 13662.8 538.38 total: 8637127.4 16704.4 517.06 1) For the updates in truncation path: - we can see updating in batches leads total tsc and update count reducing explicitly; - besides, for a single batched updating, punching multiple extent nodes in a loop, result in executing more operations, so our average tsc increase intensively. 2) For the updates in non-truncation path: - there is a little improvement, that is because for the scenario that we just need to update in the head or tail of extent node, new interface optimize to update info in extent node directly, rather than removing original extent node for updating and then inserting that updated one into cache as new node. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-21f2fs: lookup neighbor extent nodes for merging laterChao Yu
In __lookup_extent_tree_ret we will not try to find neighbor nodes if we find the target node, in this condition, we will lost the chance to merge the new mapping with exist extent node later. So our extent cache of inode will be fragmented after overwrite exist file, we can see the number of extent node increases intensively in following test case: dd if=/dev/zero of=/mnt/f2fs/4m bs=4K count=1024 Extent Cache: - Hit Count: L1-1:0 L1-2:0 L2:0 - Hit Ratio: 0% (0 / 3072) - Inner Struct Count: tree: 1, node: 1 dd if=/dev/zero of=/mnt/f2fs/4m bs=4K count=1024 conv=notrunc Extent Cache: - Hit Count: L1-1:2048 L1-2:0 L2:0 - Hit Ratio: 33% (2048 / 6144) - Inner Struct Count: tree: 1, node: 961 This patch fixes to lookup neighbors of target node for further merging. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-21f2fs: split __insert_extent_tree_ret for readabilityChao Yu
This patch splits __insert_extent_tree_ret into __try_merge_extent_node & __insert_extent_tree for code readability. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-21f2fs: kill dead code in __insert_extent_treeChao Yu
After commit 0f825ee6e873 ("f2fs: add new interfaces for extent tree"), f2fs_init_extent_tree becomes the only caller of __insert_extent_tree, and in f2fs_init_extent_tree, we will only insert extent node in an empty tree, so __try_{back,front}_merge in __insert_extent_tree will never be called. This patch removes these dead codes, besides, rename __insert_extent_tree to __init_extent_tree for readability. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-21f2fs: adjust showing of extent cache statChao Yu
This patch alters to replace total hit stat with rbtree hit stat, and then adjust showing of extent cache stat: Hit Count: L1-1: for largest node hit count; L1-2: for last cached node hit count; L2: for extent node hit after lookuping in rbtree. Hit Ratio: ratio (hit count / total lookup count) Inner Struct Count: tree count, node count. Before: Extent Hit Ratio: 0 / 2 Extent Tree Count: 3 Extent Node Count: 2 Patched: Exten Cacache: - Hit Count: L1-1:4871 L1-2:2074 L2:208 - Hit Ratio: 1% (7153 / 550751) - Inner Struct Count: tree: 26560, node: 11824 Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-21f2fs: add largest/cached stat in extent cacheChao Yu
This patch adds to stat the hit count of largest/cached node for showing in debugfs. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-21f2fs: fix to update cached_en of extent tree properlyFan Li
In f2fs_lookup_extent_tree, et->cached_en was read and updated with only read lock held, it could cause __lookup_extent_tree within return entirely wrong extent_node, if other thread update et->cached_en just before __lookup_extent_tree return. However, there are two things about this patch that need to be noticed: 1. It does no good to arrange the order of concurrent read/write, the result would still be random in such case. 2. It's built on this assumption: the mix up of reads and writes on a single pointer would not make the pointer partially wrong at any time. Please let me know if I'm wrong, thx. Signed-off-by: Fan li <fanofcode.li@samsung.com> Reviewed-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-05f2fs: add new interfaces for extent treeFan Li
Add a lookup and a insertion interface for extent tree. The new lookup return the insert position and the prev/next extents closest to the offset we lookup when find no match. The new insertion uses above parameters to improve performance. There are three possible insertions after the lookup in f2fs_update_extent_tree, two of them insert parts of removed extent back to tree, since no merge happens during this process, new insertion skips the merge check in this scanario; the another insertion inserts a new extent to tree, new insertion uses prev/next extent and insert position to insert this extent directly, and save the time of searching down the tree. As long as tree remains unchanged between lookup and insertion, this would work fine. And the new lookup would be useful when add multi-blocks extent support for insertion interface. Signed-off-by: Fan li <fanofcode.li@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-05f2fs: use atomic_t to record hit ratio info of extent cacheChao Yu
Variables for recording extent cache ratio info were updated without protection, this patch tries to alter them to atomic_t type for more accurate stat. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-04f2fs: maintain extent cache in separated fileChao Yu
This patch moves extent cache related code from data.c into extent_cache.c since extent cache is independent feature, and its codes are not relate to others in data.c, it's better for us to maintain them in separated place. There is no functionality change, but several small coding style fixes including: * rename __drop_largest_extent to f2fs_drop_largest_extent for exporting; * rename misspelled word 'untill' to 'until'; * remove unneeded 'return' in the end of f2fs_destroy_extent_tree(). Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>