diff options
author | Jaegeuk Kim <jaegeuk.kim@samsung.com> | 2014-01-08 13:45:08 +0900 |
---|---|---|
committer | Ziyan <jaraidaniel@gmail.com> | 2015-05-02 14:36:06 +0200 |
commit | 34fb847ddb689c459e2f3ff494c03471d9d9a547 (patch) | |
tree | 9432db047b09a443b7f2071a5ec8a2d5a3a74fcf /fs/f2fs | |
parent | 1d6f03f2684700541bbb990924b0f26441b18eb2 (diff) | |
download | kernel_samsung_tuna-34fb847ddb689c459e2f3ff494c03471d9d9a547.zip kernel_samsung_tuna-34fb847ddb689c459e2f3ff494c03471d9d9a547.tar.gz kernel_samsung_tuna-34fb847ddb689c459e2f3ff494c03471d9d9a547.tar.bz2 |
f2fs: add a sysfs entry to control max_victim_search
Previously during SSR and GC, the maximum number of retrials to find a victim
segment was hard-coded by MAX_VICTIM_SEARCH, 4096 by default.
This number makes an effect on IO locality, when SSR mode is activated, which
results in performance fluctuation on some low-end devices.
If max_victim_search = 4, the victim will be searched like below.
("D" represents a dirty segment, and "*" indicates a selected victim segment.)
D1 D2 D3 D4 D5 D6 D7 D8 D9
[ * ]
[ * ]
[ * ]
[ ....]
This patch adds a sysfs entry to control the number dynamically through:
/sys/fs/f2fs/$dev/max_victim_search
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Diffstat (limited to 'fs/f2fs')
-rw-r--r-- | fs/f2fs/f2fs.h | 3 | ||||
-rw-r--r-- | fs/f2fs/gc.c | 4 | ||||
-rw-r--r-- | fs/f2fs/gc.h | 2 | ||||
-rw-r--r-- | fs/f2fs/super.c | 6 |
4 files changed, 12 insertions, 3 deletions
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index b47fe7f..5d1dbc8 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -451,6 +451,9 @@ struct f2fs_sb_info { struct f2fs_gc_kthread *gc_thread; /* GC thread */ unsigned int cur_victim_sec; /* current victim section num */ + /* maximum # of trials to find a victim segment for SSR and GC */ + unsigned int max_victim_search; + /* * for stat information. * one is for the LFS mode, and the other is for the SSR mode. diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index 1f8837a..e02b47a 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -163,8 +163,8 @@ static void select_policy(struct f2fs_sb_info *sbi, int gc_type, p->ofs_unit = sbi->segs_per_sec; } - if (p->max_search > MAX_VICTIM_SEARCH) - p->max_search = MAX_VICTIM_SEARCH; + if (p->max_search > sbi->max_victim_search) + p->max_search = sbi->max_victim_search; p->offset = sbi->last_victim[p->gc_mode]; } diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h index aa1c2cc..e423aef 100644 --- a/fs/f2fs/gc.h +++ b/fs/f2fs/gc.h @@ -20,7 +20,7 @@ #define LIMIT_FREE_BLOCK 40 /* percentage over invalid + free space */ /* Search max. number of dirty segments to select a victim segment */ -#define MAX_VICTIM_SEARCH 4096 /* covers 8GB */ +#define DEF_MAX_VICTIM_SEARCH 4096 /* covers 8GB */ struct f2fs_gc_kthread { struct task_struct *f2fs_gc_task; diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 3c3c4dc..aee3404 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -74,6 +74,7 @@ static match_table_t f2fs_tokens = { enum { GC_THREAD, /* struct f2fs_gc_thread */ SM_INFO, /* struct f2fs_sm_info */ + F2FS_SBI, /* struct f2fs_sb_info */ }; struct f2fs_attr { @@ -91,6 +92,8 @@ static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type) return (unsigned char *)sbi->gc_thread; else if (struct_type == SM_INFO) return (unsigned char *)SM_I(sbi); + else if (struct_type == F2FS_SBI) + return (unsigned char *)sbi; return NULL; } @@ -180,6 +183,7 @@ F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy); F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util); +F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search); #define ATTR_LIST(name) (&f2fs_attr_##name.attr) static struct attribute *f2fs_attrs[] = { @@ -191,6 +195,7 @@ static struct attribute *f2fs_attrs[] = { ATTR_LIST(max_small_discards), ATTR_LIST(ipu_policy), ATTR_LIST(min_ipu_util), + ATTR_LIST(max_victim_search), NULL, }; @@ -757,6 +762,7 @@ static void init_sb_info(struct f2fs_sb_info *sbi) sbi->node_ino_num = le32_to_cpu(raw_super->node_ino); sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino); sbi->cur_victim_sec = NULL_SECNO; + sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH; for (i = 0; i < NR_COUNT_TYPE; i++) atomic_set(&sbi->nr_pages[i], 0); |