From 0f6b56ec958d49e2b3dc955cdac6b62702c04b72 Mon Sep 17 00:00:00 2001 From: Daeho Jeong Date: Mon, 2 Aug 2021 21:22:45 -0700 Subject: [PATCH] f2fs: add sysfs node to control ra_pages for fadvise seq file fadvise() allows the user to expand the readahead window to double with POSIX_FADV_SEQUENTIAL, now. But, in some use cases, it is not that sufficient and we need to meet the need in a restricted way. We can control the multiplier value of bdi device readahead between 2 (default) and 256 for POSIX_FADV_SEQUENTIAL advise option. Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- Documentation/ABI/testing/sysfs-fs-f2fs | 6 +++++ fs/f2fs/f2fs.h | 5 +++++ fs/f2fs/file.c | 30 +++++++++++++++++++++++++ fs/f2fs/super.c | 1 + fs/f2fs/sysfs.c | 10 +++++++++ 5 files changed, 52 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs index 845c4be535b0..73211f77d11e 100644 --- a/Documentation/ABI/testing/sysfs-fs-f2fs +++ b/Documentation/ABI/testing/sysfs-fs-f2fs @@ -507,3 +507,9 @@ Date: July 2021 Contact: "Daeho Jeong" Description: You can control for which gc mode the "gc_reclaimed_segments" node shows. Refer to the description of the modes in "gc_reclaimed_segments". + +What: /sys/fs/f2fs//seq_file_ra_mul +Date: July 2021 +Contact: "Daeho Jeong" +Description: You can control the multiplier value of bdi device readahead window size + between 2 (default) and 256 for POSIX_FADV_SEQUENTIAL advise option. diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 8d4665a7a0fb..1b4c482d08e2 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1749,6 +1749,8 @@ struct f2fs_sb_info { unsigned int gc_segment_mode; /* GC state for reclaimed segments */ unsigned int gc_reclaimed_segs[MAX_GC_MODE]; /* Reclaimed segs for each mode */ + unsigned long seq_file_ra_mul; /* multiplier for ra_pages of seq. files in fadvise */ + #ifdef CONFIG_F2FS_FS_COMPRESSION struct kmem_cache *page_array_slab; /* page array entry */ unsigned int page_array_slab_size; /* default page array slab size */ @@ -4003,6 +4005,9 @@ void f2fs_destroy_extent_cache(void); /* * sysfs.c */ +#define MIN_RA_MUL 2 +#define MAX_RA_MUL 256 + int __init f2fs_init_sysfs(void); void f2fs_exit_sysfs(void); int f2fs_register_sysfs(struct f2fs_sb_info *sbi); diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index e931782abdab..7d8ee60f6c1f 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -23,6 +23,7 @@ #include #include #include +#include #include "f2fs.h" #include "node.h" @@ -4344,6 +4345,34 @@ out: return ret; } +static int f2fs_file_fadvise(struct file *filp, loff_t offset, loff_t len, + int advice) +{ + struct inode *inode; + struct address_space *mapping; + struct backing_dev_info *bdi; + + if (advice == POSIX_FADV_SEQUENTIAL) { + inode = file_inode(filp); + if (S_ISFIFO(inode->i_mode)) + return -ESPIPE; + + mapping = filp->f_mapping; + if (!mapping || len < 0) + return -EINVAL; + + bdi = inode_to_bdi(mapping->host); + filp->f_ra.ra_pages = bdi->ra_pages * + F2FS_I_SB(inode)->seq_file_ra_mul; + spin_lock(&filp->f_lock); + filp->f_mode &= ~FMODE_RANDOM; + spin_unlock(&filp->f_lock); + return 0; + } + + return generic_fadvise(filp, offset, len, advice); +} + #ifdef CONFIG_COMPAT struct compat_f2fs_gc_range { u32 sync; @@ -4472,4 +4501,5 @@ const struct file_operations f2fs_file_operations = { #endif .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, + .fadvise = f2fs_file_fadvise, }; diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index a4fed184b811..84cd085020cd 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -3466,6 +3466,7 @@ static void init_sb_info(struct f2fs_sb_info *sbi) sbi->next_victim_seg[FG_GC] = NULL_SEGNO; sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH; sbi->migration_granularity = sbi->segs_per_sec; + sbi->seq_file_ra_mul = MIN_RA_MUL; sbi->dir_level = DEF_DIR_LEVEL; sbi->interval_time[CP_TIME] = DEF_CP_INTERVAL; diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c index f98afd9f9380..0954761341d7 100644 --- a/fs/f2fs/sysfs.c +++ b/fs/f2fs/sysfs.c @@ -540,6 +540,14 @@ out: return count; } + if (!strcmp(a->attr.name, "seq_file_ra_mul")) { + if (t >= MIN_RA_MUL && t <= MAX_RA_MUL) + sbi->seq_file_ra_mul = t; + else + return -EINVAL; + return count; + } + *ui = (unsigned int)t; return count; @@ -765,6 +773,7 @@ F2FS_RW_ATTR(ATGC_INFO, atgc_management, atgc_candidate_count, max_candidate_cou F2FS_RW_ATTR(ATGC_INFO, atgc_management, atgc_age_weight, age_weight); F2FS_RW_ATTR(ATGC_INFO, atgc_management, atgc_age_threshold, age_threshold); +F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, seq_file_ra_mul, seq_file_ra_mul); F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_segment_mode, gc_segment_mode); F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_reclaimed_segments, gc_reclaimed_segs); @@ -840,6 +849,7 @@ static struct attribute *f2fs_attrs[] = { ATTR_LIST(atgc_candidate_count), ATTR_LIST(atgc_age_weight), ATTR_LIST(atgc_age_threshold), + ATTR_LIST(seq_file_ra_mul), ATTR_LIST(gc_segment_mode), ATTR_LIST(gc_reclaimed_segments), NULL,