fs/ufs: get rid of write_super

This patch makes UFS stop using the VFS '->write_super()' method along with
the 's_dirt' superblock flag, because they are on their way out.

The way we implement this is that we schedule a delay job instead relying on
's_dirt' and '->write_super()'.

The whole "superblock write-out" VFS infrastructure is served by the
'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and
writes out all dirty superblocks using the '->write_super()' call-back.  But the
problem with this thread is that it wastes power by waking up the system every
5 seconds, even if there are no diry superblocks, or there are no client
file-systems which would need this (e.g., btrfs does not use
'->write_super()'). So we want to kill it completely and thus, we need to make
file-systems to stop using the '->write_super()' VFS service, and then remove
it together with the kernel thread.

Tested using fsstress from the LTP project.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Artem Bityutskiy 2012-07-12 16:28:08 +03:00 committed by Al Viro
parent 7bd54ef722
commit 9e9ad5f408
5 changed files with 42 additions and 16 deletions

View File

@ -116,7 +116,7 @@ void ufs_free_fragments(struct inode *inode, u64 fragment, unsigned count)
ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
sb->s_dirt = 1;
ufs_mark_sb_dirty(sb);
unlock_super (sb);
UFSD("EXIT\n");
@ -214,7 +214,7 @@ do_more:
goto do_more;
}
sb->s_dirt = 1;
ufs_mark_sb_dirty(sb);
unlock_super (sb);
UFSD("EXIT\n");
return;
@ -557,7 +557,7 @@ static u64 ufs_add_fragments(struct inode *inode, u64 fragment,
ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
sb->s_dirt = 1;
ufs_mark_sb_dirty(sb);
UFSD("EXIT, fragment %llu\n", (unsigned long long)fragment);
@ -677,7 +677,7 @@ succed:
ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
sb->s_dirt = 1;
ufs_mark_sb_dirty(sb);
result += cgno * uspi->s_fpg;
UFSD("EXIT3, result %llu\n", (unsigned long long)result);

View File

@ -116,7 +116,7 @@ void ufs_free_inode (struct inode * inode)
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
sb->s_dirt = 1;
ufs_mark_sb_dirty(sb);
unlock_super (sb);
UFSD("EXIT\n");
}
@ -288,7 +288,7 @@ cg_found:
ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
if (sb->s_flags & MS_SYNCHRONOUS)
ubh_sync_block(UCPI_UBH(ucpi));
sb->s_dirt = 1;
ufs_mark_sb_dirty(sb);
inode->i_ino = cg * uspi->s_ipg + bit;
inode_init_owner(inode, dir, mode);

View File

@ -302,7 +302,7 @@ void ufs_error (struct super_block * sb, const char * function,
if (!(sb->s_flags & MS_RDONLY)) {
usb1->fs_clean = UFS_FSBAD;
ubh_mark_buffer_dirty(USPI_UBH(uspi));
sb->s_dirt = 1;
ufs_mark_sb_dirty(sb);
sb->s_flags |= MS_RDONLY;
}
va_start (args, fmt);
@ -334,7 +334,7 @@ void ufs_panic (struct super_block * sb, const char * function,
if (!(sb->s_flags & MS_RDONLY)) {
usb1->fs_clean = UFS_FSBAD;
ubh_mark_buffer_dirty(USPI_UBH(uspi));
sb->s_dirt = 1;
ufs_mark_sb_dirty(sb);
}
va_start (args, fmt);
vsnprintf (error_buf, sizeof(error_buf), fmt, args);
@ -715,7 +715,6 @@ static int ufs_sync_fs(struct super_block *sb, int wait)
ufs_set_fs_state(sb, usb1, usb3,
UFS_FSOK - fs32_to_cpu(sb, usb1->fs_time));
ufs_put_cstotal(sb);
sb->s_dirt = 0;
UFSD("EXIT\n");
unlock_super(sb);
@ -724,12 +723,31 @@ static int ufs_sync_fs(struct super_block *sb, int wait)
return 0;
}
static void ufs_write_super(struct super_block *sb)
static void delayed_sync_fs(struct work_struct *work)
{
if (!(sb->s_flags & MS_RDONLY))
ufs_sync_fs(sb, 1);
else
sb->s_dirt = 0;
struct ufs_sb_info *sbi;
sbi = container_of(work, struct ufs_sb_info, sync_work.work);
spin_lock(&sbi->work_lock);
sbi->work_queued = 0;
spin_unlock(&sbi->work_lock);
ufs_sync_fs(sbi->sb, 1);
}
void ufs_mark_sb_dirty(struct super_block *sb)
{
struct ufs_sb_info *sbi = UFS_SB(sb);
unsigned long delay;
spin_lock(&sbi->work_lock);
if (!sbi->work_queued) {
delay = msecs_to_jiffies(dirty_writeback_interval * 10);
queue_delayed_work(system_long_wq, &sbi->sync_work, delay);
sbi->work_queued = 1;
}
spin_unlock(&sbi->work_lock);
}
static void ufs_put_super(struct super_block *sb)
@ -740,6 +758,7 @@ static void ufs_put_super(struct super_block *sb)
if (!(sb->s_flags & MS_RDONLY))
ufs_put_super_internal(sb);
cancel_delayed_work_sync(&sbi->sync_work);
ubh_brelse_uspi (sbi->s_uspi);
kfree (sbi->s_uspi);
@ -774,6 +793,7 @@ static int ufs_fill_super(struct super_block *sb, void *data, int silent)
if (!sbi)
goto failed_nomem;
sb->s_fs_info = sbi;
sbi->sb = sb;
UFSD("flag %u\n", (int)(sb->s_flags & MS_RDONLY));
@ -785,6 +805,8 @@ static int ufs_fill_super(struct super_block *sb, void *data, int silent)
}
#endif
mutex_init(&sbi->mutex);
spin_lock_init(&sbi->work_lock);
INIT_DELAYED_WORK(&sbi->sync_work, delayed_sync_fs);
/*
* Set default mount options
* Parse mount options
@ -1304,7 +1326,6 @@ static int ufs_remount (struct super_block *sb, int *mount_flags, char *data)
ufs_set_fs_state(sb, usb1, usb3,
UFS_FSOK - fs32_to_cpu(sb, usb1->fs_time));
ubh_mark_buffer_dirty (USPI_UBH(uspi));
sb->s_dirt = 0;
sb->s_flags |= MS_RDONLY;
} else {
/*
@ -1454,7 +1475,6 @@ static const struct super_operations ufs_super_ops = {
.write_inode = ufs_write_inode,
.evict_inode = ufs_evict_inode,
.put_super = ufs_put_super,
.write_super = ufs_write_super,
.sync_fs = ufs_sync_fs,
.statfs = ufs_statfs,
.remount_fs = ufs_remount,

View File

@ -20,6 +20,10 @@ struct ufs_sb_info {
unsigned s_mount_opt;
struct mutex mutex;
struct task_struct *mutex_owner;
struct super_block *sb;
int work_queued; /* non-zero if the delayed work is queued */
struct delayed_work sync_work; /* FS sync delayed work */
spinlock_t work_lock; /* protects sync_work and work_queued */
};
struct ufs_inode_info {
@ -123,6 +127,7 @@ extern __printf(3, 4)
void ufs_error(struct super_block *, const char *, const char *, ...);
extern __printf(3, 4)
void ufs_panic(struct super_block *, const char *, const char *, ...);
void ufs_mark_sb_dirty(struct super_block *sb);
/* symlink.c */
extern const struct inode_operations ufs_fast_symlink_inode_operations;

View File

@ -34,6 +34,7 @@
#include <linux/kernel.h>
#include <linux/stat.h>
#include <linux/fs.h>
#include <linux/workqueue.h>
#include <asm/div64.h>
typedef __u64 __bitwise __fs64;