Commit 1b7fc2c0 authored by Rafał Miłecki's avatar Rafał Miłecki Committed by Richard Weinberger

ubifs: Use dirty_writeback_interval value for wbuf timer

Right now wbuf timer has hardcoded timeouts and there is no place for
manual adjustments. Some projects / cases many need that though. Few
file systems allow doing that by respecting dirty_writeback_interval
that can be set using sysctl (dirty_writeback_centisecs).

Lowering dirty_writeback_interval could be some way of dealing with user
space apps lacking proper fsyncs. This is definitely *not* a perfect
solution but we don't have ideal (user space) world. There were already
advanced discussions on this matter, mostly when ext4 was introduced and
it wasn't behaving as ext3. Anyway, the final decision was to add some
hacks to the ext4, as trying to fix whole user space or adding new API
was pointless.

We can't (and shouldn't?) just follow ext4. We can't e.g. sync on close
as this would cause too many commits and flash wearing. On the other
hand we still should allow some trade-off between -o sync and default
wbuf timeout. Respecting dirty_writeback_interval should allow some sane
cutomizations if used warily.
Signed-off-by: default avatarRafał Miłecki <rafal@milecki.pl>
Reviewed-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
parent 854826c9
...@@ -452,11 +452,11 @@ static enum hrtimer_restart wbuf_timer_callback_nolock(struct hrtimer *timer) ...@@ -452,11 +452,11 @@ static enum hrtimer_restart wbuf_timer_callback_nolock(struct hrtimer *timer)
*/ */
static void new_wbuf_timer_nolock(struct ubifs_wbuf *wbuf) static void new_wbuf_timer_nolock(struct ubifs_wbuf *wbuf)
{ {
ktime_t softlimit = ktime_set(WBUF_TIMEOUT_SOFTLIMIT, 0); ktime_t softlimit = ms_to_ktime(dirty_writeback_interval * 10);
unsigned long long delta; unsigned long long delta = dirty_writeback_interval;
delta = WBUF_TIMEOUT_HARDLIMIT - WBUF_TIMEOUT_SOFTLIMIT; /* centi to milli, milli to nano, then 10% */
delta *= 1000000000ULL; delta *= 10ULL * NSEC_PER_MSEC / 10ULL;
ubifs_assert(!hrtimer_active(&wbuf->timer)); ubifs_assert(!hrtimer_active(&wbuf->timer));
ubifs_assert(delta <= ULONG_MAX); ubifs_assert(delta <= ULONG_MAX);
......
...@@ -83,10 +83,6 @@ ...@@ -83,10 +83,6 @@
*/ */
#define BGT_NAME_PATTERN "ubifs_bgt%d_%d" #define BGT_NAME_PATTERN "ubifs_bgt%d_%d"
/* Write-buffer synchronization timeout interval in seconds */
#define WBUF_TIMEOUT_SOFTLIMIT 3
#define WBUF_TIMEOUT_HARDLIMIT 5
/* Maximum possible inode number (only 32-bit inodes are supported now) */ /* Maximum possible inode number (only 32-bit inodes are supported now) */
#define MAX_INUM 0xFFFFFFFF #define MAX_INUM 0xFFFFFFFF
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment