diff options
Diffstat (limited to 'target/linux/generic/patches-4.4/053-0002-ubifs-Use-dirty_writeback_interval-value-for-wbuf-ti.patch')
| -rw-r--r-- | target/linux/generic/patches-4.4/053-0002-ubifs-Use-dirty_writeback_interval-value-for-wbuf-ti.patch | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/target/linux/generic/patches-4.4/053-0002-ubifs-Use-dirty_writeback_interval-value-for-wbuf-ti.patch b/target/linux/generic/patches-4.4/053-0002-ubifs-Use-dirty_writeback_interval-value-for-wbuf-ti.patch new file mode 100644 index 0000000000..9313cd557e --- /dev/null +++ b/target/linux/generic/patches-4.4/053-0002-ubifs-Use-dirty_writeback_interval-value-for-wbuf-ti.patch @@ -0,0 +1,66 @@ +From 1b7fc2c0069f3864a3dda15430b7aded31c0bfcc Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl> +Date: Tue, 20 Sep 2016 10:36:15 +0200 +Subject: [PATCH] ubifs: Use dirty_writeback_interval value for wbuf timer +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +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: Rafał Miłecki <rafal@milecki.pl> +Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> +Signed-off-by: Richard Weinberger <richard@nod.at> +--- + fs/ubifs/io.c | 8 ++++---- + fs/ubifs/ubifs.h | 4 ---- + 2 files changed, 4 insertions(+), 8 deletions(-) + +--- a/fs/ubifs/io.c ++++ b/fs/ubifs/io.c +@@ -452,11 +452,11 @@ static enum hrtimer_restart wbuf_timer_c + */ + static void new_wbuf_timer_nolock(struct ubifs_wbuf *wbuf) + { +- ktime_t softlimit = ktime_set(WBUF_TIMEOUT_SOFTLIMIT, 0); +- unsigned long long delta; ++ ktime_t softlimit = ms_to_ktime(dirty_writeback_interval * 10); ++ unsigned long long delta = dirty_writeback_interval; + +- delta = WBUF_TIMEOUT_HARDLIMIT - WBUF_TIMEOUT_SOFTLIMIT; +- delta *= 1000000000ULL; ++ /* centi to milli, milli to nano, then 10% */ ++ delta *= 10ULL * NSEC_PER_MSEC / 10ULL; + + ubifs_assert(!hrtimer_active(&wbuf->timer)); + ubifs_assert(delta <= ULONG_MAX); +--- a/fs/ubifs/ubifs.h ++++ b/fs/ubifs/ubifs.h +@@ -106,10 +106,6 @@ + */ + #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) */ + #define MAX_INUM 0xFFFFFFFF + |