static inline void __wb_writeout_inc(struct bdi_writeback *wb)
{
__inc_wb_stat(wb, WB_WRITTEN);
- __fprop_inc_percpu_max(&writeout_completions, &wb->bdi->completions,
+ __fprop_inc_percpu_max(&writeout_completions, &wb->completions,
wb->bdi->max_prop_frac);
/* First event after period switching was turned off? */
if (!unlikely(writeout_period_time)) {
/*
* Obtain an accurate fraction of the BDI's portion.
*/
-static void bdi_writeout_fraction(struct backing_dev_info *bdi,
- long *numerator, long *denominator)
+static void wb_writeout_fraction(struct bdi_writeback *wb,
+ long *numerator, long *denominator)
{
- fprop_fraction_percpu(&writeout_completions, &bdi->completions,
+ fprop_fraction_percpu(&writeout_completions, &wb->completions,
numerator, denominator);
}
}
/**
- * bdi_dirty_limit - @bdi's share of dirty throttling threshold
- * @bdi: the backing_dev_info to query
+ * wb_dirty_limit - @wb's share of dirty throttling threshold
+ * @wb: bdi_writeback to query
* @dirty: global dirty limit in pages
*
- * Returns @bdi's dirty limit in pages. The term "dirty" in the context of
+ * Returns @wb's dirty limit in pages. The term "dirty" in the context of
* dirty balancing includes all PG_dirty, PG_writeback and NFS unstable pages.
*
* Note that balance_dirty_pages() will only seriously take it as a hard limit
* control. For example, when the device is completely stalled due to some error
* conditions, or when there are 1000 dd tasks writing to a slow 10MB/s USB key.
* In the other normal situations, it acts more gently by throttling the tasks
- * more (rather than completely block them) when the bdi dirty pages go high.
+ * more (rather than completely block them) when the wb dirty pages go high.
*
* It allocates high/low dirty limits to fast/slow devices, in order to prevent
* - starving fast devices
* - piling up dirty pages (that will take long time to sync) on slow devices
*
- * The bdi's share of dirty limit will be adapting to its throughput and
+ * The wb's share of dirty limit will be adapting to its throughput and
* bounded by the bdi->min_ratio and/or bdi->max_ratio parameters, if set.
*/
-unsigned long bdi_dirty_limit(struct backing_dev_info *bdi, unsigned long dirty)
+unsigned long wb_dirty_limit(struct bdi_writeback *wb, unsigned long dirty)
{
- u64 bdi_dirty;
+ struct backing_dev_info *bdi = wb->bdi;
+ u64 wb_dirty;
long numerator, denominator;
/*
* Calculate this BDI's share of the dirty ratio.
*/
- bdi_writeout_fraction(bdi, &numerator, &denominator);
+ wb_writeout_fraction(wb, &numerator, &denominator);
- bdi_dirty = (dirty * (100 - bdi_min_ratio)) / 100;
- bdi_dirty *= numerator;
- do_div(bdi_dirty, denominator);
+ wb_dirty = (dirty * (100 - bdi_min_ratio)) / 100;
+ wb_dirty *= numerator;
+ do_div(wb_dirty, denominator);
- bdi_dirty += (dirty * bdi->min_ratio) / 100;
- if (bdi_dirty > (dirty * bdi->max_ratio) / 100)
- bdi_dirty = dirty * bdi->max_ratio / 100;
+ wb_dirty += (dirty * bdi->min_ratio) / 100;
+ if (wb_dirty > (dirty * bdi->max_ratio) / 100)
+ wb_dirty = dirty * bdi->max_ratio / 100;
- return bdi_dirty;
+ return wb_dirty;
}
/*
* card's bdi_dirty may rush to many times higher than bdi_setpoint.
* - the bdi dirty thresh drops quickly due to change of JBOD workload
*/
-static unsigned long bdi_position_ratio(struct backing_dev_info *bdi,
- unsigned long thresh,
- unsigned long bg_thresh,
- unsigned long dirty,
- unsigned long bdi_thresh,
- unsigned long bdi_dirty)
+static unsigned long wb_position_ratio(struct bdi_writeback *wb,
+ unsigned long thresh,
+ unsigned long bg_thresh,
+ unsigned long dirty,
+ unsigned long bdi_thresh,
+ unsigned long bdi_dirty)
{
- unsigned long write_bw = bdi->avg_write_bandwidth;
+ unsigned long write_bw = wb->avg_write_bandwidth;
unsigned long freerun = dirty_freerun_ceiling(thresh, bg_thresh);
unsigned long limit = hard_dirty_limit(thresh);
unsigned long x_intercept;
* consume arbitrary amount of RAM because it is accounted in
* NR_WRITEBACK_TEMP which is not involved in calculating "nr_dirty".
*
- * Here, in bdi_position_ratio(), we calculate pos_ratio based on
+ * Here, in wb_position_ratio(), we calculate pos_ratio based on
* two values: bdi_dirty and bdi_thresh. Let's consider an example:
* total amount of RAM is 16GB, bdi->max_ratio is equal to 1%, global
* limits are set by default to 10% and 20% (background and throttle).
* Then bdi_thresh is 1% of 20% of 16GB. This amounts to ~8K pages.
- * bdi_dirty_limit(bdi, bg_thresh) is about ~4K pages. bdi_setpoint is
+ * wb_dirty_limit(wb, bg_thresh) is about ~4K pages. bdi_setpoint is
* about ~6K pages (as the average of background and throttle bdi
* limits). The 3rd order polynomial will provide positive feedback if
* bdi_dirty is under bdi_setpoint and vice versa.
* much earlier than global "freerun" is reached (~23MB vs. ~2.3GB
* in the example above).
*/
- if (unlikely(bdi->capabilities & BDI_CAP_STRICTLIMIT)) {
+ if (unlikely(wb->bdi->capabilities & BDI_CAP_STRICTLIMIT)) {
long long bdi_pos_ratio;
unsigned long bdi_bg_thresh;
return pos_ratio;
}
-static void bdi_update_write_bandwidth(struct backing_dev_info *bdi,
- unsigned long elapsed,
- unsigned long written)
+static void wb_update_write_bandwidth(struct bdi_writeback *wb,
+ unsigned long elapsed,
+ unsigned long written)
{
const unsigned long period = roundup_pow_of_two(3 * HZ);
- unsigned long avg = bdi->avg_write_bandwidth;
- unsigned long old = bdi->write_bandwidth;
+ unsigned long avg = wb->avg_write_bandwidth;
+ unsigned long old = wb->write_bandwidth;
u64 bw;
/*
* @written may have decreased due to account_page_redirty().
* Avoid underflowing @bw calculation.
*/
- bw = written - min(written, bdi->written_stamp);
+ bw = written - min(written, wb->written_stamp);
bw *= HZ;
if (unlikely(elapsed > period)) {
do_div(bw, elapsed);
avg = bw;
goto out;
}
- bw += (u64)bdi->write_bandwidth * (period - elapsed);
+ bw += (u64)wb->write_bandwidth * (period - elapsed);
bw >>= ilog2(period);
/*
avg += (old - avg) >> 3;
out:
- bdi->write_bandwidth = bw;
- bdi->avg_write_bandwidth = avg;
+ wb->write_bandwidth = bw;
+ wb->avg_write_bandwidth = avg;
}
/*
* Normal bdi tasks will be curbed at or below it in long term.
* Obviously it should be around (write_bw / N) when there are N dd tasks.
*/
-static void bdi_update_dirty_ratelimit(struct backing_dev_info *bdi,
- unsigned long thresh,
- unsigned long bg_thresh,
- unsigned long dirty,
- unsigned long bdi_thresh,
- unsigned long bdi_dirty,
- unsigned long dirtied,
- unsigned long elapsed)
+static void wb_update_dirty_ratelimit(struct bdi_writeback *wb,
+ unsigned long thresh,
+ unsigned long bg_thresh,
+ unsigned long dirty,
+ unsigned long bdi_thresh,
+ unsigned long bdi_dirty,
+ unsigned long dirtied,
+ unsigned long elapsed)
{
unsigned long freerun = dirty_freerun_ceiling(thresh, bg_thresh);
unsigned long limit = hard_dirty_limit(thresh);
unsigned long setpoint = (freerun + limit) / 2;
- unsigned long write_bw = bdi->avg_write_bandwidth;
- unsigned long dirty_ratelimit = bdi->dirty_ratelimit;
+ unsigned long write_bw = wb->avg_write_bandwidth;
+ unsigned long dirty_ratelimit = wb->dirty_ratelimit;
unsigned long dirty_rate;
unsigned long task_ratelimit;
unsigned long balanced_dirty_ratelimit;
* The dirty rate will match the writeout rate in long term, except
* when dirty pages are truncated by userspace or re-dirtied by FS.
*/
- dirty_rate = (dirtied - bdi->dirtied_stamp) * HZ / elapsed;
+ dirty_rate = (dirtied - wb->dirtied_stamp) * HZ / elapsed;
- pos_ratio = bdi_position_ratio(bdi, thresh, bg_thresh, dirty,
- bdi_thresh, bdi_dirty);
+ pos_ratio = wb_position_ratio(wb, thresh, bg_thresh, dirty,
+ bdi_thresh, bdi_dirty);
/*
* task_ratelimit reflects each dd's dirty rate for the past 200ms.
*/
/*
* For strictlimit case, calculations above were based on bdi counters
- * and limits (starting from pos_ratio = bdi_position_ratio() and up to
+ * and limits (starting from pos_ratio = wb_position_ratio() and up to
* balanced_dirty_ratelimit = task_ratelimit * write_bw / dirty_rate).
* Hence, to calculate "step" properly, we have to use bdi_dirty as
* "dirty" and bdi_setpoint as "setpoint".
*
* We rampup dirty_ratelimit forcibly if bdi_dirty is low because
* it's possible that bdi_thresh is close to zero due to inactivity
- * of backing device (see the implementation of bdi_dirty_limit()).
+ * of backing device (see the implementation of wb_dirty_limit()).
*/
- if (unlikely(bdi->capabilities & BDI_CAP_STRICTLIMIT)) {
+ if (unlikely(wb->bdi->capabilities & BDI_CAP_STRICTLIMIT)) {
dirty = bdi_dirty;
if (bdi_dirty < 8)
setpoint = bdi_dirty + 1;
else
setpoint = (bdi_thresh +
- bdi_dirty_limit(bdi, bg_thresh)) / 2;
+ wb_dirty_limit(wb, bg_thresh)) / 2;
}
if (dirty < setpoint) {
- x = min3(bdi->balanced_dirty_ratelimit,
+ x = min3(wb->balanced_dirty_ratelimit,
balanced_dirty_ratelimit, task_ratelimit);
if (dirty_ratelimit < x)
step = x - dirty_ratelimit;
} else {
- x = max3(bdi->balanced_dirty_ratelimit,
+ x = max3(wb->balanced_dirty_ratelimit,
balanced_dirty_ratelimit, task_ratelimit);
if (dirty_ratelimit > x)
step = dirty_ratelimit - x;
else
dirty_ratelimit -= step;
- bdi->dirty_ratelimit = max(dirty_ratelimit, 1UL);
- bdi->balanced_dirty_ratelimit = balanced_dirty_ratelimit;
+ wb->dirty_ratelimit = max(dirty_ratelimit, 1UL);
+ wb->balanced_dirty_ratelimit = balanced_dirty_ratelimit;
- trace_bdi_dirty_ratelimit(bdi, dirty_rate, task_ratelimit);
+ trace_bdi_dirty_ratelimit(wb->bdi, dirty_rate, task_ratelimit);
}
-void __bdi_update_bandwidth(struct backing_dev_info *bdi,
- unsigned long thresh,
- unsigned long bg_thresh,
- unsigned long dirty,
- unsigned long bdi_thresh,
- unsigned long bdi_dirty,
- unsigned long start_time)
+void __wb_update_bandwidth(struct bdi_writeback *wb,
+ unsigned long thresh,
+ unsigned long bg_thresh,
+ unsigned long dirty,
+ unsigned long bdi_thresh,
+ unsigned long bdi_dirty,
+ unsigned long start_time)
{
unsigned long now = jiffies;
- unsigned long elapsed = now - bdi->bw_time_stamp;
+ unsigned long elapsed = now - wb->bw_time_stamp;
unsigned long dirtied;
unsigned long written;
if (elapsed < BANDWIDTH_INTERVAL)
return;
- dirtied = percpu_counter_read(&bdi->wb.stat[WB_DIRTIED]);
- written = percpu_counter_read(&bdi->wb.stat[WB_WRITTEN]);
+ dirtied = percpu_counter_read(&wb->stat[WB_DIRTIED]);
+ written = percpu_counter_read(&wb->stat[WB_WRITTEN]);
/*
* Skip quiet periods when disk bandwidth is under-utilized.
* (at least 1s idle time between two flusher runs)
*/
- if (elapsed > HZ && time_before(bdi->bw_time_stamp, start_time))
+ if (elapsed > HZ && time_before(wb->bw_time_stamp, start_time))
goto snapshot;
if (thresh) {
global_update_bandwidth(thresh, dirty, now);
- bdi_update_dirty_ratelimit(bdi, thresh, bg_thresh, dirty,
- bdi_thresh, bdi_dirty,
- dirtied, elapsed);
+ wb_update_dirty_ratelimit(wb, thresh, bg_thresh, dirty,
+ bdi_thresh, bdi_dirty,
+ dirtied, elapsed);
}
- bdi_update_write_bandwidth(bdi, elapsed, written);
+ wb_update_write_bandwidth(wb, elapsed, written);
snapshot:
- bdi->dirtied_stamp = dirtied;
- bdi->written_stamp = written;
- bdi->bw_time_stamp = now;
+ wb->dirtied_stamp = dirtied;
+ wb->written_stamp = written;
+ wb->bw_time_stamp = now;
}
-static void bdi_update_bandwidth(struct backing_dev_info *bdi,
- unsigned long thresh,
- unsigned long bg_thresh,
- unsigned long dirty,
- unsigned long bdi_thresh,
- unsigned long bdi_dirty,
- unsigned long start_time)
+static void wb_update_bandwidth(struct bdi_writeback *wb,
+ unsigned long thresh,
+ unsigned long bg_thresh,
+ unsigned long dirty,
+ unsigned long bdi_thresh,
+ unsigned long bdi_dirty,
+ unsigned long start_time)
{
- if (time_is_after_eq_jiffies(bdi->bw_time_stamp + BANDWIDTH_INTERVAL))
+ if (time_is_after_eq_jiffies(wb->bw_time_stamp + BANDWIDTH_INTERVAL))
return;
- spin_lock(&bdi->wb.list_lock);
- __bdi_update_bandwidth(bdi, thresh, bg_thresh, dirty,
- bdi_thresh, bdi_dirty, start_time);
- spin_unlock(&bdi->wb.list_lock);
+ spin_lock(&wb->list_lock);
+ __wb_update_bandwidth(wb, thresh, bg_thresh, dirty,
+ bdi_thresh, bdi_dirty, start_time);
+ spin_unlock(&wb->list_lock);
}
/*
return 1;
}
-static unsigned long bdi_max_pause(struct backing_dev_info *bdi,
- unsigned long bdi_dirty)
+static unsigned long wb_max_pause(struct bdi_writeback *wb,
+ unsigned long bdi_dirty)
{
- unsigned long bw = bdi->avg_write_bandwidth;
+ unsigned long bw = wb->avg_write_bandwidth;
unsigned long t;
/*
return min_t(unsigned long, t, MAX_PAUSE);
}
-static long bdi_min_pause(struct backing_dev_info *bdi,
- long max_pause,
- unsigned long task_ratelimit,
- unsigned long dirty_ratelimit,
- int *nr_dirtied_pause)
+static long wb_min_pause(struct bdi_writeback *wb,
+ long max_pause,
+ unsigned long task_ratelimit,
+ unsigned long dirty_ratelimit,
+ int *nr_dirtied_pause)
{
- long hi = ilog2(bdi->avg_write_bandwidth);
- long lo = ilog2(bdi->dirty_ratelimit);
+ long hi = ilog2(wb->avg_write_bandwidth);
+ long lo = ilog2(wb->dirty_ratelimit);
long t; /* target pause */
long pause; /* estimated next pause */
int pages; /* target nr_dirtied_pause */
return pages >= DIRTY_POLL_THRESH ? 1 + t / 2 : t;
}
-static inline void bdi_dirty_limits(struct backing_dev_info *bdi,
- unsigned long dirty_thresh,
- unsigned long background_thresh,
- unsigned long *bdi_dirty,
- unsigned long *bdi_thresh,
- unsigned long *bdi_bg_thresh)
+static inline void wb_dirty_limits(struct bdi_writeback *wb,
+ unsigned long dirty_thresh,
+ unsigned long background_thresh,
+ unsigned long *bdi_dirty,
+ unsigned long *bdi_thresh,
+ unsigned long *bdi_bg_thresh)
{
- struct bdi_writeback *wb = &bdi->wb;
unsigned long wb_reclaimable;
/*
* In this case we don't want to hard throttle the USB key
* dirtiers for 100 seconds until bdi_dirty drops under
* bdi_thresh. Instead the auxiliary bdi control line in
- * bdi_position_ratio() will let the dirtier task progress
+ * wb_position_ratio() will let the dirtier task progress
* at some rate <= (write_bw / 2) for bringing down bdi_dirty.
*/
- *bdi_thresh = bdi_dirty_limit(bdi, dirty_thresh);
+ *bdi_thresh = wb_dirty_limit(wb, dirty_thresh);
if (bdi_bg_thresh)
*bdi_bg_thresh = dirty_thresh ? div_u64((u64)*bdi_thresh *
unsigned long dirty_ratelimit;
unsigned long pos_ratio;
struct backing_dev_info *bdi = inode_to_bdi(mapping->host);
+ struct bdi_writeback *wb = &bdi->wb;
bool strictlimit = bdi->capabilities & BDI_CAP_STRICTLIMIT;
unsigned long start_time = jiffies;
global_dirty_limits(&background_thresh, &dirty_thresh);
if (unlikely(strictlimit)) {
- bdi_dirty_limits(bdi, dirty_thresh, background_thresh,
- &bdi_dirty, &bdi_thresh, &bg_thresh);
+ wb_dirty_limits(wb, dirty_thresh, background_thresh,
+ &bdi_dirty, &bdi_thresh, &bg_thresh);
dirty = bdi_dirty;
thresh = bdi_thresh;
bdi_start_background_writeback(bdi);
if (!strictlimit)
- bdi_dirty_limits(bdi, dirty_thresh, background_thresh,
- &bdi_dirty, &bdi_thresh, NULL);
+ wb_dirty_limits(wb, dirty_thresh, background_thresh,
+ &bdi_dirty, &bdi_thresh, NULL);
dirty_exceeded = (bdi_dirty > bdi_thresh) &&
((nr_dirty > dirty_thresh) || strictlimit);
- if (dirty_exceeded && !bdi->dirty_exceeded)
- bdi->dirty_exceeded = 1;
+ if (dirty_exceeded && !wb->dirty_exceeded)
+ wb->dirty_exceeded = 1;
- bdi_update_bandwidth(bdi, dirty_thresh, background_thresh,
- nr_dirty, bdi_thresh, bdi_dirty,
- start_time);
+ wb_update_bandwidth(wb, dirty_thresh, background_thresh,
+ nr_dirty, bdi_thresh, bdi_dirty,
+ start_time);
- dirty_ratelimit = bdi->dirty_ratelimit;
- pos_ratio = bdi_position_ratio(bdi, dirty_thresh,
- background_thresh, nr_dirty,
- bdi_thresh, bdi_dirty);
+ dirty_ratelimit = wb->dirty_ratelimit;
+ pos_ratio = wb_position_ratio(wb, dirty_thresh,
+ background_thresh, nr_dirty,
+ bdi_thresh, bdi_dirty);
task_ratelimit = ((u64)dirty_ratelimit * pos_ratio) >>
RATELIMIT_CALC_SHIFT;
- max_pause = bdi_max_pause(bdi, bdi_dirty);
- min_pause = bdi_min_pause(bdi, max_pause,
- task_ratelimit, dirty_ratelimit,
- &nr_dirtied_pause);
+ max_pause = wb_max_pause(wb, bdi_dirty);
+ min_pause = wb_min_pause(wb, max_pause,
+ task_ratelimit, dirty_ratelimit,
+ &nr_dirtied_pause);
if (unlikely(task_ratelimit == 0)) {
period = max_pause;
* more page. However bdi_dirty has accounting errors. So use
* the larger and more IO friendly wb_stat_error.
*/
- if (bdi_dirty <= wb_stat_error(&bdi->wb))
+ if (bdi_dirty <= wb_stat_error(wb))
break;
if (fatal_signal_pending(current))
break;
}
- if (!dirty_exceeded && bdi->dirty_exceeded)
- bdi->dirty_exceeded = 0;
+ if (!dirty_exceeded && wb->dirty_exceeded)
+ wb->dirty_exceeded = 0;
if (writeback_in_progress(bdi))
return;
void balance_dirty_pages_ratelimited(struct address_space *mapping)
{
struct backing_dev_info *bdi = inode_to_bdi(mapping->host);
+ struct bdi_writeback *wb = &bdi->wb;
int ratelimit;
int *p;
return;
ratelimit = current->nr_dirtied_pause;
- if (bdi->dirty_exceeded)
+ if (wb->dirty_exceeded)
ratelimit = min(ratelimit, 32 >> (PAGE_SHIFT - 10));
preempt_disable();
projects / users / hch / configfs.git / commitdiff