summaryrefslogtreecommitdiffstats
path: root/mm/page-writeback.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/page-writeback.c')
-rw-r--r--mm/page-writeback.c81
1 files changed, 53 insertions, 28 deletions
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index c9af72f292..8a1c920901 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -860,13 +860,15 @@ static void mdtc_calc_avail(struct dirty_throttle_control *mdtc,
}
/**
- * __wb_calc_thresh - @wb's share of dirty throttling threshold
+ * __wb_calc_thresh - @wb's share of dirty threshold
* @dtc: dirty_throttle_context of interest
+ * @thresh: dirty throttling or dirty background threshold of wb_domain in @dtc
*
- * Note that balance_dirty_pages() will only seriously take it as a hard limit
- * when sleeping max_pause per page is not enough to keep the dirty pages under
- * 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.
+ * Note that balance_dirty_pages() will only seriously take dirty throttling
+ * threshold as a hard limit when sleeping max_pause per page is not enough
+ * to keep the dirty pages under 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 wb dirty pages go high.
*
@@ -877,19 +879,20 @@ static void mdtc_calc_avail(struct dirty_throttle_control *mdtc,
* 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.
*
- * Return: @wb's dirty limit in pages. The term "dirty" in the context of
- * dirty balancing includes all PG_dirty and PG_writeback pages.
+ * Return: @wb's dirty limit in pages. For dirty throttling limit, the term
+ * "dirty" in the context of dirty balancing includes all PG_dirty and
+ * PG_writeback pages.
*/
-static unsigned long __wb_calc_thresh(struct dirty_throttle_control *dtc)
+static unsigned long __wb_calc_thresh(struct dirty_throttle_control *dtc,
+ unsigned long thresh)
{
struct wb_domain *dom = dtc_dom(dtc);
- unsigned long thresh = dtc->thresh;
u64 wb_thresh;
unsigned long numerator, denominator;
unsigned long wb_min_ratio, wb_max_ratio;
/*
- * Calculate this BDI's share of the thresh ratio.
+ * Calculate this wb's share of the thresh ratio.
*/
fprop_fraction_percpu(&dom->completions, dtc->wb_completions,
&numerator, &denominator);
@@ -909,9 +912,28 @@ static unsigned long __wb_calc_thresh(struct dirty_throttle_control *dtc)
unsigned long wb_calc_thresh(struct bdi_writeback *wb, unsigned long thresh)
{
- struct dirty_throttle_control gdtc = { GDTC_INIT(wb),
- .thresh = thresh };
- return __wb_calc_thresh(&gdtc);
+ struct dirty_throttle_control gdtc = { GDTC_INIT(wb) };
+
+ return __wb_calc_thresh(&gdtc, thresh);
+}
+
+unsigned long cgwb_calc_thresh(struct bdi_writeback *wb)
+{
+ struct dirty_throttle_control gdtc = { GDTC_INIT_NO_WB };
+ struct dirty_throttle_control mdtc = { MDTC_INIT(wb, &gdtc) };
+ unsigned long filepages = 0, headroom = 0, writeback = 0;
+
+ gdtc.avail = global_dirtyable_memory();
+ gdtc.dirty = global_node_page_state(NR_FILE_DIRTY) +
+ global_node_page_state(NR_WRITEBACK);
+
+ mem_cgroup_wb_stats(wb, &filepages, &headroom,
+ &mdtc.dirty, &writeback);
+ mdtc.dirty += writeback;
+ mdtc_calc_avail(&mdtc, filepages, headroom);
+ domain_dirty_limits(&mdtc);
+
+ return __wb_calc_thresh(&mdtc, mdtc.thresh);
}
/*
@@ -1658,7 +1680,7 @@ static inline void wb_dirty_limits(struct dirty_throttle_control *dtc)
* wb_position_ratio() will let the dirtier task progress
* at some rate <= (write_bw / 2) for bringing down wb_dirty.
*/
- dtc->wb_thresh = __wb_calc_thresh(dtc);
+ dtc->wb_thresh = __wb_calc_thresh(dtc, dtc->thresh);
dtc->wb_bg_thresh = dtc->thresh ?
div_u64((u64)dtc->wb_thresh * dtc->bg_thresh, dtc->thresh) : 0;
@@ -1697,7 +1719,7 @@ static int balance_dirty_pages(struct bdi_writeback *wb,
struct dirty_throttle_control * const mdtc = mdtc_valid(&mdtc_stor) ?
&mdtc_stor : NULL;
struct dirty_throttle_control *sdtc;
- unsigned long nr_reclaimable; /* = file_dirty */
+ unsigned long nr_dirty;
long period;
long pause;
long max_pause;
@@ -1718,9 +1740,9 @@ static int balance_dirty_pages(struct bdi_writeback *wb,
unsigned long m_thresh = 0;
unsigned long m_bg_thresh = 0;
- nr_reclaimable = global_node_page_state(NR_FILE_DIRTY);
+ nr_dirty = global_node_page_state(NR_FILE_DIRTY);
gdtc->avail = global_dirtyable_memory();
- gdtc->dirty = nr_reclaimable + global_node_page_state(NR_WRITEBACK);
+ gdtc->dirty = nr_dirty + global_node_page_state(NR_WRITEBACK);
domain_dirty_limits(gdtc);
@@ -1771,7 +1793,7 @@ static int balance_dirty_pages(struct bdi_writeback *wb,
* In normal mode, we start background writeout at the lower
* background_thresh, to keep the amount of dirty memory low.
*/
- if (!laptop_mode && nr_reclaimable > gdtc->bg_thresh &&
+ if (!laptop_mode && nr_dirty > gdtc->bg_thresh &&
!writeback_in_progress(wb))
wb_start_background_writeback(wb);
@@ -2117,7 +2139,7 @@ bool wb_over_bg_thresh(struct bdi_writeback *wb)
if (gdtc->dirty > gdtc->bg_thresh)
return true;
- thresh = wb_calc_thresh(gdtc->wb, gdtc->bg_thresh);
+ thresh = __wb_calc_thresh(gdtc, gdtc->bg_thresh);
if (thresh < 2 * wb_stat_error())
reclaimable = wb_stat_sum(wb, WB_RECLAIMABLE);
else
@@ -2137,7 +2159,7 @@ bool wb_over_bg_thresh(struct bdi_writeback *wb)
if (mdtc->dirty > mdtc->bg_thresh)
return true;
- thresh = wb_calc_thresh(mdtc->wb, mdtc->bg_thresh);
+ thresh = __wb_calc_thresh(mdtc, mdtc->bg_thresh);
if (thresh < 2 * wb_stat_error())
reclaimable = wb_stat_sum(wb, WB_RECLAIMABLE);
else
@@ -2313,7 +2335,6 @@ static struct ctl_table vm_page_writeback_sysctls[] = {
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
- {}
};
#endif
@@ -2568,6 +2589,7 @@ done:
folio_batch_release(&wbc->fbatch);
return NULL;
}
+EXPORT_SYMBOL_GPL(writeback_iter);
/**
* write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
@@ -2722,17 +2744,20 @@ void folio_account_cleaned(struct folio *folio, struct bdi_writeback *wb)
}
/*
- * Mark the folio dirty, and set it dirty in the page cache, and mark
- * the inode dirty.
+ * Mark the folio dirty, and set it dirty in the page cache.
*
* If warn is true, then emit a warning if the folio is not uptodate and has
* not been truncated.
*
- * The caller must hold folio_memcg_lock(). Most callers have the folio
- * locked. A few have the folio blocked from truncation through other
- * means (eg zap_vma_pages() has it mapped and is holding the page table
- * lock). This can also be called from mark_buffer_dirty(), which I
- * cannot prove is always protected against truncate.
+ * The caller must hold folio_memcg_lock(). It is the caller's
+ * responsibility to prevent the folio from being truncated while
+ * this function is in progress, although it may have been truncated
+ * before this function is called. Most callers have the folio locked.
+ * A few have the folio blocked from truncation through other means (e.g.
+ * zap_vma_pages() has it mapped and is holding the page table lock).
+ * When called from mark_buffer_dirty(), the filesystem should hold a
+ * reference to the buffer_head that is being marked dirty, which causes
+ * try_to_free_buffers() to fail.
*/
void __folio_mark_dirty(struct folio *folio, struct address_space *mapping,
int warn)