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Diffstat (limited to 'mm')
-rw-r--r--mm/filemap.c3
-rw-r--r--mm/madvise.c2
-rw-r--r--mm/rmap.c1
-rw-r--r--mm/swapfile.c29
-rw-r--r--mm/truncate.c3
-rw-r--r--mm/vmscan.c71
6 files changed, 66 insertions, 43 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index a8251a8d345..f820e600f1a 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -78,9 +78,6 @@
* ->i_mutex (generic_file_buffered_write)
* ->mmap_sem (fault_in_pages_readable->do_page_fault)
*
- * ->i_mutex
- * ->i_alloc_sem (various)
- *
* inode_wb_list_lock
* sb_lock (fs/fs-writeback.c)
* ->mapping->tree_lock (__sync_single_inode)
diff --git a/mm/madvise.c b/mm/madvise.c
index 2221491ed50..74bf193eff0 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -218,7 +218,7 @@ static long madvise_remove(struct vm_area_struct *vma,
endoff = (loff_t)(end - vma->vm_start - 1)
+ ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
- /* vmtruncate_range needs to take i_mutex and i_alloc_sem */
+ /* vmtruncate_range needs to take i_mutex */
up_read(&current->mm->mmap_sem);
error = vmtruncate_range(mapping->host, offset, endoff);
down_read(&current->mm->mmap_sem);
diff --git a/mm/rmap.c b/mm/rmap.c
index 23295f65ae4..2540a39eea4 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -21,7 +21,6 @@
* Lock ordering in mm:
*
* inode->i_mutex (while writing or truncating, not reading or faulting)
- * inode->i_alloc_sem (vmtruncate_range)
* mm->mmap_sem
* page->flags PG_locked (lock_page)
* mapping->i_mmap_mutex
diff --git a/mm/swapfile.c b/mm/swapfile.c
index ff8dc1a18cb..1b8c3390724 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1681,19 +1681,14 @@ out:
}
#ifdef CONFIG_PROC_FS
-struct proc_swaps {
- struct seq_file seq;
- int event;
-};
-
static unsigned swaps_poll(struct file *file, poll_table *wait)
{
- struct proc_swaps *s = file->private_data;
+ struct seq_file *seq = file->private_data;
poll_wait(file, &proc_poll_wait, wait);
- if (s->event != atomic_read(&proc_poll_event)) {
- s->event = atomic_read(&proc_poll_event);
+ if (seq->poll_event != atomic_read(&proc_poll_event)) {
+ seq->poll_event = atomic_read(&proc_poll_event);
return POLLIN | POLLRDNORM | POLLERR | POLLPRI;
}
@@ -1783,24 +1778,16 @@ static const struct seq_operations swaps_op = {
static int swaps_open(struct inode *inode, struct file *file)
{
- struct proc_swaps *s;
+ struct seq_file *seq;
int ret;
- s = kmalloc(sizeof(struct proc_swaps), GFP_KERNEL);
- if (!s)
- return -ENOMEM;
-
- file->private_data = s;
-
ret = seq_open(file, &swaps_op);
- if (ret) {
- kfree(s);
+ if (ret)
return ret;
- }
- s->seq.private = s;
- s->event = atomic_read(&proc_poll_event);
- return ret;
+ seq = file->private_data;
+ seq->poll_event = atomic_read(&proc_poll_event);
+ return 0;
}
static const struct file_operations proc_swaps_operations = {
diff --git a/mm/truncate.c b/mm/truncate.c
index e13f22efaad..003c6c685fc 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -622,12 +622,11 @@ int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
return -ENOSYS;
mutex_lock(&inode->i_mutex);
- down_write(&inode->i_alloc_sem);
+ inode_dio_wait(inode);
unmap_mapping_range(mapping, offset, (end - offset), 1);
inode->i_op->truncate_range(inode, offset, end);
/* unmap again to remove racily COWed private pages */
unmap_mapping_range(mapping, offset, (end - offset), 1);
- up_write(&inode->i_alloc_sem);
mutex_unlock(&inode->i_mutex);
return 0;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index d036e59d302..febbc044e79 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -250,49 +250,90 @@ unsigned long shrink_slab(struct shrink_control *shrink,
unsigned long long delta;
unsigned long total_scan;
unsigned long max_pass;
+ int shrink_ret = 0;
+ long nr;
+ long new_nr;
+ long batch_size = shrinker->batch ? shrinker->batch
+ : SHRINK_BATCH;
+ /*
+ * copy the current shrinker scan count into a local variable
+ * and zero it so that other concurrent shrinker invocations
+ * don't also do this scanning work.
+ */
+ do {
+ nr = shrinker->nr;
+ } while (cmpxchg(&shrinker->nr, nr, 0) != nr);
+
+ total_scan = nr;
max_pass = do_shrinker_shrink(shrinker, shrink, 0);
delta = (4 * nr_pages_scanned) / shrinker->seeks;
delta *= max_pass;
do_div(delta, lru_pages + 1);
- shrinker->nr += delta;
- if (shrinker->nr < 0) {
+ total_scan += delta;
+ if (total_scan < 0) {
printk(KERN_ERR "shrink_slab: %pF negative objects to "
"delete nr=%ld\n",
- shrinker->shrink, shrinker->nr);
- shrinker->nr = max_pass;
+ shrinker->shrink, total_scan);
+ total_scan = max_pass;
}
/*
+ * We need to avoid excessive windup on filesystem shrinkers
+ * due to large numbers of GFP_NOFS allocations causing the
+ * shrinkers to return -1 all the time. This results in a large
+ * nr being built up so when a shrink that can do some work
+ * comes along it empties the entire cache due to nr >>>
+ * max_pass. This is bad for sustaining a working set in
+ * memory.
+ *
+ * Hence only allow the shrinker to scan the entire cache when
+ * a large delta change is calculated directly.
+ */
+ if (delta < max_pass / 4)
+ total_scan = min(total_scan, max_pass / 2);
+
+ /*
* Avoid risking looping forever due to too large nr value:
* never try to free more than twice the estimate number of
* freeable entries.
*/
- if (shrinker->nr > max_pass * 2)
- shrinker->nr = max_pass * 2;
+ if (total_scan > max_pass * 2)
+ total_scan = max_pass * 2;
- total_scan = shrinker->nr;
- shrinker->nr = 0;
+ trace_mm_shrink_slab_start(shrinker, shrink, nr,
+ nr_pages_scanned, lru_pages,
+ max_pass, delta, total_scan);
- while (total_scan >= SHRINK_BATCH) {
- long this_scan = SHRINK_BATCH;
- int shrink_ret;
+ while (total_scan >= batch_size) {
int nr_before;
nr_before = do_shrinker_shrink(shrinker, shrink, 0);
shrink_ret = do_shrinker_shrink(shrinker, shrink,
- this_scan);
+ batch_size);
if (shrink_ret == -1)
break;
if (shrink_ret < nr_before)
ret += nr_before - shrink_ret;
- count_vm_events(SLABS_SCANNED, this_scan);
- total_scan -= this_scan;
+ count_vm_events(SLABS_SCANNED, batch_size);
+ total_scan -= batch_size;
cond_resched();
}
- shrinker->nr += total_scan;
+ /*
+ * move the unused scan count back into the shrinker in a
+ * manner that handles concurrent updates. If we exhausted the
+ * scan, there is no need to do an update.
+ */
+ do {
+ nr = shrinker->nr;
+ new_nr = total_scan + nr;
+ if (total_scan <= 0)
+ break;
+ } while (cmpxchg(&shrinker->nr, nr, new_nr) != nr);
+
+ trace_mm_shrink_slab_end(shrinker, shrink_ret, nr, new_nr);
}
up_read(&shrinker_rwsem);
out:
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-28 17:38:41 +0000