The patch titled
Subject: mm/swap: reduce indentation level
has been added to the -mm mm-unstable branch. Its filename is
mm-swap-reduce-indentation-level.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-swap-reduce-indentation-level.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Yu Zhao <yuzhao@xxxxxxxxxx>
Subject: mm/swap: reduce indentation level
Date: Wed, 10 Jul 2024 20:13:13 -0600
Patch series "mm/swap: remove boilerplate".
Use folio_activate() as an example:
Before this series
------------------
if (!folio_test_active(folio) && !folio_test_unevictable(folio)) {
struct folio_batch *fbatch;
folio_get(folio);
if (!folio_test_clear_lru(folio)) {
folio_put(folio);
return;
}
local_lock(&cpu_fbatches.lock);
fbatch = this_cpu_ptr(&cpu_fbatches.activate);
folio_batch_add_and_move(fbatch, folio, folio_activate_fn);
local_unlock(&cpu_fbatches.lock);
}
}
After this series
-----------------
void folio_activate(struct folio *folio)
{
if (folio_test_active(folio) || folio_test_unevictable(folio))
return;
folio_batch_add_and_move(folio, lru_activate, true);
}
And this is applied to all 6 folio_batch handlers in mm/swap.c.
bloat-o-meter
-------------
add/remove: 12/13 grow/shrink: 3/2 up/down: 4653/-4721 (-68)
...
Total: Before=28083019, After=28082951, chg -0.00%
This patch (of 5):
Reduce indentation level by returning directly when there is no cleanup
needed, i.e.,
if (condition) { | if (condition) {
do_this(); | do_this();
return; | return;
} else { | }
do_that(); |
} | do_that();
and
if (condition) { | if (!condition)
do_this(); | return;
do_that(); |
} | do_this();
return; | do_that();
Presumably the old style became repetitive as the result of copy and
paste.
Link: https://lkml.kernel.org/r/20240711021317.596178-1-yuzhao@xxxxxxxxxx
Link: https://lkml.kernel.org/r/20240711021317.596178-2-yuzhao@xxxxxxxxxx
Signed-off-by: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/swap.c | 209 +++++++++++++++++++++++++++-------------------------
1 file changed, 109 insertions(+), 100 deletions(-)
--- a/mm/swap.c~mm-swap-reduce-indentation-level
+++ a/mm/swap.c
@@ -117,7 +117,9 @@ void __folio_put(struct folio *folio)
if (unlikely(folio_is_zone_device(folio))) {
free_zone_device_folio(folio);
return;
- } else if (folio_test_hugetlb(folio)) {
+ }
+
+ if (folio_test_hugetlb(folio)) {
free_huge_folio(folio);
return;
}
@@ -228,17 +230,19 @@ static void folio_batch_add_and_move(str
if (folio_batch_add(fbatch, folio) && !folio_test_large(folio) &&
!lru_cache_disabled())
return;
+
folio_batch_move_lru(fbatch, move_fn);
}
static void lru_move_tail_fn(struct lruvec *lruvec, struct folio *folio)
{
- if (!folio_test_unevictable(folio)) {
- lruvec_del_folio(lruvec, folio);
- folio_clear_active(folio);
- lruvec_add_folio_tail(lruvec, folio);
- __count_vm_events(PGROTATED, folio_nr_pages(folio));
- }
+ if (folio_test_unevictable(folio))
+ return;
+
+ lruvec_del_folio(lruvec, folio);
+ folio_clear_active(folio);
+ lruvec_add_folio_tail(lruvec, folio);
+ __count_vm_events(PGROTATED, folio_nr_pages(folio));
}
/*
@@ -250,22 +254,23 @@ static void lru_move_tail_fn(struct lruv
*/
void folio_rotate_reclaimable(struct folio *folio)
{
- if (!folio_test_locked(folio) && !folio_test_dirty(folio) &&
- !folio_test_unevictable(folio)) {
- struct folio_batch *fbatch;
- unsigned long flags;
+ struct folio_batch *fbatch;
+ unsigned long flags;
- folio_get(folio);
- if (!folio_test_clear_lru(folio)) {
- folio_put(folio);
- return;
- }
+ if (folio_test_locked(folio) || folio_test_dirty(folio) ||
+ folio_test_unevictable(folio))
+ return;
- local_lock_irqsave(&lru_rotate.lock, flags);
- fbatch = this_cpu_ptr(&lru_rotate.fbatch);
- folio_batch_add_and_move(fbatch, folio, lru_move_tail_fn);
- local_unlock_irqrestore(&lru_rotate.lock, flags);
+ folio_get(folio);
+ if (!folio_test_clear_lru(folio)) {
+ folio_put(folio);
+ return;
}
+
+ local_lock_irqsave(&lru_rotate.lock, flags);
+ fbatch = this_cpu_ptr(&lru_rotate.fbatch);
+ folio_batch_add_and_move(fbatch, folio, lru_move_tail_fn);
+ local_unlock_irqrestore(&lru_rotate.lock, flags);
}
void lru_note_cost(struct lruvec *lruvec, bool file,
@@ -328,18 +333,19 @@ void lru_note_cost_refault(struct folio
static void folio_activate_fn(struct lruvec *lruvec, struct folio *folio)
{
- if (!folio_test_active(folio) && !folio_test_unevictable(folio)) {
- long nr_pages = folio_nr_pages(folio);
+ long nr_pages = folio_nr_pages(folio);
- lruvec_del_folio(lruvec, folio);
- folio_set_active(folio);
- lruvec_add_folio(lruvec, folio);
- trace_mm_lru_activate(folio);
+ if (folio_test_active(folio) || folio_test_unevictable(folio))
+ return;
- __count_vm_events(PGACTIVATE, nr_pages);
- __count_memcg_events(lruvec_memcg(lruvec), PGACTIVATE,
- nr_pages);
- }
+
+ lruvec_del_folio(lruvec, folio);
+ folio_set_active(folio);
+ lruvec_add_folio(lruvec, folio);
+ trace_mm_lru_activate(folio);
+
+ __count_vm_events(PGACTIVATE, nr_pages);
+ __count_memcg_events(lruvec_memcg(lruvec), PGACTIVATE, nr_pages);
}
#ifdef CONFIG_SMP
@@ -353,20 +359,21 @@ static void folio_activate_drain(int cpu
void folio_activate(struct folio *folio)
{
- if (!folio_test_active(folio) && !folio_test_unevictable(folio)) {
- struct folio_batch *fbatch;
+ struct folio_batch *fbatch;
- folio_get(folio);
- if (!folio_test_clear_lru(folio)) {
- folio_put(folio);
- return;
- }
+ if (folio_test_active(folio) || folio_test_unevictable(folio))
+ return;
- local_lock(&cpu_fbatches.lock);
- fbatch = this_cpu_ptr(&cpu_fbatches.activate);
- folio_batch_add_and_move(fbatch, folio, folio_activate_fn);
- local_unlock(&cpu_fbatches.lock);
+ folio_get(folio);
+ if (!folio_test_clear_lru(folio)) {
+ folio_put(folio);
+ return;
}
+
+ local_lock(&cpu_fbatches.lock);
+ fbatch = this_cpu_ptr(&cpu_fbatches.activate);
+ folio_batch_add_and_move(fbatch, folio, folio_activate_fn);
+ local_unlock(&cpu_fbatches.lock);
}
#else
@@ -378,12 +385,13 @@ void folio_activate(struct folio *folio)
{
struct lruvec *lruvec;
- if (folio_test_clear_lru(folio)) {
- lruvec = folio_lruvec_lock_irq(folio);
- folio_activate_fn(lruvec, folio);
- unlock_page_lruvec_irq(lruvec);
- folio_set_lru(folio);
- }
+ if (!folio_test_clear_lru(folio))
+ return;
+
+ lruvec = folio_lruvec_lock_irq(folio);
+ folio_activate_fn(lruvec, folio);
+ unlock_page_lruvec_irq(lruvec);
+ folio_set_lru(folio);
}
#endif
@@ -610,41 +618,41 @@ static void lru_deactivate_file_fn(struc
static void lru_deactivate_fn(struct lruvec *lruvec, struct folio *folio)
{
- if (!folio_test_unevictable(folio) && (folio_test_active(folio) || lru_gen_enabled())) {
- long nr_pages = folio_nr_pages(folio);
+ long nr_pages = folio_nr_pages(folio);
- lruvec_del_folio(lruvec, folio);
- folio_clear_active(folio);
- folio_clear_referenced(folio);
- lruvec_add_folio(lruvec, folio);
+ if (folio_test_unevictable(folio) || !(folio_test_active(folio) || lru_gen_enabled()))
+ return;
- __count_vm_events(PGDEACTIVATE, nr_pages);
- __count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE,
- nr_pages);
- }
+ lruvec_del_folio(lruvec, folio);
+ folio_clear_active(folio);
+ folio_clear_referenced(folio);
+ lruvec_add_folio(lruvec, folio);
+
+ __count_vm_events(PGDEACTIVATE, nr_pages);
+ __count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE, nr_pages);
}
static void lru_lazyfree_fn(struct lruvec *lruvec, struct folio *folio)
{
- if (folio_test_anon(folio) && folio_test_swapbacked(folio) &&
- !folio_test_swapcache(folio) && !folio_test_unevictable(folio)) {
- long nr_pages = folio_nr_pages(folio);
+ long nr_pages = folio_nr_pages(folio);
- lruvec_del_folio(lruvec, folio);
- folio_clear_active(folio);
- folio_clear_referenced(folio);
- /*
- * Lazyfree folios are clean anonymous folios. They have
- * the swapbacked flag cleared, to distinguish them from normal
- * anonymous folios
- */
- folio_clear_swapbacked(folio);
- lruvec_add_folio(lruvec, folio);
+ if (!folio_test_anon(folio) || !folio_test_swapbacked(folio) ||
+ folio_test_swapcache(folio) || folio_test_unevictable(folio))
+ return;
- __count_vm_events(PGLAZYFREE, nr_pages);
- __count_memcg_events(lruvec_memcg(lruvec), PGLAZYFREE,
- nr_pages);
- }
+ lruvec_del_folio(lruvec, folio);
+ folio_clear_active(folio);
+ folio_clear_referenced(folio);
+ /*
+ * Lazyfree folios are clean anonymous folios. They have
+ * the swapbacked flag cleared, to distinguish them from normal
+ * anonymous folios
+ */
+ folio_clear_swapbacked(folio);
+ lruvec_add_folio(lruvec, folio);
+
+ __count_vm_events(PGLAZYFREE, nr_pages);
+ __count_memcg_events(lruvec_memcg(lruvec), PGLAZYFREE, nr_pages);
}
/*
@@ -726,21 +734,21 @@ void deactivate_file_folio(struct folio
*/
void folio_deactivate(struct folio *folio)
{
- if (!folio_test_unevictable(folio) && (folio_test_active(folio) ||
- lru_gen_enabled())) {
- struct folio_batch *fbatch;
-
- folio_get(folio);
- if (!folio_test_clear_lru(folio)) {
- folio_put(folio);
- return;
- }
+ struct folio_batch *fbatch;
+
+ if (folio_test_unevictable(folio) || !(folio_test_active(folio) || lru_gen_enabled()))
+ return;
- local_lock(&cpu_fbatches.lock);
- fbatch = this_cpu_ptr(&cpu_fbatches.lru_deactivate);
- folio_batch_add_and_move(fbatch, folio, lru_deactivate_fn);
- local_unlock(&cpu_fbatches.lock);
+ folio_get(folio);
+ if (!folio_test_clear_lru(folio)) {
+ folio_put(folio);
+ return;
}
+
+ local_lock(&cpu_fbatches.lock);
+ fbatch = this_cpu_ptr(&cpu_fbatches.lru_deactivate);
+ folio_batch_add_and_move(fbatch, folio, lru_deactivate_fn);
+ local_unlock(&cpu_fbatches.lock);
}
/**
@@ -752,21 +760,22 @@ void folio_deactivate(struct folio *foli
*/
void folio_mark_lazyfree(struct folio *folio)
{
- if (folio_test_anon(folio) && folio_test_swapbacked(folio) &&
- !folio_test_swapcache(folio) && !folio_test_unevictable(folio)) {
- struct folio_batch *fbatch;
-
- folio_get(folio);
- if (!folio_test_clear_lru(folio)) {
- folio_put(folio);
- return;
- }
+ struct folio_batch *fbatch;
- local_lock(&cpu_fbatches.lock);
- fbatch = this_cpu_ptr(&cpu_fbatches.lru_lazyfree);
- folio_batch_add_and_move(fbatch, folio, lru_lazyfree_fn);
- local_unlock(&cpu_fbatches.lock);
+ if (!folio_test_anon(folio) || !folio_test_swapbacked(folio) ||
+ folio_test_swapcache(folio) || folio_test_unevictable(folio))
+ return;
+
+ folio_get(folio);
+ if (!folio_test_clear_lru(folio)) {
+ folio_put(folio);
+ return;
}
+
+ local_lock(&cpu_fbatches.lock);
+ fbatch = this_cpu_ptr(&cpu_fbatches.lru_lazyfree);
+ folio_batch_add_and_move(fbatch, folio, lru_lazyfree_fn);
+ local_unlock(&cpu_fbatches.lock);
}
void lru_add_drain(void)
_
Patches currently in -mm which might be from yuzhao@xxxxxxxxxx are
mm-hugetlb_vmemmap-dont-synchronize_rcu-without-hvo.patch
mm-swap-reduce-indentation-level.patch
mm-swap-rename-cpu_fbatches-activate.patch
mm-swap-fold-lru_rotate-into-cpu_fbatches.patch
mm-swap-remove-remaining-_fn-suffix.patch
mm-swap-remove-boilerplate.patch
