Device nodes accessed via of_get_compatible_child() require
of_node_put() to be called when the node is no longer required to avoid
leaving a reference to the node behind, leaking the resource.
In this case, the usage of 'tnode' is straightforward and there are no
error paths, allowing for a single of_node_put() when 'tnode' is no
longer required.
Cc: stable(a)vger.kernel.org
Fixes: 29646ee33cc3 ("counter: stm32-timer-cnt: add checks on quadrature encoder capability")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz(a)gmail.com>
---
drivers/counter/stm32-timer-cnt.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c
index 186e73d6ccb4..0d8206adccb3 100644
--- a/drivers/counter/stm32-timer-cnt.c
+++ b/drivers/counter/stm32-timer-cnt.c
@@ -694,6 +694,7 @@ static int stm32_timer_cnt_probe_encoder(struct device *dev,
}
ret = of_property_read_u32(tnode, "reg", &idx);
+ of_node_put(tnode);
if (ret) {
dev_err(dev, "Can't get index (%d)\n", ret);
return ret;
---
base-commit: a39230ecf6b3057f5897bc4744a790070cfbe7a8
change-id: 20241027-stm32-timer-cnt-of_node_put-8c6695e7a373
Best regards,
--
Javier Carrasco <javier.carrasco.cruz(a)gmail.com>
The patch titled
Subject: mm/damon/core: avoid overflow in damon_feed_loop_next_input()
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-damon-core-avoid-overflow-in-damon_feed_loop_next_input.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-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: SeongJae Park <sj(a)kernel.org>
Subject: mm/damon/core: avoid overflow in damon_feed_loop_next_input()
Date: Thu, 31 Oct 2024 09:12:03 -0700
damon_feed_loop_next_input() is inefficient and fragile to overflows.
Specifically, 'score_goal_diff_bp' calculation can overflow when 'score'
is high. The calculation is actually unnecessary at all because 'goal' is
a constant of value 10,000. Calculation of 'compensation' is again
fragile to overflow. Final calculation of return value for under-achiving
case is again fragile to overflow when the current score is
under-achieving the target.
Add two corner cases handling at the beginning of the function to make the
body easier to read, and rewrite the body of the function to avoid
overflows and the unnecessary bp value calcuation.
Link: https://lkml.kernel.org/r/20241031161203.47751-1-sj@kernel.org
Fixes: 9294a037c015 ("mm/damon/core: implement goal-oriented feedback-driven quota auto-tuning")
Signed-off-by: SeongJae Park <sj(a)kernel.org>
Reported-by: Guenter Roeck <linux(a)roeck-us.net>
Closes: https://lore.kernel.org/944f3d5b-9177-48e7-8ec9-7f1331a3fea3@roeck-us.net
Tested-by: Guenter Roeck <linux(a)roeck-us.net>
Cc: <stable(a)vger.kernel.org> [6.8.x]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/damon/core.c | 28 +++++++++++++++++++++-------
1 file changed, 21 insertions(+), 7 deletions(-)
--- a/mm/damon/core.c~mm-damon-core-avoid-overflow-in-damon_feed_loop_next_input
+++ a/mm/damon/core.c
@@ -1456,17 +1456,31 @@ static unsigned long damon_feed_loop_nex
unsigned long score)
{
const unsigned long goal = 10000;
- unsigned long score_goal_diff = max(goal, score) - min(goal, score);
- unsigned long score_goal_diff_bp = score_goal_diff * 10000 / goal;
- unsigned long compensation = last_input * score_goal_diff_bp / 10000;
/* Set minimum input as 10000 to avoid compensation be zero */
const unsigned long min_input = 10000;
+ unsigned long score_goal_diff, compensation;
+ bool over_achieving = score > goal;
- if (goal > score)
+ if (score == goal)
+ return last_input;
+ if (score >= goal * 2)
+ return min_input;
+
+ if (over_achieving)
+ score_goal_diff = score - goal;
+ else
+ score_goal_diff = goal - score;
+
+ if (last_input < ULONG_MAX / score_goal_diff)
+ compensation = last_input * score_goal_diff / goal;
+ else
+ compensation = last_input / goal * score_goal_diff;
+
+ if (over_achieving)
+ return max(last_input - compensation, min_input);
+ if (last_input < ULONG_MAX - compensation)
return last_input + compensation;
- if (last_input > compensation + min_input)
- return last_input - compensation;
- return min_input;
+ return ULONG_MAX;
}
#ifdef CONFIG_PSI
_
Patches currently in -mm which might be from sj(a)kernel.org are
mm-damon-core-handle-zero-aggregationops_update-intervals.patch
mm-damon-core-handle-zero-schemes-apply-interval.patch
mm-damon-core-avoid-overflow-in-damon_feed_loop_next_input.patch
selftests-damon-huge_count_read_write-remove-unnecessary-debugging-message.patch
selftests-damon-_debugfs_common-hide-expected-error-message-from-test_write_result.patch
selftests-damon-debugfs_duplicate_context_creation-hide-errors-from-expected-file-write-failures.patch
mm-damon-kconfig-update-dbgfs_kunit-prompt-copy-for-sysfs_kunit.patch
mm-damon-tests-dbgfs-kunit-fix-the-header-double-inclusion-guarding-ifdef-comment.patch
The patch titled
Subject: mm: multi-gen LRU: remove MM_LEAF_OLD and MM_NONLEAF_TOTAL stats
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-multi-gen-lru-remove-mm_leaf_old-and-mm_nonleaf_total-stats.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-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(a)google.com>
Subject: mm: multi-gen LRU: remove MM_LEAF_OLD and MM_NONLEAF_TOTAL stats
Date: Sat, 19 Oct 2024 01:29:38 +0000
Patch series "mm: multi-gen LRU: Have secondary MMUs participate in
MM_WALK".
Today, the MM_WALK capability causes MGLRU to clear the young bit from
PMDs and PTEs during the page table walk before eviction, but MGLRU does
not call the clear_young() MMU notifier in this case. By not calling this
notifier, the MM walk takes less time/CPU, but it causes pages that are
accessed mostly through KVM / secondary MMUs to appear younger than they
should be.
We do call the clear_young() notifier today, but only when attempting to
evict the page, so we end up clearing young/accessed information less
frequently for secondary MMUs than for mm PTEs, and therefore they appear
younger and are less likely to be evicted. Therefore, memory that is
*not* being accessed mostly by KVM will be evicted *more* frequently,
worsening performance.
ChromeOS observed a tab-open latency regression when enabling MGLRU with a
setup that involved running a VM:
Tab-open latency histogram (ms)
Version p50 mean p95 p99 max
base 1315 1198 2347 3454 10319
mglru 2559 1311 7399 12060 43758
fix 1119 926 2470 4211 6947
This series replaces the final non-selftest patchs from this series[1],
which introduced a similar change (and a new MMU notifier) with KVM
optimizations. I'll send a separate series (to Sean and Paolo) for the
KVM optimizations.
This series also makes proactive reclaim with MGLRU possible for KVM
memory. I have verified that this functions correctly with the selftest
from [1], but given that that test is a KVM selftest, I'll send it with
the rest of the KVM optimizations later. Andrew, let me know if you'd
like to take the test now anyway.
[1]: https://lore.kernel.org/linux-mm/20240926013506.860253-18-jthoughton@google…
This patch (of 2):
The removed stats, MM_LEAF_OLD and MM_NONLEAF_TOTAL, are not very helpful
and become more complicated to properly compute when adding
test/clear_young() notifiers in MGLRU's mm walk.
Link: https://lkml.kernel.org/r/20241019012940.3656292-1-jthoughton@google.com
Link: https://lkml.kernel.org/r/20241019012940.3656292-2-jthoughton@google.com
Fixes: bd74fdaea146 ("mm: multi-gen LRU: support page table walks")
Signed-off-by: Yu Zhao <yuzhao(a)google.com>
Signed-off-by: James Houghton <jthoughton(a)google.com>
Cc: Axel Rasmussen <axelrasmussen(a)google.com>
Cc: David Matlack <dmatlack(a)google.com>
Cc: David Rientjes <rientjes(a)google.com>
Cc: David Stevens <stevensd(a)google.com>
Cc: Oliver Upton <oliver.upton(a)linux.dev>
Cc: Paolo Bonzini <pbonzini(a)redhat.com>
Cc: Sean Christopherson <seanjc(a)google.com>
Cc: Wei Xu <weixugc(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
include/linux/mmzone.h | 2 --
mm/vmscan.c | 14 +++++---------
2 files changed, 5 insertions(+), 11 deletions(-)
--- a/include/linux/mmzone.h~mm-multi-gen-lru-remove-mm_leaf_old-and-mm_nonleaf_total-stats
+++ a/include/linux/mmzone.h
@@ -458,9 +458,7 @@ struct lru_gen_folio {
enum {
MM_LEAF_TOTAL, /* total leaf entries */
- MM_LEAF_OLD, /* old leaf entries */
MM_LEAF_YOUNG, /* young leaf entries */
- MM_NONLEAF_TOTAL, /* total non-leaf entries */
MM_NONLEAF_FOUND, /* non-leaf entries found in Bloom filters */
MM_NONLEAF_ADDED, /* non-leaf entries added to Bloom filters */
NR_MM_STATS
--- a/mm/vmscan.c~mm-multi-gen-lru-remove-mm_leaf_old-and-mm_nonleaf_total-stats
+++ a/mm/vmscan.c
@@ -3399,7 +3399,6 @@ restart:
continue;
if (!pte_young(ptent)) {
- walk->mm_stats[MM_LEAF_OLD]++;
continue;
}
@@ -3552,7 +3551,6 @@ restart:
walk->mm_stats[MM_LEAF_TOTAL]++;
if (!pmd_young(val)) {
- walk->mm_stats[MM_LEAF_OLD]++;
continue;
}
@@ -3564,8 +3562,6 @@ restart:
continue;
}
- walk->mm_stats[MM_NONLEAF_TOTAL]++;
-
if (!walk->force_scan && should_clear_pmd_young()) {
if (!pmd_young(val))
continue;
@@ -5254,11 +5250,11 @@ static void lru_gen_seq_show_full(struct
for (tier = 0; tier < MAX_NR_TIERS; tier++) {
seq_printf(m, " %10d", tier);
for (type = 0; type < ANON_AND_FILE; type++) {
- const char *s = " ";
+ const char *s = "xxx";
unsigned long n[3] = {};
if (seq == max_seq) {
- s = "RT ";
+ s = "RTx";
n[0] = READ_ONCE(lrugen->avg_refaulted[type][tier]);
n[1] = READ_ONCE(lrugen->avg_total[type][tier]);
} else if (seq == min_seq[type] || NR_HIST_GENS > 1) {
@@ -5280,14 +5276,14 @@ static void lru_gen_seq_show_full(struct
seq_puts(m, " ");
for (i = 0; i < NR_MM_STATS; i++) {
- const char *s = " ";
+ const char *s = "xxxx";
unsigned long n = 0;
if (seq == max_seq && NR_HIST_GENS == 1) {
- s = "LOYNFA";
+ s = "TYFA";
n = READ_ONCE(mm_state->stats[hist][i]);
} else if (seq != max_seq && NR_HIST_GENS > 1) {
- s = "loynfa";
+ s = "tyfa";
n = READ_ONCE(mm_state->stats[hist][i]);
}
_
Patches currently in -mm which might be from yuzhao(a)google.com are
mm-multi-gen-lru-remove-mm_leaf_old-and-mm_nonleaf_total-stats.patch
mm-multi-gen-lru-use-pteppmdp_clear_young_notify.patch
mm-page_alloc-keep-track-of-free-highatomic.patch