The patch titled
Subject: tools/lib/list_sort: remove redundant code for cond_resched handling
has been added to the -mm mm-nonmm-unstable branch. Its filename is
tools-lib-list_sort-remove-redundant-code-for-cond_resched-handling.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/tools-lib-list_sort-remove-redundant-code-for-cond_resched-handling.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Kuan-Wei Chiu <visitorckw@xxxxxxxxx>
Subject: tools/lib/list_sort: remove redundant code for cond_resched handling
Date: Sun, 26 May 2024 07:02:06 +0800
Since cond_resched() is not called in userspace, remove the redundant code
in userspace's list_sort() implementation. This change eliminates the
unused 'count' variable and the associated logic for invoking cmp()
periodically, which was intended to trigger cond_resched() in kernel
space.
The removed code includes:
- Declaration and increment of the 'count' variable.
- Conditional invocation of cmp() based on 'count'.
This cleanup simplifies merge_final(), avoids unnecessary overhead, and
has no impact on the functionality of list_sort() in userspace.
Link: https://lkml.kernel.org/r/20240525230206.1077536-1-visitorckw@xxxxxxxxx
Signed-off-by: Kuan-Wei Chiu <visitorckw@xxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Ching-Chun (Jim) Huang <jserv@xxxxxxxxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
tools/lib/list_sort.c | 10 ----------
1 file changed, 10 deletions(-)
--- a/tools/lib/list_sort.c~tools-lib-list_sort-remove-redundant-code-for-cond_resched-handling
+++ a/tools/lib/list_sort.c
@@ -52,7 +52,6 @@ static void merge_final(void *priv, list
struct list_head *a, struct list_head *b)
{
struct list_head *tail = head;
- u8 count = 0;
for (;;) {
/* if equal, take 'a' -- important for sort stability */
@@ -78,15 +77,6 @@ static void merge_final(void *priv, list
/* Finish linking remainder of list b on to tail */
tail->next = b;
do {
- /*
- * If the merge is highly unbalanced (e.g. the input is
- * already sorted), this loop may run many iterations.
- * Continue callbacks to the client even though no
- * element comparison is needed, so the client's cmp()
- * routine can invoke cond_resched() periodically.
- */
- if (unlikely(!++count))
- cmp(priv, b, b);
b->prev = tail;
tail = b;
b = b->next;
_
Patches currently in -mm which might be from visitorckw@xxxxxxxxx are
perf-core-fix-several-typos.patch
bcache-fix-typo.patch
bcachefs-fix-typo.patch
lib-min_heap-add-type-safe-interface.patch
lib-min_heap-add-min_heap_init.patch
lib-min_heap-add-min_heap_peek.patch
lib-min_heap-add-min_heap_full.patch
lib-min_heap-add-args-for-min_heap_callbacks.patch
lib-min_heap-add-min_heap_sift_up.patch
lib-min_heap-add-min_heap_del.patch
lib-min_heap-update-min_heap_push-and-min_heap_pop-to-return-bool-values.patch
lib-min_heap-rename-min_heapify-to-min_heap_sift_down.patch
lib-min_heap-update-min_heap_push-to-use-min_heap_sift_up.patch
lib-test_min_heap-add-test-for-heap_del.patch
bcache-remove-heap-related-macros-and-switch-to-generic-min_heap.patch
bcachefs-remove-heap-related-macros-and-switch-to-generic-min_heap.patch
lib-sort-remove-unused-pr_fmt-macro.patch
lib-sort-fix-outdated-comment-regarding-glibc-qsort.patch
lib-sort-optimize-heapsort-for-handling-final-2-or-3-elements.patch
lib-test_sort-add-a-testcase-to-ensure-code-coverage.patch
tools-lib-list_sort-remove-redundant-code-for-cond_resched-handling.patch
