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authorLinus Torvalds <torvalds@linux-foundation.org>2021-06-29 17:29:11 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-06-29 17:29:11 -0700
commit65090f30ab791810a3dc840317e57df05018559c (patch)
treef417526656da37109777e89613e140ffc59228bc /kernel/kthread.c
parent349a2d52ffe59b7a0c5876fa7ee9f3eaf188b830 (diff)
parent0ed950d1f28142ccd9a9453c60df87853530d778 (diff)
downloadlinux-65090f30ab791810a3dc840317e57df05018559c.tar.bz2
Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton: "191 patches. Subsystems affected by this patch series: kthread, ia64, scripts, ntfs, squashfs, ocfs2, kernel/watchdog, and mm (gup, pagealloc, slab, slub, kmemleak, dax, debug, pagecache, gup, swap, memcg, pagemap, mprotect, bootmem, dma, tracing, vmalloc, kasan, initialization, pagealloc, and memory-failure)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (191 commits) mm,hwpoison: make get_hwpoison_page() call get_any_page() mm,hwpoison: send SIGBUS with error virutal address mm/page_alloc: split pcp->high across all online CPUs for cpuless nodes mm/page_alloc: allow high-order pages to be stored on the per-cpu lists mm: replace CONFIG_FLAT_NODE_MEM_MAP with CONFIG_FLATMEM mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA docs: remove description of DISCONTIGMEM arch, mm: remove stale mentions of DISCONIGMEM mm: remove CONFIG_DISCONTIGMEM m68k: remove support for DISCONTIGMEM arc: remove support for DISCONTIGMEM arc: update comment about HIGHMEM implementation alpha: remove DISCONTIGMEM and NUMA mm/page_alloc: move free_the_page mm/page_alloc: fix counting of managed_pages mm/page_alloc: improve memmap_pages dbg msg mm: drop SECTION_SHIFT in code comments mm/page_alloc: introduce vm.percpu_pagelist_high_fraction mm/page_alloc: limit the number of pages on PCP lists when reclaim is active mm/page_alloc: scale the number of pages that are batch freed ...
Diffstat (limited to 'kernel/kthread.c')
-rw-r--r--kernel/kthread.c19
1 files changed, 12 insertions, 7 deletions
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 6b0a30a944b3..5b37a8567168 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -1162,14 +1162,14 @@ static bool __kthread_cancel_work(struct kthread_work *work)
* modify @dwork's timer so that it expires after @delay. If @delay is zero,
* @work is guaranteed to be queued immediately.
*
- * Return: %true if @dwork was pending and its timer was modified,
- * %false otherwise.
+ * Return: %false if @dwork was idle and queued, %true otherwise.
*
* A special case is when the work is being canceled in parallel.
* It might be caused either by the real kthread_cancel_delayed_work_sync()
* or yet another kthread_mod_delayed_work() call. We let the other command
- * win and return %false here. The caller is supposed to synchronize these
- * operations a reasonable way.
+ * win and return %true here. The return value can be used for reference
+ * counting and the number of queued works stays the same. Anyway, the caller
+ * is supposed to synchronize these operations a reasonable way.
*
* This function is safe to call from any context including IRQ handler.
* See __kthread_cancel_work() and kthread_delayed_work_timer_fn()
@@ -1181,13 +1181,15 @@ bool kthread_mod_delayed_work(struct kthread_worker *worker,
{
struct kthread_work *work = &dwork->work;
unsigned long flags;
- int ret = false;
+ int ret;
raw_spin_lock_irqsave(&worker->lock, flags);
/* Do not bother with canceling when never queued. */
- if (!work->worker)
+ if (!work->worker) {
+ ret = false;
goto fast_queue;
+ }
/* Work must not be used with >1 worker, see kthread_queue_work() */
WARN_ON_ONCE(work->worker != worker);
@@ -1205,8 +1207,11 @@ bool kthread_mod_delayed_work(struct kthread_worker *worker,
* be used for reference counting.
*/
kthread_cancel_delayed_work_timer(work, &flags);
- if (work->canceling)
+ if (work->canceling) {
+ /* The number of works in the queue does not change. */
+ ret = true;
goto out;
+ }
ret = __kthread_cancel_work(work);
fast_queue: