From 704bc669e1dda3eb8f6d5cb462b21e85558a3912 Mon Sep 17 00:00:00 2001 From: Jungseung Lee Date: Mon, 20 Mar 2023 12:29:05 +0900 Subject: [PATCH] workqueue: Introduce show_freezable_workqueues Currently show_all_workqueue is called if freeze fails at the time of freeze the workqueues, which shows the status of all workqueues and of all worker pools. In this cases we may only need to dump state of only workqueues that are freezable and busy. This patch defines show_freezable_workqueues, which uses show_one_workqueue, a granular function that shows the state of individual workqueues, so that dump only the state of freezable workqueues at that time. tj: Minor message adjustment. Signed-off-by: Jungseung Lee Signed-off-by: Tejun Heo --- include/linux/workqueue.h | 1 + kernel/power/process.c | 2 +- kernel/workqueue.c | 26 ++++++++++++++++++++++++-- 3 files changed, 26 insertions(+), 3 deletions(-) diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index ac551b8ee7d9..3992c994787f 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -472,6 +472,7 @@ extern unsigned int work_busy(struct work_struct *work); extern __printf(1, 2) void set_worker_desc(const char *fmt, ...); extern void print_worker_info(const char *log_lvl, struct task_struct *task); extern void show_all_workqueues(void); +extern void show_freezable_workqueues(void); extern void show_one_workqueue(struct workqueue_struct *wq); extern void wq_worker_comm(char *buf, size_t size, struct task_struct *task); diff --git a/kernel/power/process.c b/kernel/power/process.c index 6c1c7e566d35..cae81a87cc91 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -93,7 +93,7 @@ static int try_to_freeze_tasks(bool user_only) todo - wq_busy, wq_busy); if (wq_busy) - show_all_workqueues(); + show_freezable_workqueues(); if (!wakeup || pm_debug_messages_on) { read_lock(&tasklist_lock); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 044b4eee760b..d78935e4fb5d 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -5065,8 +5065,7 @@ next_pool: /** * show_all_workqueues - dump workqueue state * - * Called from a sysrq handler or try_to_freeze_tasks() and prints out - * all busy workqueues and pools. + * Called from a sysrq handler and prints out all busy workqueues and pools. */ void show_all_workqueues(void) { @@ -5087,6 +5086,29 @@ void show_all_workqueues(void) rcu_read_unlock(); } +/** + * show_freezable_workqueues - dump freezable workqueue state + * + * Called from try_to_freeze_tasks() and prints out all freezable workqueues + * still busy. + */ +void show_freezable_workqueues(void) +{ + struct workqueue_struct *wq; + + rcu_read_lock(); + + pr_info("Showing freezable workqueues that are still busy:\n"); + + list_for_each_entry_rcu(wq, &workqueues, list) { + if (!(wq->flags & WQ_FREEZABLE)) + continue; + show_one_workqueue(wq); + } + + rcu_read_unlock(); +} + /* used to show worker information through /proc/PID/{comm,stat,status} */ void wq_worker_comm(char *buf, size_t size, struct task_struct *task) { -- 2.34.1