From 704bc669e1dda3eb8f6d5cb462b21e85558a3912 Mon Sep 17 00:00:00 2001 From: Jungseung Lee Date: Mon, 20 Mar 2023 12:29:05 +0900 Subject: 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 + 1 file changed, 1 insertion(+) (limited to 'include/linux/workqueue.h') 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); -- cgit From afa4bb778e48d79e4a642ed41e3b4e0de7489a6c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 23 Jun 2023 12:08:14 -0700 Subject: workqueue: clean up WORK_* constant types, clarify masking MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Dave Airlie reports that gcc-13.1.1 has started complaining about some of the workqueue code in 32-bit arm builds: kernel/workqueue.c: In function ‘get_work_pwq’: kernel/workqueue.c:713:24: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] 713 | return (void *)(data & WORK_STRUCT_WQ_DATA_MASK); | ^ [ ... a couple of other cases ... ] and while it's not immediately clear exactly why gcc started complaining about it now, I suspect it's some C23-induced enum type handlign fixup in gcc-13 is the cause. Whatever the reason for starting to complain, the code and data types are indeed disgusting enough that the complaint is warranted. The wq code ends up creating various "helper constants" (like that WORK_STRUCT_WQ_DATA_MASK) using an enum type, which is all kinds of confused. The mask needs to be 'unsigned long', not some unspecified enum type. To make matters worse, the actual "mask and cast to a pointer" is repeated a couple of times, and the cast isn't even always done to the right pointer, but - as the error case above - to a 'void *' with then the compiler finishing the job. That's now how we roll in the kernel. So create the masks using the proper types rather than some ambiguous enumeration, and use a nice helper that actually does the type conversion in one well-defined place. Incidentally, this magically makes clang generate better code. That, admittedly, is really just a sign of clang having been seriously confused before, and cleaning up the typing unconfuses the compiler too. Reported-by: Dave Airlie Link: https://lore.kernel.org/lkml/CAPM=9twNnV4zMCvrPkw3H-ajZOH-01JVh_kDrxdPYQErz8ZTdA@mail.gmail.com/ Cc: Arnd Bergmann Cc: Tejun Heo Cc: Nick Desaulniers Cc: Nathan Chancellor Signed-off-by: Linus Torvalds --- include/linux/workqueue.h | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) (limited to 'include/linux/workqueue.h') diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index 3992c994787f..683efe29fa69 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -68,7 +68,6 @@ enum { WORK_OFFQ_FLAG_BASE = WORK_STRUCT_COLOR_SHIFT, __WORK_OFFQ_CANCELING = WORK_OFFQ_FLAG_BASE, - WORK_OFFQ_CANCELING = (1 << __WORK_OFFQ_CANCELING), /* * When a work item is off queue, its high bits point to the last @@ -79,12 +78,6 @@ enum { WORK_OFFQ_POOL_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS, WORK_OFFQ_LEFT = BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT, WORK_OFFQ_POOL_BITS = WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31, - WORK_OFFQ_POOL_NONE = (1LU << WORK_OFFQ_POOL_BITS) - 1, - - /* convenience constants */ - WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1, - WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK, - WORK_STRUCT_NO_POOL = (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT, /* bit mask for work_busy() return values */ WORK_BUSY_PENDING = 1 << 0, @@ -94,6 +87,14 @@ enum { WORKER_DESC_LEN = 24, }; +/* Convenience constants - of type 'unsigned long', not 'enum'! */ +#define WORK_OFFQ_CANCELING (1ul << __WORK_OFFQ_CANCELING) +#define WORK_OFFQ_POOL_NONE ((1ul << WORK_OFFQ_POOL_BITS) - 1) +#define WORK_STRUCT_NO_POOL (WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT) + +#define WORK_STRUCT_FLAG_MASK ((1ul << WORK_STRUCT_FLAG_BITS) - 1) +#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK) + struct work_struct { atomic_long_t data; struct list_head entry; -- cgit