The patch titled Subject: workqueue: make alloc_workqueue() take printf fmt and args for name has been added to the -mm tree. Its filename is workqueue-make-alloc_workqueue-take-printf-fmt-and-args-for-name.patch 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/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ From: Tejun Heo <tj@xxxxxxxxxx> Subject: workqueue: make alloc_workqueue() take printf fmt and args for name alloc_workqueue() currently expects the passed in @name pointer to remain accessible. This is inconvenient and a bit silly given that the whole wq is being dynamically allocated. This patch updates alloc_workqueue() and friends to take printf format string instead of opaque string and matching varargs at the end. The name is allocated together with the wq and formatted. alloc_ordered_workqueue() is converted to a macro to unify varargs handling with alloc_workqueue(), and, while at it, add comment to alloc_workqueue(). None of the current in-kernel users pass in string with '%' as constant name and this change shouldn't cause any problem. Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Suggested-by: Christoph Hellwig <hch@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <> --- include/linux/workqueue.h | 48 ++++++++++++++++++++++++------------ kernel/workqueue.c | 32 ++++++++++++++++-------- 2 files changed, 54 insertions(+), 26 deletions(-) diff -puN include/linux/workqueue.h~workqueue-make-alloc_workqueue-take-printf-fmt-and-args-for-name include/linux/workqueue.h --- a/include/linux/workqueue.h~workqueue-make-alloc_workqueue-take-printf-fmt-and-args-for-name +++ a/include/linux/workqueue.h @@ -297,32 +297,51 @@ extern struct workqueue_struct *system_u extern struct workqueue_struct *system_freezable_wq; extern struct workqueue_struct * -__alloc_workqueue_key(const char *name, unsigned int flags, int max_active, - struct lock_class_key *key, const char *lock_name); +__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active, + struct lock_class_key *key, const char *lock_name, ...) + __attribute__((format (printf, 1, 6))); +/** + * alloc_workqueue - allocate a workqueue + * @fmt: printf format for the name of the workqueue + * @flags: WQ_* flags + * @max_active: max in-flight work items, 0 for default + * @args: args for @fmt + * + * Allocate a workqueue with the specified parameters. For detailed + * information on WQ_* flags, please refer to Documentation/workqueue.txt. + * + * The __lock_name macro dance is to guarantee that single lock_class_key + * doesn't end up with different namesm, which isn't allowed by lockdep. + * + * RETURNS: + * Pointer to the allocated workqueue on success, %NULL on failure. + */ #ifdef CONFIG_LOCKDEP -#define alloc_workqueue(name, flags, max_active) \ +#define alloc_workqueue(fmt, flags, max_active, args...) \ ({ \ static struct lock_class_key __key; \ const char *__lock_name; \ \ - if (__builtin_constant_p(name)) \ - __lock_name = (name); \ + if (__builtin_constant_p(fmt)) \ + __lock_name = (fmt); \ else \ - __lock_name = #name; \ + __lock_name = #fmt; \ \ - __alloc_workqueue_key((name), (flags), (max_active), \ - &__key, __lock_name); \ + __alloc_workqueue_key((fmt), (flags), (max_active), \ + &__key, __lock_name, ##args); \ }) #else -#define alloc_workqueue(name, flags, max_active) \ - __alloc_workqueue_key((name), (flags), (max_active), NULL, NULL) +#define alloc_workqueue(fmt, flags, max_active, args...) \ + __alloc_workqueue_key((fmt), (flags), (max_active), \ + NULL, NULL, ##args) #endif /** * alloc_ordered_workqueue - allocate an ordered workqueue - * @name: name of the workqueue + * @fmt: printf format for the name of the workqueue * @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful) + * @args: args for @fmt * * Allocate an ordered workqueue. An ordered workqueue executes at * most one work item at any given time in the queued order. They are @@ -331,11 +350,8 @@ __alloc_workqueue_key(const char *name, * RETURNS: * Pointer to the allocated workqueue on success, %NULL on failure. */ -static inline struct workqueue_struct * -alloc_ordered_workqueue(const char *name, unsigned int flags) -{ - return alloc_workqueue(name, WQ_UNBOUND | flags, 1); -} +#define alloc_ordered_workqueue(fmt, flags, args...) \ + alloc_workqueue(fmt, WQ_UNBOUND | (flags), 1, ##args) #define create_workqueue(name) \ alloc_workqueue((name), WQ_MEM_RECLAIM, 1) diff -puN kernel/workqueue.c~workqueue-make-alloc_workqueue-take-printf-fmt-and-args-for-name kernel/workqueue.c --- a/kernel/workqueue.c~workqueue-make-alloc_workqueue-take-printf-fmt-and-args-for-name +++ a/kernel/workqueue.c @@ -242,10 +242,10 @@ struct workqueue_struct { int nr_drainers; /* W: drain in progress */ int saved_max_active; /* W: saved cwq max_active */ - const char *name; /* I: workqueue name */ #ifdef CONFIG_LOCKDEP struct lockdep_map lockdep_map; #endif + char name[]; /* I: workqueue name */ }; struct workqueue_struct *system_wq __read_mostly; @@ -2954,14 +2954,29 @@ static int wq_clamp_max_active(int max_a return clamp_val(max_active, 1, lim); } -struct workqueue_struct *__alloc_workqueue_key(const char *name, +struct workqueue_struct *__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active, struct lock_class_key *key, - const char *lock_name) + const char *lock_name, ...) { + va_list args, args1; struct workqueue_struct *wq; unsigned int cpu; + size_t namelen; + + /* determine namelen, allocate wq and format name */ + va_start(args, lock_name); + va_copy(args1, args); + namelen = vsnprintf(NULL, 0, fmt, args) + 1; + + wq = kzalloc(sizeof(*wq) + namelen, GFP_KERNEL); + if (!wq) + goto err; + + vsnprintf(wq->name, namelen, fmt, args1); + va_end(args); + va_end(args1); /* * Workqueues which may be used during memory reclaim should @@ -2978,12 +2993,9 @@ struct workqueue_struct *__alloc_workque flags |= WQ_HIGHPRI; max_active = max_active ?: WQ_DFL_ACTIVE; - max_active = wq_clamp_max_active(max_active, flags, name); - - wq = kzalloc(sizeof(*wq), GFP_KERNEL); - if (!wq) - goto err; + max_active = wq_clamp_max_active(max_active, flags, wq->name); + /* init wq */ wq->flags = flags; wq->saved_max_active = max_active; mutex_init(&wq->flush_mutex); @@ -2991,7 +3003,6 @@ struct workqueue_struct *__alloc_workque INIT_LIST_HEAD(&wq->flusher_queue); INIT_LIST_HEAD(&wq->flusher_overflow); - wq->name = name; lockdep_init_map(&wq->lockdep_map, lock_name, key, 0); INIT_LIST_HEAD(&wq->list); @@ -3020,7 +3031,8 @@ struct workqueue_struct *__alloc_workque if (!rescuer) goto err; - rescuer->task = kthread_create(rescuer_thread, wq, "%s", name); + rescuer->task = kthread_create(rescuer_thread, wq, "%s", + wq->name); if (IS_ERR(rescuer->task)) goto err; _ Subject: Subject: workqueue: make alloc_workqueue() take printf fmt and args for name Patches currently in -mm which might be from tj@xxxxxxxxxx are origin.patch linux-next.patch drivers-scsi-osd-osd_uldc-use-ida_simple_get-to-handle-id.patch procfs-make-proc_get_link-to-use-dentry-instead-of-inode.patch procfs-introduce-the-proc-pid-map_files-directory.patch workqueue-make-alloc_workqueue-take-printf-fmt-and-args-for-name.patch scatterlist-new-helper-functions.patch scatterlist-new-helper-functions-update.patch scatterlist-new-helper-functions-update-fix.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html