From 2ff8f9a3b11ff0f9ae9d8713754e077a2231de09 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Fri, 27 Sep 2024 00:49:06 +0200 Subject: [PATCH] kthread: Unify kthread_create_on_cpu() and kthread_create_worker_on_cpu() automatic format kthread_create_on_cpu() uses the CPU argument as an implicit and unique printf argument to add to the format whereas kthread_create_worker_on_cpu() still relies on explicitly passing the printf arguments. This difference in behaviour is error prone and doesn't help standardizing per-CPU kthread names. Unify the behaviours and convert kthread_create_worker_on_cpu() to use the printf behaviour of kthread_create_on_cpu(). Signed-off-by: Frederic Weisbecker --- fs/erofs/zdata.c | 2 +- include/linux/kthread.h | 21 +++++++++++---- kernel/kthread.c | 59 ++++++++++++++++++++++++----------------- 3 files changed, 52 insertions(+), 30 deletions(-) diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index 01f147505487..a23392327ce2 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -320,7 +320,7 @@ static void erofs_destroy_percpu_workers(void) static struct kthread_worker *erofs_init_percpu_worker(int cpu) { struct kthread_worker *worker = - kthread_create_worker_on_cpu(cpu, 0, "erofs_worker/%u", cpu); + kthread_create_worker_on_cpu(cpu, 0, "erofs_worker/%u"); if (IS_ERR(worker)) return worker; diff --git a/include/linux/kthread.h b/include/linux/kthread.h index 30209bdf83a2..0c66e7c1092a 100644 --- a/include/linux/kthread.h +++ b/include/linux/kthread.h @@ -187,13 +187,24 @@ extern void __kthread_init_worker(struct kthread_worker *worker, int kthread_worker_fn(void *worker_ptr); -__printf(2, 3) -struct kthread_worker * -kthread_create_worker(unsigned int flags, const char namefmt[], ...); +__printf(3, 4) +struct kthread_worker *kthread_create_worker_on_node(unsigned int flags, + int node, + const char namefmt[], ...); -__printf(3, 4) struct kthread_worker * +#define kthread_create_worker(flags, namefmt, ...) \ +({ \ + struct kthread_worker *__kw \ + = kthread_create_worker_on_node(flags, NUMA_NO_NODE, \ + namefmt, ## __VA_ARGS__); \ + if (!IS_ERR(__kw)) \ + wake_up_process(__kw->task); \ + __kw; \ +}) + +struct kthread_worker * kthread_create_worker_on_cpu(int cpu, unsigned int flags, - const char namefmt[], ...); + const char namefmt[]); bool kthread_queue_work(struct kthread_worker *worker, struct kthread_work *work); diff --git a/kernel/kthread.c b/kernel/kthread.c index 32d620a99f11..2d52126d5da0 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -1030,12 +1030,11 @@ int kthread_worker_fn(void *worker_ptr) EXPORT_SYMBOL_GPL(kthread_worker_fn); static __printf(3, 0) struct kthread_worker * -__kthread_create_worker(int cpu, unsigned int flags, - const char namefmt[], va_list args) +__kthread_create_worker_on_node(unsigned int flags, int node, + const char namefmt[], va_list args) { struct kthread_worker *worker; struct task_struct *task; - int node = NUMA_NO_NODE; worker = kzalloc(sizeof(*worker), GFP_KERNEL); if (!worker) @@ -1043,20 +1042,14 @@ __kthread_create_worker(int cpu, unsigned int flags, kthread_init_worker(worker); - if (cpu >= 0) - node = cpu_to_node(cpu); - task = __kthread_create_on_node(kthread_worker_fn, worker, - node, namefmt, args); + node, namefmt, args); if (IS_ERR(task)) goto fail_task; - if (cpu >= 0) - kthread_bind(task, cpu); - worker->flags = flags; worker->task = task; - wake_up_process(task); + return worker; fail_task: @@ -1067,6 +1060,7 @@ __kthread_create_worker(int cpu, unsigned int flags, /** * kthread_create_worker - create a kthread worker * @flags: flags modifying the default behavior of the worker + * @node: task structure for the thread is allocated on this node * @namefmt: printf-style name for the kthread worker (task). * * Returns a pointer to the allocated worker on success, ERR_PTR(-ENOMEM) @@ -1074,25 +1068,49 @@ __kthread_create_worker(int cpu, unsigned int flags, * when the caller was killed by a fatal signal. */ struct kthread_worker * -kthread_create_worker(unsigned int flags, const char namefmt[], ...) +kthread_create_worker_on_node(unsigned int flags, int node, const char namefmt[], ...) { struct kthread_worker *worker; va_list args; va_start(args, namefmt); - worker = __kthread_create_worker(-1, flags, namefmt, args); + worker = __kthread_create_worker_on_node(flags, node, namefmt, args); va_end(args); + if (worker) + wake_up_process(worker->task); + + return worker; +} +EXPORT_SYMBOL(kthread_create_worker_on_node); + +static __printf(3, 4) struct kthread_worker * +__kthread_create_worker_on_cpu(int cpu, unsigned int flags, + const char namefmt[], ...) +{ + struct kthread_worker *worker; + va_list args; + + va_start(args, namefmt); + worker = __kthread_create_worker_on_node(flags, cpu_to_node(cpu), + namefmt, args); + va_end(args); + + if (worker) { + kthread_bind(worker->task, cpu); + wake_up_process(worker->task); + } + return worker; } -EXPORT_SYMBOL(kthread_create_worker); /** * kthread_create_worker_on_cpu - create a kthread worker and bind it * to a given CPU and the associated NUMA node. * @cpu: CPU number * @flags: flags modifying the default behavior of the worker - * @namefmt: printf-style name for the kthread worker (task). + * @namefmt: printf-style name for the thread. Format is restricted + * to "name.*%u". Code fills in cpu number. * * Use a valid CPU number if you want to bind the kthread worker * to the given CPU and the associated NUMA node. @@ -1124,16 +1142,9 @@ EXPORT_SYMBOL(kthread_create_worker); */ struct kthread_worker * kthread_create_worker_on_cpu(int cpu, unsigned int flags, - const char namefmt[], ...) + const char namefmt[]) { - struct kthread_worker *worker; - va_list args; - - va_start(args, namefmt); - worker = __kthread_create_worker(cpu, flags, namefmt, args); - va_end(args); - - return worker; + return __kthread_create_worker_on_cpu(cpu, flags, namefmt, cpu); } EXPORT_SYMBOL(kthread_create_worker_on_cpu);