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 <frede...@kernel.org>
---
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 8936790618c6..050aaa016ec8 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -318,7 +318,7 @@ 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)
+__printf(3, 4)
+struct kthread_worker *kthread_create_worker_on_node(unsigned int flags,
+ int node,
+ const char namefmt[], ...);
+
+#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(unsigned int flags, const char namefmt[], ...);
-
-__printf(3, 4) 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 91037533afda..7eb93c248c59 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -1028,12 +1028,11 @@ 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)
@@ -1041,20 +1040,14 @@ __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:
@@ -1065,6 +1058,7 @@ __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)
@@ -1072,25 +1066,49 @@ __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.
@@ -1122,16 +1140,9 @@ 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);
--
2.46.0
