The patch titled
Subject: kthread: add kthread_stop_put
has been added to the -mm mm-nonmm-unstable branch. Its filename is
kthread-add-kthread_stop_put.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kthread-add-kthread_stop_put.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Subject: kthread: add kthread_stop_put
Date: Fri, 8 Sep 2023 01:40:48 +0200
Add a kthread_stop_put() helper that stops a thread and puts its task
struct. Use it to replace the various instances of kthread_stop()
followed by put_task_struct().
Remove the kthread_stop_put() macro in usbip that is similar but doesn't
return the result of kthread_stop().
Link: https://lkml.kernel.org/r/20230907234048.2499820-1-agruenba@xxxxxxxxxx
Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/accel/ivpu/ivpu_job.c | 3 --
drivers/dma-buf/st-dma-fence-chain.c | 12 +++------
drivers/dma-buf/st-dma-fence.c | 4 ---
drivers/gpu/drm/i915/gt/selftest_migrate.c | 4 ---
drivers/net/xen-netback/interface.c | 3 --
drivers/usb/usbip/usbip_common.h | 6 ----
fs/gfs2/ops_fstype.c | 9 ++-----
include/linux/kthread.h | 1
kernel/irq/manage.c | 15 +++--------
kernel/kthread.c | 24 +++++++++++++++++++
kernel/smpboot.c | 3 --
mm/damon/core.c | 3 --
net/core/pktgen.c | 3 --
13 files changed, 44 insertions(+), 46 deletions(-)
--- a/drivers/accel/ivpu/ivpu_job.c~kthread-add-kthread_stop_put
+++ a/drivers/accel/ivpu/ivpu_job.c
@@ -618,6 +618,5 @@ int ivpu_job_done_thread_init(struct ivp
void ivpu_job_done_thread_fini(struct ivpu_device *vdev)
{
- kthread_stop(vdev->job_done_thread);
- put_task_struct(vdev->job_done_thread);
+ kthread_stop_put(vdev->job_done_thread);
}
--- a/drivers/dma-buf/st-dma-fence.c~kthread-add-kthread_stop_put
+++ a/drivers/dma-buf/st-dma-fence.c
@@ -548,11 +548,9 @@ static int race_signal_callback(void *ar
for (i = 0; i < ARRAY_SIZE(t); i++) {
int err;
- err = kthread_stop(t[i].task);
+ err = kthread_stop_put(t[i].task);
if (err && !ret)
ret = err;
-
- put_task_struct(t[i].task);
}
}
--- a/drivers/dma-buf/st-dma-fence-chain.c~kthread-add-kthread_stop_put
+++ a/drivers/dma-buf/st-dma-fence-chain.c
@@ -476,10 +476,9 @@ static int find_race(void *arg)
for (i = 0; i < ncpus; i++) {
int ret;
- ret = kthread_stop(threads[i]);
+ ret = kthread_stop_put(threads[i]);
if (ret && !err)
err = ret;
- put_task_struct(threads[i]);
}
kfree(threads);
@@ -591,8 +590,7 @@ static int wait_forward(void *arg)
for (i = 0; i < fc.chain_length; i++)
dma_fence_signal(fc.fences[i]);
- err = kthread_stop(tsk);
- put_task_struct(tsk);
+ err = kthread_stop_put(tsk);
err:
fence_chains_fini(&fc);
@@ -621,8 +619,7 @@ static int wait_backward(void *arg)
for (i = fc.chain_length; i--; )
dma_fence_signal(fc.fences[i]);
- err = kthread_stop(tsk);
- put_task_struct(tsk);
+ err = kthread_stop_put(tsk);
err:
fence_chains_fini(&fc);
@@ -669,8 +666,7 @@ static int wait_random(void *arg)
for (i = 0; i < fc.chain_length; i++)
dma_fence_signal(fc.fences[i]);
- err = kthread_stop(tsk);
- put_task_struct(tsk);
+ err = kthread_stop_put(tsk);
err:
fence_chains_fini(&fc);
--- a/drivers/gpu/drm/i915/gt/selftest_migrate.c~kthread-add-kthread_stop_put
+++ a/drivers/gpu/drm/i915/gt/selftest_migrate.c
@@ -719,11 +719,9 @@ static int threaded_migrate(struct intel
if (IS_ERR_OR_NULL(tsk))
continue;
- status = kthread_stop(tsk);
+ status = kthread_stop_put(tsk);
if (status && !err)
err = status;
-
- put_task_struct(tsk);
}
kfree(thread);
--- a/drivers/net/xen-netback/interface.c~kthread-add-kthread_stop_put
+++ a/drivers/net/xen-netback/interface.c
@@ -672,8 +672,7 @@ err:
static void xenvif_disconnect_queue(struct xenvif_queue *queue)
{
if (queue->task) {
- kthread_stop(queue->task);
- put_task_struct(queue->task);
+ kthread_stop_put(queue->task);
queue->task = NULL;
}
--- a/drivers/usb/usbip/usbip_common.h~kthread-add-kthread_stop_put
+++ a/drivers/usb/usbip/usbip_common.h
@@ -298,12 +298,6 @@ struct usbip_device {
__k; \
})
-#define kthread_stop_put(k) \
- do { \
- kthread_stop(k); \
- put_task_struct(k); \
- } while (0)
-
/* usbip_common.c */
void usbip_dump_urb(struct urb *purb);
void usbip_dump_header(struct usbip_header *pdu);
--- a/fs/gfs2/ops_fstype.c~kthread-add-kthread_stop_put
+++ a/fs/gfs2/ops_fstype.c
@@ -1126,8 +1126,7 @@ static int init_threads(struct gfs2_sbd
return 0;
fail:
- kthread_stop(sdp->sd_logd_process);
- put_task_struct(sdp->sd_logd_process);
+ kthread_stop_put(sdp->sd_logd_process);
sdp->sd_logd_process = NULL;
return error;
}
@@ -1135,13 +1134,11 @@ fail:
void gfs2_destroy_threads(struct gfs2_sbd *sdp)
{
if (sdp->sd_logd_process) {
- kthread_stop(sdp->sd_logd_process);
- put_task_struct(sdp->sd_logd_process);
+ kthread_stop_put(sdp->sd_logd_process);
sdp->sd_logd_process = NULL;
}
if (sdp->sd_quotad_process) {
- kthread_stop(sdp->sd_quotad_process);
- put_task_struct(sdp->sd_quotad_process);
+ kthread_stop_put(sdp->sd_quotad_process);
sdp->sd_quotad_process = NULL;
}
}
--- a/include/linux/kthread.h~kthread-add-kthread_stop_put
+++ a/include/linux/kthread.h
@@ -86,6 +86,7 @@ void free_kthread_struct(struct task_str
void kthread_bind(struct task_struct *k, unsigned int cpu);
void kthread_bind_mask(struct task_struct *k, const struct cpumask *mask);
int kthread_stop(struct task_struct *k);
+int kthread_stop_put(struct task_struct *k);
bool kthread_should_stop(void);
bool kthread_should_park(void);
bool kthread_should_stop_or_park(void);
--- a/kernel/irq/manage.c~kthread-add-kthread_stop_put
+++ a/kernel/irq/manage.c
@@ -1852,15 +1852,13 @@ out_thread:
struct task_struct *t = new->thread;
new->thread = NULL;
- kthread_stop(t);
- put_task_struct(t);
+ kthread_stop_put(t);
}
if (new->secondary && new->secondary->thread) {
struct task_struct *t = new->secondary->thread;
new->secondary->thread = NULL;
- kthread_stop(t);
- put_task_struct(t);
+ kthread_stop_put(t);
}
out_mput:
module_put(desc->owner);
@@ -1971,12 +1969,9 @@ static struct irqaction *__free_irq(stru
* the same bit to a newly requested action.
*/
if (action->thread) {
- kthread_stop(action->thread);
- put_task_struct(action->thread);
- if (action->secondary && action->secondary->thread) {
- kthread_stop(action->secondary->thread);
- put_task_struct(action->secondary->thread);
- }
+ kthread_stop_put(action->thread);
+ if (action->secondary && action->secondary->thread)
+ kthread_stop_put(action->secondary->thread);
}
/* Last action releases resources */
--- a/kernel/kthread.c~kthread-add-kthread_stop_put
+++ a/kernel/kthread.c
@@ -715,6 +715,30 @@ int kthread_stop(struct task_struct *k)
}
EXPORT_SYMBOL(kthread_stop);
+/**
+ * kthread_stop_put - stop a thread and put its task struct
+ *
+ * Stops a kthread and put its task_struct. This is meant for callers
+ * that are holding an extra reference on the task struct, for example:
+ *
+ * t = kthread_create(...);
+ * if (!IS_ERR(t)) {
+ * get_task_struct(t);
+ * wake_up_process(t);
+ * }
+ *
+ * Returns the result of kthread_stop().
+ */
+int kthread_stop_put(struct task_struct *k)
+{
+ int ret;
+
+ ret = kthread_stop(k);
+ put_task_struct(k);
+ return ret;
+}
+EXPORT_SYMBOL(kthread_stop_put);
+
int kthreadd(void *unused)
{
struct task_struct *tsk = current;
--- a/kernel/smpboot.c~kthread-add-kthread_stop_put
+++ a/kernel/smpboot.c
@@ -272,8 +272,7 @@ static void smpboot_destroy_threads(stru
struct task_struct *tsk = *per_cpu_ptr(ht->store, cpu);
if (tsk) {
- kthread_stop(tsk);
- put_task_struct(tsk);
+ kthread_stop_put(tsk);
*per_cpu_ptr(ht->store, cpu) = NULL;
}
}
--- a/mm/damon/core.c~kthread-add-kthread_stop_put
+++ a/mm/damon/core.c
@@ -699,8 +699,7 @@ static int __damon_stop(struct damon_ctx
if (tsk) {
get_task_struct(tsk);
mutex_unlock(&ctx->kdamond_lock);
- kthread_stop(tsk);
- put_task_struct(tsk);
+ kthread_stop_put(tsk);
return 0;
}
mutex_unlock(&ctx->kdamond_lock);
--- a/net/core/pktgen.c~kthread-add-kthread_stop_put
+++ a/net/core/pktgen.c
@@ -3982,8 +3982,7 @@ static void __net_exit pg_net_exit(struc
list_for_each_safe(q, n, &list) {
t = list_entry(q, struct pktgen_thread, th_list);
list_del(&t->th_list);
- kthread_stop(t->tsk);
- put_task_struct(t->tsk);
+ kthread_stop_put(t->tsk);
kfree(t);
}
_
Patches currently in -mm which might be from agruenba@xxxxxxxxxx are
kthread-add-kthread_stop_put.patch
