Hi Andrew, thanks for picking this up. The kernel test robot has since told me that it's uhappy about the kerneldoc comment I've added for kthread_stio_put(). So here's an updated version that has the comment fixed, rebased against the latest for-next kernel. https://lore.kernel.org/oe-kbuild-all/202309081653.IMl41FhS-lkp@xxxxxxxxx/ Thanks, Andreas -- 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(). Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx> --- 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 | 17 +++++++++++++++++ kernel/smpboot.c | 3 +-- mm/damon/core.c | 3 +-- net/core/pktgen.c | 3 +-- 13 files changed, 37 insertions(+), 46 deletions(-) diff --git a/drivers/accel/ivpu/ivpu_job.c b/drivers/accel/ivpu/ivpu_job.c index de9e69f70af7..76f468c9f761 100644 --- a/drivers/accel/ivpu/ivpu_job.c +++ b/drivers/accel/ivpu/ivpu_job.c @@ -618,6 +618,5 @@ int ivpu_job_done_thread_init(struct ivpu_device *vdev) 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); } diff --git a/drivers/dma-buf/st-dma-fence-chain.c b/drivers/dma-buf/st-dma-fence-chain.c index c0979c8049b5..9c2a0c082a76 100644 --- a/drivers/dma-buf/st-dma-fence-chain.c +++ b/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); diff --git a/drivers/dma-buf/st-dma-fence.c b/drivers/dma-buf/st-dma-fence.c index fb6e0a6ae2c9..b7c6f7ea9e0c 100644 --- a/drivers/dma-buf/st-dma-fence.c +++ b/drivers/dma-buf/st-dma-fence.c @@ -548,11 +548,9 @@ static int race_signal_callback(void *arg) 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); } } diff --git a/drivers/gpu/drm/i915/gt/selftest_migrate.c b/drivers/gpu/drm/i915/gt/selftest_migrate.c index 3def5ca72dec..0fb07f073baa 100644 --- a/drivers/gpu/drm/i915/gt/selftest_migrate.c +++ b/drivers/gpu/drm/i915/gt/selftest_migrate.c @@ -719,11 +719,9 @@ static int threaded_migrate(struct intel_migrate *migrate, 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); diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index f3f2c07423a6..33c8143619f0 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -672,8 +672,7 @@ int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, 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; } diff --git a/drivers/usb/usbip/usbip_common.h b/drivers/usb/usbip/usbip_common.h index d8cbd2dfc2c2..282efca64a01 100644 --- a/drivers/usb/usbip/usbip_common.h +++ b/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); diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index 33ca04733e93..ecf789b7168c 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -1126,8 +1126,7 @@ static int init_threads(struct gfs2_sbd *sdp) 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 @@ static int init_threads(struct gfs2_sbd *sdp) 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; } } diff --git a/include/linux/kthread.h b/include/linux/kthread.h index 2c30ade43bc8..b11f53c1ba2e 100644 --- a/include/linux/kthread.h +++ b/include/linux/kthread.h @@ -86,6 +86,7 @@ void free_kthread_struct(struct task_struct *k); 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); diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index d309ba84e08a..1782f90cd8c6 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1852,15 +1852,13 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) 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(struct irq_desc *desc, void *dev_id) * 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 */ diff --git a/kernel/kthread.c b/kernel/kthread.c index c46128ec0c0a..c4453181daf9 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -715,6 +715,23 @@ int kthread_stop(struct task_struct *k) } EXPORT_SYMBOL(kthread_stop); +/** + * kthread_stop_put - stop a thread and put its task struct + * + * Stops a thread created by kthread_create() and put its task_struct. + * Only use when holding an extra task struct reference obtained by + * calling get_task_struct(). + */ +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; diff --git a/kernel/smpboot.c b/kernel/smpboot.c index f47d8f375946..1992b62e980b 100644 --- a/kernel/smpboot.c +++ b/kernel/smpboot.c @@ -272,8 +272,7 @@ static void smpboot_destroy_threads(struct smp_hotplug_thread *ht) 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; } } diff --git a/mm/damon/core.c b/mm/damon/core.c index bcd2bd9d6c10..2f54f153d7f5 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -699,8 +699,7 @@ static int __damon_stop(struct damon_ctx *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); diff --git a/net/core/pktgen.c b/net/core/pktgen.c index f56b8d697014..826250a0f5b1 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -3982,8 +3982,7 @@ static void __net_exit pg_net_exit(struct net *net) 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); } -- 2.40.1
