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At fork time, this flag is set for kernel threads. This is in preparation for allowing kernel threads to signal that they will run deferred task_work. No functional changes in this patch. Signed-off-by: Jens Axboe --- fs/file_table.c | 2 +- include/linux/sched.h | 2 +- kernel/fork.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/file_table.c b/fs/file_table.c index 4f03beed4737..d7c6685afbcb 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -477,7 +477,7 @@ void fput(struct file *file) file_free(file); return; } - if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) { + if (likely(!in_interrupt() && !(task->flags & PF_NO_TASKWORK))) { init_task_work(&file->f_task_work, ____fput); if (!task_work_add(task, &file->f_task_work, TWA_RESUME)) return; diff --git a/include/linux/sched.h b/include/linux/sched.h index 61591ac6eab6..1393d557f05e 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1635,7 +1635,7 @@ extern struct pid *cad_pid; #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */ #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ -#define PF__HOLE__00010000 0x00010000 +#define PF_NO_TASKWORK 0x00010000 /* task doesn't run task_work */ #define PF_KSWAPD 0x00020000 /* I am kswapd */ #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */ #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */ diff --git a/kernel/fork.c b/kernel/fork.c index 99076dbe27d8..156bf8778d18 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2222,7 +2222,7 @@ __latent_entropy struct task_struct *copy_process( goto fork_out; p->flags &= ~PF_KTHREAD; if (args->kthread) - p->flags |= PF_KTHREAD; + p->flags |= PF_KTHREAD | PF_NO_TASKWORK; if (args->user_worker) { /* * Mark us a user worker, and block any signal that isn't