mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

kthread: save thread function 

It's handy to keep the kthread_fn just as a unique cookie to identify
classes of kthreads.  E.g. if you can verify that a given task is
running your thread_fn, then you may know what sort of type kthread_data
points to.

We'll use this in nfsd to pass some information into the vfs.  Note it
will need kthread_data() exported too.

Original-patch-by: Tejun Heo <tj@kernel.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
J. Bruce Fields 2020-05-06 12:09:34 -04:00
parent 31fb4bf545
commit 52782c92ac
2 changed files with 18 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/kthread.h
View File

@ -57,6 +57,7 @@ bool kthread_should_stop(void);
bool kthread_should_park(void);
bool __kthread_should_park(struct task_struct *k);
bool kthread_freezable_should_stop(bool *was_frozen);
void *kthread_func(struct task_struct *k);
void *kthread_data(struct task_struct *k);
void *kthread_probe_data(struct task_struct *k);
int kthread_park(struct task_struct *k);

17
kernel/kthread.c
View File

@ -46,6 +46,7 @@ struct kthread_create_info
struct kthread {
unsigned long flags;
unsigned int cpu;
int (*threadfn)(void *);
void *data;
struct completion parked;
struct completion exited;
@ -152,6 +153,20 @@ bool kthread_freezable_should_stop(bool *was_frozen)
}
EXPORT_SYMBOL_GPL(kthread_freezable_should_stop);
/**
* kthread_func - return the function specified on kthread creation
* @task: kthread task in question
*
* Returns NULL if the task is not a kthread.
*/
void *kthread_func(struct task_struct *task)
{
if (task->flags & PF_KTHREAD)
return to_kthread(task)->threadfn;
return NULL;
}
EXPORT_SYMBOL_GPL(kthread_func);
/**
* kthread_data - return data value specified on kthread creation
* @task: kthread task in question
@ -164,6 +179,7 @@ void *kthread_data(struct task_struct *task)
{
return to_kthread(task)->data;
}
EXPORT_SYMBOL_GPL(kthread_data);
/**
* kthread_probe_data - speculative version of kthread_data()
@ -244,6 +260,7 @@ static int kthread(void *_create)
do_exit(-ENOMEM);
}
self->threadfn = threadfn;
self->data = data;
init_completion(&self->exited);
init_completion(&self->parked);