io-wq: add io_wq_cancel_pid() to cancel based on a specific pid

Add a helper that allows the caller to cancel work based on what mm
it belongs to. This allows io_uring to cancel work from a given
task or thread when it exits.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2020-02-08 19:16:39 -07:00
parent 00bcda13dc
commit 36282881a7
2 changed files with 31 additions and 0 deletions

View File

@ -1029,6 +1029,35 @@ enum io_wq_cancel io_wq_cancel_work(struct io_wq *wq, struct io_wq_work *cwork)
return ret;
}
static bool io_wq_pid_match(struct io_wq_work *work, void *data)
{
pid_t pid = (pid_t) (unsigned long) data;
if (work)
return work->task_pid == pid;
return false;
}
enum io_wq_cancel io_wq_cancel_pid(struct io_wq *wq, pid_t pid)
{
struct work_match match = {
.fn = io_wq_pid_match,
.data = (void *) (unsigned long) pid
};
enum io_wq_cancel ret = IO_WQ_CANCEL_NOTFOUND;
int node;
for_each_node(node) {
struct io_wqe *wqe = wq->wqes[node];
ret = io_wqe_cancel_work(wqe, &match);
if (ret != IO_WQ_CANCEL_NOTFOUND)
break;
}
return ret;
}
struct io_wq_flush_data {
struct io_wq_work work;
struct completion done;

View File

@ -76,6 +76,7 @@ struct io_wq_work {
const struct cred *creds;
struct fs_struct *fs;
unsigned flags;
pid_t task_pid;
};
#define INIT_IO_WORK(work, _func) \
@ -109,6 +110,7 @@ void io_wq_flush(struct io_wq *wq);
void io_wq_cancel_all(struct io_wq *wq);
enum io_wq_cancel io_wq_cancel_work(struct io_wq *wq, struct io_wq_work *cwork);
enum io_wq_cancel io_wq_cancel_pid(struct io_wq *wq, pid_t pid);
typedef bool (work_cancel_fn)(struct io_wq_work *, void *);