Re: [PATCH 7/9] io-wq: implement fixed worker logic

From: Hao Xu
Date: Sun May 01 2022 - 03:01:49 EST


On 4/30/22 21:27, Jens Axboe wrote:
On 4/29/22 4:18 AM, Hao Xu wrote:
@@ -1030,6 +1101,7 @@ static bool io_wq_work_match_item(struct io_wq_work *work, void *data)
static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work)
{
struct io_wqe_acct *acct = io_work_get_acct(wqe, work);
+ struct io_wqe_acct *fixed_acct;
struct io_cb_cancel_data match;
unsigned work_flags = work->flags;
bool do_create;
@@ -1044,8 +1116,14 @@ static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work)
return;
}
+ fixed_acct = io_get_acct(wqe, !acct->index, true);
+ if (fixed_acct->fixed_worker_registered && !io_wq_is_hashed(work)) {
+ if (io_wqe_insert_private_work(wqe, work, fixed_acct))
+ return;
+ }
+

As per previous email, I was going to comment back saying "why don't we
just always do hashed work on the non-fixed workers?" - but that's
already what you are doing. Isn't this fine, does anything else need to
get done here in terms of hashed work and fixed workers? If you need
per-iowq serialization, then you don't get a fixed worker.

Hmm, seems we cannot accelerate serialized works with fixed worker. So
Let's make it as it is.