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Message-ID: <b90f96e9-3209-2285-fd1d-9a7660cf5e1a@gmail.com>
Date:   Sun, 1 May 2022 15:00:04 +0800
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Subject: Re: [PATCH 7/9] io-wq: implement fixed worker logic
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To:     Jens Axboe <axboe@kernel.dk>, io-uring@vger.kernel.org
Cc:     Pavel Begunkov <asml.silence@gmail.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220429101858.90282-1-haoxu.linux@gmail.com>
 <20220429101858.90282-8-haoxu.linux@gmail.com>
 <015f58ed-09c1-cd27-064a-b6c0cc5580d2@kernel.dk>
From:   Hao Xu <haoxu.linux@gmail.com>
In-Reply-To: <015f58ed-09c1-cd27-064a-b6c0cc5580d2@kernel.dk>
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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.
>