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Message-ID: <d2f22b33-6b55-4f02-9a7e-956b5c60d992@kernel.dk>
Date: Sun, 18 Feb 2024 05:55:37 -0700
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Subject: Re: [PATCH v8] io_uring: Statistics of the true utilization of sq
 threads.
Content-Language: en-US
From: Jens Axboe <axboe@kernel.dk>
To: Xiaobing Li <xiaobing.li@samsung.com>
Cc: asml.silence@gmail.com, linux-kernel@vger.kernel.org,
 io-uring@vger.kernel.org, kun.dou@samsung.com, peiwei.li@samsung.com,
 joshi.k@samsung.com, kundan.kumar@samsung.com, wenwen.chen@samsung.com,
 ruyi.zhang@samsung.com
References: <20240206023910.11307-1-xiaobing.li@samsung.com>
 <CGME20240218055523epcas5p390fe990f970cf2b9b1f96edd5d7bc9b5@epcas5p3.samsung.com>
 <20240218055513.38601-1-xiaobing.li@samsung.com>
 <1f7fa75e-f920-47d8-ae4f-cc7595b5e732@kernel.dk>
In-Reply-To: <1f7fa75e-f920-47d8-ae4f-cc7595b5e732@kernel.dk>
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On 2/18/24 5:45 AM, Jens Axboe wrote:
> On 2/17/24 10:55 PM, Xiaobing Li wrote:
>> On 2/6/24 10:39 AM, Xiaobing Li wrote:
>>> io_uring/fdinfo.c | 8 ++++++++
>>> io_uring/sqpoll.c | 8 ++++++++
>>> io_uring/sqpoll.h | 1 +
>>> 3 files changed, 17 insertions(+)
>>>
>>> diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c
>>> index 976e9500f651..18c6f4aa4a48 100644
>>> --- a/io_uring/fdinfo.c
>>> +++ b/io_uring/fdinfo.c
>>> @@ -64,6 +64,7 @@ __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
>>> 	unsigned int sq_shift = 0;
>>> 	unsigned int sq_entries, cq_entries;
>>> 	int sq_pid = -1, sq_cpu = -1;
>>> +	u64 sq_total_time = 0, sq_work_time = 0;
>>> 	bool has_lock;
>>> 	unsigned int i;
>>>
>>> @@ -147,10 +148,17 @@ __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
>>>
>>> 		sq_pid = sq->task_pid;
>>> 		sq_cpu = sq->sq_cpu;
>>> +		struct rusage r;
>>> +
>>> +		getrusage(sq->thread, RUSAGE_SELF, &r);
>>> +		sq_total_time = r.ru_stime.tv_sec * 1000000 + r.ru_stime.tv_usec;
>>> +		sq_work_time = sq->work_time;
>>> 	}
>>>
>>> 	seq_printf(m, "SqThread:\t%d\n", sq_pid);
>>> 	seq_printf(m, "SqThreadCpu:\t%d\n", sq_cpu);
>>> +	seq_printf(m, "SqTotalTime:\t%llu\n", sq_total_time);
>>> +	seq_printf(m, "SqWorkTime:\t%llu\n", sq_work_time);
>>> 	seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
>>> 	for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
>>> 		struct file *f = io_file_from_index(&ctx->file_table, i);
>>> diff --git a/io_uring/sqpoll.c b/io_uring/sqpoll.c
>>> index 65b5dbe3c850..9155fc0b5eee 100644
>>> --- a/io_uring/sqpoll.c
>>> +++ b/io_uring/sqpoll.c
>>> @@ -251,6 +251,9 @@ static int io_sq_thread(void *data)
>>> 		}
>>>
>>> 		cap_entries = !list_is_singular(&sqd->ctx_list);
>>> +		struct rusage start, end;
>>> +
>>> +		getrusage(current, RUSAGE_SELF, &start);
>>> 		list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
>>> 			int ret = __io_sq_thread(ctx, cap_entries);
>>>
>>> @@ -260,6 +263,11 @@ static int io_sq_thread(void *data)
>>> 		if (io_run_task_work())
>>> 			sqt_spin = true;
>>>
>>> +		getrusage(current, RUSAGE_SELF, &end);
>>> +		if (sqt_spin == true)
>>> +			sqd->work_time += (end.ru_stime.tv_sec - start.ru_stime.tv_sec) *
>>> +					1000000 + (end.ru_stime.tv_usec - start.ru_stime.tv_usec);
>>> +
>>> 		if (sqt_spin || !time_after(jiffies, timeout)) {
>>> 			if (sqt_spin)
>>> 				timeout = jiffies + sqd->sq_thread_idle;
>>> diff --git a/io_uring/sqpoll.h b/io_uring/sqpoll.h
>>> index 8df37e8c9149..e99f5423a3c3 100644
>>> --- a/io_uring/sqpoll.h
>>> +++ b/io_uring/sqpoll.h
>>> @@ -16,6 +16,7 @@ struct io_sq_data {
>>> 	pid_t			task_pid;
>>> 	pid_t			task_tgid;
>>>
>>> +	u64					work_time;
>>> 	unsigned long		state;
>>> 	struct completion	exited;
>>> };
>>  
>> Hi, Jens and Pavel
>> This patch has been modified according to your previous opinions.
>> Do you have any other comments?
> 
> I don't have any further complaints on the patch, I think it looks
> pretty straight forward now. I'll get it applied, thanks.

I take that back, I'll reply to the patch...

-- 
Jens Axboe