Re: [PATCH v10] io_uring: Statistics of the true utilization of sq threads.

[Xiaobing Li <xiaobing.li@samsung.com>]

On 2/28/24 16:51, Xiaobing Li wrote:
>diff --git a/io_uring/fdinfo.c b/io_uring/fdinfo.c
>index 976e9500f651..42b449e53535 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 +148,15 @@ __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
> 
> 		sq_pid = sq->task_pid;
> 		sq_cpu = sq->sq_cpu;
>+		getrusage(sq->thread, RUSAGE_SELF, &sq_usage);
>+		sq_total_time = sq_usage.ru_stime.tv_sec * 1000000 + sq_usage.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 82672eaaee81..363052b4ea76 100644
>--- a/io_uring/sqpoll.c
>+++ b/io_uring/sqpoll.c
>@@ -253,11 +253,23 @@ static bool io_sq_tw_pending(struct llist_node *retry_list)
> 	return retry_list || !llist_empty(&tctx->task_list);
> }
> 
>+static void io_sq_update_worktime(struct io_sq_data *sqd, struct rusage *start)
>+{
>+	struct rusage end;
>+
>+	getrusage(current, RUSAGE_SELF, &end);
>+	end.ru_stime.tv_sec -= start->ru_stime.tv_sec;
>+	end.ru_stime.tv_usec -= start->ru_stime.tv_usec;
>+
>+	sqd->work_time += end.ru_stime.tv_usec + end.ru_stime.tv_sec * 1000000;
>+}
>+
> static int io_sq_thread(void *data)
> {
> 	struct llist_node *retry_list = NULL;
> 	struct io_sq_data *sqd = data;
> 	struct io_ring_ctx *ctx;
>+	struct rusage start;
> 	unsigned long timeout = 0;
> 	char buf[TASK_COMM_LEN];
> 	DEFINE_WAIT(wait);
>@@ -286,6 +298,7 @@ static int io_sq_thread(void *data)
> 		}
> 
> 		cap_entries = !list_is_singular(&sqd->ctx_list);
>+		getrusage(current, RUSAGE_SELF, &start);
> 		list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
> 			int ret = __io_sq_thread(ctx, cap_entries);
> 
>@@ -296,8 +309,10 @@ static int io_sq_thread(void *data)
> 			sqt_spin = true;
> 
> 		if (sqt_spin || !time_after(jiffies, timeout)) {
>-			if (sqt_spin)
>+			if (sqt_spin) {
>+				io_sq_update_worktime(sqd, &start);
> 				timeout = jiffies + sqd->sq_thread_idle;
>+			}
> 			if (unlikely(need_resched())) {
> 				mutex_unlock(&sqd->lock);
> 				cond_resched();
>diff --git a/io_uring/sqpoll.h b/io_uring/sqpoll.h
>index 8df37e8c9149..4171666b1cf4 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;
> };
 
Sorry, please ignore this patch, I will resend a v10.

--
Xiaobing Li