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Subject: Re: [PATCH v9 11/15] perf stat: implement control commands handling
To:     Jiri Olsa <jolsa@redhat.com>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Andi Kleen <ak@linux.intel.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
References: <a4d5db4a-f25c-38dc-1c41-321a886cb122@linux.intel.com>
 <21669f5a-6220-df0a-09f1-b73b32487f23@linux.intel.com>
 <20200706123743.GE3401866@krava>
From:   Alexey Budankov <alexey.budankov@linux.intel.com>
Organization: Intel Corp.
Message-ID: <b43873d9-2b29-23ed-2187-9e2eb31ee587@linux.intel.com>
Date:   Mon, 6 Jul 2020 16:10:14 +0300
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On 06.07.2020 15:37, Jiri Olsa wrote:
> On Fri, Jul 03, 2020 at 10:47:22AM +0300, Alexey Budankov wrote:
> 
> SNIP
> 
>>  
>>  	while (1) {
>>  		if (forks)
>> @@ -574,11 +610,22 @@ static int dispatch_events(bool forks, int timeout, int interval, int *times, st
>>  		if (done || stop || child_exited)
>>  			break;
>>  
>> -		nanosleep(ts, NULL);
>> -		if (timeout)
>> -			stop = true;
>> -		else
>> -			stop = handle_interval(interval, times);
>> +		clock_gettime(CLOCK_MONOTONIC, &time_start);
>> +		if (!(evlist__poll(evsel_list, time_to_sleep) > 0)) { /* poll timeout or EINTR */
>> +			if (timeout)
>> +				stop = true;
>> +			else
>> +				stop = handle_interval(interval, times);
>> +			time_to_sleep = sleep_time;
>> +		} else { /* fd revent */
>> +			stop = process_evlist(evsel_list, interval, times);
>> +			clock_gettime(CLOCK_MONOTONIC, &time_stop);
>> +			diff_timespec(&time_diff, &time_stop, &time_start);
>> +			time_to_sleep -= time_diff.tv_sec * MSEC_PER_SEC +
>> +					 time_diff.tv_nsec / NSEC_PER_MSEC;
>> +			if (time_to_sleep < 0)
>> +				time_to_sleep = 0;
> 
> could this computation go to a separate function? something like:
> 
> time_to_sleep = compute_tts(time_start, time_stop);

Accepted. In v10.

Alexey