Re: [PATCH v4 3/3] perf record: adapt affinity to machines with #CPUs > 1K

[Alexey Budankov]

On 03.12.2019 14:23, Jiri Olsa wrote:
> On Tue, Dec 03, 2019 at 01:48:05PM +0300, Alexey Budankov wrote:
>>
>>
>> On 03.12.2019 13:12, Jiri Olsa wrote:
>>> On Mon, Dec 02, 2019 at 09:58:48AM +0300, Alexey Budankov wrote:
>>>
>>> SNIP
>>>
>>>>  
>>>> -static void build_node_mask(int node, cpu_set_t *mask)
>>>> +static void build_node_mask(int node, struct mmap_cpu_mask *mask)
>>>>  {
>>>>  	int c, cpu, nr_cpus;
>>>>  	const struct perf_cpu_map *cpu_map = NULL;
>>>> @@ -240,17 +242,23 @@ static void build_node_mask(int node, cpu_set_t *mask)
>>>>  	for (c = 0; c < nr_cpus; c++) {
>>>>  		cpu = cpu_map->map[c]; /* map c index to online cpu index */
>>>>  		if (cpu__get_node(cpu) == node)
>>>> -			CPU_SET(cpu, mask);
>>>> +			set_bit(cpu, mask->bits);
>>>>  	}
>>>>  }
>>>>  
>>>> -static void perf_mmap__setup_affinity_mask(struct mmap *map, struct mmap_params *mp)
>>>> +static int perf_mmap__setup_affinity_mask(struct mmap *map, struct mmap_params *mp)
>>>>  {
>>>> -	CPU_ZERO(&map->affinity_mask);
>>>> +	map->affinity_mask.nbits = cpu__max_cpu();
>>>> +	map->affinity_mask.bits = bitmap_alloc(map->affinity_mask.nbits);
>>>> +	if (!map->affinity_mask.bits)
>>>> +		return -1;
>>>
>>> hum, this one should be also behind (rec->opts.affinity != PERF_AFFINITY_SYS)
>>> condition, right? sry I haven't noticed that before..
>>
>> That has not been so far, but, probably like this:
>>
>> diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c
>> index 7f573f646431..832d2cb94b2c 100644
>> --- a/tools/perf/util/mmap.c
>> +++ b/tools/perf/util/mmap.c
>> @@ -269,7 +269,8 @@ int mmap__mmap(struct mmap *map, struct mmap_params *mp, int fd, int cpu)
>>                 return -1;
>>         }
>>  
>> -       if (perf_mmap__setup_affinity_mask(map, mp)) {
>> +       if (mp->affinity != PERF_AFFINITY_SYS &&
>> +               perf_mmap__setup_affinity_mask(map, mp)) {
>>                 pr_debug2("failed to alloc mmap affinity mask, error %d\n",
>>                           errno);
>>                 return -1;
> 
> yes, that works too

Included into v5.

Thanks,
Alexey