Re: [PATCH rt-tests 2/2] oslat: Use cpuset size as upper bound

[John Kacur <jkacur@redhat.com>]

On Wed, 10 Feb 2021, Daniel Wagner wrote:

> To assign the threads to the correct CPU we need to use the cpuset
> size as upper bound for the loop and not the number of threads.
> 
> Fixes: 85b0763dacd9 ("oslat: Use parse_cpumask() from rt-numa.h")
> Reported-by: Peter Xu <peterx@redhat.com>
> Signed-off-by: Daniel Wagner <dwagner@suse.de>
> ---
>  src/oslat/oslat.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/src/oslat/oslat.c b/src/oslat/oslat.c
> index d3f659b218b0..62b82098419a 100644
> --- a/src/oslat/oslat.c
> +++ b/src/oslat/oslat.c
> @@ -742,9 +742,12 @@ int main(int argc, char *argv[])
>  	n_cores = numa_bitmask_weight(cpu_set);
>  
>  	TEST(threads = calloc(1, n_cores * sizeof(threads[0])));
> -	for (i = 0; i < n_cores; ++i)
> -		if (numa_bitmask_isbitset(cpu_set, i) && move_to_core(i) == 0)
> +	for (i = 0; n_cores && i < cpu_set->size; i++) {
> +		if (numa_bitmask_isbitset(cpu_set, i) && move_to_core(i) == 0) {
>  			threads[g.n_threads_total++].core_i = i;
> +			n_cores--;
> +		}
> +	}
>  
>  	if (numa_bitmask_isbitset(cpu_set, 0) && g.rtprio)
>  		printf("WARNING: Running SCHED_FIFO workload on CPU 0 may hang the thread\n");
> -- 
> 2.30.0
> 
> 

This looks okay, but we are waiting for Pradipta's testing to confirm 
before I push it.

Thanks

John