On Thu, 14 Jan 2021, Jonathan Schwender wrote:
> Use max_cpus = sysconf(_SC_NPROCESSORS_CONF) to determine the number of
> the maximum CPU (+1).
> The cpu_for_thread_*() functions check the first max_cpus bits
> in the cpuset / cpumask.
> This fixes failing to set the affinity to CPUs >= num_online_cpus,
> if some intermediate CPU is offline, e.g. on an AMD system
> with nosmt.
>
> Signed-off-by: Jonathan Schwender <schwenderjonathan@xxxxxxxxx>
> ---
> src/cyclictest/cyclictest.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
> index f38c453..b104e4c 100644
> --- a/src/cyclictest/cyclictest.c
> +++ b/src/cyclictest/cyclictest.c
> @@ -1741,7 +1741,8 @@ int main(int argc, char **argv)
> int signum = SIGALRM;
> int mode;
> int cpu;
> - int max_cpus = sysconf(_SC_NPROCESSORS_ONLN);
> + int max_cpus = sysconf(_SC_NPROCESSORS_CONF);
> + int online_cpus = sysconf(_SC_NPROCESSORS_ONLN);
> int i, ret = -1;
> int status;
>
> @@ -1750,8 +1751,10 @@ int main(int argc, char **argv)
> if (check_privs())
> exit(EXIT_FAILURE);
>
> - if (verbose)
> + if (verbose) {
> printf("Max CPUs = %d\n", max_cpus);
> + printf("Online CPUs = %d\n", online_cpus);
> + }
>
> /* Restrict the main pid to the affinity specified by the user */
> if (affinity_mask != NULL) {
> --
> 2.29.2
>
>
Signed-off-by: John Kacur <jkacur@xxxxxxxxxx>
Thanks
