Re: [PATCH 8/8] perf bench futex: Fix wording in futex bench messages

[Namhyung Kim]

On Sat, Sep 26, 2026 at 08:04:07PM +0100, Michal Pluta wrote:
> When the kernel is using a different number of hash buckets than
> requested with -b, the message printed is ungrammatical, and it ends
> with a stale errno even though nothing failed:
> 
>   Requested number of hash buckets does not currently used.
>   Requested: 3 in usage: 64
>   perf: prctl(PR_FUTEX_HASH): No such file or directory
> 
> Fix the wording and use errx(), so that no errno text is printed:
> 
>   Requested number of buckets differs from the number in use.
>   Requested: 3, in use: 64
>   perf: prctl(PR_FUTEX_HASH)

Maybe better split the errx() change as it seems there are some other
places need the same change.

Thanks,
Namhyung

> 
> Also fix "Wokeup" in the 'futex wake' output, which should be "Woke up".
> 
> Fixes: 60035a3981a7 ("tools/perf: Allow to select the number of hash buckets")
> Assisted-by: LLM
> Signed-off-by: Michal Pluta <michalpl2003@xxxxxxxxx>
> ---
>  tools/perf/bench/futex-wake.c | 4 ++--
>  tools/perf/bench/futex.c      | 6 +++---
>  2 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/perf/bench/futex-wake.c b/tools/perf/bench/futex-wake.c
> index 7674622639ca..2cbf31e121d5 100644
> --- a/tools/perf/bench/futex-wake.c
> +++ b/tools/perf/bench/futex-wake.c
> @@ -89,7 +89,7 @@ static void print_summary(void)
>  	double waketime_stddev = stddev_stats(&waketime_stats);
>  	unsigned int wakeup_avg = avg_stats(&wakeup_stats);
>  
> -	printf("Wokeup %d of %d threads in %.4f ms (+-%.2f%%)\n",
> +	printf("Woke up %d of %d threads in %.4f ms (+-%.2f%%)\n",
>  	       wakeup_avg,
>  	       params.nthreads,
>  	       waketime_avg / USEC_PER_MSEC,
> @@ -223,7 +223,7 @@ int bench_futex_wake(int argc, const char **argv)
>  		update_stats(&waketime_stats, runtime_us);
>  
>  		if (!params.silent) {
> -			printf("[Run %d]: Wokeup %d of %d threads in %.4f ms\n",
> +			printf("[Run %d]: Woke up %d of %d threads in %.4f ms\n",
>  			       j + 1, nwoken, params.nthreads,
>  			       runtime_us / (double)USEC_PER_MSEC);
>  		}
> diff --git a/tools/perf/bench/futex.c b/tools/perf/bench/futex.c
> index 5757d47f8f7c..be0cbc03682c 100644
> --- a/tools/perf/bench/futex.c
> +++ b/tools/perf/bench/futex.c
> @@ -43,9 +43,9 @@ void futex_print_nbuckets(struct bench_futex_parameters *params)
>  				printf("Can't query number of buckets: %m\n");
>  				err(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
>  			}
> -			printf("Requested number of hash buckets does not currently used.\n");
> -			printf("Requested: %d in usage: %d\n", params->nbuckets, ret);
> -			err(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
> +			printf("Requested number of buckets differs from the number in use.\n");
> +			printf("Requested: %d, in use: %d\n", params->nbuckets, ret);
> +			errx(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
>  		}
>  		if (params->nbuckets == 0)
>  			ret = asprintf(&futex_hash_mode, "Futex hashing: global hash");
> -- 
> 2.43.0
>