Re: [PATCH v5 04/19] selftests/resctrl: Close perf value read fd on errors

[Reinette Chatre <reinette.chatre@intel.com>]

Hi Ilpo,

On 7/17/2023 6:14 AM, Ilpo Järvinen wrote:
> Perf event fd (fd_lm) is not closed when run_fill_buf() returns error.
> 
> Close fd_lm only in cat_val() to make it easier to track it is always
> closed.
> 
> Fixes: 790bf585b0ee ("selftests/resctrl: Add Cache Allocation Technology (CAT) selftest")
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> ---
>  tools/testing/selftests/resctrl/cache.c | 18 +++++++++++-------
>  1 file changed, 11 insertions(+), 7 deletions(-)
> 
> diff --git a/tools/testing/selftests/resctrl/cache.c b/tools/testing/selftests/resctrl/cache.c
> index 8a4fe8693be6..289b619116fe 100644
> --- a/tools/testing/selftests/resctrl/cache.c
> +++ b/tools/testing/selftests/resctrl/cache.c
> @@ -87,21 +87,19 @@ static int reset_enable_llc_perf(pid_t pid, int cpu_no)
>  static int get_llc_perf(unsigned long *llc_perf_miss)
>  {
>  	__u64 total_misses;
> +	int ret;
>  
>  	/* Stop counters after one span to get miss rate */
>  
>  	ioctl(fd_lm, PERF_EVENT_IOC_DISABLE, 0);
>  
> -	if (read(fd_lm, &rf_cqm, sizeof(struct read_format)) == -1) {
> +	ret = read(fd_lm, &rf_cqm, sizeof(struct read_format));
> +	if (ret == -1) {
>  		perror("Could not get llc misses through perf");
> -
>  		return -1;
>  	}

Above changes seem to be remnant of previous version that are
not needed.

Reinette