Re: [PATCH v6 2/2] selftests/resctrl: Discover SNC kernel support and adjust messages

Hi Maciej,

On 12/2/24 3:08 AM, Maciej Wieczor-Retman wrote:

diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index 50561993d37c..d0a5c0f78397 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -949,3 +949,35 @@ unsigned int count_bits(unsigned long n) return count; }

+/**

• • snc_kernel_support - Check for existence of mon_sub_L3_00 file that indicates
• • SNC resctrl support on the kernel side.
• • Return: 0 if not supported, 1 if SNC is disabled or SNC discovery is
• • unreliable or SNC is both enabled and supported.
• */

+int snc_kernel_support(void) +{

• char node_path[PATH_MAX];
• struct stat statbuf;
• int ret;
• ret = snc_nodes_per_l3_cache();
• /*

• * If SNC is disabled then its kernel support isn't important. If SNC
  

• * got disabled because the discovery process was unreliable the
  

• * snc_unreliable variable was set. It can be used to verify the SNC
  

• * discovery reliability elsewhere in the selftest.
  

• */
  

• if (ret == 1)

• return ret;
  

• snprintf(node_path, sizeof(node_path), "%s/%s/%s", RESCTRL_PATH, "mon_data",

•  "mon_L3_00/mon_sub_L3_00");
  

The patch looks good. I am curious why the string constants are split in two and not, for example, a single constant of "mon_data/mon_L3_00/mon_sub_L3_00"?

• if (!stat(node_path, &statbuf))

• return 1;
  

• return 0;

+}

Reinette