Re: [PATCH v6 12/21] selftests/resctrl: Check for resctrl mount point only if resctrl FS is supported

[Shuah Khan]

On 3/16/21 8:22 PM, Fenghua Yu wrote:

check_resctrlfs_support() does the following
1. Checks if the platform supports resctrl file system or not by looking
    for resctrl in /proc/filesystems
2. Calls opendir() on default resctrl file system path
    (i.e. /sys/fs/resctrl)
3. Checks if resctrl file system is mounted or not by looking at
    /proc/mounts

Steps 2 and 3 will fail if the platform does not support resctrl file
system. So, there is no need to check for them if step 1 fails.

Fix this by returning immediately if the platform does not support
resctrl file system.

Tested-by: Babu Moger <babu.mo...@amd.com>
Signed-off-by: Fenghua Yu <fenghua...@intel.com>
---
  tools/testing/selftests/resctrl/resctrlfs.c | 3 +++
  1 file changed, 3 insertions(+)

diff --git a/tools/testing/selftests/resctrl/resctrlfs.c 
b/tools/testing/selftests/resctrl/resctrlfs.c
index 6b22a186790a..87195eb78356 100644
--- a/tools/testing/selftests/resctrl/resctrlfs.c
+++ b/tools/testing/selftests/resctrl/resctrlfs.c
@@ -570,6 +570,9 @@ bool check_resctrlfs_support(void)
        ksft_print_msg("%s kernel supports resctrl filesystem\n",
                       ret ? "Pass:" : "Fail:");

This message is a bit confusing. Please change this to read
and send a follow-on patch on top of linux-kselftest next

"Check kernel support for resctrl filesystem"

thanks,
-- Shuah