[PATCH v2 0/2] selftests/resctrl: Bug fix and optimizations

[Wieczor-Retman, Maciej]

Write_schemata() uses fprintf() to write a bitmask into a schemata file
inside resctrl FS. It checks fprintf() return value but it doesn't check
fclose() return value. Error codes from fprintf() such as write errors,
are flushed back to the user only after fclose() is executed which means
any invalid bitmask can be written into the schemata file.

Rewrite write_schemata() to use syscalls instead of stdio functions to
interact with the schemata file.

Change sprintf() to snprintf() in write_schemata().

In case of write() returning an error pass the string acquired with
strerror() to the "reason" buffer.

Extend "reason" buffer by a factor of two so it can hold longer error
messages.

The resctrlfs.c file defines functions that interact with the resctrl FS
while resctrl_val.c file defines functions that perform measurements on
the cache. Run_benchmark() fits logically into the second file before
resctrl_val() function that uses it.

Move run_benchmark() from resctrlfs.c to resctrl_val.c just before
resctrl_val() function definition.

Series is based on kselftest next branch.

Changelog v2:
- Change sprintf() to snprintf() in write_schemata().
- Redo write_schemata() with syscalls instead of stdio functions.
- Fix typos and missing dots in patch messages.
- Branch printf attribute patch to a separate series.

[v1] https://lore.kernel.org/all/cover.1692880423.git.maciej.wieczor-retman@xxxxxxxxx/

Wieczor-Retman, Maciej (2):
  selftests/resctrl: Fix schemata write error check
  selftests/resctrl: Move run_benchmark() to a more fitting file

 tools/testing/selftests/resctrl/resctrl_val.c | 50 ++++++++++++
 tools/testing/selftests/resctrl/resctrlfs.c   | 76 ++++---------------
 2 files changed, 63 insertions(+), 63 deletions(-)


base-commit: 13eb52f6293dbda02890698d92f3d9913d8d5aeb
-- 
2.42.0