This patch provides a test utility which helps capture GuC firmware logs and
then dump them to file.
The logs are pulled from a debugfs file '/sys/kernel/debug/dri/guc_log' and
by default stored into a file 'guc_log_dump.dat'. The name, including the
location, of the output file can be changed through a command line argument.
The utility goes into an infinite loop where it waits for the arrival of new
logs and as soon as new set of logs are produced it captures them in its local
buffer which is then flushed out to the file on disk.
Any time when logging needs to be ended, User can stop this utility (CTRL+C).
Before entering into a loop, it first discards whatever logs are present in
the debugfs file.
This way User can first launch this utility and then start a workload/activity
for which GuC firmware logs are to be actually captured and keep running the
utility for as long as its needed, like once the workload is over this utility
can be forcefully stopped.
If the logging wasn't enabled on GuC side by the Driver at boot time, utility
will first enable the logging and later on when it is stopped (CTRL+C) it will
also pause the logging on GuC side.
v2:
- Use combination of alarm system call & SIGALRM signal to run the utility
for required duration. (Tvrtko)
- Fix inconsistencies, do minor cleanup and refactoring. (Tvrtko)
v3:
- Fix discrepancy for the output file command line option and update the
Usage/help string.
v4:
- Update the exit condition for flusher thread, now will exit only after
the capture loop is over and not when the flag to stop logging is set.
This handles a corner case, due to which the dump of last captured buffer
was getting missed.
- Add a newline character at the end of assert messages.
- Avoid the assert for the case, which occurs very rarely, when there are no
bytes read from the relay file.
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> (v3)
2 files changed