The "trace-cmd reset" command is supposed to set the ftrace state to default. However, some ftrace configurations are not reseted: synthetic events and error_log file. The command is extended to clean these. Two new tracefs APIs were also implemented, to check if given ftrace file / directory exists: bool tracefs_file_exist(struct tracefs_instance *instance, char *name); bool tracefs_dir_exist(struct tracefs_instance *instance, char *name); [ v5 changes: Removed accepted patches from the set Address Steven's comments v4 chanegs: Implemented new tracefs APIs to check if given ftrace file / directory exists. Use the new APIs to check if synthetic_events and error_log files exist, before accessing them. v3 changes: Remove the warning in case there are no configured synthetic events. v2 changes: Removed these patches from the "SQL-like syntax for ftrace histograms configuration" patch set, as they are not directly related to it. ] Tzvetomir Stoyanov (VMware) (3): trace-cmd: Add new tracefs APIs for checking if a ftrace file / directory exists trace-cmd: Unit tests for new libtracefs APIs trace-cmd: Clear error log on reset subcommand include/tracefs/tracefs.h | 3 +++ lib/tracefs/tracefs-instance.c | 46 +++++++++++++++++++++++++++++++++- tracecmd/trace-record.c | 23 +++++++++++++++++ utest/tracefs-utest.c | 16 ++++++++++++ 4 files changed, 87 insertions(+), 1 deletion(-) -- 2.25.1