On 4/1/22 09:03, Steven Rostedt wrote: > On Thu, 31 Mar 2022 20:09:25 -0700 > Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: > >> @@ -5908,6 +5910,8 @@ >> trace_buf_size=nn[KMG] >> [FTRACE] will set tracing buffer size on each cpu. >> >> + trace_clock= [FTRACE] See Documentation/trace/ftrace.rst > > trace_clock= [FTRACE] Set the clock used for tracing events > at boot up. > local - Use the per CPU time stamp counter > (converted into nanoseconds). Fast, but > depending on the architecture, may not be > in sync between CPUs. > global - Event time stamps are synchronize across > CPUs. May be slower than the local clock, > but better for some race conditions. > counter - Simple counting of events (1, 2, ..) > note, some counts may be skipped due to the > infrastructure grabbing the clock more than > once per event. > uptime - Use jiffies as the time stamp. > perf - Use the same clock that perf uses. > mono - Use ktime_get_mono_fast_ns() for time stamps. > mono_raw - Use ktime_get_raw_fast_ns() for time > stamps. > boot - Use ktime_get_boot_fast_ns() for time stamps. > Architectures may add more clocks. See > Documentation/trace/ftrace.rst for more details. > Will do. Thanks. > > >> + >> trace_event=[event-list] >> [FTRACE] Set and start specified trace events in order >> to facilitate early boot debugging. The event-list is a -- ~Randy