Documentation/trace/ftrace.rst

858   #                            || / _--=> preempt-depth
899   # latency: 259 us, #4/4, CPU#2 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
911   #                ||| / _--=> preempt-depth
976   preempt-depth: The level of preempt_disabled
1191 	Shows the interrupt, preempt count, need resched data.
1365   # latency: 16 us, #4/4, CPU#0 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
1377   #                ||| / _--=> preempt-depth
1416   # latency: 71 us, #168/168, CPU#3 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
1428   #                ||| / _--=> preempt-depth
1505   #                                     || / _--=> preempt-depth
1544 before it can preempt a lower priority task.
1564   # latency: 46 us, #4/4, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
1576   #                ||| / _--=> preempt-depth
1593 the preempt off section and leaving it (the 'd'). We do not know if
1602   # latency: 83 us, #241/241, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
1614   #                ||| / _--=> preempt-depth
1716   # latency: 100 us, #4/4, CPU#3 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
1728   #                ||| / _--=> preempt-depth
1769   # latency: 161 us, #339/339, CPU#3 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
1781   #                ||| / _--=> preempt-depth
1885   # latency: 15 us, #4/4, CPU#3 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
1894   #                ||| / _--=> preempt-depth
1954   # latency: 5 us, #4/4, CPU#3 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
1963   #                ||| / _--=> preempt-depth
2003   # latency: 29 us, #85/85, CPU#3 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
2012   #                ||| / _--=> preempt-depth
2129   # latency: 6 us, #12/12, CPU#2 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
2138   #                ||| / _--=> preempt-depth
2175   #                            || / _--=> preempt-depth
2274   #                            || / _--=> preempt-depth
2782   #                            || / _--=> preempt-depth
2829   #                            || / _--=> preempt-depth
2907   # echo '*preempt*' '*lock*' > set_ftrace_notrace
2918   #                            || / _--=> preempt-depth
2935 We can see that there's no more lock or preempt tracing.
3200   #                            || / _--=> preempt-depth
3332   #                            || / _--=> preempt-depth
3349   #                            || / _--=> preempt-depth
3465   #                            || / _--=> preempt-depth