Most shell command snippets (echo/cat) and their output are already in literal code blocks. However a few still isn't wrapped, in which the htmldocs output is ugly. Wrap the remaining unwrapped snippets, while also fix recent kernel test robot warnings. Link: https://lore.kernel.org/linux-doc/202301290253.LU5yIxcJ-lkp@xxxxxxxxx/ Fixes: 88238513bb2671 ("tracing/histogram: Document variable stacktrace") Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Bagas Sanjaya <bagasdotme@xxxxxxxxx> --- Documentation/trace/histogram.rst | 93 ++++++++++++++++--------------- 1 file changed, 47 insertions(+), 46 deletions(-) diff --git a/Documentation/trace/histogram.rst b/Documentation/trace/histogram.rst index 5c391328b9bb41..8e95295e39b65c 100644 --- a/Documentation/trace/histogram.rst +++ b/Documentation/trace/histogram.rst @@ -1864,7 +1864,7 @@ A histogram can now be defined for the new synthetic event:: The above shows the latency "lat" in a power of 2 grouping. Like any other event, once a histogram is enabled for the event, the -output can be displayed by reading the event's 'hist' file. +output can be displayed by reading the event's 'hist' file:: # cat /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/hist @@ -1911,7 +1911,7 @@ output can be displayed by reading the event's 'hist' file. The latency values can also be grouped linearly by a given size with -the ".buckets" modifier and specify a size (in this case groups of 10). +the ".buckets" modifier and specify a size (in this case groups of 10):: # echo 'hist:keys=pid,prio,lat.buckets=10:sort=lat' >> \ /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger @@ -1945,7 +1945,7 @@ the ".buckets" modifier and specify a size (in this case groups of 10). To save stacktraces, create a synthetic event with a field of type "unsigned long[]" or even just "long[]". For example, to see how long a task is blocked in an -uninterruptible state: +uninterruptible state:: # cd /sys/kernel/tracing # echo 's:block_lat pid_t pid; u64 delta; unsigned long[] stack;' > dynamic_events @@ -1990,7 +1990,8 @@ uninterruptible state: => kthread+0xe9/0x110 => ret_from_fork+0x2c/0x50 -A synthetic event that has a stacktrace field may use it as a key in histogram: +A synthetic event that has a stacktrace field may use it as a key in +histogram:: # echo 'hist:delta.buckets=100,stack.stacktrace:sort=delta' > events/synthetic/block_lat/trigger # cat events/synthetic/block_lat/hist @@ -2183,11 +2184,11 @@ The following commonly-used handler.action pairs are available: wakeup_new_test($testpid) if comm=="cyclictest"' >> \ /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger - Or, equivalently, using the 'trace' keyword syntax: + Or, equivalently, using the 'trace' keyword syntax:: - # echo 'hist:keys=$testpid:testpid=pid:onmatch(sched.sched_wakeup_new).\ - trace(wakeup_new_test,$testpid) if comm=="cyclictest"' >> \ - /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger + # echo 'hist:keys=$testpid:testpid=pid:onmatch(sched.sched_wakeup_new).\ + trace(wakeup_new_test,$testpid) if comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger Creating and displaying a histogram based on those events is now just a matter of using the fields and new synthetic event in the @@ -2320,48 +2321,48 @@ The following commonly-used handler.action pairs are available: resulting latency, stored in wakeup_lat, exceeds the current maximum latency, a snapshot is taken. As part of the setup, all the scheduler events are also enabled, which are the events that - will show up in the snapshot when it is taken at some point: + will show up in the snapshot when it is taken at some point:: - # echo 1 > /sys/kernel/debug/tracing/events/sched/enable + # echo 1 > /sys/kernel/debug/tracing/events/sched/enable - # echo 'hist:keys=pid:ts0=common_timestamp.usecs \ - if comm=="cyclictest"' >> \ - /sys/kernel/debug/tracing/events/sched/sched_waking/trigger + # echo 'hist:keys=pid:ts0=common_timestamp.usecs \ + if comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_waking/trigger - # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0: \ - onmax($wakeup_lat).save(next_prio,next_comm,prev_pid,prev_prio, \ - prev_comm):onmax($wakeup_lat).snapshot() \ - if next_comm=="cyclictest"' >> \ - /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0: \ + onmax($wakeup_lat).save(next_prio,next_comm,prev_pid,prev_prio, \ + prev_comm):onmax($wakeup_lat).snapshot() \ + if next_comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_switch/trigger When the histogram is displayed, for each bucket the max value and the saved values corresponding to the max are displayed following the rest of the fields. If a snapshot was taken, there is also a message indicating that, - along with the value and event that triggered the global maximum: + along with the value and event that triggered the global maximum:: - # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist - { next_pid: 2101 } hitcount: 200 - max: 52 next_prio: 120 next_comm: cyclictest \ - prev_pid: 0 prev_prio: 120 prev_comm: swapper/6 + # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist + { next_pid: 2101 } hitcount: 200 + max: 52 next_prio: 120 next_comm: cyclictest \ + prev_pid: 0 prev_prio: 120 prev_comm: swapper/6 - { next_pid: 2103 } hitcount: 1326 - max: 572 next_prio: 19 next_comm: cyclictest \ - prev_pid: 0 prev_prio: 120 prev_comm: swapper/1 + { next_pid: 2103 } hitcount: 1326 + max: 572 next_prio: 19 next_comm: cyclictest \ + prev_pid: 0 prev_prio: 120 prev_comm: swapper/1 - { next_pid: 2102 } hitcount: 1982 \ - max: 74 next_prio: 19 next_comm: cyclictest \ - prev_pid: 0 prev_prio: 120 prev_comm: swapper/5 + { next_pid: 2102 } hitcount: 1982 \ + max: 74 next_prio: 19 next_comm: cyclictest \ + prev_pid: 0 prev_prio: 120 prev_comm: swapper/5 - Snapshot taken (see tracing/snapshot). Details: - triggering value { onmax($wakeup_lat) }: 572 \ - triggered by event with key: { next_pid: 2103 } + Snapshot taken (see tracing/snapshot). Details: + triggering value { onmax($wakeup_lat) }: 572 \ + triggered by event with key: { next_pid: 2103 } - Totals: - Hits: 3508 - Entries: 3 - Dropped: 0 + Totals: + Hits: 3508 + Entries: 3 + Dropped: 0 In the above case, the event that triggered the global maximum has the key with next_pid == 2103. If you look at the bucket that has @@ -2439,15 +2440,15 @@ The following commonly-used handler.action pairs are available: $cwnd variable. If the value has changed, a snapshot is taken. As part of the setup, all the scheduler and tcp events are also enabled, which are the events that will show up in the snapshot - when it is taken at some point: + when it is taken at some point:: - # echo 1 > /sys/kernel/debug/tracing/events/sched/enable - # echo 1 > /sys/kernel/debug/tracing/events/tcp/enable + # echo 1 > /sys/kernel/debug/tracing/events/sched/enable + # echo 1 > /sys/kernel/debug/tracing/events/tcp/enable - # echo 'hist:keys=dport:cwnd=snd_cwnd: \ - onchange($cwnd).save(snd_wnd,srtt,rcv_wnd): \ - onchange($cwnd).snapshot()' >> \ - /sys/kernel/debug/tracing/events/tcp/tcp_probe/trigger + # echo 'hist:keys=dport:cwnd=snd_cwnd: \ + onchange($cwnd).save(snd_wnd,srtt,rcv_wnd): \ + onchange($cwnd).snapshot()' >> \ + /sys/kernel/debug/tracing/events/tcp/tcp_probe/trigger When the histogram is displayed, for each bucket the tracked value and the saved values corresponding to that value are displayed @@ -2470,10 +2471,10 @@ The following commonly-used handler.action pairs are available: { dport: 443 } hitcount: 211 changed: 10 snd_wnd: 26960 srtt: 17379 rcv_wnd: 28800 - Snapshot taken (see tracing/snapshot). Details:: + Snapshot taken (see tracing/snapshot). Details: - triggering value { onchange($cwnd) }: 10 - triggered by event with key: { dport: 80 } + triggering value { onchange($cwnd) }: 10 + triggered by event with key: { dport: 80 } Totals: Hits: 414 base-commit: 9f712417e1fc7d3db042941524e59573e02a55c7 -- An old man doll... just what I always wanted! - Clara
