diff options
Diffstat (limited to 'Documentation/trace/histogram-design.rst')
| -rw-r--r-- | Documentation/trace/histogram-design.rst | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/Documentation/trace/histogram-design.rst b/Documentation/trace/histogram-design.rst index eef840043da9..5765eb3e9efa 100644 --- a/Documentation/trace/histogram-design.rst +++ b/Documentation/trace/histogram-design.rst @@ -14,7 +14,7 @@ tracing_map.c. Note: All the ftrace histogram command examples assume the working directory is the ftrace /tracing directory. For example:: - # cd /sys/kernel/debug/tracing + # cd /sys/kernel/tracing Also, the histogram output displayed for those commands will be generally be truncated - only enough to make the point is displayed. @@ -780,7 +780,7 @@ same part of the hist_data->fields[] array as normal values:: Moving on to the sched_switch trigger hist_debug output, in addition to the unused wakeup_lat variable, we see a new section displaying variable references. Variable references are displayed in a separate -section because in addition to to being logically separate from +section because in addition to being logically separate from variables and values, they actually live in a separate hist_data array, var_refs[]. @@ -863,7 +863,7 @@ event. The onmatch() action below basically says that whenever we have a sched_switch event, if we have a matching sched_waking event, in this case if we have a pid in the sched_waking histogram that matches the -the next_pid field on this sched_switch event, we retrieve the +next_pid field on this sched_switch event, we retrieve the variables specified in the wakeup_latency() trace action, and use them to generate a new wakeup_latency event into the trace stream. @@ -905,7 +905,7 @@ means it will be automatically converted into a field variable:: # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0: \ onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid)' >> - /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + /sys/kernel/tracing/events/sched/sched_switch/trigger The diagram for the sched_switch event is similar to previous examples but shows the additional field_vars[] array for hist_data and shows @@ -1112,7 +1112,7 @@ sched_switch event fields, next_pid and next_comm, to generate a wakeup_latency trace event. The next_pid and next_comm event fields are automatically converted into field variables for this purpose:: - # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,next_comm)' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,next_comm)' >> /sys/kernel/tracing/events/sched/sched_switch/trigger The sched_waking hist_debug output shows the same data as in the previous test example:: @@ -1305,7 +1305,7 @@ and event name for the onmatch() handler:: The commands below can be used to clean things up for the next test:: - # echo '!hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,next_comm)' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + # echo '!hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,next_comm)' >> /sys/kernel/tracing/events/sched/sched_switch/trigger # echo '!hist:keys=pid:ts0=common_timestamp.usecs' >> events/sched/sched_waking/trigger @@ -1363,13 +1363,13 @@ with the save() and snapshot() actions. For example:: # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0: \ onmax($wakeup_lat).save(next_comm,prev_pid,prev_prio,prev_comm)' >> - /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + /sys/kernel/tracing/events/sched/sched_switch/trigger or:: # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0: \ onmax($wakeup_lat).snapshot()' >> - /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + /sys/kernel/tracing/events/sched/sched_switch/trigger save() action field variable test --------------------------------- |