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           trace-cmd report [OPTIONS] [input-file]


           The trace-cmd(1) report command will output a human readable report of
           a trace created by trace-cmd record.


           -i input-file
               By default, trace-cmd report will read the file trace.dat. But the
               -i option open up the given input-file instead. Note, the input
               file may also be specified as the last item on the command line.
               This outputs the endianess of the file. trace-cmd report is smart
               enough to be able to read big endian files on little endian
               machines, and vise versa.
               This outputs the list of functions that have been recorded in the
               This outputs the list of "trace_printk()" data. The raw trace data
               points to static pointers in the kernel. This must be stored in the
               trace.dat file.
               This lists the possible events in the file (but this list is not
               necessarily the list of events in the file).
               This will list the event formats that are stored in the trace.dat
           -F filter
               Add a filter to limit what events are displayed. The format of the
               filter is:
                   <events> ':' <filter>
                   <events> = SYSTEM'/'EVENT  | SYSTEM | EVENT | <events> ',' <events>
                   <filter> = EVENT_FIELD <op> <value> | <filter> '&&' <filter> |
                              <filter> '||' <filter> | '(' <filter> ')' | '!' <filter>
                   <op> = '==' | '!=' | '>=' | '<=' | '>' | '<' | '&' | '|' | '^' |
                          '+' | '-' | '*' | '/' | '%'
                   <value> = NUM | STRING | EVENT_FIELD
               SYSTEM is the name of the system to filter on. If the EVENT is left out,
               then it applies to all events under the SYSTEM. If only one string is used
               without the '/' to deliminate between SYSTEM and EVENT, then the filter
               will be applied to all systems and events that match the given string.
                   -F 'sched : bogus == 1 || common_pid == 2'
               The "bogus == 1" will always evaluate to FALSE because no event has a
               field called "bogus", but the "common_pid == 2" will still be evaluated
               since all events have the field "common_pid". Any "sched" event that was
               traced by the process with the PID of 2 will be shown.
               Note, the EVENT_FIELD is the field name as shown by an events format
               (as displayed with *--events*), and not what is found in the output.
               If the output shows "ID:foo" but the field that "foo" belongs to was
               called "name" in the event format, then "name" must be used in the filter.
               The same is true about values. If the value that is displayed is converted
               by to a string symbol, the filter checks the original value and not the
               value displayed. For example, to filter on all tasks that were in the
               running state at a context switch:
                   -F 'sched/sched_switch : prev_state==0'
               Although the output displays 'R', having 'prev_stat=="R"' will not work.
               This causes the following filters of -F to filter out the matching
                   -v -F 'sched/sched_switch : prev_state == 0'
               Will not display any sched_switch events that have a prev_state of 0.
               Removing the *-v* will only print out those events.
               Show the plugins that are loaded.
               This will not load system wide plugins. It loads "local only". That
               is what it finds in the ~/.trace-cmd/plugins directory.
               This will not load any plugins.
               This will show the events in "raw" format. That is, it will ignore
               the event's print formatting and just print the contents of each
               This adds a "latency output" format. Information about interrupts
               being disabled, soft irq being disabled, the "need_resched" flag
               being set, preempt count, and big kernel lock are all being
               recorded with every event. But the default display does not show
               this information. This option will set display this information
               with 6 characters. When one of the fields is zero or N/A a '.\' is
               first woken, and the time it was scheduled in.
               Quiet non critical warnings.


           Using a trace.dat file that was created with:
                   # trace-cmd record -p function -e all sleep 5
           The default report shows:
                # trace-cmd report
                      trace-cmd-16129 [002] 158126.498411: function: __mutex_unlock_slowpath <-- mutex_unlock
                      trace-cmd-16131 [000] 158126.498411: kmem_cache_alloc: call_site=811223c5 ptr=0xffff88003ecf2b40 bytes_req=272 bytes_alloc=320 gfp_flags=GFP_KERNEL|GFP_ZERO
                      trace-cmd-16130 [003] 158126.498411: function:             do_splice_to <-- sys_splice
                          sleep-16133 [001] 158126.498412: function: inotify_inode_queue_event <-- vfs_write
                      trace-cmd-16129 [002] 158126.498420: lock_release: 0xffff88003f1fa4f8 &sb->s_type->i_mutex_key
                      trace-cmd-16131 [000] 158126.498421: function: security_file_alloc <-- get_empty_filp
                          sleep-16133 [001] 158126.498422: function: __fsnotify_parent <-- vfs_write
                      trace-cmd-16130 [003] 158126.498422: function: rw_verify_area <-- do_splice_to
                      trace-cmd-16131 [000] 158126.498424: function: cap_file_alloc_security <-- security_file_alloc
                      trace-cmd-16129 [002] 158126.498425: function: syscall_trace_leave <-- int_check_syscall_exit_work
                          sleep-16133 [001] 158126.498426: function: inotify_dentry_parent_queue_event <-- vfs_write
                      trace-cmd-16130 [003] 158126.498426: function: security_file_permission <-- rw_verify_area
                      trace-cmd-16129 [002] 158126.498428: function: audit_syscall_exit <-- syscall_trace_leave
           To see everything but the function traces:
                # trace-cmd report -v -F 'function'
                      trace-cmd-16131 [000] 158126.498411: kmem_cache_alloc: call_site=811223c5 ptr=0xffff88003ecf2b40 bytes_req=272 bytes_alloc=320 gfp_flags=GFP_KERNEL|GFP_ZERO
                      trace-cmd-16129 [002] 158126.498420: lock_release: 0xffff88003f1fa4f8 &sb->s_type->i_mutex_key
                      trace-cmd-16130 [003] 158126.498436: lock_acquire: 0xffffffff8166bf78 read all_cpu_access_lock
                      trace-cmd-16131 [000] 158126.498438: lock_acquire: 0xffff88003df5b520 read &fs->lock
                      trace-cmd-16129 [002] 158126.498446: kfree: call_site=810a7abb ptr=0x0
                      trace-cmd-16130 [003] 158126.498448: lock_acquire: 0xffff880002250a80 &per_cpu(cpu_access_lock, cpu)
                      trace-cmd-16129 [002] 158126.498450: sys_exit_splice:      0xfffffff5
                      trace-cmd-16131 [000] 158126.498454: lock_release: 0xffff88003df5b520 &fs->lock
                          sleep-16133 [001] 158126.498456: kfree: call_site=810a7abb ptr=0x0
                          sleep-16133 [001] 158126.498460: sys_exit_write:       0x1
                      trace-cmd-16130 [003] 158126.498462: kmalloc: call_site=810bf95b ptr=0xffff88003dedc040 bytes_req=24 bytes_alloc=32 gfp_flags=GFP_KERNEL|GFP_ZERO
           To see only the kmalloc calls that were greater than 1000 bytes:
                #trace-cmd report -F 'kmalloc: bytes_req > 1000'
                         <idle>-0     [000] 158128.126641: kmalloc: call_site=81330635 ptr=0xffff88003c2fd000 bytes_req=2096 bytes_alloc=4096 gfp_flags=GFP_ATOMIC
           To see wakeups and sched switches that left the previous task in the
           running state:
                # trace-cmd report -F 'sched: prev_state == 0 || (success == 1)'
           Any event that does not have the format field "prev_state" or
           "success", will evaluate those expressions as FALSE, and will not
           produce a match. Using "||" will have the "prev_state" test happen for
           the "sched_switch" event and the "success" test happen for the
           "sched_wakeup" event.
                 # trace-cmd report -w -F 'sched_switch, sched_wakeup.*'
                      trace-cmd-16130 [003] 158131.580616: sched_wakeup: comm=trace-cmd pid=16131 prio=120 success=1 target_cpu=003
                      trace-cmd-16129 [000] 158131.581502: sched_switch: prev_comm=trace-cmd prev_pid=16129 prev_prio=120 prev_state=S ==> next_comm=trace-cmd next_pid=16131 next_prio=120 Latency: 885.901 usecs
                      trace-cmd-16131 [000] 158131.582414: sched_wakeup: comm=trace-cmd pid=16129 prio=120 success=1 target_cpu=000
                      trace-cmd-16132 [001] 158131.583219: sched_switch: prev_comm=trace-cmd prev_pid=16132 prev_prio=120 prev_state=S ==> next_comm=trace-cmd next_pid=16129 next_prio=120 Latency: 804.809 usecs
                          sleep-16133 [002] 158131.584121: sched_wakeup: comm=trace-cmd pid=16120 prio=120 success=1 target_cpu=002
                      trace-cmd-16129 [001] 158131.584128: sched_wakeup: comm=trace-cmd pid=16132 prio=120 success=1 target_cpu=001
                          sleep-16133 [002] 158131.584275: sched_switch: prev_comm=sleep prev_pid=16133 prev_prio=120 prev_state=R ==> next_comm=trace-cmd next_pid=16120 next_prio=120 Latency: 153.915 usecs
                      trace-cmd-16130 [003] 158131.585284: sched_switch: prev_comm=trace-cmd prev_pid=16130 prev_prio=120 prev_state=S ==> next_comm=trace-cmd next_pid=16132 next_prio=120 Latency: 1155.677 usecs
               Average wakeup latency: 26626.656 usecs
           The above trace produces the wakeup latencies of the tasks. The
           "sched_switch" event reports each individual latency after writing the
           event information. At the end of the report, the average wakeup latency
           is reported.
                 # trace-cmd report -w -F 'sched_switch, sched_wakeup.*: prio < 100 || next_prio < 100'
                         <idle>-0     [003] 158131.516753: sched_wakeup: comm=ksoftirqd/3 pid=13 prio=49 success=1 target_cpu=003
                         <idle>-0     [003] 158131.516855: sched_switch: prev_comm=swapper prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=ksoftirqd/3 next_pid=13 next_prio=49 Latency: 101.244 usecs
                         <idle>-0     [003] 158131.533781: sched_wakeup: comm=ksoftirqd/3 pid=13 prio=49 success=1 target_cpu=003
                         <idle>-0     [003] 158131.533897: sched_switch: prev_comm=swapper prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=ksoftirqd/3 next_pid=13 next_prio=49 Latency: 115.608 usecs
                         <idle>-0     [003] 158131.569730: sched_wakeup: comm=ksoftirqd/3 pid=13 prio=49 success=1 target_cpu=003
                         <idle>-0     [003] 158131.569851: sched_switch: prev_comm=swapper prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=ksoftirqd/3 next_pid=13 next_prio=49 Latency: 121.024 usecs
               Average wakeup latency: 110.021 usecs
           The above version will only show the wakeups and context switches of
           Real Time tasks. The prio used inside the kernel starts at 0 for
           highest priority. That is prio 0 is equivalent to user space real time
           priority 99, and priority 98 is equivalent to user space real time
           priority 1. Prios less than 100 represent Real Time tasks.


           trace-cmd(1), trace-cmd-record(1), trace-cmd-start(1),
           trace-cmd-stop(1), trace-cmd-extract(1), trace-cmd-reset(1),
           trace-cmd-split(1), trace-cmd-list(1), trace-cmd-listen(1)


           Written by Steven Rostedt, <[1]>





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