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diff --git a/ANDROID_3.4.5/tools/perf/Documentation/perf-script-perl.txt b/ANDROID_3.4.5/tools/perf/Documentation/perf-script-perl.txt deleted file mode 100644 index 3152cca1..00000000 --- a/ANDROID_3.4.5/tools/perf/Documentation/perf-script-perl.txt +++ /dev/null @@ -1,216 +0,0 @@ -perf-script-perl(1) -================== - -NAME ----- -perf-script-perl - Process trace data with a Perl script - -SYNOPSIS --------- -[verse] -'perf script' [-s [Perl]:script[.pl] ] - -DESCRIPTION ------------ - -This perf script option is used to process perf script data using perf's -built-in Perl interpreter. It reads and processes the input file and -displays the results of the trace analysis implemented in the given -Perl script, if any. - -STARTER SCRIPTS ---------------- - -You can avoid reading the rest of this document by running 'perf script --g perl' in the same directory as an existing perf.data trace file. -That will generate a starter script containing a handler for each of -the event types in the trace file; it simply prints every available -field for each event in the trace file. - -You can also look at the existing scripts in -~/libexec/perf-core/scripts/perl for typical examples showing how to -do basic things like aggregate event data, print results, etc. Also, -the check-perf-script.pl script, while not interesting for its results, -attempts to exercise all of the main scripting features. - -EVENT HANDLERS --------------- - -When perf script is invoked using a trace script, a user-defined -'handler function' is called for each event in the trace. If there's -no handler function defined for a given event type, the event is -ignored (or passed to a 'trace_handled' function, see below) and the -next event is processed. - -Most of the event's field values are passed as arguments to the -handler function; some of the less common ones aren't - those are -available as calls back into the perf executable (see below). - -As an example, the following perf record command can be used to record -all sched_wakeup events in the system: - - # perf record -a -e sched:sched_wakeup - -Traces meant to be processed using a script should be recorded with -the above option: -a to enable system-wide collection. - -The format file for the sched_wakep event defines the following fields -(see /sys/kernel/debug/tracing/events/sched/sched_wakeup/format): - ----- - format: - field:unsigned short common_type; - field:unsigned char common_flags; - field:unsigned char common_preempt_count; - field:int common_pid; - - field:char comm[TASK_COMM_LEN]; - field:pid_t pid; - field:int prio; - field:int success; - field:int target_cpu; ----- - -The handler function for this event would be defined as: - ----- -sub sched::sched_wakeup -{ - my ($event_name, $context, $common_cpu, $common_secs, - $common_nsecs, $common_pid, $common_comm, - $comm, $pid, $prio, $success, $target_cpu) = @_; -} ----- - -The handler function takes the form subsystem::event_name. - -The $common_* arguments in the handler's argument list are the set of -arguments passed to all event handlers; some of the fields correspond -to the common_* fields in the format file, but some are synthesized, -and some of the common_* fields aren't common enough to to be passed -to every event as arguments but are available as library functions. - -Here's a brief description of each of the invariant event args: - - $event_name the name of the event as text - $context an opaque 'cookie' used in calls back into perf - $common_cpu the cpu the event occurred on - $common_secs the secs portion of the event timestamp - $common_nsecs the nsecs portion of the event timestamp - $common_pid the pid of the current task - $common_comm the name of the current process - -All of the remaining fields in the event's format file have -counterparts as handler function arguments of the same name, as can be -seen in the example above. - -The above provides the basics needed to directly access every field of -every event in a trace, which covers 90% of what you need to know to -write a useful trace script. The sections below cover the rest. - -SCRIPT LAYOUT -------------- - -Every perf script Perl script should start by setting up a Perl module -search path and 'use'ing a few support modules (see module -descriptions below): - ----- - use lib "$ENV{'PERF_EXEC_PATH'}/scripts/perl/perf-script-Util/lib"; - use lib "./perf-script-Util/lib"; - use Perf::Trace::Core; - use Perf::Trace::Context; - use Perf::Trace::Util; ----- - -The rest of the script can contain handler functions and support -functions in any order. - -Aside from the event handler functions discussed above, every script -can implement a set of optional functions: - -*trace_begin*, if defined, is called before any event is processed and -gives scripts a chance to do setup tasks: - ----- - sub trace_begin - { - } ----- - -*trace_end*, if defined, is called after all events have been - processed and gives scripts a chance to do end-of-script tasks, such - as display results: - ----- -sub trace_end -{ -} ----- - -*trace_unhandled*, if defined, is called after for any event that - doesn't have a handler explicitly defined for it. The standard set - of common arguments are passed into it: - ----- -sub trace_unhandled -{ - my ($event_name, $context, $common_cpu, $common_secs, - $common_nsecs, $common_pid, $common_comm) = @_; -} ----- - -The remaining sections provide descriptions of each of the available -built-in perf script Perl modules and their associated functions. - -AVAILABLE MODULES AND FUNCTIONS -------------------------------- - -The following sections describe the functions and variables available -via the various Perf::Trace::* Perl modules. To use the functions and -variables from the given module, add the corresponding 'use -Perf::Trace::XXX' line to your perf script script. - -Perf::Trace::Core Module -~~~~~~~~~~~~~~~~~~~~~~~~ - -These functions provide some essential functions to user scripts. - -The *flag_str* and *symbol_str* functions provide human-readable -strings for flag and symbolic fields. These correspond to the strings -and values parsed from the 'print fmt' fields of the event format -files: - - flag_str($event_name, $field_name, $field_value) - returns the string represention corresponding to $field_value for the flag field $field_name of event $event_name - symbol_str($event_name, $field_name, $field_value) - returns the string represention corresponding to $field_value for the symbolic field $field_name of event $event_name - -Perf::Trace::Context Module -~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -Some of the 'common' fields in the event format file aren't all that -common, but need to be made accessible to user scripts nonetheless. - -Perf::Trace::Context defines a set of functions that can be used to -access this data in the context of the current event. Each of these -functions expects a $context variable, which is the same as the -$context variable passed into every event handler as the second -argument. - - common_pc($context) - returns common_preempt count for the current event - common_flags($context) - returns common_flags for the current event - common_lock_depth($context) - returns common_lock_depth for the current event - -Perf::Trace::Util Module -~~~~~~~~~~~~~~~~~~~~~~~~ - -Various utility functions for use with perf script: - - nsecs($secs, $nsecs) - returns total nsecs given secs/nsecs pair - nsecs_secs($nsecs) - returns whole secs portion given nsecs - nsecs_nsecs($nsecs) - returns nsecs remainder given nsecs - nsecs_str($nsecs) - returns printable string in the form secs.nsecs - avg($total, $n) - returns average given a sum and a total number of values - -SEE ALSO --------- -linkperf:perf-script[1] |