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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 | libtraceevent(3) ================ NAME ---- tep_data_type, tep_data_pid,tep_data_preempt_count, tep_data_flags - Extract common fields from a record. SYNOPSIS -------- [verse] -- *#include <event-parse.h>* enum *trace_flag_type* { _TRACE_FLAG_IRQS_OFF_, _TRACE_FLAG_IRQS_NOSUPPORT_, _TRACE_FLAG_NEED_RESCHED_, _TRACE_FLAG_HARDIRQ_, _TRACE_FLAG_SOFTIRQ_, }; int *tep_data_type*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_); int *tep_data_pid*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_); int *tep_data_preempt_count*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_); int *tep_data_flags*(struct tep_handle pass:[*]_tep_, struct tep_record pass:[*]_rec_); -- DESCRIPTION ----------- This set of functions can be used to extract common fields from a record. The _tep_data_type()_ function gets the event id from the record _rec_. It reads the "common_type" field. The _tep_ argument is the trace event parser context. The _tep_data_pid()_ function gets the process id from the record _rec_. It reads the "common_pid" field. The _tep_ argument is the trace event parser context. The _tep_data_preempt_count()_ function gets the preemption count from the record _rec_. It reads the "common_preempt_count" field. The _tep_ argument is the trace event parser context. The _tep_data_flags()_ function gets the latency flags from the record _rec_. It reads the "common_flags" field. The _tep_ argument is the trace event parser context. Supported latency flags are: [verse] -- _TRACE_FLAG_IRQS_OFF_, Interrupts are disabled. _TRACE_FLAG_IRQS_NOSUPPORT_, Reading IRQ flag is not supported by the architecture. _TRACE_FLAG_NEED_RESCHED_, Task needs rescheduling. _TRACE_FLAG_HARDIRQ_, Hard IRQ is running. _TRACE_FLAG_SOFTIRQ_, Soft IRQ is running. -- RETURN VALUE ------------ The _tep_data_type()_ function returns an integer, representing the event id. The _tep_data_pid()_ function returns an integer, representing the process id The _tep_data_preempt_count()_ function returns an integer, representing the preemption count. The _tep_data_flags()_ function returns an integer, representing the latency flags. Look at the _trace_flag_type_ enum for supported flags. All these functions in case of an error return a negative integer. EXAMPLE ------- [source,c] -- #include <event-parse.h> ... struct tep_handle *tep = tep_alloc(); ... void process_record(struct tep_record *record) { int data; data = tep_data_type(tep, record); if (data >= 0) { /* Got the ID of the event */ } data = tep_data_pid(tep, record); if (data >= 0) { /* Got the process ID */ } data = tep_data_preempt_count(tep, record); if (data >= 0) { /* Got the preemption count */ } data = tep_data_flags(tep, record); if (data >= 0) { /* Got the latency flags */ } } ... -- FILES ----- [verse] -- *event-parse.h* Header file to include in order to have access to the library APIs. *-ltraceevent* Linker switch to add when building a program that uses the library. -- SEE ALSO -------- _libtraceevent(3)_, _trace-cmd(1)_ AUTHOR ------ [verse] -- *Steven Rostedt* <rostedt@goodmis.org>, author of *libtraceevent*. *Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>, author of this man page. -- REPORTING BUGS -------------- Report bugs to <linux-trace-devel@vger.kernel.org> LICENSE ------- libtraceevent is Free Software licensed under the GNU LGPL 2.1 RESOURCES --------- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git |