| 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 |
