OpenMP Logs

Logging library for OpenMP

Link to the repository: omp-logs

Compilation

You can compile the lib by doing make

Then, you can use this lib from anywhere. The builds will look like:

gcc file.c -o file.o -L/path -lomp_logs

where path is the path to the directory where you built the lib.

#include "path/to/the/file/omp_logs.h"

This list needs to be accessible by every call of the function log_task.

You can put the list as a global variable to be sure.

task_list* list = NULL;

or with

task_list* list = task_list_init();

The function to log a task is:

void log_task(task_list** l, char* label, int info, int parent_id, void (*f)(void* args), void* args)

l is the list of tasks that we created just before
label is the label that you could give to the task
info is a placeholder for some info that you could want to have (i.e. size of an array, index, …)
parent_id is the id of the thread that is the parent of the thread running the task. You can get this id by doing omp_get_thread_num() before creating the task
f is the function that represents the task. It must be of type void (*f)(void* args)
args is the argument(s) of f

I invite you to look at the examples mergesort.c and for_policies.c

When all the parallel stuff is done, you can get the logs in a svg file:

 tasks_to_svg(l, "filename.svg", x);

with x = 0 if you don’t want a svg file with script, x = 1 otherwise.

This will also free the list l.

Even if this is a svg file, you’ll have to open it with your browser.

Here is an example (For the full experience: click on the image, and then, right click -> “View Image”):

example

Every line represents a thread across time.

Every rectangle is a task.

You can move your mouse on it to see some info:

Have a x86 architecture…

This work is highly inspired from wagnerf42’s rayon-logs