pmm_executor.c File Reference

Functions for executing a benchmark. More...

#include <stdlib.h>
#include <signal.h>
#include <sys/signal.h>
#include <pthread.h>
#include <sys/time.h>
#include <sys/types.h>
#include <time.h>
#include <paths.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <libgen.h>
#include "pmm_model.h"
#include "pmm_selector.h"
#include "pmm_cfgparser.h"
#include "pmm_log.h"
#include "pmm_util.h"

Go to the source code of this file.

Functions
int	my_popen (char *cmd, char **args, int n, pid_t *pid)
int	set_non_blocking (int fd)
struct pmm_benchmark *	parse_bench_output (char *output, int n_p, int *rargs)
int	read_benchmark_output (int fd, char **output_p, pid_t bench_pid)
void	sig_childexit (int sig)
double	calculate_flops (struct timeval tv, long long int complexity)
double	timeval_to_seconds (struct timeval tv)
void	set_executing_benchmark (int i)
char *	pmm_bench_exit_status_to_string (int bench_status)
int	spawn_benchmark_process (struct pmm_routine *r, int *params, pid_t *bench_pid)
void	cleanup_benchmark_process (FILE *fp, pid_t bench_pid)
void *	benchmark (void *scheduled_r)

Variables
int	executing_benchmark
	daemon executing variable or not
pthread_mutex_t	executing_benchmark_mutex
	mutex for accessing executing_benchmark variable
int	signal_quit
	signal to indicate benchmark should be terminated
pthread_mutex_t	signal_quit_mutex
	mutex for accessing singal_quit

Detailed Description

Functions for executing a benchmark.

This file contains code for calling a benchmark executable from the pmm daemon, dealing with the system level requirements of spawning the benchmark process and parsing the output of said benchmark.

Definition in file pmm_executor.c.

Function Documentation

void* benchmark

(

void *

scheduled_r

)

Given a routine to benchmark, select a point, execute the benchmark and insert the new point into the model. Set the global 'executing_benchark' to false/0 when the operation is complete (or has failed).

Parameters

scheduled_r

void pointer to a routine structure that has been scheduled for a benchmark execution

Returns

void pointer to an integer with value of: 0 on success, 1 on quit from signal, -1 on failure

Definition at line 685 of file pmm_executor.c.

double calculate_flops	(	struct timeval	tv,
		long long int	complexity
	)

calculate (FL)OPS (floating point operations per second or any other type of operations per second)

Parameters

tv	timeval structure representing duration of computation
complexity	complexity of computation (volume of operations)

Returns

flops as a double

Definition at line 304 of file pmm_executor.c.

void cleanup_benchmark_process	(	FILE *	fp,
		pid_t	bench_pid
	)

clean up a benchmark process

closes file handles and kills the process

Parameters

fp	file pointer to the benchmarks standard output
bench_pid	benchmark process id

Definition at line 465 of file pmm_executor.c.

int my_popen	(	char *	cmd,
		char **	args,
		int	n,
		pid_t *	pid
	)

Forks a process that executes and external program with a an argument string and returns a file distriptor and sets the child processes pid

Parameters

cmd	string with the full path of the program
args	array of strings with all arguments of the program
n	number of arguments in arg vector
pid	pointer to the pid which will be set to the pid of the external program

Returns

file descriptor of the pipe opened to the command cmd.

TODO test for file not found

Definition at line 134 of file pmm_executor.c.

struct pmm_benchmark * parse_bench_output ( char *  output, int  n_p, int *  rargs  )

read

Given the output of a benchmark execution parse and create a new benchmark structure storing all the information gained

Parameters

output	pointer to benchmark output string
n_p	number of parameters of benchmark
rargs	arguments passed to the benchmarked routine

Returns

pointer to newly allocated benchmark reflecting the parsed output

Definition at line 233 of file pmm_executor.c.

char * pmm_bench_exit_status_to_string

(

int

bench_status

)

convert benchmark exit status to a string

Parameters

bench_status

benchmark status represented by an int

Returns

pointer to a character string

Definition at line 970 of file pmm_executor.c.

int read_benchmark_output	(	int	fd,
		char **	output_p,
		pid_t	bench_pid
	)

Read the output of a benchmark process

Parameters

fd	benchmark process output file descriptor
output_p	pointer to a character array where output will be stored
bench_pid	process id of the benchmark process

Returns

0 on success, -1 if there was an error reading (output_p also set to NULL) 1 if a quit signal was received while waiting for output

Definition at line 490 of file pmm_executor.c.

void set_executing_benchmark

(

int

i

)

set the executing_benchmark variable via mutex

Parameters

i	value to set variable with

Definition at line 952 of file pmm_executor.c.

int set_non_blocking

(

int

fd

)

a roughly portable way of setting a file descriptor for non-blocking I/O.

Parameters

fd	file descriptor to modify

Returns

-1 on error, 0 on success

Definition at line 94 of file pmm_executor.c.

void sig_childexit

(

int

sig

)

SIGCHLD signal handler

Parameters

sig	the signal

Warning

Do not use *PRINTF logging facility in this thread, it is not 'async-signal-safe' (though it is threadsafe).

Definition at line 212 of file pmm_executor.c.

int spawn_benchmark_process	(	struct pmm_routine *	r,
		int *	params,
		pid_t *	bench_pid
	)

Convert params to an array of strings and call my_popen

Parameters

r	pointer to routine that will be executed
params	pointer to array of parameters
bench_pid	pointer to pid_t to store spawned process pid

Returns

int index of file descriptor that points to the stdout of the spawned process, or -1 if there is an error

Definition at line 332 of file pmm_executor.c.

double timeval_to_seconds

(

struct timeval

tv

)

convert a timeval to second in double

Parameters

tv	timeval structure

Returns

timeval as seconds

Definition at line 316 of file pmm_executor.c.

Variable Documentation

int executing_benchmark

daemon executing variable or not

Definition at line 54 of file pmm_main.c.

pthread_mutex_t executing_benchmark_mutex

mutex for accessing executing_benchmark variable

Definition at line 55 of file pmm_main.c.

int signal_quit

signal to indicate benchmark should be terminated

Definition at line 57 of file pmm_main.c.

pthread_mutex_t signal_quit_mutex

mutex for accessing singal_quit

Definition at line 58 of file pmm_main.c.