// SPDX-License-Identifier: GPL-2.0/* * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira <bristot@kernel.org> */ #include <proc/readproc.h>#include <stdarg.h>#include <stdlib.h>#include <string.h>#include <unistd.h>#include <ctype.h>#include <errno.h>#include <fcntl.h>#include <sched.h>#include <stdio.h> #include "utils.h" #define MAX_MSG_LENGTH 1024int config_debug; /* * err_msg - print an error message to the stderr */void err_msg(const char *fmt, ...){ char message[MAX_MSG_LENGTH]; va_list ap; va_start(ap, fmt); vsnprintf(message, sizeof(message), fmt, ap); va_end(ap); fprintf(stderr, "%s", message);} /* * debug_msg - print a debug message to stderr if debug is set */void debug_msg(const char *fmt, ...){ char message[MAX_MSG_LENGTH]; va_list ap; if (!config_debug) return; va_start(ap, fmt); vsnprintf(message, sizeof(message), fmt, ap); va_end(ap); fprintf(stderr, "%s", message);} /* * get_llong_from_str - get a long long int from a string */long long get_llong_from_str(char *start){ long long value; char *end; errno = 0; value = strtoll(start, &end, 10); if (errno || start == end) return -1; return value;} /* * get_duration - fill output with a human readable duration since start_time */void get_duration(time_t start_time, char *output, int output_size){ time_t now = time(NULL); struct tm *tm_info; time_t duration; duration = difftime(now, start_time); tm_info = gmtime(&duration); snprintf(output, output_size, "%3d %02d:%02d:%02d", tm_info->tm_yday, tm_info->tm_hour, tm_info->tm_min, tm_info->tm_sec);} /* * parse_cpu_list - parse a cpu_list filling a char vector with cpus set * * Receives a cpu list, like 1-3,5 (cpus 1, 2, 3, 5), and then set the char * in the monitored_cpus. * * XXX: convert to a bitmask. */int parse_cpu_list(char *cpu_list, char **monitored_cpus){ char *mon_cpus; const char *p; int end_cpu; int nr_cpus; int cpu; int i; nr_cpus = sysconf(_SC_NPROCESSORS_CONF); mon_cpus = malloc(nr_cpus * sizeof(char)); memset(mon_cpus, 0, (nr_cpus * sizeof(char))); for (p = cpu_list; *p; ) { cpu = atoi(p); if (cpu < 0 || (!cpu && *p != '0') || cpu >= nr_cpus) goto err; while (isdigit(*p)) p++; if (*p == '-') { p++; end_cpu = atoi(p); if (end_cpu < cpu || (!end_cpu && *p != '0') || end_cpu >= nr_cpus) goto err; while (isdigit(*p)) p++; } else end_cpu = cpu; if (cpu == end_cpu) { debug_msg("cpu_list: adding cpu %d\n", cpu); mon_cpus[cpu] = 1; } else { for (i = cpu; i <= end_cpu; i++) { debug_msg("cpu_list: adding cpu %d\n", i); mon_cpus[i] = 1; } } if (*p == ',') p++; } *monitored_cpus = mon_cpus; return 0; err: debug_msg("Error parsing the cpu list %s", cpu_list); return 1;} /* * parse_duration - parse duration with s/m/h/d suffix converting it to seconds */long parse_seconds_duration(char *val){ char *end; long t; t = strtol(val, &end, 10); if (end) { switch (*end) { case 's': case 'S': break; case 'm': case 'M': t *= 60; break; case 'h': case 'H': t *= 60 * 60; break; case 'd': case 'D': t *= 24 * 60 * 60; break; } } return t;} /* * parse_ns_duration - parse duration with ns/us/ms/s converting it to nanoseconds */long parse_ns_duration(char *val){ char *end; long t; t = strtol(val, &end, 10); if (end) { if (!strncmp(end, "ns", 2)) { return t; } else if (!strncmp(end, "us", 2)) { t *= 1000; return t; } else if (!strncmp(end, "ms", 2)) { t *= 1000 * 1000; return t; } else if (!strncmp(end, "s", 1)) { t *= 1000 * 1000 * 1000; return t; } return -1; } return t;} /* * This is a set of helper functions to use SCHED_DEADLINE. */#ifdef __x86_64__# define __NR_sched_setattr 314# define __NR_sched_getattr 315#elif __i386__# define __NR_sched_setattr 351# define __NR_sched_getattr 352#elif __arm__# define __NR_sched_setattr 380# define __NR_sched_getattr 381#elif __aarch64__# define __NR_sched_setattr 274# define __NR_sched_getattr 275#elif __powerpc__# define __NR_sched_setattr 355# define __NR_sched_getattr 356#elif __s390x__# define __NR_sched_setattr 345# define __NR_sched_getattr 346#endif #define SCHED_DEADLINE 6 static inline int sched_setattr(pid_t pid, const struct sched_attr *attr, unsigned int flags) { return syscall(__NR_sched_setattr, pid, attr, flags);} static inline int sched_getattr(pid_t pid, struct sched_attr *attr, unsigned int size, unsigned int flags){ return syscall(__NR_sched_getattr, pid, attr, size, flags);} int __set_sched_attr(int pid, struct sched_attr *attr){ int flags = 0; int retval; retval = sched_setattr(pid, attr, flags); if (retval < 0) { err_msg("boost_with_deadline failed to boost pid %d: %s\n", pid, strerror(errno)); return 1; } return 0;}/* * set_comm_sched_attr - set sched params to threads starting with char *comm * * This function uses procps to list the currently running threads and then * set the sched_attr *attr to the threads that start with char *comm. It is * mainly used to set the priority to the kernel threads created by the * tracers. */int set_comm_sched_attr(const char *comm, struct sched_attr *attr){ int flags = PROC_FILLCOM | PROC_FILLSTAT; PROCTAB *ptp; proc_t task; int retval; ptp = openproc(flags); if (!ptp) { err_msg("error openproc()\n"); return -ENOENT; } memset(&task, 0, sizeof(task)); while (readproc(ptp, &task)) { retval = strncmp(comm, task.cmd, strlen(comm)); if (retval) continue; retval = __set_sched_attr(task.tid, attr); if (retval) goto out_err; } closeproc(ptp); return 0; out_err: closeproc(ptp); return 1;} #define INVALID_VAL (~0L)static long get_long_ns_after_colon(char *start){ long val = INVALID_VAL; /* find the ":" */ start = strstr(start, ":"); if (!start) return -1; /* skip ":" */ start++; val = parse_ns_duration(start); return val;} static long get_long_after_colon(char *start){ long val = INVALID_VAL; /* find the ":" */ start = strstr(start, ":"); if (!start) return -1; /* skip ":" */ start++; val = get_llong_from_str(start); return val;} /* * parse priority in the format: * SCHED_OTHER: * o:<prio> * O:<prio> * SCHED_RR: * r:<prio> * R:<prio> * SCHED_FIFO: * f:<prio> * F:<prio> * SCHED_DEADLINE: * d:runtime:period * D:runtime:period */int parse_prio(char *arg, struct sched_attr *sched_param){ long prio; long runtime; long period; memset(sched_param, 0, sizeof(*sched_param)); sched_param->size = sizeof(*sched_param); switch (arg[0]) { case 'd': case 'D': /* d:runtime:period */ if (strlen(arg) < 4) return -1; runtime = get_long_ns_after_colon(arg); if (runtime == INVALID_VAL) return -1; period = get_long_ns_after_colon(&arg[2]); if (period == INVALID_VAL) return -1; if (runtime > period) return -1; sched_param->sched_policy = SCHED_DEADLINE; sched_param->sched_runtime = runtime; sched_param->sched_deadline = period; sched_param->sched_period = period; break; case 'f': case 'F': /* f:prio */ prio = get_long_after_colon(arg); if (prio == INVALID_VAL) return -1; if (prio < sched_get_priority_min(SCHED_FIFO)) return -1; if (prio > sched_get_priority_max(SCHED_FIFO)) return -1; sched_param->sched_policy = SCHED_FIFO; sched_param->sched_priority = prio; break; case 'r': case 'R': /* r:prio */ prio = get_long_after_colon(arg); if (prio == INVALID_VAL) return -1; if (prio < sched_get_priority_min(SCHED_RR)) return -1; if (prio > sched_get_priority_max(SCHED_RR)) return -1; sched_param->sched_policy = SCHED_RR; sched_param->sched_priority = prio; break; case 'o': case 'O': /* o:prio */ prio = get_long_after_colon(arg); if (prio == INVALID_VAL) return -1; if (prio < sched_get_priority_min(SCHED_OTHER)) return -1; if (prio > sched_get_priority_max(SCHED_OTHER)) return -1; sched_param->sched_policy = SCHED_OTHER; sched_param->sched_priority = prio; break; default: return -1; } return 0;} /* * set_cpu_dma_latency - set the /dev/cpu_dma_latecy * * This is used to reduce the exit from idle latency. The value * will be reset once the file descriptor of /dev/cpu_dma_latecy * is closed. * * Return: the /dev/cpu_dma_latecy file descriptor */int set_cpu_dma_latency(int32_t latency){ int retval; int fd; fd = open("/dev/cpu_dma_latency", O_RDWR); if (fd < 0) { err_msg("Error opening /dev/cpu_dma_latency\n"); return -1; } retval = write(fd, &latency, 4); if (retval < 1) { err_msg("Error setting /dev/cpu_dma_latency\n"); close(fd); return -1; } debug_msg("Set /dev/cpu_dma_latency to %d\n", latency); return fd;}
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira <bristot@kernel.org>
*/
#include <proc/readproc.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <sched.h>
#include <stdio.h>
#include "utils.h"
#define MAX_MSG_LENGTH 1024
int config_debug;
/*
* err_msg - print an error message to the stderr
*/
void err_msg(const char *fmt, ...)
{
char message[MAX_MSG_LENGTH];
va_list ap;
va_start(ap, fmt);
vsnprintf(message, sizeof(message), fmt, ap);
va_end(ap);
fprintf(stderr, "%s", message);
}
/*
* debug_msg - print a debug message to stderr if debug is set
*/
void debug_msg(const char *fmt, ...)
{
char message[MAX_MSG_LENGTH];
va_list ap;
if (!config_debug)
return;
va_start(ap, fmt);
vsnprintf(message, sizeof(message), fmt, ap);
va_end(ap);
fprintf(stderr, "%s", message);
}
/*
* get_llong_from_str - get a long long int from a string
*/
long long get_llong_from_str(char *start)
{
long long value;
char *end;
errno = 0;
value = strtoll(start, &end, 10);
if (errno || start == end)
return -1;
return value;
}
/*
* get_duration - fill output with a human readable duration since start_time
*/
void get_duration(time_t start_time, char *output, int output_size)
{
time_t now = time(NULL);
struct tm *tm_info;
time_t duration;
duration = difftime(now, start_time);
tm_info = gmtime(&duration);
snprintf(output, output_size, "%3d %02d:%02d:%02d",
tm_info->tm_yday,
tm_info->tm_hour,
tm_info->tm_min,
tm_info->tm_sec);
}
/*
* parse_cpu_list - parse a cpu_list filling a char vector with cpus set
*
* Receives a cpu list, like 1-3,5 (cpus 1, 2, 3, 5), and then set the char
* in the monitored_cpus.
*
* XXX: convert to a bitmask.
*/
int parse_cpu_list(char *cpu_list, char **monitored_cpus)
{
char *mon_cpus;
const char *p;
int end_cpu;
int nr_cpus;
int cpu;
int i;
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
mon_cpus = malloc(nr_cpus * sizeof(char));
memset(mon_cpus, 0, (nr_cpus * sizeof(char)));
for (p = cpu_list; *p; ) {
cpu = atoi(p);
if (cpu < 0 || (!cpu && *p != '0') || cpu >= nr_cpus)
goto err;
while (isdigit(*p))
p++;
if (*p == '-') {
p++;
end_cpu = atoi(p);
if (end_cpu < cpu || (!end_cpu && *p != '0') || end_cpu >= nr_cpus)
goto err;
while (isdigit(*p))
p++;
} else
end_cpu = cpu;
if (cpu == end_cpu) {
debug_msg("cpu_list: adding cpu %d\n", cpu);
mon_cpus[cpu] = 1;
} else {
for (i = cpu; i <= end_cpu; i++) {
debug_msg("cpu_list: adding cpu %d\n", i);
mon_cpus[i] = 1;
}
}
if (*p == ',')
p++;
}
*monitored_cpus = mon_cpus;
return 0;
err:
debug_msg("Error parsing the cpu list %s", cpu_list);
return 1;
}
/*
* parse_duration - parse duration with s/m/h/d suffix converting it to seconds
*/
long parse_seconds_duration(char *val)
{
char *end;
long t;
t = strtol(val, &end, 10);
if (end) {
switch (*end) {
case 's':
case 'S':
break;
case 'm':
case 'M':
t *= 60;
break;
case 'h':
case 'H':
t *= 60 * 60;
break;
case 'd':
case 'D':
t *= 24 * 60 * 60;
break;
}
}
return t;
}
/*
* parse_ns_duration - parse duration with ns/us/ms/s converting it to nanoseconds
*/
long parse_ns_duration(char *val)
{
char *end;
long t;
t = strtol(val, &end, 10);
if (end) {
if (!strncmp(end, "ns", 2)) {
return t;
} else if (!strncmp(end, "us", 2)) {
t *= 1000;
return t;
} else if (!strncmp(end, "ms", 2)) {
t *= 1000 * 1000;
return t;
} else if (!strncmp(end, "s", 1)) {
t *= 1000 * 1000 * 1000;
return t;
}
return -1;
}
return t;
}
/*
* This is a set of helper functions to use SCHED_DEADLINE.
*/
#ifdef __x86_64__
# define __NR_sched_setattr 314
# define __NR_sched_getattr 315
#elif __i386__
# define __NR_sched_setattr 351
# define __NR_sched_getattr 352
#elif __arm__
# define __NR_sched_setattr 380
# define __NR_sched_getattr 381
#elif __aarch64__
# define __NR_sched_setattr 274
# define __NR_sched_getattr 275
#elif __powerpc__
# define __NR_sched_setattr 355
# define __NR_sched_getattr 356
#elif __s390x__
# define __NR_sched_setattr 345
# define __NR_sched_getattr 346
#endif
#define SCHED_DEADLINE 6
static inline int sched_setattr(pid_t pid, const struct sched_attr *attr,
unsigned int flags) {
return syscall(__NR_sched_setattr, pid, attr, flags);
}
static inline int sched_getattr(pid_t pid, struct sched_attr *attr,
unsigned int size, unsigned int flags)
{
return syscall(__NR_sched_getattr, pid, attr, size, flags);
}
int __set_sched_attr(int pid, struct sched_attr *attr)
{
int flags = 0;
int retval;
retval = sched_setattr(pid, attr, flags);
if (retval < 0) {
err_msg("boost_with_deadline failed to boost pid %d: %s\n",
pid, strerror(errno));
return 1;
}
return 0;
}
/*
* set_comm_sched_attr - set sched params to threads starting with char *comm
*
* This function uses procps to list the currently running threads and then
* set the sched_attr *attr to the threads that start with char *comm. It is
* mainly used to set the priority to the kernel threads created by the
* tracers.
*/
int set_comm_sched_attr(const char *comm, struct sched_attr *attr)
{
int flags = PROC_FILLCOM | PROC_FILLSTAT;
PROCTAB *ptp;
proc_t task;
int retval;
ptp = openproc(flags);
if (!ptp) {
err_msg("error openproc()\n");
return -ENOENT;
}
memset(&task, 0, sizeof(task));
while (readproc(ptp, &task)) {
retval = strncmp(comm, task.cmd, strlen(comm));
if (retval)
continue;
retval = __set_sched_attr(task.tid, attr);
if (retval)
goto out_err;
}
closeproc(ptp);
return 0;
out_err:
closeproc(ptp);
return 1;
}
#define INVALID_VAL (~0L)
static long get_long_ns_after_colon(char *start)
{
long val = INVALID_VAL;
/* find the ":" */
start = strstr(start, ":");
if (!start)
return -1;
/* skip ":" */
start++;
val = parse_ns_duration(start);
return val;
}
static long get_long_after_colon(char *start)
{
long val = INVALID_VAL;
/* find the ":" */
start = strstr(start, ":");
if (!start)
return -1;
/* skip ":" */
start++;
val = get_llong_from_str(start);
return val;
}
/*
* parse priority in the format:
* SCHED_OTHER:
* o:<prio>
* O:<prio>
* SCHED_RR:
* r:<prio>
* R:<prio>
* SCHED_FIFO:
* f:<prio>
* F:<prio>
* SCHED_DEADLINE:
* d:runtime:period
* D:runtime:period
*/
int parse_prio(char *arg, struct sched_attr *sched_param)
{
long prio;
long runtime;
long period;
memset(sched_param, 0, sizeof(*sched_param));
sched_param->size = sizeof(*sched_param);
switch (arg[0]) {
case 'd':
case 'D':
/* d:runtime:period */
if (strlen(arg) < 4)
return -1;
runtime = get_long_ns_after_colon(arg);
if (runtime == INVALID_VAL)
return -1;
period = get_long_ns_after_colon(&arg[2]);
if (period == INVALID_VAL)
return -1;
if (runtime > period)
return -1;
sched_param->sched_policy = SCHED_DEADLINE;
sched_param->sched_runtime = runtime;
sched_param->sched_deadline = period;
sched_param->sched_period = period;
break;
case 'f':
case 'F':
/* f:prio */
prio = get_long_after_colon(arg);
if (prio == INVALID_VAL)
return -1;
if (prio < sched_get_priority_min(SCHED_FIFO))
return -1;
if (prio > sched_get_priority_max(SCHED_FIFO))
return -1;
sched_param->sched_policy = SCHED_FIFO;
sched_param->sched_priority = prio;
break;
case 'r':
case 'R':
/* r:prio */
prio = get_long_after_colon(arg);
if (prio == INVALID_VAL)
return -1;
if (prio < sched_get_priority_min(SCHED_RR))
return -1;
if (prio > sched_get_priority_max(SCHED_RR))
return -1;
sched_param->sched_policy = SCHED_RR;
sched_param->sched_priority = prio;
break;
case 'o':
case 'O':
/* o:prio */
prio = get_long_after_colon(arg);
if (prio == INVALID_VAL)
return -1;
if (prio < sched_get_priority_min(SCHED_OTHER))
return -1;
if (prio > sched_get_priority_max(SCHED_OTHER))
return -1;
sched_param->sched_policy = SCHED_OTHER;
sched_param->sched_priority = prio;
break;
default:
return -1;
}
return 0;
}
/*
* set_cpu_dma_latency - set the /dev/cpu_dma_latecy
*
* This is used to reduce the exit from idle latency. The value
* will be reset once the file descriptor of /dev/cpu_dma_latecy
* is closed.
*
* Return: the /dev/cpu_dma_latecy file descriptor
*/
int set_cpu_dma_latency(int32_t latency)
{
int retval;
int fd;
fd = open("/dev/cpu_dma_latency", O_RDWR);
if (fd < 0) {
err_msg("Error opening /dev/cpu_dma_latency\n");
return -1;
}
retval = write(fd, &latency, 4);
if (retval < 1) {
err_msg("Error setting /dev/cpu_dma_latency\n");
close(fd);
return -1;
}
debug_msg("Set /dev/cpu_dma_latency to %d\n", latency);
return fd;
}