/* Disk protection for HP/DELL machines. * * Copyright 2008 Eric Piel * Copyright 2009 Pavel Machek * Copyright 2012 Sonal Santan * Copyright 2014 Pali Rohár * * GPLv2. */ #include #include #include #include #include #include #include #include #include #include #include #include #include static int noled; static char unload_heads_path[64]; static char device_path[32]; static const char app_name[] = "FREE FALL"; static int set_unload_heads_path(char *device) { if (strlen(device) <= 5 || strncmp(device, "/dev/", 5) != 0) return -EINVAL; strncpy(device_path, device, sizeof(device_path) - 1); snprintf(unload_heads_path, sizeof(unload_heads_path) - 1, "/sys/block/%s/device/unload_heads", device+5); return 0; } static int valid_disk(void) { int fd = open(unload_heads_path, O_RDONLY); if (fd < 0) { perror(unload_heads_path); return 0; } close(fd); return 1; } static void write_int(char *path, int i) { char buf[1024]; int fd = open(path, O_RDWR); if (fd < 0) { perror("open"); exit(1); } sprintf(buf, "%d", i); if (write(fd, buf, strlen(buf)) != strlen(buf)) { perror("write"); exit(1); } close(fd); } static void set_led(int on) { if (noled) return; write_int("/sys/class/leds/hp::hddprotect/brightness", on); } static void protect(int seconds) { const char *str = (seconds == 0) ? "Unparked" : "Parked"; write_int(unload_heads_path, seconds*1000); syslog(LOG_INFO, "%s %s disk head\n", str, device_path); } static int on_ac(void) { /* /sys/class/power_supply/AC0/online */ return 1; } static int lid_open(void) { /* /proc/acpi/button/lid/LID/state */ return 1; } static void ignore_me(int signum) { protect(0); set_led(0); } int main(int argc, char **argv) { int fd, ret; struct stat st; struct sched_param param; if (argc == 1) ret = set_unload_heads_path("/dev/sda"); else if (argc == 2) ret = set_unload_heads_path(argv[1]); else ret = -EINVAL; if (ret || !valid_disk()) { fprintf(stderr, "usage: %s (default: /dev/sda)\n", argv[0]); exit(1); } fd = open("/dev/freefall", O_RDONLY); if (fd < 0) { perror("/dev/freefall"); return EXIT_FAILURE; } if (stat("/sys/class/leds/hp::hddprotect/brightness", &st)) noled = 1; if (daemon(0, 0) != 0) { perror("daemon"); return EXIT_FAILURE; } openlog(app_name, LOG_CONS | LOG_PID | LOG_NDELAY, LOG_LOCAL1); param.sched_priority = sched_get_priority_max(SCHED_FIFO); sched_setscheduler(0, SCHED_FIFO, ¶m); mlockall(MCL_CURRENT|MCL_FUTURE); signal(SIGALRM, ignore_me); for (;;) { unsigned char count; ret = read(fd, &count, sizeof(count)); alarm(0); if ((ret == -1) && (errno == EINTR)) { /* Alarm expired, time to unpark the heads */ continue; } if (ret != sizeof(count)) { perror("read"); break; } protect(21); set_led(1); if (1 || on_ac() || lid_open()) alarm(2); else alarm(20); } closelog(); close(fd); return EXIT_SUCCESS; } t.git/commit/tools/leds?h=nds-private-remove&id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>leds/.gitignore
diff options
context:
space:
mode:
authorSteven Rostedt (VMware) <rostedt@goodmis.org>2017-01-30 19:27:10 -0500
committerSteven Rostedt (VMware) <rostedt@goodmis.org>2017-01-31 09:13:49 -0500
commit79c6f448c8b79c321e4a1f31f98194e4f6b6cae7 (patch)
tree370efda701f03cccf21e02bb1fdd3b852547d75c /tools/leds/.gitignore
parent0c744ea4f77d72b3dcebb7a8f2684633ec79be88 (diff)
tracing: Fix hwlat kthread migration
The hwlat tracer creates a kernel thread at start of the tracer. It is pinned to a single CPU and will move to the next CPU after each period of running. If the user modifies the migration thread's affinity, it will not change after that happens. The original code created the thread at the first instance it was called, but later was changed to destroy the thread after the tracer was finished, and would not be created until the next instance of the tracer was established. The code that initialized the affinity was only called on the initial instantiation of the tracer. After that, it was not initialized, and the previous affinity did not match the current newly created one, making it appear that the user modified the thread's affinity when it did not, and the thread failed to migrate again. Cc: stable@vger.kernel.org Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'tools/leds/.gitignore')