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-rw-r--r--miscutils/taskset.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/miscutils/taskset.c b/miscutils/taskset.c
new file mode 100644
index 0000000..4496aa5
--- /dev/null
+++ b/miscutils/taskset.c
@@ -0,0 +1,96 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * taskset - retrieve or set a processes' CPU affinity
+ * Copyright (c) 2006 Bernhard Fischer
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include "busybox.h"
+#include <sched.h>
+#include <unistd.h>
+#include <getopt.h> /* optind */
+
+#if ENABLE_FEATURE_TASKSET_FANCY
+#define TASKSET_PRINTF_MASK "%s"
+#define from_cpuset(x) __from_cpuset(&x)
+/* craft a string from the mask */
+static char *__from_cpuset(cpu_set_t *mask) {
+ int i;
+ char *ret = 0, *str = xzalloc(9);
+
+ for (i = CPU_SETSIZE - 4; i >= 0; i -= 4) {
+ char val = 0;
+ int off;
+ for (off = 0; off <= 3; ++off)
+ if (CPU_ISSET(i+off, mask))
+ val |= 1<<off;
+
+ if (!ret && val)
+ ret = str;
+ *str++ = (val-'0'<=9) ? (val+48) : (val+87);
+ }
+ return ret;
+}
+#else
+#define TASKSET_PRINTF_MASK "%x"
+#define from_cpuset(mask) mask
+#endif
+
+#define TASKSET_OPT_p (1)
+
+int taskset_main(int argc, char** argv)
+{
+ cpu_set_t mask, new_mask;
+ pid_t pid = 0;
+ unsigned long ul;
+ const char *state = "current\0new";
+ char *p_opt = NULL, *aff = NULL;
+
+ ul = getopt32(argc, argv, "+p:", &p_opt);
+
+ if (ul & TASKSET_OPT_p) {
+ if (argc == optind+1) { /* -p <aff> <pid> */
+ aff = p_opt;
+ p_opt = argv[optind];
+ }
+ argv += optind; /* me -p <arg> */
+ pid = xatoul_range(p_opt, 1, ULONG_MAX); /* -p <pid> */
+ } else
+ aff = *++argv; /* <aff> <cmd...> */
+ if (aff) {
+ unsigned i = 0;
+ unsigned long l = xstrtol_range(aff, 16, 1, ULONG_MAX);
+
+ CPU_ZERO(&new_mask);
+ while (i < CPU_SETSIZE && l >= (1<<i)) {
+ if ((1<<i) & l)
+ CPU_SET(i, &new_mask);
+ ++i;
+ }
+ }
+
+ if (ul & TASKSET_OPT_p) {
+print_aff:
+ if (sched_getaffinity(pid, sizeof (mask), &mask) < 0)
+ bb_perror_msg_and_die("Failed to %cet pid %d's affinity", 'g', pid);
+ printf("pid %d's %s affinity mask: "TASKSET_PRINTF_MASK"\n",
+ pid, state, from_cpuset(mask));
+ if (!*argv) /* no new affinity given or we did print already, done. */
+ return EXIT_SUCCESS;
+ }
+
+ if (sched_setaffinity(pid, sizeof (new_mask), &new_mask))
+ bb_perror_msg_and_die("Failed to %cet pid %d's affinity", 's', pid);
+ if (ul & TASKSET_OPT_p) {
+ state += 8;
+ ++argv;
+ goto print_aff;
+ }
+ ++argv;
+ execvp(*argv, argv);
+ bb_perror_msg_and_die("%s", *argv);
+}
+#undef TASKSET_OPT_p
+#undef TASKSET_PRINTF_MASK
+#undef from_cpuset