← Commit list

162ac7f45

Denys Vlasenko

2019-11-01

SUCCESS Duration: 154s

Subject

taskset: add support for taking/printing CPU list (-c option)

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

util-linux/taskset.c +118 -11

util-linux/taskset.c+118 -11

@@ -20,6 +20,14 @@
	//config: Needed for machines with more than 32-64 CPUs:
	//config: affinity parameter 0xHHHHHHHHHHHHHHHHHHHH can be arbitrarily long
	//config: in this case. Otherwise, it is limited to sizeof(long).
+	//config:
+	//config:config FEATURE_TASKSET_CPULIST
+	//config: bool "CPU list support (-c option)"
+	//config: default y
+	//config: depends on FEATURE_TASKSET_FANCY
+	//config: help
+	//config: Add support for taking/printing affinity as CPU list when '-c'
+	//config: option is used. For example, it prints '0-3,7' instead of mask '8f'.

	//applet:IF_TASKSET(APPLET_NOEXEC(taskset, taskset, BB_DIR_USR_BIN, BB_SUID_DROP, taskset))

@@ -108,26 +116,109 @@ static unsigned long get_aff(int pid, unsigned sz)
	return mask;
	}

+	#if ENABLE_FEATURE_TASKSET_CPULIST
+	/*
+	* Parse the CPU list and set the mask accordingly.
+	*
+	* The list element can be either a CPU index or a range of CPU indices.
+	* Example: "1,3,5-7".
+	*
+	* note1: pattern specifiers after a range (e.g. 0-255:2/64) are not supported
+	* note2: leading/trailing white-spaces are not allowed
+	*/
+	static void parse_cpulist(ul mask, unsigned max, char s)
+	{
+	char *aff = s;
+	for (;;) {
+	unsigned bit, end;
+
+	bit = end = bb_strtou(s, &s, 10);
+	if (*s == '-') {
+	s++;
+	end = bb_strtou(s, &s, 10);
+	}
+	if ((s != ',' && s != '\0')
+	\|\| bit > end
+	\|\| end == UINT_MAX /* bb_strtou returns this on malformed / ERANGE numbers */
+	) {
+	bb_error_msg_and_die("bad affinity '%s'", aff);
+	}
+	while (bit <= end && bit < max) {
+	mask[bit / BITS_UL] \|= (1UL << (bit & MASK_UL));
+	bit++;
+	}
+	if (*s == '\0')
+	break;
+	s++;
+	}
+	}
+	static void print_cpulist(const ul *mask, unsigned mask_size_in_bytes)
+	{
+	const ul *mask_end;
+	const char *delim;
+	unsigned pos;
+	ul bit;
+
+	mask_end = mask + mask_size_in_bytes / sizeof(mask[0]);
+	delim = "";
+	pos = 0;
+	bit = 1;
+	for (;;) {
+	if (*mask & bit) {
+	unsigned onebit = pos + 1;
+	printf("%s%u", delim, pos);
+	do {
+	pos++;
+	bit <<= 1;
+	if (bit == 0) {
+	mask++;
+	if (mask >= mask_end)
+	break;
+	bit = 1;
+	}
+	} while (*mask & bit);
+	if (onebit != pos)
+	printf("-%u", pos - 1);
+	delim = ",";
+	}
+	pos++;
+	bit <<= 1;
+	if (bit == 0) {
+	mask++;
+	if (mask >= mask_end)
+	break;
+	bit = 1;
+	}
+	}
+	bb_putchar('\n');
+	}
+	#endif
+
	int taskset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
	int taskset_main(int argc UNUSED_PARAM, char **argv)
	{
	ul *mask;
	unsigned mask_size_in_bytes;
	pid_t pid = 0;
-	unsigned opt_p;
	const char *current_new;
	char *aff;
+	unsigned opts;
+	enum {
+	OPT_p = 1 << 0,
+	OPT_c = (1 << 1) * ENABLE_FEATURE_TASKSET_CPULIST,
+	};

	/* NB: we mimic util-linux's taskset: -p does not take
	* an argument, i.e., "-pN" is NOT valid, only "-p N"!
	* Indeed, util-linux-2.13-pre7 uses:
	* getopt_long(argc, argv, "+pchV", ...), not "...p:..." */

-	opt_p = getopt32(argv, "^+" "p" "\0" "-1" /* at least 1 arg */);
+	opts = getopt32(argv, "^+" "p"IF_FEATURE_TASKSET_CPULIST("c")
+	"\0" "-1" /* at least 1 arg */);
	argv += optind;

	aff = *argv++;
-	if (opt_p) {
+	if (opts & OPT_p) {
	char *pid_str = aff;
	if (argv) { / "-p <aff> <pid> ...rest.is.ignored..." */
	pid_str = argv; / NB: argv != NULL in this case /
@@ -144,8 +235,14 @@ int taskset_main(int argc UNUSED_PARAM, char **argv)
	current_new = "current";
	print_aff:
	mask = get_aff(pid, &mask_size_in_bytes);
-	if (opt_p) {
-	printf("pid %d's %s affinity mask: "TASKSET_PRINTF_MASK"\n",
+	if (opts & OPT_p) {
+	#if ENABLE_FEATURE_TASKSET_CPULIST
+	if (opts & OPT_c) {
+	printf("pid %d's %s affinity list: ", pid, current_new);
+	print_cpulist(mask, mask_size_in_bytes);
+	} else
+	#endif
+	printf("pid %d's %s affinity mask: "TASKSET_PRINTF_MASK"\n",
	pid, current_new, from_mask(mask, mask_size_in_bytes));
	if (*argv == NULL) {
	/* Either it was just "-p <pid>",
@@ -158,17 +255,27 @@ int taskset_main(int argc UNUSED_PARAM, char **argv)
	}
	memset(mask, 0, mask_size_in_bytes);

-	/* Affinity was specified, translate it into mask */
-	/* it is always in hex, skip "0x" if it exists */
-	if (aff[0] == '0' && (aff[1]\|0x20) == 'x')
-	aff += 2;
-
	if (!ENABLE_FEATURE_TASKSET_FANCY) {
+	/* Affinity was specified, translate it into mask */
+	/* it is always in hex, skip "0x" if it exists */
+	if (aff[0] == '0' && (aff[1]\|0x20) == 'x')
+	aff += 2;
	mask[0] = xstrtoul(aff, 16);
-	} else {
+	}
+	#if ENABLE_FEATURE_TASKSET_CPULIST
+	else if (opts & OPT_c) {
+	parse_cpulist(mask, mask_size_in_bytes * 8, aff);
+	}
+	#endif
+	else {
	unsigned i;
	char *last_char;

+	/* Affinity was specified, translate it into mask */
+	/* it is always in hex, skip "0x" if it exists */
+	if (aff[0] == '0' && (aff[1]\|0x20) == 'x')
+	aff += 2;
+
	i = 0; /* bit pos in mask[] */

	/* aff is ASCII hex string, accept very long masks in this form.