lxc/0134-lxc-do-cpuset-same-as-runc.patch

From 1118dbb609b83fcca6871e17a11de0752ef3f9d7 Mon Sep 17 00:00:00 2001
From: LiFeng <lifeng68@huawei.com>
Date: Wed, 18 Dec 2019 22:37:08 -0500
Subject: [PATCH 134/138] lxc: do cpuset same as runc

Signed-off-by: LiFeng <lifeng68@huawei.com>
---
 src/lxc/cgroups/cgfsng.c | 288 +----------------------------------------------
 1 file changed, 3 insertions(+), 285 deletions(-)

diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index 5908c31..79fc5d3 100644
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -248,288 +248,6 @@ static char *read_file(const char *fnam)
 	return buf;
 }
 
-/* Taken over modified from the kernel sources. */
-#define NBITS 32 /* bits in uint32_t */
-#define DIV_ROUND_UP(n, d) (((n) + (d)-1) / (d))
-#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, NBITS)
-
-static void set_bit(unsigned bit, uint32_t *bitarr)
-{
-	bitarr[bit / NBITS] |= (1 << (bit % NBITS));
-}
-
-static void clear_bit(unsigned bit, uint32_t *bitarr)
-{
-	bitarr[bit / NBITS] &= ~(1 << (bit % NBITS));
-}
-
-static bool is_set(unsigned bit, uint32_t *bitarr)
-{
-	return (bitarr[bit / NBITS] & (1 << (bit % NBITS))) != 0;
-}
-
-/* Create cpumask from cpulist aka turn:
- *
- *	0,2-3
- *
- * into bit array
- *
- *	1 0 1 1
- */
-static uint32_t *lxc_cpumask(char *buf, size_t nbits)
-{
-	char *token;
-	size_t arrlen;
-	uint32_t *bitarr;
-
-	arrlen = BITS_TO_LONGS(nbits);
-	bitarr = calloc(arrlen, sizeof(uint32_t));
-	if (!bitarr)
-		return NULL;
-
-	lxc_iterate_parts(token, buf, ",") {
-		errno = 0;
-		unsigned end, start;
-		char *range;
-
-		start = strtoul(token, NULL, 0);
-		end = start;
-		range = strchr(token, '-');
-		if (range)
-			end = strtoul(range + 1, NULL, 0);
-
-		if (!(start <= end)) {
-			free(bitarr);
-			return NULL;
-		}
-
-		if (end >= nbits) {
-			free(bitarr);
-			return NULL;
-		}
-
-		while (start <= end)
-			set_bit(start++, bitarr);
-	}
-
-	return bitarr;
-}
-
-/* Turn cpumask into simple, comma-separated cpulist. */
-static char *lxc_cpumask_to_cpulist(uint32_t *bitarr, size_t nbits)
-{
-	int ret;
-	size_t i;
-	char **cpulist = NULL;
-	char numstr[INTTYPE_TO_STRLEN(size_t)] = {0};
-
-	for (i = 0; i <= nbits; i++) {
-		if (!is_set(i, bitarr))
-			continue;
-
-		ret = snprintf(numstr, sizeof(numstr), "%zu", i);
-		if (ret < 0 || (size_t)ret >= sizeof(numstr)) {
-			lxc_free_array((void **)cpulist, free);
-			return NULL;
-		}
-
-		ret = lxc_append_string(&cpulist, numstr);
-		if (ret < 0) {
-			lxc_free_array((void **)cpulist, free);
-			return NULL;
-		}
-	}
-
-	if (!cpulist)
-		return NULL;
-
-	return lxc_string_join(",", (const char **)cpulist, false);
-}
-
-static ssize_t get_max_cpus(char *cpulist)
-{
-	char *c1, *c2;
-	char *maxcpus = cpulist;
-	size_t cpus = 0;
-
-	c1 = strrchr(maxcpus, ',');
-	if (c1)
-		c1++;
-
-	c2 = strrchr(maxcpus, '-');
-	if (c2)
-		c2++;
-
-	if (!c1 && !c2)
-		c1 = maxcpus;
-	else if (c1 > c2)
-		c2 = c1;
-	else if (c1 < c2)
-		c1 = c2;
-	else if (!c1 && c2)
-		c1 = c2;
-
-	errno = 0;
-	cpus = strtoul(c1, NULL, 0);
-	if (errno != 0)
-		return -1;
-
-	return cpus;
-}
-
-#define __ISOL_CPUS "/sys/devices/system/cpu/isolated"
-static bool cg_legacy_filter_and_set_cpus(char *path, bool am_initialized)
-{
-	int ret;
-	ssize_t i;
-	char *lastslash, *fpath, oldv;
-	ssize_t maxisol = 0, maxposs = 0;
-	char *cpulist = NULL, *isolcpus = NULL, *posscpus = NULL;
-	uint32_t *isolmask = NULL, *possmask = NULL;
-	bool bret = false, flipped_bit = false;
-	bool need_read_parent = false;
-
-	fpath = must_make_path(path, "cpuset.cpus", NULL);
-	posscpus = read_file(fpath);
-	if (!posscpus) {
-		SYSERROR("Failed to read file \"%s\"", fpath);
-		goto on_error;
-	}
-
-	if (strcmp(posscpus, "\n") == 0) {
-		need_read_parent = true;
-		free(fpath);
-		free(posscpus);
-		lastslash = strrchr(path, '/');
-		if (!lastslash) {
-			ERROR("Failed to detect \"/\" in \"%s\"", path);
-			return bret;
-		}
-		oldv = *lastslash;
-		*lastslash = '\0';
-		fpath = must_make_path(path, "cpuset.cpus", NULL);
-		posscpus = read_file(fpath);
-		if (!posscpus) {
-			SYSERROR("Failed to read file \"%s\"", fpath);
-			goto on_error;
-		}
-	}
-
-	/* Get maximum number of cpus found in possible cpuset. */
-	maxposs = get_max_cpus(posscpus);
-	if (maxposs < 0 || maxposs >= INT_MAX - 1)
-		goto on_error;
-
-	if (!file_exists(__ISOL_CPUS)) {
-		/* This system doesn't expose isolated cpus. */
-		DEBUG("The path \""__ISOL_CPUS"\" to read isolated cpus from does not exist");
-		cpulist = posscpus;
-		/* No isolated cpus but we weren't already initialized by
-		 * someone. We should simply copy the parents cpuset.cpus
-		 * values.
-		 */
-		if (!am_initialized) {
-			DEBUG("Copying cpu settings of parent cgroup");
-			goto copy_parent;
-		}
-		/* No isolated cpus but we were already initialized by someone.
-		 * Nothing more to do for us.
-		 */
-		goto on_success;
-	}
-
-	isolcpus = read_file(__ISOL_CPUS);
-	if (!isolcpus) {
-		SYSERROR("Failed to read file \""__ISOL_CPUS"\"");
-		goto on_error;
-	}
-	if (!isdigit(isolcpus[0])) {
-		TRACE("No isolated cpus detected");
-		cpulist = posscpus;
-		/* No isolated cpus but we weren't already initialized by
-		 * someone. We should simply copy the parents cpuset.cpus
-		 * values.
-		 */
-		if (!am_initialized) {
-			DEBUG("Copying cpu settings of parent cgroup");
-			goto copy_parent;
-		}
-		/* No isolated cpus but we were already initialized by someone.
-		 * Nothing more to do for us.
-		 */
-		goto on_success;
-	}
-
-	/* Get maximum number of cpus found in isolated cpuset. */
-	maxisol = get_max_cpus(isolcpus);
-	if (maxisol < 0 || maxisol >= INT_MAX - 1)
-		goto on_error;
-
-	if (maxposs < maxisol)
-		maxposs = maxisol;
-	maxposs++;
-
-	possmask = lxc_cpumask(posscpus, maxposs);
-	if (!possmask) {
-		ERROR("Failed to create cpumask for possible cpus");
-		goto on_error;
-	}
-
-	isolmask = lxc_cpumask(isolcpus, maxposs);
-	if (!isolmask) {
-		ERROR("Failed to create cpumask for isolated cpus");
-		goto on_error;
-	}
-
-	for (i = 0; i <= maxposs; i++) {
-		if (!is_set(i, isolmask) || !is_set(i, possmask))
-			continue;
-
-		flipped_bit = true;
-		clear_bit(i, possmask);
-	}
-
-	if (!flipped_bit) {
-		DEBUG("No isolated cpus present in cpuset");
-		goto on_success;
-	}
-	DEBUG("Removed isolated cpus from cpuset");
-
-	cpulist = lxc_cpumask_to_cpulist(possmask, maxposs);
-	if (!cpulist) {
-		ERROR("Failed to create cpu list");
-		goto on_error;
-	}
-
-copy_parent:
-	if (need_read_parent) {
-		*lastslash = oldv;
-	}
-	free(fpath);
-	fpath = must_make_path(path, "cpuset.cpus", NULL);
-	ret = lxc_write_to_file(fpath, cpulist, strlen(cpulist), false, 0666);
-	if (ret < 0) {
-		SYSERROR("Failed to write cpu list to \"%s\"", fpath);
-		goto on_error;
-	}
-
-on_success:
-	bret = true;
-
-on_error:
-	free(fpath);
-
-	free(isolcpus);
-	free(isolmask);
-
-	if (posscpus != cpulist)
-		free(posscpus);
-	free(possmask);
-
-	free(cpulist);
-	return bret;
-}
-
 /* Copy contents of parent(@path)/@file to @path/@file */
 static bool copy_parent_file(char *path, char *file)
 {
@@ -603,9 +321,9 @@ static bool build_sub_cpuset_cgroup_dir(char *cgpath)
 		}
 	}
 
-	/* Make sure any isolated cpus are removed from cpuset.cpus. */
-	if (!cg_legacy_filter_and_set_cpus(cgpath, false)) {
-		SYSERROR("Failed to remove isolated cpus");
+	/* copy parent's settings */
+	if (!copy_parent_file(cgpath, "cpuset.cpus")) {
+		SYSERROR("Failed to copy \"cpuset.cpus\" settings");
 		return false;
 	}
 
-- 
1.8.3.1