Commit 7cc17205 authored by Chen Ridong's avatar Chen Ridong Committed by Tejun Heo
Browse files

cpuset: remove v1-specific code from generate_sched_domains 



Following the introduction of cpuset1_generate_sched_domains() for v1
in the previous patch, v1-specific logic can now be removed from the
generic generate_sched_domains(). This patch cleans up the v1-only
code and ensures uf_node is only visible when CONFIG_CPUSETS_V1=y.

Signed-off-by: default avatarChen Ridong <chenridong@huawei.com>
Reviewed-by: default avatarWaiman Long <longman@redhat.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 6e1d31ce

kernel/cgroup/cpuset-internal.h

+3 −7
Original line number Diff line number Diff line
@@ -175,14 +175,14 @@ struct cpuset { 
	/* Handle for cpuset.cpus.partition */

	struct cgroup_file partition_file;



	/* Used to merge intersecting subsets for generate_sched_domains */

	struct uf_node node;



#ifdef CONFIG_CPUSETS_V1

	struct fmeter fmeter;		/* memory_pressure filter */



	/* for custom sched domain */

	int relax_domain_level;



	/* Used to merge intersecting subsets for generate_sched_domains */

	struct uf_node node;

#endif

};
@@ -314,8 +314,6 @@ void cpuset1_hotplug_update_tasks(struct cpuset *cs, 
int cpuset1_validate_change(struct cpuset *cur, struct cpuset *trial);

void cpuset1_init(struct cpuset *cs);

void cpuset1_online_css(struct cgroup_subsys_state *css);

void update_domain_attr_tree(struct sched_domain_attr *dattr,

				    struct cpuset *root_cs);

int cpuset1_generate_sched_domains(cpumask_var_t **domains,

			struct sched_domain_attr **attributes);
@@ -330,8 +328,6 @@ static inline int cpuset1_validate_change(struct cpuset *cur, 
				struct cpuset *trial) { return 0; }

static inline void cpuset1_init(struct cpuset *cs) {}

static inline void cpuset1_online_css(struct cgroup_subsys_state *css) {}

static inline void update_domain_attr_tree(struct sched_domain_attr *dattr,

				    struct cpuset *root_cs) {}

static inline int cpuset1_generate_sched_domains(cpumask_var_t **domains,

			struct sched_domain_attr **attributes) { return 0; };

kernel/cgroup/cpuset-v1.c

+1 −1
Original line number Diff line number Diff line
@@ -560,7 +560,7 @@ update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c) 
		dattr->relax_domain_level = c->relax_domain_level;

}



void update_domain_attr_tree(struct sched_domain_attr *dattr,

static void update_domain_attr_tree(struct sched_domain_attr *dattr,

				    struct cpuset *root_cs)

{

	struct cpuset *cp;

kernel/cgroup/cpuset.c

+24 −121
Original line number Diff line number Diff line
@@ -789,18 +789,13 @@ static int generate_sched_domains(cpumask_var_t **domains, 
{

	struct cpuset *cp;	/* top-down scan of cpusets */

	struct cpuset **csa;	/* array of all cpuset ptrs */

	int csn;		/* how many cpuset ptrs in csa so far */

	int i, j;		/* indices for partition finding loops */

	cpumask_var_t *doms;	/* resulting partition; i.e. sched domains */

	struct sched_domain_attr *dattr;  /* attributes for custom domains */

	int ndoms = 0;		/* number of sched domains in result */

	int nslot;		/* next empty doms[] struct cpumask slot */

	struct cgroup_subsys_state *pos_css;

	bool root_load_balance = is_sched_load_balance(&top_cpuset);

	bool cgrpv2 = cpuset_v2();

	int nslot_update;



	if (!cgrpv2)

	if (!cpuset_v2())

		return cpuset1_generate_sched_domains(domains, attributes);



	doms = NULL;
@@ -808,70 +803,26 @@ static int generate_sched_domains(cpumask_var_t **domains, 
	csa = NULL;



	/* Special case for the 99% of systems with one, full, sched domain */

	if (root_load_balance && cpumask_empty(subpartitions_cpus)) {

single_root_domain:

	if (cpumask_empty(subpartitions_cpus)) {

		ndoms = 1;

		doms = alloc_sched_domains(ndoms);

		if (!doms)

			goto done;



		dattr = kmalloc(sizeof(struct sched_domain_attr), GFP_KERNEL);

		if (dattr) {

			*dattr = SD_ATTR_INIT;

			update_domain_attr_tree(dattr, &top_cpuset);

		}

		cpumask_and(doms[0], top_cpuset.effective_cpus,

			    housekeeping_cpumask(HK_TYPE_DOMAIN));



		goto done;

		/* !csa will be checked and can be correctly handled */

		goto generate_doms;

	}



	csa = kmalloc_array(nr_cpusets(), sizeof(cp), GFP_KERNEL);

	if (!csa)

		goto done;

	csn = 0;



	/* Find how many partitions and cache them to csa[] */

	rcu_read_lock();

	if (root_load_balance)

		csa[csn++] = &top_cpuset;

	cpuset_for_each_descendant_pre(cp, pos_css, &top_cpuset) {

		if (cp == &top_cpuset)

			continue;



		if (cgrpv2)

			goto v2;



		/*

		 * v1:

		 * Continue traversing beyond @cp iff @cp has some CPUs and

		 * isn't load balancing.  The former is obvious.  The

		 * latter: All child cpusets contain a subset of the

		 * parent's cpus, so just skip them, and then we call

		 * update_domain_attr_tree() to calc relax_domain_level of

		 * the corresponding sched domain.

		 */

		if (!cpumask_empty(cp->cpus_allowed) &&

		    !(is_sched_load_balance(cp) &&

		      cpumask_intersects(cp->cpus_allowed,

					 housekeeping_cpumask(HK_TYPE_DOMAIN))))

			continue;



		if (is_sched_load_balance(cp) &&

		    !cpumask_empty(cp->effective_cpus))

			csa[csn++] = cp;



		/* skip @cp's subtree */

		pos_css = css_rightmost_descendant(pos_css);

		continue;



v2:

		/*

		 * Only valid partition roots that are not isolated and with

		 * non-empty effective_cpus will be saved into csn[].

		 * non-empty effective_cpus will be saved into csa[].

		 */

		if ((cp->partition_root_state == PRS_ROOT) &&

		    !cpumask_empty(cp->effective_cpus))

			csa[csn++] = cp;

			csa[ndoms++] = cp;



		/*

		 * Skip @cp's subtree if not a partition root and has no
@@ -882,40 +833,18 @@ static int generate_sched_domains(cpumask_var_t **domains, 
	}

	rcu_read_unlock();



	/*

	 * If there are only isolated partitions underneath the cgroup root,

	 * we can optimize out unneeded sched domains scanning.

	 */

	if (root_load_balance && (csn == 1))

		goto single_root_domain;



	for (i = 0; i < csn; i++)

		uf_node_init(&csa[i]->node);



	/* Merge overlapping cpusets */

	for (i = 0; i < csn; i++) {

		for (j = i + 1; j < csn; j++) {

			if (cpusets_overlap(csa[i], csa[j])) {

	for (i = 0; i < ndoms; i++) {

		for (j = i + 1; j < ndoms; j++) {

			if (cpusets_overlap(csa[i], csa[j]))

				/*

				 * Cgroup v2 shouldn't pass down overlapping

				 * partition root cpusets.

				 */

				WARN_ON_ONCE(cgrpv2);

				uf_union(&csa[i]->node, &csa[j]->node);

				WARN_ON_ONCE(1);

		}

	}

	}



	/* Count the total number of domains */

	for (i = 0; i < csn; i++) {

		if (uf_find(&csa[i]->node) == &csa[i]->node)

			ndoms++;

	}



	/*

	 * Now we know how many domains to create.

	 * Convert <csn, csa> to <ndoms, doms> and populate cpu masks.

	 */

generate_doms:

	doms = alloc_sched_domains(ndoms);

	if (!doms)

		goto done;
@@ -932,45 +861,19 @@ static int generate_sched_domains(cpumask_var_t **domains, 
	 * to SD_ATTR_INIT. Also non-isolating partition root CPUs are a

	 * subset of HK_TYPE_DOMAIN housekeeping CPUs.

	 */

	if (cgrpv2) {

	for (i = 0; i < ndoms; i++) {

		/*

		 * The top cpuset may contain some boot time isolated

		 * CPUs that need to be excluded from the sched domain.

		 */

			if (csa[i] == &top_cpuset)

				cpumask_and(doms[i], csa[i]->effective_cpus,

		if (!csa || csa[i] == &top_cpuset)

			cpumask_and(doms[i], top_cpuset.effective_cpus,

				    housekeeping_cpumask(HK_TYPE_DOMAIN));

		else

			cpumask_copy(doms[i], csa[i]->effective_cpus);

		if (dattr)

			dattr[i] = SD_ATTR_INIT;

	}

		goto done;

	}



	for (nslot = 0, i = 0; i < csn; i++) {

		nslot_update = 0;

		for (j = i; j < csn; j++) {

			if (uf_find(&csa[j]->node) == &csa[i]->node) {

				struct cpumask *dp = doms[nslot];



				if (i == j) {

					nslot_update = 1;

					cpumask_clear(dp);

					if (dattr)

						*(dattr + nslot) = SD_ATTR_INIT;

				}

				cpumask_or(dp, dp, csa[j]->effective_cpus);

				cpumask_and(dp, dp, housekeeping_cpumask(HK_TYPE_DOMAIN));

				if (dattr)

					update_domain_attr_tree(dattr + nslot, csa[j]);

			}

		}

		if (nslot_update)

			nslot++;

	}

	BUG_ON(nslot != ndoms);



done:

	kfree(csa);