Commit 6ce1560d authored by James Morse's avatar James Morse Committed by Borislav Petkov
Browse files

x86/resctrl: Switch over to the resctrl mbps_val list 



Updates to resctrl's software controller follow the same path as
other configuration updates, but they don't modify the hardware state.
rdtgroup_schemata_write() uses parse_line() and the resource's
parse_ctrlval() function to stage the configuration.
resctrl_arch_update_domains() then updates the mbps_val[] array
instead, and resctrl_arch_update_domains() skips the rdt_ctrl_update()
call that would update hardware.

This complicates the interface between resctrl's filesystem parts
and architecture specific code. It should be possible for mba_sc
to be completely implemented by the filesystem parts of resctrl. This
would allow it to work on a second architecture with no additional code.
resctrl_arch_update_domains() using the mbps_val[] array prevents this.

Change parse_bw() to write the configuration value directly to the
mbps_val[] array in the domain structure. Change rdtgroup_schemata_write()
to skip the call to resctrl_arch_update_domains(), meaning all the
mba_sc specific code in resctrl_arch_update_domains() can be removed.
On the read-side, show_doms() and update_mba_bw() are changed to read
the mbps_val[] array from the domain structure. With this,
resctrl_arch_get_config() no longer needs to consider mba_sc resources.

Signed-off-by: default avatarJames Morse <james.morse@arm.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Reviewed-by: default avatarJamie Iles <quic_jiles@quicinc.com>
Reviewed-by: default avatarShaopeng Tan <tan.shaopeng@fujitsu.com>
Reviewed-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Tested-by: default avatarXin Hao <xhao@linux.alibaba.com>
Tested-by: default avatarShaopeng Tan <tan.shaopeng@fujitsu.com>
Tested-by: default avatarCristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20220902154829.30399-10-james.morse@arm.com
parent 781096d9

arch/x86/kernel/cpu/resctrl/ctrlmondata.c

+27 −17
Original line number Original line Diff line number Diff line
@@ -61,6 +61,7 @@ int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s, 
	     struct rdt_domain *d)

	     struct rdt_domain *d)

{

{

	struct resctrl_staged_config *cfg;

	struct resctrl_staged_config *cfg;

	u32 closid = data->rdtgrp->closid;

	struct rdt_resource *r = s->res;

	struct rdt_resource *r = s->res;

	unsigned long bw_val;

	unsigned long bw_val;
@@ -72,6 +73,12 @@ int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s, 




	if (!bw_validate(data->buf, &bw_val, r))

	if (!bw_validate(data->buf, &bw_val, r))

		return -EINVAL;

		return -EINVAL;



	if (is_mba_sc(r)) {

		d->mbps_val[closid] = bw_val;

		return 0;

	}



	cfg->new_ctrl = bw_val;

	cfg->new_ctrl = bw_val;

	cfg->have_new_ctrl = true;

	cfg->have_new_ctrl = true;
@@ -261,14 +268,13 @@ static u32 get_config_index(u32 closid, enum resctrl_conf_type type) 




static bool apply_config(struct rdt_hw_domain *hw_dom,

static bool apply_config(struct rdt_hw_domain *hw_dom,

			 struct resctrl_staged_config *cfg, u32 idx,

			 struct resctrl_staged_config *cfg, u32 idx,

			 cpumask_var_t cpu_mask, bool mba_sc)

			 cpumask_var_t cpu_mask)

{

{

	struct rdt_domain *dom = &hw_dom->d_resctrl;

	struct rdt_domain *dom = &hw_dom->d_resctrl;

	u32 *dc = !mba_sc ? hw_dom->ctrl_val : hw_dom->mbps_val;





	if (cfg->new_ctrl != dc[idx]) {

	if (cfg->new_ctrl != hw_dom->ctrl_val[idx]) {

		cpumask_set_cpu(cpumask_any(&dom->cpu_mask), cpu_mask);

		cpumask_set_cpu(cpumask_any(&dom->cpu_mask), cpu_mask);

		dc[idx] = cfg->new_ctrl;

		hw_dom->ctrl_val[idx] = cfg->new_ctrl;





		return true;

		return true;

	}

	}
@@ -284,14 +290,12 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid) 
	enum resctrl_conf_type t;

	enum resctrl_conf_type t;

	cpumask_var_t cpu_mask;

	cpumask_var_t cpu_mask;

	struct rdt_domain *d;

	struct rdt_domain *d;

	bool mba_sc;

	int cpu;

	int cpu;

	u32 idx;

	u32 idx;





	if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))

	if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))

		return -ENOMEM;

		return -ENOMEM;





	mba_sc = is_mba_sc(r);

	msr_param.res = NULL;

	msr_param.res = NULL;

	list_for_each_entry(d, &r->domains, list) {

	list_for_each_entry(d, &r->domains, list) {

		hw_dom = resctrl_to_arch_dom(d);

		hw_dom = resctrl_to_arch_dom(d);
@@ -301,7 +305,7 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid) 
				continue;

				continue;





			idx = get_config_index(closid, t);

			idx = get_config_index(closid, t);

			if (!apply_config(hw_dom, cfg, idx, cpu_mask, mba_sc))

			if (!apply_config(hw_dom, cfg, idx, cpu_mask))

				continue;

				continue;





			if (!msr_param.res) {

			if (!msr_param.res) {
@@ -315,11 +319,7 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid) 
		}

		}

	}

	}





	/*

	if (cpumask_empty(cpu_mask))

	 * Avoid writing the control msr with control values when

	 * MBA software controller is enabled

	 */

	if (cpumask_empty(cpu_mask) || mba_sc)

		goto done;

		goto done;

	cpu = get_cpu();

	cpu = get_cpu();

	/* Update resource control msr on this CPU if it's in cpu_mask. */

	/* Update resource control msr on this CPU if it's in cpu_mask. */
@@ -406,6 +406,14 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, 




	list_for_each_entry(s, &resctrl_schema_all, list) {

	list_for_each_entry(s, &resctrl_schema_all, list) {

		r = s->res;

		r = s->res;



		/*

		 * Writes to mba_sc resources update the software controller,

		 * not the control MSR.

		 */

		if (is_mba_sc(r))

			continue;



		ret = resctrl_arch_update_domains(r, rdtgrp->closid);

		ret = resctrl_arch_update_domains(r, rdtgrp->closid);

		if (ret)

		if (ret)

			goto out;

			goto out;
@@ -433,9 +441,7 @@ u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d, 
	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);

	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);

	u32 idx = get_config_index(closid, type);

	u32 idx = get_config_index(closid, type);





	if (!is_mba_sc(r))

	return hw_dom->ctrl_val[idx];

	return hw_dom->ctrl_val[idx];

	return hw_dom->mbps_val[idx];

}

}





static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int closid)

static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int closid)
@@ -450,8 +456,12 @@ static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int clo 
		if (sep)

		if (sep)

			seq_puts(s, ";");

			seq_puts(s, ";");





		if (is_mba_sc(r))

			ctrl_val = dom->mbps_val[closid];

		else

			ctrl_val = resctrl_arch_get_config(r, dom, closid,

			ctrl_val = resctrl_arch_get_config(r, dom, closid,

							   schema->conf_type);

							   schema->conf_type);



		seq_printf(s, r->format_str, dom->id, max_data_width,

		seq_printf(s, r->format_str, dom->id, max_data_width,

			   ctrl_val);

			   ctrl_val);

		sep = true;

		sep = true;

arch/x86/kernel/cpu/resctrl/monitor.c

+4 −6
Original line number Original line Diff line number Diff line
@@ -447,13 +447,11 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm) 
	hw_dom_mba = resctrl_to_arch_dom(dom_mba);

	hw_dom_mba = resctrl_to_arch_dom(dom_mba);





	cur_bw = pmbm_data->prev_bw;

	cur_bw = pmbm_data->prev_bw;

	user_bw = resctrl_arch_get_config(r_mba, dom_mba, closid, CDP_NONE);

	user_bw = dom_mba->mbps_val[closid];

	delta_bw = pmbm_data->delta_bw;

	delta_bw = pmbm_data->delta_bw;

	/*



	 * resctrl_arch_get_config() chooses the mbps/ctrl value to return

	/* MBA resource doesn't support CDP */

	 * based on is_mba_sc(). For now, reach into the hw_dom.

	cur_msr_val = resctrl_arch_get_config(r_mba, dom_mba, closid, CDP_NONE);

	 */

	cur_msr_val = hw_dom_mba->ctrl_val[closid];





	/*

	/*

	 * For Ctrl groups read data from child monitor groups.

	 * For Ctrl groups read data from child monitor groups.

arch/x86/kernel/cpu/resctrl/rdtgroup.c

+21 −6
Original line number Original line Diff line number Diff line
@@ -1356,11 +1356,13 @@ static int rdtgroup_size_show(struct kernfs_open_file *of, 
			      struct seq_file *s, void *v)

			      struct seq_file *s, void *v)

{

{

	struct resctrl_schema *schema;

	struct resctrl_schema *schema;

	enum resctrl_conf_type type;

	struct rdtgroup *rdtgrp;

	struct rdtgroup *rdtgrp;

	struct rdt_resource *r;

	struct rdt_resource *r;

	struct rdt_domain *d;

	struct rdt_domain *d;

	unsigned int size;

	unsigned int size;

	int ret = 0;

	int ret = 0;

	u32 closid;

	bool sep;

	bool sep;

	u32 ctrl;

	u32 ctrl;
@@ -1386,8 +1388,11 @@ static int rdtgroup_size_show(struct kernfs_open_file *of, 
		goto out;

		goto out;

	}

	}





	closid = rdtgrp->closid;



	list_for_each_entry(schema, &resctrl_schema_all, list) {

	list_for_each_entry(schema, &resctrl_schema_all, list) {

		r = schema->res;

		r = schema->res;

		type = schema->conf_type;

		sep = false;

		sep = false;

		seq_printf(s, "%*s:", max_name_width, schema->name);

		seq_printf(s, "%*s:", max_name_width, schema->name);

		list_for_each_entry(d, &r->domains, list) {

		list_for_each_entry(d, &r->domains, list) {
@@ -1396,9 +1401,12 @@ static int rdtgroup_size_show(struct kernfs_open_file *of, 
			if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {

			if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {

				size = 0;

				size = 0;

			} else {

			} else {

				if (is_mba_sc(r))

					ctrl = d->mbps_val[closid];

				else

					ctrl = resctrl_arch_get_config(r, d,

					ctrl = resctrl_arch_get_config(r, d,

							       rdtgrp->closid,

								       closid,

							       schema->conf_type);

								       type);

				if (r->rid == RDT_RESOURCE_MBA)

				if (r->rid == RDT_RESOURCE_MBA)

					size = ctrl;

					size = ctrl;

				else

				else
@@ -2818,14 +2826,19 @@ static int rdtgroup_init_cat(struct resctrl_schema *s, u32 closid) 
}

}





/* Initialize MBA resource with default values. */

/* Initialize MBA resource with default values. */

static void rdtgroup_init_mba(struct rdt_resource *r)

static void rdtgroup_init_mba(struct rdt_resource *r, u32 closid)

{

{

	struct resctrl_staged_config *cfg;

	struct resctrl_staged_config *cfg;

	struct rdt_domain *d;

	struct rdt_domain *d;





	list_for_each_entry(d, &r->domains, list) {

	list_for_each_entry(d, &r->domains, list) {

		if (is_mba_sc(r)) {

			d->mbps_val[closid] = MBA_MAX_MBPS;

			continue;

		}



		cfg = &d->staged_config[CDP_NONE];

		cfg = &d->staged_config[CDP_NONE];

		cfg->new_ctrl = is_mba_sc(r) ? MBA_MAX_MBPS : r->default_ctrl;

		cfg->new_ctrl = r->default_ctrl;

		cfg->have_new_ctrl = true;

		cfg->have_new_ctrl = true;

	}

	}

}

}
@@ -2840,7 +2853,9 @@ static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp) 
	list_for_each_entry(s, &resctrl_schema_all, list) {

	list_for_each_entry(s, &resctrl_schema_all, list) {

		r = s->res;

		r = s->res;

		if (r->rid == RDT_RESOURCE_MBA) {

		if (r->rid == RDT_RESOURCE_MBA) {

			rdtgroup_init_mba(r);

			rdtgroup_init_mba(r, rdtgrp->closid);

			if (is_mba_sc(r))

				continue;

		} else {

		} else {

			ret = rdtgroup_init_cat(s, rdtgrp->closid);

			ret = rdtgroup_init_cat(s, rdtgrp->closid);

			if (ret < 0)

			if (ret < 0)