Commit f07e9d02 authored by James Morse's avatar James Morse Committed by Borislav Petkov
Browse files

x86/resctrl: Add a helper to read a closid's configuration 



Functions like show_doms() reach into the architecture's private
structure to retrieve the configuration from the struct rdt_hw_resource.

The hardware configuration may look completely different to the
values resctrl gets from user-space. The staged configuration and
resctrl_arch_update_domains() allow the architecture to convert or
translate these values.

Resctrl shouldn't read or write the ctrl_val[] values directly. Add
a helper to read the current configuration. This will allow another
architecture to scale the bitmaps if necessary, and possibly use
controls that don't take the user-space control format at all.

Of the remaining functions that access ctrl_val[] directly,
apply_config() is part of the architecture-specific code, and is
called via resctrl_arch_update_domains(). reset_all_ctrls() will be an
architecture specific helper.

update_mba_bw() manipulates both ctrl_val[], mbps_val[] and the
hardware. The mbps_val[] that matches the mba_sc state of the resource
is changed, but the other is left unchanged. Abstracting this is the
subject of later patches that affect set_mba_sc() too.

Signed-off-by: default avatarJames Morse <james.morse@arm.com>
Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
Reviewed-by: default avatarJamie Iles <jamie@nuviainc.com>
Reviewed-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Tested-by: default avatarBabu Moger <babu.moger@amd.com>
Link: https://lkml.kernel.org/r/20210728170637.25610-17-james.morse@arm.com
parent 2e667819

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

+12 −4
Original line number Diff line number Diff line
@@ -401,22 +401,30 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of, 
	return ret ?: nbytes;

}



void resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d,

			     u32 closid, u32 *value)

{

	struct rdt_hw_domain *hw_dom = resctrl_to_arch_dom(d);



	if (!is_mba_sc(r))

		*value = hw_dom->ctrl_val[closid];

	else

		*value = hw_dom->mbps_val[closid];

}



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

{

	struct rdt_resource *r = schema->res;

	struct rdt_hw_domain *hw_dom;

	struct rdt_domain *dom;

	bool sep = false;

	u32 ctrl_val;



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

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

		hw_dom = resctrl_to_arch_dom(dom);

		if (sep)

			seq_puts(s, ";");



		ctrl_val = (!is_mba_sc(r) ? hw_dom->ctrl_val[closid] :

			    hw_dom->mbps_val[closid]);

		resctrl_arch_get_config(r, dom, closid, &ctrl_val);

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

			   ctrl_val);

		sep = true;

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

+5 −1
Original line number Diff line number Diff line
@@ -442,8 +442,12 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_domain *dom_mbm) 
	hw_dom_mba = resctrl_to_arch_dom(dom_mba);



	cur_bw = pmbm_data->prev_bw;

	user_bw = hw_dom_mba->mbps_val[closid];

	resctrl_arch_get_config(r_mba, dom_mba, closid, &user_bw);

	delta_bw = pmbm_data->delta_bw;

	/*

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

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

	 */

	cur_msr_val = hw_dom_mba->ctrl_val[closid];



	/*

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

+18 −25
Original line number Diff line number Diff line
@@ -910,27 +910,27 @@ static int rdt_bit_usage_show(struct kernfs_open_file *of, 
	int i, hwb, swb, excl, psl;

	enum rdtgrp_mode mode;

	bool sep = false;

	u32 *ctrl;

	u32 ctrl_val;



	mutex_lock(&rdtgroup_mutex);

	hw_shareable = r->cache.shareable_bits;

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

		if (sep)

			seq_putc(seq, ';');

		ctrl = resctrl_to_arch_dom(dom)->ctrl_val;

		sw_shareable = 0;

		exclusive = 0;

		seq_printf(seq, "%d=", dom->id);

		for (i = 0; i < closids_supported(); i++, ctrl++) {

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

			if (!closid_allocated(i))

				continue;

			resctrl_arch_get_config(r, dom, i, &ctrl_val);

			mode = rdtgroup_mode_by_closid(i);

			switch (mode) {

			case RDT_MODE_SHAREABLE:

				sw_shareable |= *ctrl;

				sw_shareable |= ctrl_val;

				break;

			case RDT_MODE_EXCLUSIVE:

				exclusive |= *ctrl;

				exclusive |= ctrl_val;

				break;

			case RDT_MODE_PSEUDO_LOCKSETUP:

			/*
@@ -1188,7 +1188,6 @@ static bool __rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d 
{

	enum rdtgrp_mode mode;

	unsigned long ctrl_b;

	u32 *ctrl;

	int i;



	/* Check for any overlap with regions used by hardware directly */
@@ -1199,9 +1198,8 @@ static bool __rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d 
	}



	/* Check for overlap with other resource groups */

	ctrl = resctrl_to_arch_dom(d)->ctrl_val;

	for (i = 0; i < closids_supported(); i++, ctrl++) {

		ctrl_b = *ctrl;

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

		resctrl_arch_get_config(r, d, i, (u32 *)&ctrl_b);

		mode = rdtgroup_mode_by_closid(i);

		if (closid_allocated(i) && i != closid &&

		    mode != RDT_MODE_PSEUDO_LOCKSETUP) {
@@ -1269,12 +1267,12 @@ bool rdtgroup_cbm_overlaps(struct resctrl_schema *s, struct rdt_domain *d, 
 */

static bool rdtgroup_mode_test_exclusive(struct rdtgroup *rdtgrp)

{

	struct rdt_hw_domain *hw_dom;

	int closid = rdtgrp->closid;

	struct resctrl_schema *s;

	struct rdt_resource *r;

	bool has_cache = false;

	struct rdt_domain *d;

	u32 ctrl;



	list_for_each_entry(s, &resctrl_schema_all, list) {

		r = s->res;
@@ -1282,10 +1280,8 @@ static bool rdtgroup_mode_test_exclusive(struct rdtgroup *rdtgrp) 
			continue;

		has_cache = true;

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

			hw_dom = resctrl_to_arch_dom(d);

			if (rdtgroup_cbm_overlaps(s, d,

						  hw_dom->ctrl_val[closid],

						  rdtgrp->closid, false)) {

			resctrl_arch_get_config(r, d, closid, &ctrl);

			if (rdtgroup_cbm_overlaps(s, d, ctrl, closid, false)) {

				rdt_last_cmd_puts("Schemata overlaps\n");

				return false;

			}
@@ -1417,7 +1413,6 @@ static int rdtgroup_size_show(struct kernfs_open_file *of, 
			      struct seq_file *s, void *v)

{

	struct resctrl_schema *schema;

	struct rdt_hw_domain *hw_dom;

	struct rdtgroup *rdtgrp;

	struct rdt_resource *r;

	struct rdt_domain *d;
@@ -1453,15 +1448,13 @@ static int rdtgroup_size_show(struct kernfs_open_file *of, 
		sep = false;

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

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

			hw_dom = resctrl_to_arch_dom(d);

			if (sep)

				seq_putc(s, ';');

			if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {

				size = 0;

			} else {

				ctrl = (!is_mba_sc(r) ?

						hw_dom->ctrl_val[rdtgrp->closid] :

						hw_dom->mbps_val[rdtgrp->closid]);

				resctrl_arch_get_config(r, d, rdtgrp->closid,

							&ctrl);

				if (r->rid == RDT_RESOURCE_MBA)

					size = ctrl;

				else
@@ -2759,7 +2752,7 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s, 
	u32 used_b = 0, unused_b = 0;

	unsigned long tmp_cbm;

	enum rdtgrp_mode mode;

	u32 peer_ctl, *ctrl;

	u32 peer_ctl, ctrl_val;

	int i;



	rdt_cdp_peer_get(r, d, &r_cdp, &d_cdp);
@@ -2767,8 +2760,7 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s, 
	cfg->have_new_ctrl = false;

	cfg->new_ctrl = r->cache.shareable_bits;

	used_b = r->cache.shareable_bits;

	ctrl = resctrl_to_arch_dom(d)->ctrl_val;

	for (i = 0; i < closids_supported(); i++, ctrl++) {

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

		if (closid_allocated(i) && i != closid) {

			mode = rdtgroup_mode_by_closid(i);

			if (mode == RDT_MODE_PSEUDO_LOCKSETUP)
@@ -2784,12 +2776,13 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s, 
			 * with an exclusive group.

			 */

			if (d_cdp)

				peer_ctl = resctrl_to_arch_dom(d_cdp)->ctrl_val[i];

				resctrl_arch_get_config(r_cdp, d_cdp, i, &peer_ctl);

			else

				peer_ctl = 0;

			used_b |= *ctrl | peer_ctl;

			resctrl_arch_get_config(r, d, i, &ctrl_val);

			used_b |= ctrl_val | peer_ctl;

			if (mode == RDT_MODE_SHAREABLE)

				cfg->new_ctrl |= *ctrl | peer_ctl;

				cfg->new_ctrl |= ctrl_val | peer_ctl;

		}

	}

	if (d->plr && d->plr->cbm > 0)

include/linux/resctrl.h

+2 −0
Original line number Diff line number Diff line
@@ -200,5 +200,7 @@ struct resctrl_schema { 
/* The number of closid supported by this resource regardless of CDP */

u32 resctrl_arch_get_num_closid(struct rdt_resource *r);

int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);

void resctrl_arch_get_config(struct rdt_resource *r, struct rdt_domain *d,

			     u32 closid, u32 *value);



#endif /* _RESCTRL_H */