[PATCH v2 24/24] x86/resctrl: Merge the CDP resources

[James Morse <james.morse@arm.com>]

Now that resctrl uses the schema's configuration type is the source of
CODE/DATA configuration styles, and there is only one configuration
array between the three views of the resource, remove the CODE and DATA
aliases.

This allows the alloc_ctrlval_array() and complications around free()ing
the ctrl_val arrays to be removed.

To continue providing the CDP user-interface, the resctrl filesystem
code creates two schema for one resource when CDP is enabled, and
generates the names itself. This ensures the user interface is the
same when another architecture emulates CDPs behaviour.

Reviewed-by: Jamie Iles <jamie@nuviainc.com>
Signed-off-by: James Morse <james.morse@arm.com>
---
Changes since v1:
 * rdt_get_cdp_config() is kept for its comment.
---
 arch/x86/kernel/cpu/resctrl/core.c     | 174 ++-----------------------
 arch/x86/kernel/cpu/resctrl/internal.h |   4 -
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 122 ++++++++---------
 3 files changed, 75 insertions(+), 225 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 5021a726e87d..7c20d0469b3a 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -78,42 +78,6 @@ struct rdt_hw_resource rdt_resources_all[] = {
 		.msr_base		= MSR_IA32_L3_CBM_BASE,
 		.msr_update		= cat_wrmsr,
 	},
-	[RDT_RESOURCE_L3DATA] =
-	{
-		.conf_type			= CDP_DATA,
-		.resctrl = {
-			.rid			= RDT_RESOURCE_L3DATA,
-			.name			= "L3DATA",
-			.cache_level		= 3,
-			.cache = {
-				.min_cbm_bits	= 1,
-			},
-			.domains		= domain_init(RDT_RESOURCE_L3DATA),
-			.parse_ctrlval		= parse_cbm,
-			.format_str		= "%d=%0*x",
-			.fflags			= RFTYPE_RES_CACHE,
-		},
-		.msr_base		= MSR_IA32_L3_CBM_BASE,
-		.msr_update		= cat_wrmsr,
-	},
-	[RDT_RESOURCE_L3CODE] =
-	{
-		.conf_type			= CDP_CODE,
-		.resctrl = {
-			.rid			= RDT_RESOURCE_L3CODE,
-			.name			= "L3CODE",
-			.cache_level		= 3,
-			.cache = {
-				.min_cbm_bits	= 1,
-			},
-			.domains		= domain_init(RDT_RESOURCE_L3CODE),
-			.parse_ctrlval		= parse_cbm,
-			.format_str		= "%d=%0*x",
-			.fflags			= RFTYPE_RES_CACHE,
-		},
-		.msr_base		= MSR_IA32_L3_CBM_BASE,
-		.msr_update		= cat_wrmsr,
-	},
 	[RDT_RESOURCE_L2] =
 	{
 		.conf_type			= CDP_BOTH,
@@ -132,42 +96,6 @@ struct rdt_hw_resource rdt_resources_all[] = {
 		.msr_base		= MSR_IA32_L2_CBM_BASE,
 		.msr_update		= cat_wrmsr,
 	},
-	[RDT_RESOURCE_L2DATA] =
-	{
-		.conf_type			= CDP_DATA,
-		.resctrl = {
-			.rid			= RDT_RESOURCE_L2DATA,
-			.name			= "L2DATA",
-			.cache_level		= 2,
-			.cache = {
-				.min_cbm_bits	= 1,
-			},
-			.domains		= domain_init(RDT_RESOURCE_L2DATA),
-			.parse_ctrlval		= parse_cbm,
-			.format_str		= "%d=%0*x",
-			.fflags			= RFTYPE_RES_CACHE,
-		},
-		.msr_base		= MSR_IA32_L2_CBM_BASE,
-		.msr_update		= cat_wrmsr,
-	},
-	[RDT_RESOURCE_L2CODE] =
-	{
-		.conf_type			= CDP_CODE,
-		.resctrl = {
-			.rid			= RDT_RESOURCE_L2CODE,
-			.name			= "L2CODE",
-			.cache_level		= 2,
-			.cache = {
-				.min_cbm_bits	= 1,
-			},
-			.domains		= domain_init(RDT_RESOURCE_L2CODE),
-			.parse_ctrlval		= parse_cbm,
-			.format_str		= "%d=%0*x",
-			.fflags			= RFTYPE_RES_CACHE,
-		},
-		.msr_base		= MSR_IA32_L2_CBM_BASE,
-		.msr_update		= cat_wrmsr,
-	},
 	[RDT_RESOURCE_MBA] =
 	{
 		.conf_type			= CDP_BOTH,
@@ -339,40 +267,24 @@ static void rdt_get_cache_alloc_cfg(int idx, struct rdt_resource *r)
 	r->alloc_enabled = true;
 }
 
-static void rdt_get_cdp_config(int level, int type)
+static void rdt_get_cdp_config(int level)
 {
-	struct rdt_resource *r_l = &rdt_resources_all[level].resctrl;
-	struct rdt_hw_resource *hw_res_l = resctrl_to_arch_res(r_l);
-	struct rdt_resource *r = &rdt_resources_all[type].resctrl;
-	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
-
-	hw_res->num_closid = hw_res_l->num_closid;
-	r->cache.cbm_len = r_l->cache.cbm_len;
-	r->default_ctrl = r_l->default_ctrl;
-	r->cache.shareable_bits = r_l->cache.shareable_bits;
-	r->data_width = (r->cache.cbm_len + 3) / 4;
-	r->alloc_capable = true;
 	/*
 	 * By default, CDP is disabled. CDP can be enabled by mount parameter
 	 * "cdp" during resctrl file system mount time.
 	 */
-	r->alloc_enabled = false;
 	rdt_resources_all[level].cdp_enabled = false;
-	rdt_resources_all[type].cdp_enabled = false;
 	rdt_resources_all[level].cdp_capable = true;
-	rdt_resources_all[type].cdp_capable = true;
 }
 
 static void rdt_get_cdp_l3_config(void)
 {
-	rdt_get_cdp_config(RDT_RESOURCE_L3, RDT_RESOURCE_L3DATA);
-	rdt_get_cdp_config(RDT_RESOURCE_L3, RDT_RESOURCE_L3CODE);
+	rdt_get_cdp_config(RDT_RESOURCE_L3);
 }
 
 static void rdt_get_cdp_l2_config(void)
 {
-	rdt_get_cdp_config(RDT_RESOURCE_L2, RDT_RESOURCE_L2DATA);
-	rdt_get_cdp_config(RDT_RESOURCE_L2, RDT_RESOURCE_L2CODE);
+	rdt_get_cdp_config(RDT_RESOURCE_L2);
 }
 
 static void
@@ -509,58 +421,6 @@ void setup_default_ctrlval(struct rdt_resource *r, u32 *dc, u32 *dm)
 	}
 }
 
-static u32 *alloc_ctrlval_array(struct rdt_resource *r, struct rdt_domain *d,
-				bool mba_sc)
-{
-	/* these are for the underlying hardware, they may not match r/d */
-	struct rdt_domain *underlying_domain;
-	struct rdt_hw_resource *hw_res;
-	struct rdt_hw_domain *hw_dom;
-	bool remapped;
-
-	switch (r->rid) {
-	case RDT_RESOURCE_L3DATA:
-	case RDT_RESOURCE_L3CODE:
-		hw_res = &rdt_resources_all[RDT_RESOURCE_L3];
-		remapped = true;
-		break;
-	case RDT_RESOURCE_L2DATA:
-	case RDT_RESOURCE_L2CODE:
-		hw_res = &rdt_resources_all[RDT_RESOURCE_L2];
-		remapped = true;
-		break;
-	default:
-		hw_res = resctrl_to_arch_res(r);
-		remapped = false;
-	}
-
-
-	/*
-	 * If we changed the resource, we need to search for the underlying
-	 * domain. Doing this for all resources would make it tricky to add the
-	 * first resource, as domains aren't added to a resource list until
-	 * after the ctrlval arrays have been allocated.
-	 */
-	if (remapped)
-		underlying_domain = rdt_find_domain(&hw_res->resctrl, d->id,
-						    NULL);
-	else
-		underlying_domain = d;
-	hw_dom = resctrl_to_arch_dom(underlying_domain);
-
-	if (mba_sc) {
-		if (hw_dom->mbps_val)
-			return hw_dom->mbps_val;
-		return kmalloc_array(hw_res->num_closid,
-				     sizeof(*hw_dom->mbps_val), GFP_KERNEL);
-	} else {
-		if (hw_dom->ctrl_val)
-			return hw_dom->ctrl_val;
-		return kmalloc_array(hw_res->num_closid,
-				     sizeof(*hw_dom->ctrl_val), GFP_KERNEL);
-	}
-}
-
 static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
@@ -568,11 +428,13 @@ static int domain_setup_ctrlval(struct rdt_resource *r, struct rdt_domain *d)
 	struct msr_param m;
 	u32 *dc, *dm;
 
-	dc = alloc_ctrlval_array(r, d, false);
+	dc = kmalloc_array(hw_res->num_closid, sizeof(*hw_dom->ctrl_val),
+			   GFP_KERNEL);
 	if (!dc)
 		return -ENOMEM;
 
-	dm = alloc_ctrlval_array(r, d, true);
+	dm = kmalloc_array(hw_res->num_closid, sizeof(*hw_dom->mbps_val),
+			   GFP_KERNEL);
 	if (!dm) {
 		kfree(dc);
 		return -ENOMEM;
@@ -731,14 +593,8 @@ static void domain_remove_cpu(int cpu, struct rdt_resource *r)
 		if (d->plr)
 			d->plr->d = NULL;
 
-		/* temporary: these four don't have a unique ctrlval array */
-		if ((r->rid != RDT_RESOURCE_L3CODE) &&
-		    (r->rid != RDT_RESOURCE_L3DATA) &&
-		    (r->rid != RDT_RESOURCE_L2CODE) &&
-		    (r->rid != RDT_RESOURCE_L2DATA)) {
-			kfree(hw_dom->ctrl_val);
-			kfree(hw_dom->mbps_val);
-		}
+		kfree(hw_dom->ctrl_val);
+		kfree(hw_dom->mbps_val);
 		bitmap_free(d->rmid_busy_llc);
 		kfree(d->mbm_total);
 		kfree(d->mbm_local);
@@ -1011,11 +867,7 @@ static __init void rdt_init_res_defs_intel(void)
 		hw_res = resctrl_to_arch_res(r);
 
 		if (r->rid == RDT_RESOURCE_L3 ||
-		    r->rid == RDT_RESOURCE_L3DATA ||
-		    r->rid == RDT_RESOURCE_L3CODE ||
-		    r->rid == RDT_RESOURCE_L2 ||
-		    r->rid == RDT_RESOURCE_L2DATA ||
-		    r->rid == RDT_RESOURCE_L2CODE) {
+		    r->rid == RDT_RESOURCE_L2) {
 			r->cache.arch_has_sparse_bitmaps = false;
 			r->cache.arch_has_empty_bitmaps = false;
 			r->cache.arch_has_per_cpu_cfg = false;
@@ -1035,11 +887,7 @@ static __init void rdt_init_res_defs_amd(void)
 		hw_res = resctrl_to_arch_res(r);
 
 		if (r->rid == RDT_RESOURCE_L3 ||
-		    r->rid == RDT_RESOURCE_L3DATA ||
-		    r->rid == RDT_RESOURCE_L3CODE ||
-		    r->rid == RDT_RESOURCE_L2 ||
-		    r->rid == RDT_RESOURCE_L2DATA ||
-		    r->rid == RDT_RESOURCE_L2CODE) {
+		    r->rid == RDT_RESOURCE_L2) {
 			r->cache.arch_has_sparse_bitmaps = true;
 			r->cache.arch_has_empty_bitmaps = true;
 			r->cache.arch_has_per_cpu_cfg = true;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index ac36249f43ba..e06bc5ccf6cd 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -402,11 +402,7 @@ extern struct dentry *debugfs_resctrl;
 
 enum resctrl_res_level {
 	RDT_RESOURCE_L3,
-	RDT_RESOURCE_L3DATA,
-	RDT_RESOURCE_L3CODE,
 	RDT_RESOURCE_L2,
-	RDT_RESOURCE_L2DATA,
-	RDT_RESOURCE_L2CODE,
 	RDT_RESOURCE_MBA,
 
 	/* Must be the last */
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 36e2905f4da6..1dfb41e1277a 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1880,10 +1880,10 @@ void rdt_domain_reconfigure_cdp(struct rdt_resource *r)
 	if (!hw_res->cdp_capable)
 		return;
 
-	if (r == &rdt_resources_all[RDT_RESOURCE_L2DATA].resctrl)
+	if (r->rid == RDT_RESOURCE_L2)
 		l2_qos_cfg_update(&hw_res->cdp_enabled);
 
-	if (r == &rdt_resources_all[RDT_RESOURCE_L3DATA].resctrl)
+	if (r->rid == RDT_RESOURCE_L3)
 		l3_qos_cfg_update(&hw_res->cdp_enabled);
 }
 
@@ -1912,68 +1912,42 @@ static int set_mba_sc(bool mba_sc)
 	return 0;
 }
 
-static int cdp_enable(int level, int data_type, int code_type)
+static int cdp_enable(int level)
 {
-	struct rdt_resource *r_ldata = &rdt_resources_all[data_type].resctrl;
-	struct rdt_resource *r_lcode = &rdt_resources_all[code_type].resctrl;
 	struct rdt_resource *r_l = &rdt_resources_all[level].resctrl;
 	int ret;
 
-	if (!r_l->alloc_capable || !r_ldata->alloc_capable ||
-	    !r_lcode->alloc_capable)
+	if (!r_l->alloc_capable)
 		return -EINVAL;
 
 	ret = set_cache_qos_cfg(level, true);
-	if (!ret) {
-		r_l->alloc_enabled = false;
-		r_ldata->alloc_enabled = true;
-		r_lcode->alloc_enabled = true;
+	if (!ret)
 		rdt_resources_all[level].cdp_enabled = true;
-		rdt_resources_all[data_type].cdp_enabled = true;
-		rdt_resources_all[code_type].cdp_enabled = true;
-	}
+
 	return ret;
 }
 
-static void cdp_disable(int level, int data_type, int code_type)
+static void cdp_disable(int level)
 {
 	struct rdt_hw_resource *r_hw = &rdt_resources_all[level];
-	struct rdt_resource *r = &r_hw->resctrl;
-
-	r->alloc_enabled = r->alloc_capable;
 
 	if (r_hw->cdp_enabled) {
-		rdt_resources_all[data_type].resctrl.alloc_enabled = false;
-		rdt_resources_all[code_type].resctrl.alloc_enabled = false;
 		set_cache_qos_cfg(level, false);
 		r_hw->cdp_enabled = false;
-		rdt_resources_all[data_type].cdp_enabled = false;
-		rdt_resources_all[code_type].cdp_enabled = false;
 	}
 }
 
 int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable)
 {
 	struct rdt_hw_resource *hw_res = &rdt_resources_all[l];
-	enum resctrl_res_level code_type, data_type;
 
 	if (!hw_res->cdp_capable)
 		return -EINVAL;
 
-	if (l == RDT_RESOURCE_L3) {
-		code_type = RDT_RESOURCE_L3CODE;
-		data_type = RDT_RESOURCE_L3DATA;
-	} else if (l == RDT_RESOURCE_L2) {
-		code_type = RDT_RESOURCE_L2CODE;
-		data_type = RDT_RESOURCE_L2DATA;
-	} else {
-		return -EINVAL;
-	}
-
 	if (enable)
-		return cdp_enable(l, data_type, code_type);
+		return cdp_enable(l);
 
-	cdp_disable(l, data_type, code_type);
+	cdp_disable(l);
 
 	return 0;
 }
@@ -2072,40 +2046,72 @@ static int rdt_enable_ctx(struct rdt_fs_context *ctx)
 	return ret;
 }
 
-static int schemata_list_create(void)
+static int schemata_list_add(struct rdt_resource *r, enum resctrl_conf_type type)
 {
-	struct rdt_resource *r;
 	struct resctrl_schema *s;
+	const char *suffix = "";
 	int ret, cl;
 
-	for_each_alloc_enabled_rdt_resource(r) {
-		s = kzalloc(sizeof(*s), GFP_KERNEL);
-		if (!s)
-			return -ENOMEM;
-
-		s->res = r;
-		s->conf_type = resctrl_to_arch_res(r)->conf_type;
-		s->num_closid = resctrl_arch_get_num_closid(r);
-		if (resctrl_arch_get_cdp_enabled(r->rid))
-			s->num_closid /= 2;
-
-		ret = snprintf(s->name, sizeof(s->name), r->name);
-		if (ret >= sizeof(s->name)) {
-			kfree(s);
-			return -EINVAL;
-		}
+	s = kzalloc(sizeof(*s), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
 
-		cl = strlen(s->name);
-		if (cl > max_name_width)
-			max_name_width = cl;
+	s->res = r;
+	s->num_closid = resctrl_arch_get_num_closid(r);
+	if (resctrl_arch_get_cdp_enabled(r->rid))
+		s->num_closid /= 2;
 
-		INIT_LIST_HEAD(&s->list);
-		list_add(&s->list, &resctrl_schema_all);
+	s->conf_type = type;
+	switch (type) {
+	case CDP_CODE:
+		suffix = "CODE";
+		break;
+	case CDP_DATA:
+		suffix = "DATA";
+		break;
+	case CDP_BOTH:
+		suffix = "";
+		break;
 	}
 
+	ret = snprintf(s->name, sizeof(s->name), "%s%s", r->name, suffix);
+	if (ret >= sizeof(s->name)) {
+		kfree(s);
+		return -EINVAL;
+	}
+
+	cl = strlen(s->name);
+	if (cl > max_name_width)
+		max_name_width = cl;
+
+	INIT_LIST_HEAD(&s->list);
+	list_add(&s->list, &resctrl_schema_all);
+
 	return 0;
 }
 
+static int schemata_list_create(void)
+{
+	struct rdt_resource *r;
+	int ret = 0;
+
+	for_each_alloc_enabled_rdt_resource(r) {
+		if (resctrl_arch_get_cdp_enabled(r->rid)) {
+			ret = schemata_list_add(r, CDP_CODE);
+			if (ret)
+				break;
+
+			ret = schemata_list_add(r, CDP_DATA);
+		} else
+			ret = schemata_list_add(r, CDP_BOTH);
+
+		if (ret)
+			break;
+	}
+
+	return ret;
+}
+
 static void schemata_list_destroy(void)
 {
 	struct resctrl_schema *s, *tmp;
-- 
2.30.0