2021-05-19 20:16:14

by James Morse

[permalink] [raw]
Subject: [PATCH v3 06/24] x86/resctrl: Walk the resctrl schema list instead of an arch list

When parsing a schema configuration value from user-space, resctrl
walks the architectures rdt_resources_all[] array to find a
matching struct rdt_resource.

Once the CDP resources are merged there will be one resource in
use by two schema. Anything walking rdt_resources_all[] on behalf
of a user-space request should walk the list of struct resctrl_schema
instead.

Change the users of for_each_alloc_enabled_rdt_resource() to walk
the schema instead. Schema were only created for alloc_enabled resources
so these two lists are currently equivalent.
schemata_list_create() and rdt_kill_sb() are ignored. The first
creates the schema list, and will eventually loop over the resource
indexes using an arch helper to retrieve the resource. rdt_kill_sb()
will eventually make use of an arch 'reset everything' helper.
After the filesystem code is moved, rdtgroup_pseudo_locked_in_hierarchy()
remains part of the x86 specific hooks to support psuedo lock. This code
walks each domain, and still does this after the separate resources are
merged.

Reviewed-by: Jamie Iles <[email protected]>
Signed-off-by: James Morse <[email protected]>
---
Changes since v2:
* Shuffled commit message,

Changes since v1:
* Expanded commit message
* Split from a larger patch
---
arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 23 +++++++++++++++--------
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 18 ++++++++++++------
2 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 2e7466659af3..a6f9548a8a59 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -287,10 +287,12 @@ static int rdtgroup_parse_resource(char *resname, char *tok,
struct rdtgroup *rdtgrp)
{
struct rdt_hw_resource *hw_res;
+ struct resctrl_schema *s;
struct rdt_resource *r;

- for_each_alloc_enabled_rdt_resource(r) {
- hw_res = resctrl_to_arch_res(r);
+ list_for_each_entry(s, &resctrl_schema_all, list) {
+ r = s->res;
+ hw_res = resctrl_to_arch_res(s->res);
if (!strcmp(resname, r->name) && rdtgrp->closid < hw_res->num_closid)
return parse_line(tok, r, rdtgrp);
}
@@ -301,6 +303,7 @@ static int rdtgroup_parse_resource(char *resname, char *tok,
ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
char *buf, size_t nbytes, loff_t off)
{
+ struct resctrl_schema *s;
struct rdtgroup *rdtgrp;
struct rdt_domain *dom;
struct rdt_resource *r;
@@ -331,8 +334,8 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
goto out;
}

- for_each_alloc_enabled_rdt_resource(r) {
- list_for_each_entry(dom, &r->domains, list)
+ list_for_each_entry(s, &resctrl_schema_all, list) {
+ list_for_each_entry(dom, &s->res->domains, list)
dom->have_new_ctrl = false;
}

@@ -353,7 +356,8 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
goto out;
}

- for_each_alloc_enabled_rdt_resource(r) {
+ list_for_each_entry(s, &resctrl_schema_all, list) {
+ r = s->res;
ret = update_domains(r, rdtgrp->closid);
if (ret)
goto out;
@@ -401,6 +405,7 @@ int rdtgroup_schemata_show(struct kernfs_open_file *of,
struct seq_file *s, void *v)
{
struct rdt_hw_resource *hw_res;
+ struct resctrl_schema *schema;
struct rdtgroup *rdtgrp;
struct rdt_resource *r;
int ret = 0;
@@ -409,8 +414,10 @@ int rdtgroup_schemata_show(struct kernfs_open_file *of,
rdtgrp = rdtgroup_kn_lock_live(of->kn);
if (rdtgrp) {
if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
- for_each_alloc_enabled_rdt_resource(r)
+ list_for_each_entry(schema, &resctrl_schema_all, list) {
+ r = schema->res;
seq_printf(s, "%s:uninitialized\n", r->name);
+ }
} else if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
if (!rdtgrp->plr->d) {
rdt_last_cmd_clear();
@@ -424,8 +431,8 @@ int rdtgroup_schemata_show(struct kernfs_open_file *of,
}
} else {
closid = rdtgrp->closid;
- for_each_alloc_enabled_rdt_resource(r) {
- hw_res = resctrl_to_arch_res(r);
+ list_for_each_entry(schema, &resctrl_schema_all, list) {
+ hw_res = resctrl_to_arch_res(schema->res);
if (closid < hw_res->num_closid)
show_doms(s, r, closid);
}
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 199b3035dfbf..aad891d691e0 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -104,12 +104,12 @@ int closids_supported(void)
static void closid_init(void)
{
struct rdt_hw_resource *hw_res;
- struct rdt_resource *r;
+ struct resctrl_schema *s;
int rdt_min_closid = 32;

/* Compute rdt_min_closid across all resources */
- for_each_alloc_enabled_rdt_resource(r) {
- hw_res = resctrl_to_arch_res(r);
+ list_for_each_entry(s, &resctrl_schema_all, list) {
+ hw_res = resctrl_to_arch_res(s->res);
rdt_min_closid = min(rdt_min_closid, hw_res->num_closid);
}

@@ -1276,11 +1276,13 @@ 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;

- for_each_alloc_enabled_rdt_resource(r) {
+ list_for_each_entry(s, &resctrl_schema_all, list) {
+ r = s->res;
if (r->rid == RDT_RESOURCE_MBA)
continue;
has_cache = true;
@@ -1418,6 +1420,7 @@ unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r,
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;
@@ -1449,7 +1452,8 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
goto out;
}

- for_each_alloc_enabled_rdt_resource(r) {
+ list_for_each_entry(schema, &resctrl_schema_all, list) {
+ r = schema->res;
sep = false;
seq_printf(s, "%*s:", max_name_width, r->name);
list_for_each_entry(d, &r->domains, list) {
@@ -2815,10 +2819,12 @@ static void rdtgroup_init_mba(struct rdt_resource *r)
/* Initialize the RDT group's allocations. */
static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
{
+ struct resctrl_schema *s;
struct rdt_resource *r;
int ret;

- for_each_alloc_enabled_rdt_resource(r) {
+ list_for_each_entry(s, &resctrl_schema_all, list) {
+ r = s->res;
if (r->rid == RDT_RESOURCE_MBA) {
rdtgroup_init_mba(r);
} else {
--
2.30.2