Skip to content

Commit

Permalink
x86/resctrl: Group staged configuration into a separate struct
Browse files Browse the repository at this point in the history 
When configuration changes are made, the new value is written to struct
rdt_domain's new_ctrl field and the have_new_ctrl flag is set. Later
new_ctrl is copied to hardware by a call to update_domains().

Once the CDP resources are merged, there will be one new_ctrl field in
use by two struct resctrl_schema requiring a per-schema IPI to copy the
value to hardware.

Move new_ctrl and have_new_ctrl into a new struct resctrl_staged_config.
Before the CDP resources can be merged, struct rdt_domain will need an
array of these, one per type of configuration. Using the type as an
index to the array will ensure that a schema configuration string can't
specify the same domain twice.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jamie Iles <jamie@nuviainc.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lkml.kernel.org/r/20210728170637.25610-14-james.morse@arm.com
  • Loading branch information
James Morse authored and Borislav Petkov committed Aug 11, 2021
1 parent e198fde commit e8f7282
Show file tree
Hide file tree
Showing 3 changed files with 54 additions and 27 deletions.
43 changes: 29 additions & 14 deletions arch/x86/kernel/cpu/resctrl/ctrlmondata.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -62,16 +62,17 @@ int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
{
struct rdt_resource *r = s->res;
unsigned long bw_val;
struct resctrl_staged_config *cfg = &d->staged_config;

if (d->have_new_ctrl) {
if (cfg->have_new_ctrl) {
rdt_last_cmd_printf("Duplicate domain %d\n", d->id);
return -EINVAL;
}

if (!bw_validate(data->buf, &bw_val, r))
return -EINVAL;
d->new_ctrl = bw_val;
d->have_new_ctrl = true;
cfg->new_ctrl = bw_val;
cfg->have_new_ctrl = true;

return 0;
}
Expand Down Expand Up @@ -129,11 +130,12 @@ static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
struct rdt_domain *d)
{
struct resctrl_staged_config *cfg = &d->staged_config;
struct rdtgroup *rdtgrp = data->rdtgrp;
struct rdt_resource *r = s->res;
u32 cbm_val;

if (d->have_new_ctrl) {
if (cfg->have_new_ctrl) {
rdt_last_cmd_printf("Duplicate domain %d\n", d->id);
return -EINVAL;
}
Expand Down Expand Up @@ -175,8 +177,8 @@ int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
}
}

d->new_ctrl = cbm_val;
d->have_new_ctrl = true;
cfg->new_ctrl = cbm_val;
cfg->have_new_ctrl = true;

return 0;
}
Expand All @@ -190,6 +192,7 @@ int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
static int parse_line(char *line, struct resctrl_schema *s,
struct rdtgroup *rdtgrp)
{
struct resctrl_staged_config *cfg;
struct rdt_resource *r = s->res;
struct rdt_parse_data data;
char *dom = NULL, *id;
Expand Down Expand Up @@ -219,6 +222,7 @@ static int parse_line(char *line, struct resctrl_schema *s,
if (r->parse_ctrlval(&data, s, d))
return -EINVAL;
if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
cfg = &d->staged_config;
/*
* In pseudo-locking setup mode and just
* parsed a valid CBM that should be
Expand All @@ -229,7 +233,7 @@ static int parse_line(char *line, struct resctrl_schema *s,
*/
rdtgrp->plr->s = s;
rdtgrp->plr->d = d;
rdtgrp->plr->cbm = d->new_ctrl;
rdtgrp->plr->cbm = cfg->new_ctrl;
d->plr = rdtgrp->plr;
return 0;
}
Expand All @@ -239,14 +243,27 @@ static int parse_line(char *line, struct resctrl_schema *s,
return -EINVAL;
}

static void apply_config(struct rdt_hw_domain *hw_dom,
struct resctrl_staged_config *cfg, int closid,
cpumask_var_t cpu_mask, bool mba_sc)
{
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[closid]) {
cpumask_set_cpu(cpumask_any(&dom->cpu_mask), cpu_mask);
dc[closid] = cfg->new_ctrl;
}
}

int update_domains(struct rdt_resource *r, int closid)
{
struct resctrl_staged_config *cfg;
struct rdt_hw_domain *hw_dom;
struct msr_param msr_param;
cpumask_var_t cpu_mask;
struct rdt_domain *d;
bool mba_sc;
u32 *dc;
int cpu;

if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
Expand All @@ -259,11 +276,9 @@ int update_domains(struct rdt_resource *r, int closid)
mba_sc = is_mba_sc(r);
list_for_each_entry(d, &r->domains, list) {
hw_dom = resctrl_to_arch_dom(d);
dc = !mba_sc ? hw_dom->ctrl_val : hw_dom->mbps_val;
if (d->have_new_ctrl && d->new_ctrl != dc[closid]) {
cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
dc[closid] = d->new_ctrl;
}
cfg = &hw_dom->d_resctrl.staged_config;
if (cfg->have_new_ctrl)
apply_config(hw_dom, cfg, closid, cpu_mask, mba_sc);
}

/*
Expand Down Expand Up @@ -335,7 +350,7 @@ ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,

list_for_each_entry(s, &resctrl_schema_all, list) {
list_for_each_entry(dom, &s->res->domains, list)
dom->have_new_ctrl = false;
memset(&dom->staged_config, 0, sizeof(dom->staged_config));
}

while ((tok = strsep(&buf, "\n")) != NULL) {
Expand Down
22 changes: 13 additions & 9 deletions arch/x86/kernel/cpu/resctrl/rdtgroup.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2752,6 +2752,7 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s,
u32 closid)
{
struct rdt_resource *r_cdp = NULL;
struct resctrl_staged_config *cfg;
struct rdt_domain *d_cdp = NULL;
struct rdt_resource *r = s->res;
u32 used_b = 0, unused_b = 0;
Expand All @@ -2761,8 +2762,9 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s,
int i;

rdt_cdp_peer_get(r, d, &r_cdp, &d_cdp);
d->have_new_ctrl = false;
d->new_ctrl = r->cache.shareable_bits;
cfg = &d->staged_config;
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++) {
Expand All @@ -2786,29 +2788,29 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s,
peer_ctl = 0;
used_b |= *ctrl | peer_ctl;
if (mode == RDT_MODE_SHAREABLE)
d->new_ctrl |= *ctrl | peer_ctl;
cfg->new_ctrl |= *ctrl | peer_ctl;
}
}
if (d->plr && d->plr->cbm > 0)
used_b |= d->plr->cbm;
unused_b = used_b ^ (BIT_MASK(r->cache.cbm_len) - 1);
unused_b &= BIT_MASK(r->cache.cbm_len) - 1;
d->new_ctrl |= unused_b;
cfg->new_ctrl |= unused_b;
/*
* Force the initial CBM to be valid, user can
* modify the CBM based on system availability.
*/
d->new_ctrl = cbm_ensure_valid(d->new_ctrl, r);
cfg->new_ctrl = cbm_ensure_valid(cfg->new_ctrl, r);
/*
* Assign the u32 CBM to an unsigned long to ensure that
* bitmap_weight() does not access out-of-bound memory.
*/
tmp_cbm = d->new_ctrl;
tmp_cbm = cfg->new_ctrl;
if (bitmap_weight(&tmp_cbm, r->cache.cbm_len) < r->cache.min_cbm_bits) {
rdt_last_cmd_printf("No space on %s:%d\n", s->name, d->id);
return -ENOSPC;
}
d->have_new_ctrl = true;
cfg->have_new_ctrl = true;

return 0;
}
Expand Down Expand Up @@ -2840,11 +2842,13 @@ static int rdtgroup_init_cat(struct resctrl_schema *s, u32 closid)
/* Initialize MBA resource with default values. */
static void rdtgroup_init_mba(struct rdt_resource *r)
{
struct resctrl_staged_config *cfg;
struct rdt_domain *d;

list_for_each_entry(d, &r->domains, list) {
d->new_ctrl = is_mba_sc(r) ? MBA_MAX_MBPS : r->default_ctrl;
d->have_new_ctrl = true;
cfg = &d->staged_config;
cfg->new_ctrl = is_mba_sc(r) ? MBA_MAX_MBPS : r->default_ctrl;
cfg->have_new_ctrl = true;
}
}

Expand Down
16 changes: 12 additions & 4 deletions include/linux/resctrl.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -27,13 +27,21 @@ enum resctrl_conf_type {
CDP_DATA,
};

/**
* struct resctrl_staged_config - parsed configuration to be applied
* @new_ctrl: new ctrl value to be loaded
* @have_new_ctrl: whether the user provided new_ctrl is valid
*/
struct resctrl_staged_config {
u32 new_ctrl;
bool have_new_ctrl;
};

/**
* struct rdt_domain - group of CPUs sharing a resctrl resource
* @list: all instances of this resource
* @id: unique id for this instance
* @cpu_mask: which CPUs share this resource
* @new_ctrl: new ctrl value to be loaded
* @have_new_ctrl: did user provide new_ctrl for this domain
* @rmid_busy_llc: bitmap of which limbo RMIDs are above threshold
* @mbm_total: saved state for MBM total bandwidth
* @mbm_local: saved state for MBM local bandwidth
Expand All @@ -42,13 +50,12 @@ enum resctrl_conf_type {
* @mbm_work_cpu: worker CPU for MBM h/w counters
* @cqm_work_cpu: worker CPU for CQM h/w counters
* @plr: pseudo-locked region (if any) associated with domain
* @staged_config: parsed configuration to be applied
*/
struct rdt_domain {
struct list_head list;
int id;
struct cpumask cpu_mask;
u32 new_ctrl;
bool have_new_ctrl;
unsigned long *rmid_busy_llc;
struct mbm_state *mbm_total;
struct mbm_state *mbm_local;
Expand All @@ -57,6 +64,7 @@ struct rdt_domain {
int mbm_work_cpu;
int cqm_work_cpu;
struct pseudo_lock_region *plr;
struct resctrl_staged_config staged_config;
};

/**
Expand Down

0 comments on commit e8f7282

Please sign in to comment.