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x86/resctrl: Remove rdt_cdp_peer_get()

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When CDP is enabled, rdt_cdp_peer_get() finds the alternative
CODE/DATA resource and returns the alternative domain. This is used
to determine if bitmaps overlap when there are aliased entries
in the two struct rdt_hw_resources.

Now that the ctrl_val[] used by the CODE/DATA resources is the same,
the search for an alternate resource/domain is not needed.

Replace rdt_cdp_peer_get() with resctrl_peer_type(), which returns
the alternative type. This can be passed to resctrl_arch_get_config()
with the same resource and domain.

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/20210728170637.25610-23-james.morse@arm.com
This commit is contained in:
James Morse 2021-07-28 17:06:35 +00:00 committed by Borislav Petkov
parent 43ac1dbf61
commit fbc06c6980
1 changed files with 14 additions and 85 deletions
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99
arch/x86/kernel/cpu/resctrl/rdtgroup.c
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@ -1092,82 +1092,17 @@ static int rdtgroup_mode_show(struct kernfs_open_file *of,
return 0;
}
/**
* rdt_cdp_peer_get - Retrieve CDP peer if it exists
* @r: RDT resource to which RDT domain @d belongs
* @d: Cache instance for which a CDP peer is requested
* @r_cdp: RDT resource that shares hardware with @r (RDT resource peer)
* Used to return the result.
* @d_cdp: RDT domain that shares hardware with @d (RDT domain peer)
* Used to return the result.
* @peer_type: The CDP configuration type of the peer resource.
*
* RDT resources are managed independently and by extension the RDT domains
* (RDT resource instances) are managed independently also. The Code and
* Data Prioritization (CDP) RDT resources, while managed independently,
* could refer to the same underlying hardware. For example,
* RDT_RESOURCE_L2CODE and RDT_RESOURCE_L2DATA both refer to the L2 cache.
*
* When provided with an RDT resource @r and an instance of that RDT
* resource @d rdt_cdp_peer_get() will return if there is a peer RDT
* resource and the exact instance that shares the same hardware.
*
* Return: 0 if a CDP peer was found, <0 on error or if no CDP peer exists.
* If a CDP peer was found, @r_cdp will point to the peer RDT resource
* and @d_cdp will point to the peer RDT domain.
*/
static int rdt_cdp_peer_get(struct rdt_resource *r, struct rdt_domain *d,
struct rdt_resource **r_cdp,
struct rdt_domain **d_cdp,
enum resctrl_conf_type *peer_type)
static enum resctrl_conf_type resctrl_peer_type(enum resctrl_conf_type my_type)
{
struct rdt_resource *_r_cdp = NULL;
struct rdt_domain *_d_cdp = NULL;
int ret = 0;
switch (r->rid) {
case RDT_RESOURCE_L3DATA:
_r_cdp = &rdt_resources_all[RDT_RESOURCE_L3CODE].r_resctrl;
*peer_type = CDP_CODE;
break;
case RDT_RESOURCE_L3CODE:
_r_cdp = &rdt_resources_all[RDT_RESOURCE_L3DATA].r_resctrl;
*peer_type = CDP_DATA;
break;
case RDT_RESOURCE_L2DATA:
_r_cdp = &rdt_resources_all[RDT_RESOURCE_L2CODE].r_resctrl;
*peer_type = CDP_CODE;
break;
case RDT_RESOURCE_L2CODE:
_r_cdp = &rdt_resources_all[RDT_RESOURCE_L2DATA].r_resctrl;
*peer_type = CDP_DATA;
break;
switch (my_type) {
case CDP_CODE:
return CDP_DATA;
case CDP_DATA:
return CDP_CODE;
default:
ret = -ENOENT;
goto out;
case CDP_NONE:
return CDP_NONE;
}
/*
* When a new CPU comes online and CDP is enabled then the new
* RDT domains (if any) associated with both CDP RDT resources
* are added in the same CPU online routine while the
* rdtgroup_mutex is held. It should thus not happen for one
* RDT domain to exist and be associated with its RDT CDP
* resource but there is no RDT domain associated with the
* peer RDT CDP resource. Hence the WARN.
*/
_d_cdp = rdt_find_domain(_r_cdp, d->id, NULL);
if (WARN_ON(IS_ERR_OR_NULL(_d_cdp))) {
_r_cdp = NULL;
_d_cdp = NULL;
ret = -EINVAL;
}
out:
*r_cdp = _r_cdp;
*d_cdp = _d_cdp;
return ret;
}
/**
@ -1248,19 +1183,16 @@ static bool __rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d
bool rdtgroup_cbm_overlaps(struct resctrl_schema *s, struct rdt_domain *d,
unsigned long cbm, int closid, bool exclusive)
{
enum resctrl_conf_type peer_type;
enum resctrl_conf_type peer_type = resctrl_peer_type(s->conf_type);
struct rdt_resource *r = s->res;
struct rdt_resource *r_cdp;
struct rdt_domain *d_cdp;
if (__rdtgroup_cbm_overlaps(r, d, cbm, closid, s->conf_type,
exclusive))
return true;
if (rdt_cdp_peer_get(r, d, &r_cdp, &d_cdp, &peer_type) < 0)
if (!resctrl_arch_get_cdp_enabled(r->rid))
return false;
return __rdtgroup_cbm_overlaps(r_cdp, d_cdp, cbm, closid, peer_type, exclusive);
return __rdtgroup_cbm_overlaps(r, d, cbm, closid, peer_type, exclusive);
}
/**
@ -2756,11 +2688,9 @@ static u32 cbm_ensure_valid(u32 _val, struct rdt_resource *r)
static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s,
u32 closid)
{
enum resctrl_conf_type peer_type = resctrl_peer_type(s->conf_type);
enum resctrl_conf_type t = s->conf_type;
struct rdt_resource *r_cdp = NULL;
struct resctrl_staged_config *cfg;
enum resctrl_conf_type peer_type;
struct rdt_domain *d_cdp = NULL;
struct rdt_resource *r = s->res;
u32 used_b = 0, unused_b = 0;
unsigned long tmp_cbm;
@ -2768,7 +2698,6 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s,
u32 peer_ctl, ctrl_val;
int i;
rdt_cdp_peer_get(r, d, &r_cdp, &d_cdp, &peer_type);
cfg = &d->staged_config[t];
cfg->have_new_ctrl = false;
cfg->new_ctrl = r->cache.shareable_bits;
@ -2788,8 +2717,8 @@ static int __init_one_rdt_domain(struct rdt_domain *d, struct resctrl_schema *s,
* usage to ensure there is no overlap
* with an exclusive group.
*/
if (d_cdp)
resctrl_arch_get_config(r_cdp, d_cdp, i, peer_type, &peer_ctl);
if (resctrl_arch_get_cdp_enabled(r->rid))
resctrl_arch_get_config(r, d, i, peer_type, &peer_ctl);
else
peer_ctl = 0;
resctrl_arch_get_config(r, d, i, s->conf_type, &ctrl_val);