[PATCH v5 22/40] x86/resctrl: Move mbm_cfg_mask to struct rdt_resource

From: James Morse
Date: Fri Oct 04 2024 - 14:09:57 EST


The mbm_cfg_mask field lists the bits that user-space can set when
configuring an event. This value is output via the last_cmd_status
file.

Once the filesystem parts of resctrl are moved to live in /fs/, the
struct rdt_hw_resource is inaccessible to the filesystem code. Because
this value is output to user-space, it has to be accessible to the
filesystem code.

Move it to struct rdt_resource.

Signed-off-by: James Morse <james.morse@xxxxxxx>
Tested-by: Carl Worth <carl@xxxxxxxxxxxxxxxxxxxxxx> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx>
Reviewed-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx>
---
Change since v1:
* Reword comments to avoid being overly arch-specific.
---
arch/x86/kernel/cpu/resctrl/internal.h | 3 ---
arch/x86/kernel/cpu/resctrl/monitor.c | 2 +-
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 5 ++---
include/linux/resctrl.h | 3 +++
4 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 6b076216911c..92a94939cf93 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -415,8 +415,6 @@ struct msr_param {
* @msr_update: Function pointer to update QOS MSRs
* @mon_scale: cqm counter * mon_scale = occupancy in bytes
* @mbm_width: Monitor width, to detect and correct for overflow.
- * @mbm_cfg_mask: Bandwidth sources that can be tracked when Bandwidth
- * Monitoring Event Configuration (BMEC) is supported.
* @cdp_enabled: CDP state of this resource
*
* Members of this structure are either private to the architecture
@@ -430,7 +428,6 @@ struct rdt_hw_resource {
void (*msr_update)(struct msr_param *m);
unsigned int mon_scale;
unsigned int mbm_width;
- unsigned int mbm_cfg_mask;
bool cdp_enabled;
};

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index ae8552ef98e6..175fd7dbf34f 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1256,7 +1256,7 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)

/* Detect list of bandwidth sources that can be tracked */
cpuid_count(0x80000020, 3, &eax, &ebx, &ecx, &edx);
- hw_res->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
+ r->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
}

r->mon_capable = true;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 304fdf199de7..0f839b5c59da 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1722,7 +1722,6 @@ static void mbm_config_write_domain(struct rdt_resource *r,

static int mon_config_write(struct rdt_resource *r, char *tok, u32 evtid)
{
- struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
char *dom_str = NULL, *id_str;
unsigned long dom_id, val;
struct rdt_mon_domain *d;
@@ -1749,9 +1748,9 @@ static int mon_config_write(struct rdt_resource *r, char *tok, u32 evtid)
}

/* Value from user cannot be more than the supported set of events */
- if ((val & hw_res->mbm_cfg_mask) != val) {
+ if ((val & r->mbm_cfg_mask) != val) {
rdt_last_cmd_printf("Invalid event configuration: max valid mask is 0x%02x\n",
- hw_res->mbm_cfg_mask);
+ r->mbm_cfg_mask);
return -EINVAL;
}

diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 0072c2e5947f..84588ab1994d 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -218,6 +218,8 @@ enum resctrl_schema_fmt {
* @name: Name to use in "schemata" file.
* @schema_fmt: Which format string and parser is used for this schema.
* @evt_list: List of monitoring events
+ * @mbm_cfg_mask: Bandwidth sources that can be tracked when Bandwidth
+ * Monitoring Event Configuration (BMEC) is supported.
* @cdp_capable: Is the CDP feature available on this resource
*/
struct rdt_resource {
@@ -234,6 +236,7 @@ struct rdt_resource {
char *name;
enum resctrl_schema_fmt schema_fmt;
struct list_head evt_list;
+ unsigned int mbm_cfg_mask;
bool cdp_capable;
};

--
2.39.2