The following commit has been merged into the x86/cache branch of tip:
Commit-ID: 6c2282d42cb37f081587412f77340138b1df265e
Gitweb: https://git.kernel.org/tip/6c2282d42cb37f081587412f77340138b1df265e
Author: James Morse <james.morse@xxxxxxx>
AuthorDate: Tue, 11 Mar 2025 18:37:13
Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Wed, 12 Mar 2025 12:24:46 +01:00
x86/resctrl: Handle throttle_mode for SMBA resources
Now that the visibility of throttle_mode is being managed by resctrl, it
should consider resources other than MBA that may have a throttle_mode. SMBA
is one such resource.
Extend thread_throttle_mode_init() to check SMBA for a throttle_mode.
Adding support for multiple resources means it is possible for a platform with
both MBA and SMBA, but an undefined throttle_mode on one of them to make the
file visible.
Add the 'undefined' case to rdt_thread_throttle_mode_show().
Signed-off-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Reviewed-by: Fenghua Yu <fenghuay@xxxxxxxxxx>
Reviewed-by: Babu Moger <babu.moger@xxxxxxx>
Reviewed-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx>
Tested-by: Peter Newman <peternewman@xxxxxxxxxx>
Tested-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx>
Tested-by: Amit Singh Tomar <amitsinght@xxxxxxxxxxx> # arm64
Tested-by: Shanker Donthineni <sdonthineni@xxxxxxxxxx> # arm64
Tested-by: Babu Moger <babu.moger@xxxxxxx>
Link: https://lore.kernel.org/r/20250311183715.16445-29-james.morse@xxxxxxx
---
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 33 ++++++++++++++++++++-----
1 file changed, 27 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 58feba3..5fc60c9 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1188,10 +1188,19 @@ static int rdt_thread_throttle_mode_show(struct kernfs_open_file *of,
struct resctrl_schema *s = of->kn->parent->priv;
struct rdt_resource *r = s->res;
- if (r->membw.throttle_mode == THREAD_THROTTLE_PER_THREAD)
+ switch (r->membw.throttle_mode) {
+ case THREAD_THROTTLE_PER_THREAD:
seq_puts(seq, "per-thread\n");
- else
+ return 0;
+ case THREAD_THROTTLE_MAX:
seq_puts(seq, "max\n");
+ return 0;
+ case THREAD_THROTTLE_UNDEFINED:
+ seq_puts(seq, "undefined\n");
+ return 0;
+ }
+
+ WARN_ON_ONCE(1);
return 0;
}
@@ -2066,12 +2075,24 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
static void thread_throttle_mode_init(void)
{
- struct rdt_resource *r_mba;
+ enum membw_throttle_mode throttle_mode = THREAD_THROTTLE_UNDEFINED;
+ struct rdt_resource *r_mba, *r_smba;
r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
- if (r_mba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
- resctrl_file_fflags_init("thread_throttle_mode",
- RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
+ if (r_mba->alloc_capable &&
+ r_mba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
+ throttle_mode = r_mba->membw.throttle_mode;
+
+ r_smba = resctrl_arch_get_resource(RDT_RESOURCE_SMBA);
+ if (r_smba->alloc_capable &&
+ r_smba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
+ throttle_mode = r_smba->membw.throttle_mode;
+
+ if (throttle_mode == THREAD_THROTTLE_UNDEFINED)
+ return;
+
+ resctrl_file_fflags_init("thread_throttle_mode",
+ RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
}
void resctrl_file_fflags_init(const char *config, unsigned long fflags)
|