[PATCH v1 23/31] x86/resctrl: Move thread_throttle_mode_init() to be managed by resctrl

James Morse
2024-03-21T16:52:44Z

thread_throttle_mode_init() is called from the architecture specific code
to make the 'thread_throttle_mode' file visible. The architecture specific
code has already set the membw.throttle_mode in the rdt_resource.

This doesn't need to be specific to the architecture, the throttle_mode
can be used by resctrl to determine if the 'thread_throttle_mode' file
should be visible.

Call thread_throttle_mode_init() from resctrl_setup(), check the
membw.throttle_mode on the MBA resource. This avoids publishing an
extra function between the architecture and filesystem code.

Signed-off-by: James Morse <james.morse@arm.com>
---
arch/x86/kernel/cpu/resctrl/core.c | 1 -
arch/x86/kernel/cpu/resctrl/internal.h | 1 -
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 9 ++++++++-
3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 824a94593e9d..7cdecd8ac00b 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -227,7 +227,6 @@ static bool __get_mem_config_intel(struct rdt_resource *r)
r->membw.throttle_mode = THREAD_THROTTLE_PER_THREAD;
else
r->membw.throttle_mode = THREAD_THROTTLE_MAX;
- thread_throttle_mode_init();

r->alloc_capable = true;

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index be4e8f31b127..e849d4407769 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -478,7 +478,6 @@ void cqm_handle_limbo(struct work_struct *work);
bool has_busy_rmid(struct rdt_domain *d);
void __check_limbo(struct rdt_domain *d, bool force_free);
void rdt_domain_reconfigure_cdp(struct rdt_resource *r);
-void __init thread_throttle_mode_init(void);
void mbm_config_rftype_init(const char *config);
void rdt_staged_configs_clear(void);
bool closid_allocated(unsigned int closid);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 9275d6f8a74e..702a94fad6db 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2069,10 +2069,15 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
return NULL;
}

-void __init thread_throttle_mode_init(void)
+static void __init thread_throttle_mode_init(void)
{
+ struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
struct rftype *rft;

+ if (!r->alloc_capable ||
+ r->membw.throttle_mode == THREAD_THROTTLE_UNDEFINED)
+ return;
+
rft = rdtgroup_get_rftype_by_name("thread_throttle_mode");
if (!rft)
return;
@@ -4194,6 +4199,8 @@ int __init resctrl_init(void)

rdtgroup_setup_default();

+ thread_throttle_mode_init();
+
ret = resctrl_mon_resource_init();
if (ret)
return ret;
--
2.39.2