[PATCH v3 32/38] x86/resctrl: Drop __init/__exit on assorted symbols

From: James Morse
Date: Fri Jun 14 2024 - 11:08:24 EST


Because ARM's MPAM controls are probed using MMIO, resctrl can't be
initialised until enough CPUs are online to have determined the
system-wide supported num_closid. Arm64 also supports 'late onlined
secondaries', where only a subset of CPUs are online during boot.

These two combine to mean the MPAM driver may not be able to initialise
resctrl until user-space has brought 'enough' CPUs online.

To allow MPAM to initialise resctrl after __init text has been free'd,
remove all the __init markings from resctrl.

The existing __exit markings cause these functions to be removed by the
linker as it has never been possible to build resctrl as a module. MPAM
has an error interrupt which causes the driver to reset and disable
itself. Remove the __exit markings to allow the MPAM driver to tear down
resctrl when an error occurs.

Signed-off-by: James Morse <james.morse@xxxxxxx>
Tested-by: Peter Newman <peternewman@xxxxxxxxxx>
Tested-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx>
---
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 8 ++++----
include/linux/resctrl.h | 4 ++--
2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index ddf3d0a26517..0936a4cddc9e 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2055,7 +2055,7 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
return NULL;
}

-static void __init thread_throttle_mode_init(void)
+static void thread_throttle_mode_init(void)
{
struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
struct rftype *rft;
@@ -4003,7 +4003,7 @@ static void rdtgroup_destroy_root(void)
rdtgroup_default.kn = NULL;
}

-static void __init rdtgroup_setup_default(void)
+static void rdtgroup_setup_default(void)
{
mutex_lock(&rdtgroup_mutex);

@@ -4196,7 +4196,7 @@ void resctrl_offline_cpu(unsigned int cpu)
*
* Return: 0 on success or -errno
*/
-int __init resctrl_init(void)
+int resctrl_init(void)
{
int ret = 0;

@@ -4253,7 +4253,7 @@ int __init resctrl_init(void)
return ret;
}

-void __exit resctrl_exit(void)
+void resctrl_exit(void)
{
rdtgroup_destroy_root();
debugfs_remove_recursive(debugfs_resctrl);
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 3fc5f760e041..31ae6d9a224e 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -452,7 +452,7 @@ void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_domain *d);
extern unsigned int resctrl_rmid_realloc_threshold;
extern unsigned int resctrl_rmid_realloc_limit;

-int __init resctrl_init(void);
-void __exit resctrl_exit(void);
+int resctrl_init(void);
+void resctrl_exit(void);

#endif /* _RESCTRL_H */
--
2.39.2