perf/amd/uncore: Allow the driver to be built as a module

Add support to build the AMD uncore driver as a module.

This is in order to facilitate development without having
to reboot the kernel in most cases.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210817221048.88063-8-kim.phillips@amd.com

diff --git a/arch/x86/events/Kconfig b/arch/x86/events/Kconfig
index 39d9ded..d6cdfe6 100644 (file)
--- a/arch/x86/events/Kconfig
+++ b/arch/x86/events/Kconfig
@@ -34,4 +34,14 @@ config PERF_EVENTS_AMD_POWER
          (CPUID Fn8000_0007_EDX[12]) interface to calculate the
          average power consumption on Family 15h processors.
 
+config PERF_EVENTS_AMD_UNCORE
+       tristate "AMD Uncore performance events"
+       depends on PERF_EVENTS && CPU_SUP_AMD
+       default y
+       help
+         Include support for AMD uncore performance events for use with
+         e.g., perf stat -e amd_l3/.../,amd_df/.../.
+
+         To compile this driver as a module, choose M here: the
+         module will be called 'amd-uncore'.
 endmenu

diff --git a/arch/x86/events/amd/Makefile b/arch/x86/events/amd/Makefile
index fe8795a..6cbe38d 100644 (file)
--- a/arch/x86/events/amd/Makefile
+++ b/arch/x86/events/amd/Makefile
@@ -1,8 +1,9 @@
 # SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_CPU_SUP_AMD)              += core.o uncore.o
+obj-$(CONFIG_CPU_SUP_AMD)              += core.o
 obj-$(CONFIG_PERF_EVENTS_AMD_POWER)    += power.o
 obj-$(CONFIG_X86_LOCAL_APIC)           += ibs.o
+obj-$(CONFIG_PERF_EVENTS_AMD_UNCORE)   += amd-uncore.o
+amd-uncore-objs                                := uncore.o
 ifdef CONFIG_AMD_IOMMU
 obj-$(CONFIG_CPU_SUP_AMD)              += iommu.o
 endif
-

diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
index a01f9f1..0d04414 100644 (file)
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -347,6 +347,7 @@ static struct pmu amd_nb_pmu = {
        .stop           = amd_uncore_stop,
        .read           = amd_uncore_read,
        .capabilities   = PERF_PMU_CAP_NO_EXCLUDE | PERF_PMU_CAP_NO_INTERRUPT,
+       .module         = THIS_MODULE,
 };
 
 static struct pmu amd_llc_pmu = {
@@ -360,6 +361,7 @@ static struct pmu amd_llc_pmu = {
        .stop           = amd_uncore_stop,
        .read           = amd_uncore_read,
        .capabilities   = PERF_PMU_CAP_NO_EXCLUDE | PERF_PMU_CAP_NO_INTERRUPT,
+       .module         = THIS_MODULE,
 };
 
 static struct amd_uncore *amd_uncore_alloc(unsigned int cpu)
@@ -665,4 +667,28 @@ fail_nb:
 
        return ret;
 }
-device_initcall(amd_uncore_init);
+
+static void __exit amd_uncore_exit(void)
+{
+       cpuhp_remove_state(CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE);
+       cpuhp_remove_state(CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING);
+       cpuhp_remove_state(CPUHP_PERF_X86_AMD_UNCORE_PREP);
+
+       if (boot_cpu_has(X86_FEATURE_PERFCTR_LLC)) {
+               perf_pmu_unregister(&amd_llc_pmu);
+               free_percpu(amd_uncore_llc);
+               amd_uncore_llc = NULL;
+       }
+
+       if (boot_cpu_has(X86_FEATURE_PERFCTR_NB)) {
+               perf_pmu_unregister(&amd_nb_pmu);
+               free_percpu(amd_uncore_nb);
+               amd_uncore_nb = NULL;
+       }
+}
+
+module_init(amd_uncore_init);
+module_exit(amd_uncore_exit);
+
+MODULE_DESCRIPTION("AMD Uncore Driver");
+MODULE_LICENSE("GPL v2");