perf/x86/intel/uncore: Make PCI and MSR uncore independent

Andi wanted to do this before, but the patch fell down the cracks. Implement
it with the proper error handling.

Requested-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Harish Chegondi <harish.chegondi@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20160222221011.799159968@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/events/intel/uncore.c b/arch/x86/events/intel/uncore.c
index 5ad8e52cbc369cd0d9fb881a424804dbde100c45..7012d18bb293073e7cf0021cab79c50e3e42289c 100644 (file)
--- a/arch/x86/events/intel/uncore.c
+++ b/arch/x86/events/intel/uncore.c
@@ -1023,7 +1023,7 @@ static int __init uncore_pci_init(void)
                ret = skl_uncore_pci_init();
                break;
        default:
-               return 0;
+               return -ENODEV;
        }
 
        if (ret)
@@ -1324,7 +1324,7 @@ static int __init uncore_cpu_init(void)
                knl_uncore_cpu_init();
                break;
        default:
-               return 0;
+               return -ENODEV;
        }
 
        ret = uncore_types_init(uncore_msr_uncores, true);
@@ -1349,7 +1349,7 @@ static void __init uncore_cpu_setup(void *dummy)
 /* Lazy to avoid allocation of a few bytes for the normal case */
 static __initdata DECLARE_BITMAP(packages, MAX_LOCAL_APIC);
 
-static int __init uncore_cpumask_init(void)
+static int __init uncore_cpumask_init(bool msr)
 {
        unsigned int cpu;
 
@@ -1360,12 +1360,15 @@ static int __init uncore_cpumask_init(void)
                if (test_and_set_bit(pkg, packages))
                        continue;
                /*
-                * The first online cpu of each package takes the refcounts
-                * for all other online cpus in that package.
+                * The first online cpu of each package allocates and takes
+                * the refcounts for all other online cpus in that package.
+                * If msrs are not enabled no allocation is required.
                 */
-               ret = uncore_cpu_prepare(cpu);
-               if (ret)
-                       return ret;
+               if (msr) {
+                       ret = uncore_cpu_prepare(cpu);
+                       if (ret)
+                               return ret;
+               }
                uncore_event_init_cpu(cpu);
                smp_call_function_single(cpu, uncore_cpu_setup, NULL, 1);
        }
@@ -1375,7 +1378,7 @@ static int __init uncore_cpumask_init(void)
 
 static int __init intel_uncore_init(void)
 {
-       int ret;
+       int pret, cret, ret;
 
        if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
                return -ENODEV;
@@ -1385,15 +1388,14 @@ static int __init intel_uncore_init(void)
 
        max_packages = topology_max_packages();
 
-       ret = uncore_pci_init();
-       if (ret)
-               return ret;
-       ret = uncore_cpu_init();
-       if (ret)
-               goto err;
+       pret = uncore_pci_init();
+       cret = uncore_cpu_init();
+
+       if (cret && pret)
+               return -ENODEV;
 
        cpu_notifier_register_begin();
-       ret = uncore_cpumask_init();
+       ret = uncore_cpumask_init(!cret);
        if (ret)
                goto err;
        cpu_notifier_register_done();