x86/events/amd/iommu: Fix sysfs perf attribute groups

Introduce static amd_iommu_attr_groups to simplify the
sysfs attributes initialization code.

Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jörg Rödel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: iommu@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/1487926102-13073-9-git-send-email-Suravee.Suthikulpanit@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/events/amd/iommu.c b/arch/x86/events/amd/iommu.c
index 88fbc80..7ac8138 100644 (file)
--- a/arch/x86/events/amd/iommu.c
+++ b/arch/x86/events/amd/iommu.c
@@ -43,14 +43,8 @@ struct perf_amd_iommu {
        u8 max_counters;
        u64 cntr_assign_mask;
        raw_spinlock_t lock;
-       const struct attribute_group *attr_groups[4];
 };
 
-#define format_group   attr_groups[0]
-#define cpumask_group  attr_groups[1]
-#define events_group   attr_groups[2]
-#define null_group     attr_groups[3]
-
 /*---------------------------------------------
  * sysfs format attributes
  *---------------------------------------------*/
@@ -81,6 +75,10 @@ static struct attribute_group amd_iommu_format_group = {
 /*---------------------------------------------
  * sysfs events attributes
  *---------------------------------------------*/
+static struct attribute_group amd_iommu_events_group = {
+       .name = "events",
+};
+
 struct amd_iommu_event_desc {
        struct kobj_attribute attr;
        const char *event;
@@ -384,76 +382,60 @@ static void perf_iommu_del(struct perf_event *event, int flags)
        perf_event_update_userpage(event);
 }
 
-static __init int _init_events_attrs(struct perf_amd_iommu *perf_iommu)
+static __init int _init_events_attrs(void)
 {
-       struct attribute **attrs;
-       struct attribute_group *attr_group;
        int i = 0, j;
+       struct attribute **attrs;
 
        while (amd_iommu_v2_event_descs[i].attr.attr.name)
                i++;
 
-       attr_group = kzalloc(sizeof(struct attribute *)
-               * (i + 1) + sizeof(*attr_group), GFP_KERNEL);
-       if (!attr_group)
+       attrs = kzalloc(sizeof(struct attribute **) * (i + 1), GFP_KERNEL);
+       if (!attrs)
                return -ENOMEM;
 
-       attrs = (struct attribute **)(attr_group + 1);
        for (j = 0; j < i; j++)
                attrs[j] = &amd_iommu_v2_event_descs[j].attr.attr;
 
-       attr_group->name = "events";
-       attr_group->attrs = attrs;
-       perf_iommu->events_group = attr_group;
-
+       amd_iommu_events_group.attrs = attrs;
        return 0;
 }
 
 static __init void amd_iommu_pc_exit(void)
 {
-       if (__perf_iommu.events_group != NULL) {
-               kfree(__perf_iommu.events_group);
-               __perf_iommu.events_group = NULL;
-       }
+       kfree(amd_iommu_events_group.attrs);
 }
 
-static __init int _init_perf_amd_iommu(
-       struct perf_amd_iommu *perf_iommu, char *name)
+const struct attribute_group *amd_iommu_attr_groups[] = {
+       &amd_iommu_format_group,
+       &amd_iommu_cpumask_group,
+       &amd_iommu_events_group,
+       NULL,
+};
+
+static __init int
+_init_perf_amd_iommu(struct perf_amd_iommu *perf_iommu, char *name)
 {
        int ret;
 
        raw_spin_lock_init(&perf_iommu->lock);
 
-       perf_iommu->format_group = &amd_iommu_format_group;
-
        /* Init cpumask attributes to only core 0 */
        cpumask_set_cpu(0, &iommu_cpumask);
-       perf_iommu->cpumask_group = &amd_iommu_cpumask_group;
-
-       ret = _init_events_attrs(perf_iommu);
-       if (ret) {
-               pr_err("Error initializing AMD IOMMU perf events.\n");
-               return ret;
-       }
 
        perf_iommu->max_banks    = amd_iommu_pc_get_max_banks(0);
        perf_iommu->max_counters = amd_iommu_pc_get_max_counters(0);
        if (!perf_iommu->max_banks || !perf_iommu->max_counters)
                return -EINVAL;
 
-       perf_iommu->null_group = NULL;
-       perf_iommu->pmu.attr_groups = perf_iommu->attr_groups;
-
+       perf_iommu->pmu.attr_groups = amd_iommu_attr_groups;
        ret = perf_pmu_register(&perf_iommu->pmu, name, -1);
-       if (ret) {
+       if (ret)
                pr_err("Error initializing AMD IOMMU perf counters.\n");
-               amd_iommu_pc_exit();
-       } else {
+       else
                pr_info("Detected AMD IOMMU (%d banks, %d counters/bank).\n",
                        amd_iommu_pc_get_max_banks(0),
                        amd_iommu_pc_get_max_counters(0));
-       }
-
        return ret;
 }
 
@@ -467,24 +449,25 @@ static struct perf_amd_iommu __perf_iommu = {
                .stop           = perf_iommu_stop,
                .read           = perf_iommu_read,
        },
-       .max_banks              = 0x00,
-       .max_counters           = 0x00,
-       .cntr_assign_mask       = 0ULL,
-       .format_group           = NULL,
-       .cpumask_group          = NULL,
-       .events_group           = NULL,
-       .null_group             = NULL,
 };
 
 static __init int amd_iommu_pc_init(void)
 {
+       int ret;
+
        /* Make sure the IOMMU PC resource is available */
        if (!amd_iommu_pc_supported())
                return -ENODEV;
 
-       _init_perf_amd_iommu(&__perf_iommu, "amd_iommu");
+       ret = _init_events_attrs();
+       if (ret)
+               return ret;
 
-       return 0;
+       ret = _init_perf_amd_iommu(&__perf_iommu, "amd_iommu");
+       if (ret)
+               amd_iommu_pc_exit();
+
+       return ret;
 }
 
 device_initcall(amd_iommu_pc_init);