Re: [PATCH v4 03/11] perf/x86/rapl: Rename rapl_pmu variables

["Zhang, Rui" <rui.zhang@intel.com>]

On Thu, 2024-07-11 at 10:24 +0000, Dhananjay Ugwekar wrote:
> Rename struct rapl_pmu variables from "pmu" to "rapl_pmu", to
> avoid any confusion between the variables of two different
> structs pmu and rapl_pmu. As rapl_pmu also contains a pointer to
> struct pmu, which leads to situations in code like pmu->pmu,
> which is needlessly confusing. Above scenario is replaced with
> much more readable rapl_pmu->pmu with this change.
> 
> Also rename "pmus" member in rapl_pmus struct, for same reason.
> 
> No functional change.
> 
> Signed-off-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com>

Reviewed-by: Zhang Rui <rui.zhang@intel.com>

-rui
> ---
>  arch/x86/events/rapl.c | 104 ++++++++++++++++++++-------------------
> --
>  1 file changed, 52 insertions(+), 52 deletions(-)
> 
> diff --git a/arch/x86/events/rapl.c b/arch/x86/events/rapl.c
> index df71f38ad98d..e6162bd84f23 100644
> --- a/arch/x86/events/rapl.c
> +++ b/arch/x86/events/rapl.c
> @@ -123,7 +123,7 @@ struct rapl_pmu {
>  struct rapl_pmus {
>         struct pmu              pmu;
>         unsigned int            nr_rapl_pmu;
> -       struct rapl_pmu         *pmus[] __counted_by(nr_rapl_pmu);
> +       struct rapl_pmu         *rapl_pmu[]
> __counted_by(nr_rapl_pmu);
>  };
>  
>  enum rapl_unit_quirk {
> @@ -171,7 +171,7 @@ static inline struct rapl_pmu
> *cpu_to_rapl_pmu(unsigned int cpu)
>          * The unsigned check also catches the '-1' return value for
> non
>          * existent mappings in the topology map.
>          */
> -       return rapl_pmu_idx < rapl_pmus->nr_rapl_pmu ? rapl_pmus-
> >pmus[rapl_pmu_idx] : NULL;
> +       return rapl_pmu_idx < rapl_pmus->nr_rapl_pmu ? rapl_pmus-
> >rapl_pmu[rapl_pmu_idx] : NULL;
>  }
>  
>  static inline u64 rapl_read_counter(struct perf_event *event)
> @@ -235,34 +235,34 @@ static void rapl_start_hrtimer(struct rapl_pmu
> *pmu)
>  
>  static enum hrtimer_restart rapl_hrtimer_handle(struct hrtimer
> *hrtimer)
>  {
> -       struct rapl_pmu *pmu = container_of(hrtimer, struct rapl_pmu,
> hrtimer);
> +       struct rapl_pmu *rapl_pmu = container_of(hrtimer, struct
> rapl_pmu, hrtimer);
>         struct perf_event *event;
>         unsigned long flags;
>  
> -       if (!pmu->n_active)
> +       if (!rapl_pmu->n_active)
>                 return HRTIMER_NORESTART;
>  
> -       raw_spin_lock_irqsave(&pmu->lock, flags);
> +       raw_spin_lock_irqsave(&rapl_pmu->lock, flags);
>  
> -       list_for_each_entry(event, &pmu->active_list, active_entry)
> +       list_for_each_entry(event, &rapl_pmu->active_list,
> active_entry)
>                 rapl_event_update(event);
>  
> -       raw_spin_unlock_irqrestore(&pmu->lock, flags);
> +       raw_spin_unlock_irqrestore(&rapl_pmu->lock, flags);
>  
> -       hrtimer_forward_now(hrtimer, pmu->timer_interval);
> +       hrtimer_forward_now(hrtimer, rapl_pmu->timer_interval);
>  
>         return HRTIMER_RESTART;
>  }
>  
> -static void rapl_hrtimer_init(struct rapl_pmu *pmu)
> +static void rapl_hrtimer_init(struct rapl_pmu *rapl_pmu)
>  {
> -       struct hrtimer *hr = &pmu->hrtimer;
> +       struct hrtimer *hr = &rapl_pmu->hrtimer;
>  
>         hrtimer_init(hr, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
>         hr->function = rapl_hrtimer_handle;
>  }
>  
> -static void __rapl_pmu_event_start(struct rapl_pmu *pmu,
> +static void __rapl_pmu_event_start(struct rapl_pmu *rapl_pmu,
>                                    struct perf_event *event)
>  {
>         if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
> @@ -270,39 +270,39 @@ static void __rapl_pmu_event_start(struct
> rapl_pmu *pmu,
>  
>         event->hw.state = 0;
>  
> -       list_add_tail(&event->active_entry, &pmu->active_list);
> +       list_add_tail(&event->active_entry, &rapl_pmu->active_list);
>  
>         local64_set(&event->hw.prev_count, rapl_read_counter(event));
>  
> -       pmu->n_active++;
> -       if (pmu->n_active == 1)
> -               rapl_start_hrtimer(pmu);
> +       rapl_pmu->n_active++;
> +       if (rapl_pmu->n_active == 1)
> +               rapl_start_hrtimer(rapl_pmu);
>  }
>  
>  static void rapl_pmu_event_start(struct perf_event *event, int mode)
>  {
> -       struct rapl_pmu *pmu = event->pmu_private;
> +       struct rapl_pmu *rapl_pmu = event->pmu_private;
>         unsigned long flags;
>  
> -       raw_spin_lock_irqsave(&pmu->lock, flags);
> -       __rapl_pmu_event_start(pmu, event);
> -       raw_spin_unlock_irqrestore(&pmu->lock, flags);
> +       raw_spin_lock_irqsave(&rapl_pmu->lock, flags);
> +       __rapl_pmu_event_start(rapl_pmu, event);
> +       raw_spin_unlock_irqrestore(&rapl_pmu->lock, flags);
>  }
>  
>  static void rapl_pmu_event_stop(struct perf_event *event, int mode)
>  {
> -       struct rapl_pmu *pmu = event->pmu_private;
> +       struct rapl_pmu *rapl_pmu = event->pmu_private;
>         struct hw_perf_event *hwc = &event->hw;
>         unsigned long flags;
>  
> -       raw_spin_lock_irqsave(&pmu->lock, flags);
> +       raw_spin_lock_irqsave(&rapl_pmu->lock, flags);
>  
>         /* mark event as deactivated and stopped */
>         if (!(hwc->state & PERF_HES_STOPPED)) {
> -               WARN_ON_ONCE(pmu->n_active <= 0);
> -               pmu->n_active--;
> -               if (pmu->n_active == 0)
> -                       hrtimer_cancel(&pmu->hrtimer);
> +               WARN_ON_ONCE(rapl_pmu->n_active <= 0);
> +               rapl_pmu->n_active--;
> +               if (rapl_pmu->n_active == 0)
> +                       hrtimer_cancel(&rapl_pmu->hrtimer);
>  
>                 list_del(&event->active_entry);
>  
> @@ -320,23 +320,23 @@ static void rapl_pmu_event_stop(struct
> perf_event *event, int mode)
>                 hwc->state |= PERF_HES_UPTODATE;
>         }
>  
> -       raw_spin_unlock_irqrestore(&pmu->lock, flags);
> +       raw_spin_unlock_irqrestore(&rapl_pmu->lock, flags);
>  }
>  
>  static int rapl_pmu_event_add(struct perf_event *event, int mode)
>  {
> -       struct rapl_pmu *pmu = event->pmu_private;
> +       struct rapl_pmu *rapl_pmu = event->pmu_private;
>         struct hw_perf_event *hwc = &event->hw;
>         unsigned long flags;
>  
> -       raw_spin_lock_irqsave(&pmu->lock, flags);
> +       raw_spin_lock_irqsave(&rapl_pmu->lock, flags);
>  
>         hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
>  
>         if (mode & PERF_EF_START)
> -               __rapl_pmu_event_start(pmu, event);
> +               __rapl_pmu_event_start(rapl_pmu, event);
>  
> -       raw_spin_unlock_irqrestore(&pmu->lock, flags);
> +       raw_spin_unlock_irqrestore(&rapl_pmu->lock, flags);
>  
>         return 0;
>  }
> @@ -350,7 +350,7 @@ static int rapl_pmu_event_init(struct perf_event
> *event)
>  {
>         u64 cfg = event->attr.config & RAPL_EVENT_MASK;
>         int bit, ret = 0;
> -       struct rapl_pmu *pmu;
> +       struct rapl_pmu *rapl_pmu;
>  
>         /* only look at RAPL events */
>         if (event->attr.type != rapl_pmus->pmu.type)
> @@ -380,11 +380,11 @@ static int rapl_pmu_event_init(struct
> perf_event *event)
>                 return -EINVAL;
>  
>         /* must be done before validate_group */
> -       pmu = cpu_to_rapl_pmu(event->cpu);
> -       if (!pmu)
> +       rapl_pmu = cpu_to_rapl_pmu(event->cpu);
> +       if (!rapl_pmu)
>                 return -EINVAL;
> -       event->cpu = pmu->cpu;
> -       event->pmu_private = pmu;
> +       event->cpu = rapl_pmu->cpu;
> +       event->pmu_private = rapl_pmu;
>         event->hw.event_base = rapl_msrs[bit].msr;
>         event->hw.config = cfg;
>         event->hw.idx = bit;
> @@ -567,22 +567,22 @@ static struct perf_msr amd_rapl_msrs[] = {
>  static int rapl_cpu_offline(unsigned int cpu)
>  {
>         const struct cpumask *rapl_pmu_cpumask =
> get_rapl_pmu_cpumask(cpu);
> -       struct rapl_pmu *pmu = cpu_to_rapl_pmu(cpu);
> +       struct rapl_pmu *rapl_pmu = cpu_to_rapl_pmu(cpu);
>         int target;
>  
>         /* Check if exiting cpu is used for collecting rapl events */
>         if (!cpumask_test_and_clear_cpu(cpu, &rapl_cpu_mask))
>                 return 0;
>  
> -       pmu->cpu = -1;
> +       rapl_pmu->cpu = -1;
>         /* Find a new cpu to collect rapl events */
>         target = cpumask_any_but(rapl_pmu_cpumask, cpu);
>  
>         /* Migrate rapl events to the new target */
>         if (target < nr_cpu_ids) {
>                 cpumask_set_cpu(target, &rapl_cpu_mask);
> -               pmu->cpu = target;
> -               perf_pmu_migrate_context(pmu->pmu, cpu, target);
> +               rapl_pmu->cpu = target;
> +               perf_pmu_migrate_context(rapl_pmu->pmu, cpu, target);
>         }
>         return 0;
>  }
> @@ -591,21 +591,21 @@ static int rapl_cpu_online(unsigned int cpu)
>  {
>         unsigned int rapl_pmu_idx = get_rapl_pmu_idx(cpu);
>         const struct cpumask *rapl_pmu_cpumask =
> get_rapl_pmu_cpumask(cpu);
> -       struct rapl_pmu *pmu = cpu_to_rapl_pmu(cpu);
> +       struct rapl_pmu *rapl_pmu = cpu_to_rapl_pmu(cpu);
>         int target;
>  
> -       if (!pmu) {
> -               pmu = kzalloc_node(sizeof(*pmu), GFP_KERNEL,
> cpu_to_node(cpu));
> -               if (!pmu)
> +       if (!rapl_pmu) {
> +               rapl_pmu = kzalloc_node(sizeof(*rapl_pmu),
> GFP_KERNEL, cpu_to_node(cpu));
> +               if (!rapl_pmu)
>                         return -ENOMEM;
>  
> -               raw_spin_lock_init(&pmu->lock);
> -               INIT_LIST_HEAD(&pmu->active_list);
> -               pmu->pmu = &rapl_pmus->pmu;
> -               pmu->timer_interval = ms_to_ktime(rapl_timer_ms);
> -               rapl_hrtimer_init(pmu);
> +               raw_spin_lock_init(&rapl_pmu->lock);
> +               INIT_LIST_HEAD(&rapl_pmu->active_list);
> +               rapl_pmu->pmu = &rapl_pmus->pmu;
> +               rapl_pmu->timer_interval =
> ms_to_ktime(rapl_timer_ms);
> +               rapl_hrtimer_init(rapl_pmu);
>  
> -               rapl_pmus->pmus[rapl_pmu_idx] = pmu;
> +               rapl_pmus->rapl_pmu[rapl_pmu_idx] = rapl_pmu;
>         }
>  
>         /*
> @@ -617,7 +617,7 @@ static int rapl_cpu_online(unsigned int cpu)
>                 return 0;
>  
>         cpumask_set_cpu(cpu, &rapl_cpu_mask);
> -       pmu->cpu = cpu;
> +       rapl_pmu->cpu = cpu;
>         return 0;
>  }
>  
> @@ -686,7 +686,7 @@ static void cleanup_rapl_pmus(void)
>         int i;
>  
>         for (i = 0; i < rapl_pmus->nr_rapl_pmu; i++)
> -               kfree(rapl_pmus->pmus[i]);
> +               kfree(rapl_pmus->rapl_pmu[i]);
>         kfree(rapl_pmus);
>  }
>  
> @@ -706,7 +706,7 @@ static int __init init_rapl_pmus(void)
>         if (!rapl_pmu_is_pkg_scope())
>                 nr_rapl_pmu *= topology_max_dies_per_package();
>  
> -       rapl_pmus = kzalloc(struct_size(rapl_pmus, pmus,
> nr_rapl_pmu), GFP_KERNEL);
> +       rapl_pmus = kzalloc(struct_size(rapl_pmus, rapl_pmu,
> nr_rapl_pmu), GFP_KERNEL);
>         if (!rapl_pmus)
>                 return -ENOMEM;
>