releases/2.6.32.17/hwmon-coretemp-skip-duplicate-cpu-entries.patch

   1 From d883b9f0977269d519469da72faec6a7f72cb489 Mon Sep 17 00:00:00 2001
   2 From: Jean Delvare <khali@linux-fr.org>
   3 Date: Fri, 9 Jul 2010 16:22:49 +0200
   4 Subject: hwmon: (coretemp) Skip duplicate CPU entries
   5
   6 From: Jean Delvare <khali@linux-fr.org>
   7
   8 commit d883b9f0977269d519469da72faec6a7f72cb489 upstream.
   9
  10 On hyper-threaded CPUs, each core appears twice in the CPU list. Skip
  11 the second entry to avoid duplicate sensors.
  12
  13 Signed-off-by: Jean Delvare <khali@linux-fr.org>
  14 Acked-by: Huaxu Wan <huaxu.wan@intel.com>
  15 Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
  16
  17 ---
  18  drivers/hwmon/coretemp.c |   26 +++++++++++++++++++++++++-
  19  1 file changed, 25 insertions(+), 1 deletion(-)
  20
  21 --- a/drivers/hwmon/coretemp.c
  22 +++ b/drivers/hwmon/coretemp.c
  23 @@ -356,6 +356,10 @@ struct pdev_entry {
  24         struct list_head list;
  25         struct platform_device *pdev;
  26         unsigned int cpu;
  27 +#ifdef CONFIG_SMP
  28 +       u16 phys_proc_id;
  29 +       u16 cpu_core_id;
  30 +#endif
  31  };
  32
  33  static LIST_HEAD(pdev_list);
  34 @@ -366,6 +370,22 @@ static int __cpuinit coretemp_device_add
  35         int err;
  36         struct platform_device *pdev;
  37         struct pdev_entry *pdev_entry;
  38 +#ifdef CONFIG_SMP
  39 +       struct cpuinfo_x86 *c = &cpu_data(cpu);
  40 +#endif
  41 +
  42 +       mutex_lock(&pdev_list_mutex);
  43 +
  44 +#ifdef CONFIG_SMP
  45 +       /* Skip second HT entry of each core */
  46 +       list_for_each_entry(pdev_entry, &pdev_list, list) {
  47 +               if (c->phys_proc_id == pdev_entry->phys_proc_id &&
  48 +                   c->cpu_core_id == pdev_entry->cpu_core_id) {
  49 +                       err = 0;        /* Not an error */
  50 +                       goto exit;
  51 +               }
  52 +       }
  53 +#endif
  54
  55         pdev = platform_device_alloc(DRVNAME, cpu);
  56         if (!pdev) {
  57 @@ -389,7 +409,10 @@ static int __cpuinit coretemp_device_add
  58
  59         pdev_entry->pdev = pdev;
  60         pdev_entry->cpu = cpu;
  61 -       mutex_lock(&pdev_list_mutex);
  62 +#ifdef CONFIG_SMP
  63 +       pdev_entry->phys_proc_id = c->phys_proc_id;
  64 +       pdev_entry->cpu_core_id = c->cpu_core_id;
  65 +#endif
  66         list_add_tail(&pdev_entry->list, &pdev_list);
  67         mutex_unlock(&pdev_list_mutex);
  68
  69 @@ -400,6 +423,7 @@ exit_device_free:
  70  exit_device_put:
  71         platform_device_put(pdev);
  72  exit:
  73 +       mutex_unlock(&pdev_list_mutex);
  74         return err;
  75  }
  76