[tip:smp/hotplug] mm/zsmalloc: Convert to hotplug state machine

[tip-bot for Sebastian Andrzej Siewior]

Commit-ID:  215c89d055e085c42cea4fd571a1d0db0b6d5648
Gitweb: http://git.kernel.org/tip/215c89d055e085c42cea4fd571a1d0db0b6d5648
Author: Sebastian Andrzej Siewior 
AuthorDate: Sun, 27 Nov 2016 00:13:38 +0100
Committer:  Thomas Gleixner 
CommitDate: Fri, 2 Dec 2016 00:52:36 +0100

mm/zsmalloc: Convert to hotplug state machine

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Sebastian Andrzej Siewior 
Cc: Sergey Senozhatsky 
Cc: linux...@kvack.org
Cc: Minchan Kim 
Cc: r...@linutronix.de
Cc: Nitin Gupta 
Link: http://lkml.kernel.org/r/20161126231350.10321-11-bige...@linutronix.de
Signed-off-by: Thomas Gleixner 

---
 include/linux/cpuhotplug.h |  1 +
 mm/zsmalloc.c  | 67 +-
 2 files changed, 14 insertions(+), 54 deletions(-)

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 4ebd1bc..9f29dd9 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -64,6 +64,7 @@ enum cpuhp_state {
CPUHP_NET_IUCV_PREPARE,
CPUHP_ARM_BL_PREPARE,
CPUHP_TRACE_RB_PREPARE,
+   CPUHP_MM_ZS_PREPARE,
CPUHP_TIMERS_DEAD,
CPUHP_NOTF_ERR_INJ_PREPARE,
CPUHP_MIPS_SOC_PREPARE,
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index b0bc023..9cc3c0b 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -1284,61 +1284,21 @@ out:
 
 #endif /* CONFIG_PGTABLE_MAPPING */
 
-static int zs_cpu_notifier(struct notifier_block *nb, unsigned long action,
-   void *pcpu)
+static int zs_cpu_prepare(unsigned int cpu)
 {
-   int ret, cpu = (long)pcpu;
struct mapping_area *area;
 
-   switch (action) {
-   case CPU_UP_PREPARE:
-   area = _cpu(zs_map_area, cpu);
-   ret = __zs_cpu_up(area);
-   if (ret)
-   return notifier_from_errno(ret);
-   break;
-   case CPU_DEAD:
-   case CPU_UP_CANCELED:
-   area = _cpu(zs_map_area, cpu);
-   __zs_cpu_down(area);
-   break;
-   }
-
-   return NOTIFY_OK;
+   area = _cpu(zs_map_area, cpu);
+   return __zs_cpu_up(area);
 }
 
-static struct notifier_block zs_cpu_nb = {
-   .notifier_call = zs_cpu_notifier
-};
-
-static int zs_register_cpu_notifier(void)
+static int zs_cpu_dead(unsigned int cpu)
 {
-   int cpu, uninitialized_var(ret);
-
-   cpu_notifier_register_begin();
-
-   __register_cpu_notifier(_cpu_nb);
-   for_each_online_cpu(cpu) {
-   ret = zs_cpu_notifier(NULL, CPU_UP_PREPARE, (void *)(long)cpu);
-   if (notifier_to_errno(ret))
-   break;
-   }
-
-   cpu_notifier_register_done();
-   return notifier_to_errno(ret);
-}
-
-static void zs_unregister_cpu_notifier(void)
-{
-   int cpu;
-
-   cpu_notifier_register_begin();
-
-   for_each_online_cpu(cpu)
-   zs_cpu_notifier(NULL, CPU_DEAD, (void *)(long)cpu);
-   __unregister_cpu_notifier(_cpu_nb);
+   struct mapping_area *area;
 
-   cpu_notifier_register_done();
+   area = _cpu(zs_map_area, cpu);
+   __zs_cpu_down(area);
+   return 0;
 }
 
 static void __init init_zs_size_classes(void)
@@ -2534,10 +2494,10 @@ static int __init zs_init(void)
if (ret)
goto out;
 
-   ret = zs_register_cpu_notifier();
-
+   ret = cpuhp_setup_state(CPUHP_MM_ZS_PREPARE, "mm/zsmalloc:prepare",
+   zs_cpu_prepare, zs_cpu_dead);
if (ret)
-   goto notifier_fail;
+   goto hp_setup_fail;
 
init_zs_size_classes();
 
@@ -2549,8 +2509,7 @@ static int __init zs_init(void)
 
return 0;
 
-notifier_fail:
-   zs_unregister_cpu_notifier();
+hp_setup_fail:
zsmalloc_unmount();
 out:
return ret;
@@ -2562,7 +2521,7 @@ static void __exit zs_exit(void)
zpool_unregister_driver(_zpool_driver);
 #endif
zsmalloc_unmount();
-   zs_unregister_cpu_notifier();
+   cpuhp_remove_state(CPUHP_MM_ZS_PREPARE);
 
zs_stat_exit();
 }

[tip:smp/hotplug] mm/zsmalloc: Convert to hotplug state machine

[tip-bot for Sebastian Andrzej Siewior]

Commit-ID:  215c89d055e085c42cea4fd571a1d0db0b6d5648
Gitweb: http://git.kernel.org/tip/215c89d055e085c42cea4fd571a1d0db0b6d5648
Author: Sebastian Andrzej Siewior 
AuthorDate: Sun, 27 Nov 2016 00:13:38 +0100
Committer:  Thomas Gleixner 
CommitDate: Fri, 2 Dec 2016 00:52:36 +0100

mm/zsmalloc: Convert to hotplug state machine

Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Sebastian Andrzej Siewior 
Cc: Sergey Senozhatsky 
Cc: linux...@kvack.org
Cc: Minchan Kim 
Cc: r...@linutronix.de
Cc: Nitin Gupta 
Link: http://lkml.kernel.org/r/20161126231350.10321-11-bige...@linutronix.de
Signed-off-by: Thomas Gleixner 

---
 include/linux/cpuhotplug.h |  1 +
 mm/zsmalloc.c  | 67 +-
 2 files changed, 14 insertions(+), 54 deletions(-)

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 4ebd1bc..9f29dd9 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -64,6 +64,7 @@ enum cpuhp_state {
CPUHP_NET_IUCV_PREPARE,
CPUHP_ARM_BL_PREPARE,
CPUHP_TRACE_RB_PREPARE,
+   CPUHP_MM_ZS_PREPARE,
CPUHP_TIMERS_DEAD,
CPUHP_NOTF_ERR_INJ_PREPARE,
CPUHP_MIPS_SOC_PREPARE,
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index b0bc023..9cc3c0b 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -1284,61 +1284,21 @@ out:
 
 #endif /* CONFIG_PGTABLE_MAPPING */
 
-static int zs_cpu_notifier(struct notifier_block *nb, unsigned long action,
-   void *pcpu)
+static int zs_cpu_prepare(unsigned int cpu)
 {
-   int ret, cpu = (long)pcpu;
struct mapping_area *area;
 
-   switch (action) {
-   case CPU_UP_PREPARE:
-   area = _cpu(zs_map_area, cpu);
-   ret = __zs_cpu_up(area);
-   if (ret)
-   return notifier_from_errno(ret);
-   break;
-   case CPU_DEAD:
-   case CPU_UP_CANCELED:
-   area = _cpu(zs_map_area, cpu);
-   __zs_cpu_down(area);
-   break;
-   }
-
-   return NOTIFY_OK;
+   area = _cpu(zs_map_area, cpu);
+   return __zs_cpu_up(area);
 }
 
-static struct notifier_block zs_cpu_nb = {
-   .notifier_call = zs_cpu_notifier
-};
-
-static int zs_register_cpu_notifier(void)
+static int zs_cpu_dead(unsigned int cpu)
 {
-   int cpu, uninitialized_var(ret);
-
-   cpu_notifier_register_begin();
-
-   __register_cpu_notifier(_cpu_nb);
-   for_each_online_cpu(cpu) {
-   ret = zs_cpu_notifier(NULL, CPU_UP_PREPARE, (void *)(long)cpu);
-   if (notifier_to_errno(ret))
-   break;
-   }
-
-   cpu_notifier_register_done();
-   return notifier_to_errno(ret);
-}
-
-static void zs_unregister_cpu_notifier(void)
-{
-   int cpu;
-
-   cpu_notifier_register_begin();
-
-   for_each_online_cpu(cpu)
-   zs_cpu_notifier(NULL, CPU_DEAD, (void *)(long)cpu);
-   __unregister_cpu_notifier(_cpu_nb);
+   struct mapping_area *area;
 
-   cpu_notifier_register_done();
+   area = _cpu(zs_map_area, cpu);
+   __zs_cpu_down(area);
+   return 0;
 }
 
 static void __init init_zs_size_classes(void)
@@ -2534,10 +2494,10 @@ static int __init zs_init(void)
if (ret)
goto out;
 
-   ret = zs_register_cpu_notifier();
-
+   ret = cpuhp_setup_state(CPUHP_MM_ZS_PREPARE, "mm/zsmalloc:prepare",
+   zs_cpu_prepare, zs_cpu_dead);
if (ret)
-   goto notifier_fail;
+   goto hp_setup_fail;
 
init_zs_size_classes();
 
@@ -2549,8 +2509,7 @@ static int __init zs_init(void)
 
return 0;
 
-notifier_fail:
-   zs_unregister_cpu_notifier();
+hp_setup_fail:
zsmalloc_unmount();
 out:
return ret;
@@ -2562,7 +2521,7 @@ static void __exit zs_exit(void)
zpool_unregister_driver(_zpool_driver);
 #endif
zsmalloc_unmount();
-   zs_unregister_cpu_notifier();
+   cpuhp_remove_state(CPUHP_MM_ZS_PREPARE);
 
zs_stat_exit();
 }