[PATCH] hotplug CPU: clean up hotcpu_notifier() use
There was lots of #ifdef noise in the kernel due to hotcpu_notifier(fn,
prio) not correctly marking 'fn' as used in the !HOTPLUG_CPU case, and thus
generating compiler warnings of unused symbols, hence forcing people to add
#ifdefs.
the compiler can skip truly unused functions just fine:
text data bss dec hex filename
1624412 728710 3674856 6027978 5bfaca vmlinux.before
1624412 728710 3674856 6027978 5bfaca vmlinux.after
[akpm@osdl.org: topology.c fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/i386/kernel/cpu/mcheck/therm_throt.c b/arch/i386/kernel/cpu/mcheck/therm_throt.c
index bad8b44..065005c 100644
--- a/arch/i386/kernel/cpu/mcheck/therm_throt.c
+++ b/arch/i386/kernel/cpu/mcheck/therm_throt.c
@@ -116,7 +116,6 @@
return sysfs_create_group(&sys_dev->kobj, &thermal_throttle_attr_group);
}
-#ifdef CONFIG_HOTPLUG_CPU
static __cpuinit void thermal_throttle_remove_dev(struct sys_device *sys_dev)
{
return sysfs_remove_group(&sys_dev->kobj, &thermal_throttle_attr_group);
@@ -153,7 +152,6 @@
{
.notifier_call = thermal_throttle_cpu_callback,
};
-#endif /* CONFIG_HOTPLUG_CPU */
static __init int thermal_throttle_init_device(void)
{
diff --git a/arch/i386/kernel/cpuid.c b/arch/i386/kernel/cpuid.c
index ab0c327..23b2cc7 100644
--- a/arch/i386/kernel/cpuid.c
+++ b/arch/i386/kernel/cpuid.c
@@ -167,7 +167,6 @@
return err;
}
-#ifdef CONFIG_HOTPLUG_CPU
static int cpuid_class_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
@@ -187,7 +186,6 @@
{
.notifier_call = cpuid_class_cpu_callback,
};
-#endif /* !CONFIG_HOTPLUG_CPU */
static int __init cpuid_init(void)
{
diff --git a/arch/i386/kernel/microcode.c b/arch/i386/kernel/microcode.c
index 23f5984..9723466 100644
--- a/arch/i386/kernel/microcode.c
+++ b/arch/i386/kernel/microcode.c
@@ -703,7 +703,6 @@
.resume = mc_sysdev_resume,
};
-#ifdef CONFIG_HOTPLUG_CPU
static __cpuinit int
mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
{
@@ -726,7 +725,6 @@
static struct notifier_block mc_cpu_notifier = {
.notifier_call = mc_cpu_callback,
};
-#endif
static int __init microcode_init (void)
{
diff --git a/arch/i386/kernel/msr.c b/arch/i386/kernel/msr.c
index a773f77..7763c67 100644
--- a/arch/i386/kernel/msr.c
+++ b/arch/i386/kernel/msr.c
@@ -250,7 +250,6 @@
return err;
}
-#ifdef CONFIG_HOTPLUG_CPU
static int msr_class_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
@@ -271,7 +270,6 @@
{
.notifier_call = msr_class_cpu_callback,
};
-#endif
static int __init msr_init(void)
{
diff --git a/arch/ia64/kernel/palinfo.c b/arch/ia64/kernel/palinfo.c
index 0b546e2..c4c10a0 100644
--- a/arch/ia64/kernel/palinfo.c
+++ b/arch/ia64/kernel/palinfo.c
@@ -952,7 +952,6 @@
}
}
-#ifdef CONFIG_HOTPLUG_CPU
static int palinfo_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
@@ -974,7 +973,6 @@
.notifier_call = palinfo_cpu_callback,
.priority = 0,
};
-#endif
static int __init
palinfo_init(void)
diff --git a/arch/ia64/kernel/salinfo.c b/arch/ia64/kernel/salinfo.c
index e63b8ca..fd607ca 100644
--- a/arch/ia64/kernel/salinfo.c
+++ b/arch/ia64/kernel/salinfo.c
@@ -575,7 +575,6 @@
.write = salinfo_log_write,
};
-#ifdef CONFIG_HOTPLUG_CPU
static int __devinit
salinfo_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
{
@@ -620,7 +619,6 @@
.notifier_call = salinfo_cpu_callback,
.priority = 0,
};
-#endif /* CONFIG_HOTPLUG_CPU */
static int __init
salinfo_init(void)
diff --git a/arch/s390/appldata/appldata_base.c b/arch/s390/appldata/appldata_base.c
index 67d5cf9..b8c2372 100644
--- a/arch/s390/appldata/appldata_base.c
+++ b/arch/s390/appldata/appldata_base.c
@@ -561,7 +561,6 @@
spin_unlock(&appldata_timer_lock);
}
-#ifdef CONFIG_HOTPLUG_CPU
static int __cpuinit
appldata_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
@@ -582,7 +581,6 @@
static struct notifier_block appldata_nb = {
.notifier_call = appldata_cpu_notify,
};
-#endif
/*
* appldata_init()
diff --git a/arch/x86_64/kernel/mce.c b/arch/x86_64/kernel/mce.c
index c7587fc..bc863c4 100644
--- a/arch/x86_64/kernel/mce.c
+++ b/arch/x86_64/kernel/mce.c
@@ -641,7 +641,6 @@
return err;
}
-#ifdef CONFIG_HOTPLUG_CPU
static void mce_remove_device(unsigned int cpu)
{
int i;
@@ -674,7 +673,6 @@
static struct notifier_block mce_cpu_notifier = {
.notifier_call = mce_cpu_callback,
};
-#endif
static __init int mce_init_device(void)
{
diff --git a/arch/x86_64/kernel/mce_amd.c b/arch/x86_64/kernel/mce_amd.c
index 883fe74..fa09deb 100644
--- a/arch/x86_64/kernel/mce_amd.c
+++ b/arch/x86_64/kernel/mce_amd.c
@@ -551,7 +551,6 @@
return err;
}
-#ifdef CONFIG_HOTPLUG_CPU
/*
* let's be hotplug friendly.
* in case of multiple core processors, the first core always takes ownership
@@ -594,12 +593,14 @@
sprintf(name, "threshold_bank%i", bank);
+#ifdef CONFIG_SMP
/* sibling symlink */
if (shared_bank[bank] && b->blocks->cpu != cpu) {
sysfs_remove_link(&per_cpu(device_mce, cpu).kobj, name);
per_cpu(threshold_banks, cpu)[bank] = NULL;
return;
}
+#endif
/* remove all sibling symlinks before unregistering */
for_each_cpu_mask(i, b->cpus) {
@@ -656,7 +657,6 @@
static struct notifier_block threshold_cpu_notifier = {
.notifier_call = threshold_cpu_callback,
};
-#endif /* CONFIG_HOTPLUG_CPU */
static __init int threshold_init_device(void)
{
diff --git a/arch/x86_64/kernel/vsyscall.c b/arch/x86_64/kernel/vsyscall.c
index 630036c..3785e49 100644
--- a/arch/x86_64/kernel/vsyscall.c
+++ b/arch/x86_64/kernel/vsyscall.c
@@ -275,7 +275,6 @@
vsyscall_set_cpu(raw_smp_processor_id());
}
-#ifdef CONFIG_HOTPLUG_CPU
static int __cpuinit
cpu_vsyscall_notifier(struct notifier_block *n, unsigned long action, void *arg)
{
@@ -284,7 +283,6 @@
smp_call_function_single(cpu, cpu_vsyscall_init, NULL, 0, 1);
return NOTIFY_DONE;
}
-#endif
static void __init map_vsyscall(void)
{
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index a4ff327..31512cd 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -3459,8 +3459,6 @@
}
}
-#ifdef CONFIG_HOTPLUG_CPU
-
static int blk_cpu_notify(struct notifier_block *self, unsigned long action,
void *hcpu)
{
@@ -3486,8 +3484,6 @@
.notifier_call = blk_cpu_notify,
};
-#endif /* CONFIG_HOTPLUG_CPU */
-
/**
* blk_complete_request - end I/O on a request
* @req: the request being processed
diff --git a/drivers/base/topology.c b/drivers/base/topology.c
index 3d12b85..067a9e8 100644
--- a/drivers/base/topology.c
+++ b/drivers/base/topology.c
@@ -108,7 +108,6 @@
return rc;
}
-#ifdef CONFIG_HOTPLUG_CPU
static void __cpuinit topology_remove_dev(unsigned int cpu)
{
struct sys_device *sys_dev = get_cpu_sysdev(cpu);
@@ -136,7 +135,6 @@
}
return rc ? NOTIFY_BAD : NOTIFY_OK;
}
-#endif
static int __cpuinit topology_sysfs_init(void)
{
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 7a7c6e6..47ab42d 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1537,7 +1537,6 @@
}
EXPORT_SYMBOL(cpufreq_update_policy);
-#ifdef CONFIG_HOTPLUG_CPU
static int cpufreq_cpu_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
@@ -1577,7 +1576,6 @@
{
.notifier_call = cpufreq_cpu_callback,
};
-#endif /* CONFIG_HOTPLUG_CPU */
/*********************************************************************
* REGISTER / UNREGISTER CPUFREQ DRIVER *
diff --git a/fs/buffer.c b/fs/buffer.c
index a8ca0ac..517860f 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2972,7 +2972,6 @@
}
}
-#ifdef CONFIG_HOTPLUG_CPU
static void buffer_exit_cpu(int cpu)
{
int i;
@@ -2994,7 +2993,6 @@
buffer_exit_cpu((unsigned long)hcpu);
return NOTIFY_OK;
}
-#endif /* CONFIG_HOTPLUG_CPU */
void __init buffer_init(void)
{
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index f02d71b..71dc6ba 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -89,9 +89,9 @@
#define lock_cpu_hotplug() do { } while (0)
#define unlock_cpu_hotplug() do { } while (0)
#define lock_cpu_hotplug_interruptible() 0
-#define hotcpu_notifier(fn, pri) do { } while (0)
-#define register_hotcpu_notifier(nb) do { } while (0)
-#define unregister_hotcpu_notifier(nb) do { } while (0)
+#define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0)
+#define register_hotcpu_notifier(nb) do { (void)(nb); } while (0)
+#define unregister_hotcpu_notifier(nb) do { (void)(nb); } while (0)
/* CPUs don't go offline once they're online w/o CONFIG_HOTPLUG_CPU */
static inline int cpu_is_offline(int cpu) { return 0; }
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index bd1e89c4..9b62b4c 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -2044,7 +2044,6 @@
return err;
}
-#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_MEMORY_HOTPLUG)
/*
* If common_cpu_mem_hotplug_unplug(), below, unplugs any CPUs
* or memory nodes, we need to walk over the cpuset hierarchy,
@@ -2108,9 +2107,7 @@
mutex_unlock(&callback_mutex);
mutex_unlock(&manage_mutex);
}
-#endif
-#ifdef CONFIG_HOTPLUG_CPU
/*
* The top_cpuset tracks what CPUs and Memory Nodes are online,
* period. This is necessary in order to make cpusets transparent
@@ -2127,7 +2124,6 @@
common_cpu_mem_hotplug_unplug();
return 0;
}
-#endif
#ifdef CONFIG_MEMORY_HOTPLUG
/*
diff --git a/kernel/profile.c b/kernel/profile.c
index 04fd84e..0961d93 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -319,7 +319,6 @@
put_cpu();
}
-#ifdef CONFIG_HOTPLUG_CPU
static int __devinit profile_cpu_callback(struct notifier_block *info,
unsigned long action, void *__cpu)
{
@@ -372,10 +371,10 @@
}
return NOTIFY_OK;
}
-#endif /* CONFIG_HOTPLUG_CPU */
#else /* !CONFIG_SMP */
#define profile_flip_buffers() do { } while (0)
#define profile_discard_flip_buffers() do { } while (0)
+#define profile_cpu_callback NULL
void profile_hits(int type, void *__pc, unsigned int nr_hits)
{
diff --git a/kernel/sched.c b/kernel/sched.c
index 75a005e..c83f531 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -6740,8 +6740,6 @@
sched_smt_power_savings_store);
#endif
-
-#ifdef CONFIG_HOTPLUG_CPU
/*
* Force a reinitialization of the sched domains hierarchy. The domains
* and groups cannot be updated in place without racing with the balancing
@@ -6774,7 +6772,6 @@
return NOTIFY_OK;
}
-#endif
void __init sched_init_smp(void)
{
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 5484d6e..c525731 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -655,7 +655,6 @@
}
-#ifdef CONFIG_HOTPLUG_CPU
/* Take the work from this (downed) CPU. */
static void take_over_work(struct workqueue_struct *wq, unsigned int cpu)
{
@@ -738,7 +737,6 @@
return NOTIFY_OK;
}
-#endif
void init_workqueues(void)
{
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index e2cefab..d69ddbe 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -996,7 +996,6 @@
height_to_maxindex[i] = __maxindex(i);
}
-#ifdef CONFIG_HOTPLUG_CPU
static int radix_tree_callback(struct notifier_block *nfb,
unsigned long action,
void *hcpu)
@@ -1016,7 +1015,6 @@
}
return NOTIFY_OK;
}
-#endif /* CONFIG_HOTPLUG_CPU */
void __init radix_tree_init(void)
{
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2273952..27ec7a1 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -701,7 +701,6 @@
}
#endif
-#if defined(CONFIG_PM) || defined(CONFIG_HOTPLUG_CPU)
static void __drain_pages(unsigned int cpu)
{
unsigned long flags;
@@ -723,7 +722,6 @@
}
}
}
-#endif /* CONFIG_PM || CONFIG_HOTPLUG_CPU */
#ifdef CONFIG_PM
@@ -2907,7 +2905,6 @@
__pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
}
-#ifdef CONFIG_HOTPLUG_CPU
static int page_alloc_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
@@ -2922,7 +2919,6 @@
}
return NOTIFY_OK;
}
-#endif /* CONFIG_HOTPLUG_CPU */
void __init page_alloc_init(void)
{
diff --git a/mm/swap.c b/mm/swap.c
index 017e72c..2ed7be3 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -514,5 +514,7 @@
* Right now other parts of the system means that we
* _really_ don't want to cluster much more
*/
+#ifdef CONFIG_HOTPLUG_CPU
hotcpu_notifier(cpu_swap_callback, 0);
+#endif
}
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f6616e8..093f5fe 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1513,7 +1513,6 @@
}
#endif
-#ifdef CONFIG_HOTPLUG_CPU
/* It's optimal to keep kswapds on the same CPUs as their memory, but
not required for correctness. So if the last cpu in a node goes
away, we get changed to run anywhere: as the first one comes back,
@@ -1534,7 +1533,6 @@
}
return NOTIFY_OK;
}
-#endif /* CONFIG_HOTPLUG_CPU */
/*
* This kswapd start function will be called by init and node-hot-add.
diff --git a/net/core/dev.c b/net/core/dev.c
index 59d058a..e660cb5 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3340,7 +3340,6 @@
EXPORT_SYMBOL(unregister_netdev);
-#ifdef CONFIG_HOTPLUG_CPU
static int dev_cpu_callback(struct notifier_block *nfb,
unsigned long action,
void *ocpu)
@@ -3384,7 +3383,6 @@
return NOTIFY_OK;
}
-#endif /* CONFIG_HOTPLUG_CPU */
#ifdef CONFIG_NET_DMA
/**
diff --git a/net/core/flow.c b/net/core/flow.c
index 104c25d..d137f97 100644
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -340,7 +340,6 @@
tasklet_init(tasklet, flow_cache_flush_tasklet, 0);
}
-#ifdef CONFIG_HOTPLUG_CPU
static int flow_cache_cpu(struct notifier_block *nfb,
unsigned long action,
void *hcpu)
@@ -349,7 +348,6 @@
__flow_cache_shrink((unsigned long)hcpu, 0);
return NOTIFY_OK;
}
-#endif /* CONFIG_HOTPLUG_CPU */
static int __init flow_cache_init(void)
{