summaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
authorAndrew Morton <akpm@linux-foundation.org>2009-01-09 12:27:08 -0800
committerIngo Molnar <mingo@elte.hu>2009-01-11 03:41:58 +0100
commit53ce3d9564908794ae7dd32969089b57df5fc098 (patch)
treed0eb540d9743155eff6d3c454db3493bf75c9023 /kernel
parentabede81c4fb2e3b85d8760f25e3da39d2c69a134 (diff)
downloadlinux-sh-53ce3d9564908794ae7dd32969089b57df5fc098.tar.gz
smp_call_function_single(): be slightly less stupid
If you do smp_call_function_single(expression-with-side-effects, ...) then expression-with-side-effects never gets evaluated on UP builds. As always, implementing it in C is the correct thing to do. While we're there, uninline it for size and possible header dependency reasons. And create a new kernel/up.c, as a place in which to put uniprocessor-specific code and storage. It should mirror kernel/smp.c. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile6
-rw-r--r--kernel/up.c18
2 files changed, 23 insertions, 1 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index 2921d90ce32f..2aebc4cd7878 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -40,7 +40,11 @@ obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o
obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
-obj-$(CONFIG_USE_GENERIC_SMP_HELPERS) += smp.o
+ifeq ($(CONFIG_USE_GENERIC_SMP_HELPERS),y)
+obj-y += smp.o
+else
+obj-y += up.o
+endif
obj-$(CONFIG_SMP) += spinlock.o
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
diff --git a/kernel/up.c b/kernel/up.c
new file mode 100644
index 000000000000..ce62cc9e9f71
--- /dev/null
+++ b/kernel/up.c
@@ -0,0 +1,18 @@
+/*
+ * Uniprocessor-only support functions. The counterpart to kernel/smp.c
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/smp.h>
+
+int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
+ int wait)
+{
+ WARN_ON(cpuid != 0);
+ local_irq_disable();
+ (func)(info);
+ local_irq_enable();
+ return 0;
+}
+EXPORT_SYMBOL(smp_call_function_single);