[PATCH 1/8] percpu: clean up percpu constants

Tejun Heo
2009-03-06T06:48:16Z

Impact: cleaup

Make the following cleanups.

* There isn't much arch-specific about PERCPU_MODULE_RESERVE. Always
define it whether arch overrides PERCPU_ENOUGH_ROOM or not.

* blackfin overrides PERCPU_ENOUGH_ROOM to align static area size. Do
it by default.

* percpu allocation sizes doesn't have much to do with the page size.
Don't use PAGE_SHIFT in their definition.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Bryan Wu <cooloney@kernel.org>
---
arch/blackfin/include/asm/percpu.h | 10 ----------
include/linux/percpu.h | 24 +++++++++++++-----------
2 files changed, 13 insertions(+), 21 deletions(-)

diff --git a/arch/blackfin/include/asm/percpu.h b/arch/blackfin/include/asm/percpu.h
index 797c0c1..c94c7bc 100644
--- a/arch/blackfin/include/asm/percpu.h
+++ b/arch/blackfin/include/asm/percpu.h
@@ -3,14 +3,4 @@

#include <asm-generic/percpu.h>

-#ifdef CONFIG_MODULES
-#define PERCPU_MODULE_RESERVE 8192
-#else
-#define PERCPU_MODULE_RESERVE 0
-#endif
-
-#define PERCPU_ENOUGH_ROOM \
- (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
- PERCPU_MODULE_RESERVE)
-
#endif /* __ARCH_BLACKFIN_PERCPU__ */
diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 545b068..2d34b03 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -5,6 +5,7 @@
#include <linux/slab.h> /* For kmalloc() */
#include <linux/smp.h>
#include <linux/cpumask.h>
+#include <linux/pfn.h>

#include <asm/percpu.h>

@@ -52,17 +53,18 @@
#define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
#define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)

-/* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
-#ifndef PERCPU_ENOUGH_ROOM
+/* enough to cover all DEFINE_PER_CPUs in modules */
#ifdef CONFIG_MODULES
-#define PERCPU_MODULE_RESERVE 8192
+#define PERCPU_MODULE_RESERVE (8 << 10)
#else
-#define PERCPU_MODULE_RESERVE 0
+#define PERCPU_MODULE_RESERVE 0
#endif

+#ifndef PERCPU_ENOUGH_ROOM
#define PERCPU_ENOUGH_ROOM \
- (__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE)
-#endif /* PERCPU_ENOUGH_ROOM */
+ (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \
+ PERCPU_MODULE_RESERVE)
+#endif

/*
* Must be an lvalue. Since @var must be a simple identifier,
@@ -79,7 +81,7 @@
#ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA

/* minimum unit size, also is the maximum supported allocation size */
-#define PCPU_MIN_UNIT_SIZE (16UL << PAGE_SHIFT)
+#define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10)

/*
* PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy
@@ -96,15 +98,15 @@
#ifndef PERCPU_DYNAMIC_RESERVE
# if BITS_PER_LONG > 32
# ifdef CONFIG_MODULES
-# define PERCPU_DYNAMIC_RESERVE (6 << PAGE_SHIFT)
+# define PERCPU_DYNAMIC_RESERVE (24 << 10)
# else
-# define PERCPU_DYNAMIC_RESERVE (4 << PAGE_SHIFT)
+# define PERCPU_DYNAMIC_RESERVE (16 << 10)
# endif
# else
# ifdef CONFIG_MODULES
-# define PERCPU_DYNAMIC_RESERVE (4 << PAGE_SHIFT)
+# define PERCPU_DYNAMIC_RESERVE (16 << 10)
# else
-# define PERCPU_DYNAMIC_RESERVE (2 << PAGE_SHIFT)
+# define PERCPU_DYNAMIC_RESERVE (8 << 10)
# endif
# endif
#endif /* PERCPU_DYNAMIC_RESERVE */
--
1.6.0.2