[PATCH] x86-64: Account for module percpu space separately from kernel percpu

Rather than using a single constant PERCPU_ENOUGH_ROOM, compute it as
the sum of kernel_percpu + PERCPU_MODULE_RESERVE.  This is now common
to all architectures; if an architecture wants to set
PERCPU_ENOUGH_ROOM to something special, then it may do so (ia64 is
the only one which does).

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Andi Kleen <ak@suse.de>

1 files changed, 8 insertions, 1 deletions

diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 600e3d387ffc..b72be2f79e6a 100644
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -11,9 +11,16 @@
 
 /* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
 #ifndef PERCPU_ENOUGH_ROOM
-#define PERCPU_ENOUGH_ROOM 32768
+#ifdef CONFIG_MODULES
+#define PERCPU_MODULE_RESERVE   8192
+#else
+#define PERCPU_MODULE_RESERVE   0
 #endif
 
+#define PERCPU_ENOUGH_ROOM                                              \
+        (__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE)
+#endif  /* PERCPU_ENOUGH_ROOM */
+
 /*
  * Must be an lvalue. Since @var must be a simple identifier,
  * we force a syntax error here if it isn't.