x86: apic: Do not use stacked physid_mask_t

We should not use physid_mask_t as a stack based
variable in apic code. This type depends on MAX_APICS
parameter which may be huge enough.

Especially it became a problem with apic NOOP driver which
is portable between 32 bit and 64 bit environment
(where we have really huge MAX_APICS).

So apic driver should operate with pointers and a caller
in turn should aware of allocation physid_mask_t variable.

As a side (but positive) effect -- we may use already
implemented physid_set_mask_of_physid function eliminating
default_apicid_to_cpu_present completely.

Note that physids_coerce and physids_promote turned into static
inline from macro (since macro hides the fact that parameter is
being interpreted as unsigned long, make it explicit).

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
LKML-Reference: <20091109220659.GA5568@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 9 insertions, 7 deletions

diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h
index 79c94500c0bb..61d90b1331c3 100644
--- a/arch/x86/include/asm/mpspec.h
+++ b/arch/x86/include/asm/mpspec.h
@@ -163,14 +163,16 @@ typedef struct physid_mask physid_mask_t;
 #define physids_shift_left(d, s, n)                             \
         bitmap_shift_left((d).mask, (s).mask, n, MAX_APICS)
 
-#define physids_coerce(map)                     ((map).mask[0])
+static inline unsigned long physids_coerce(physid_mask_t *map)
+{
+        return map->mask[0];
+}
 
-#define physids_promote(physids)                                        \
-        ({                                                              \
-                physid_mask_t __physid_mask = PHYSID_MASK_NONE;         \
-                __physid_mask.mask[0] = physids;                        \
-                __physid_mask;                                          \
-        })
+static inline void physids_promote(unsigned long physids, physid_mask_t *map)
+{
+        physids_clear(*map);
+        map->mask[0] = physids;
+}
 
 /* Note: will create very large stack frames if physid_mask_t is big */
 #define physid_mask_of_physid(physid)                                   \