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Subjectasm-i386/mmzone.h macro paren/eval fixes
Okay, this one looks ugly because we're missing some of the definitions
available with which to convert to inline functions (esp. struct page).
A lot of these introduce temporaries and sort of hope names won't clash,
which might be important to whoever cares about -Wshadow.

(1) node_end_pfn() evaluates nid twice
(2) local_mapnr() evaluates kvaddr twice
(3) kern_addr_valid() evaluates kaddr twice
(4) pfn_to_page() evaluates pfn multiple times
(5) page_to_pfn() evaluates page thrice
(6) pfn_valid() doesn't parenthesize its argument


===== include/asm-i386/mmzone.h 1.6 vs edited =====
--- 1.6/include/asm-i386/mmzone.h Wed Sep 25 17:40:59 2002
+++ edited/include/asm-i386/mmzone.h Thu Jan 16 22:37:03 2003
@@ -57,25 +57,47 @@

#define node_mem_map(nid) (NODE_DATA(nid)->node_mem_map)
#define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
-#define node_end_pfn(nid) (NODE_DATA(nid)->node_start_pfn + \
- NODE_DATA(nid)->node_size)
+#define node_end_pfn(nid) \
+({ \
+ pg_data_t *__pgdat = NODE_DATA(nid); \
+ __pgdat->node_start_pfn + __pgdat->node_size; \
+})

-#define local_mapnr(kvaddr) \
- ( (__pa(kvaddr) >> PAGE_SHIFT) - node_start_pfn(kvaddr_to_nid(kvaddr)) )
+#define local_mapnr(kvaddr) \
+({ \
+ unsigned long __pfn = __pa(kvaddr) >> PAGE_SHIFT; \
+ (__pfn - node_start_pfn(pfn_to_nid(__pfn))); \
+})

-#define kern_addr_valid(kaddr) test_bit(local_mapnr(kaddr), \
- NODE_DATA(kvaddr_to_nid(kaddr))->valid_addr_bitmap)
+#define kern_addr_valid(kaddr) \
+({ \
+ unsigned long __kaddr = (unsigned long)(kaddr); \
+ pg_data_t *__pgdat = NODE_DATA(kvaddr_to_nid(__kaddr)); \
+ test_bit(local_mapnr(__kaddr), __pgdat->valid_addr_bitmap); \
+})

-#define pfn_to_page(pfn) (node_mem_map(pfn_to_nid(pfn)) + node_localnr(pfn, pfn_to_nid(pfn)))
-#define page_to_pfn(page) ((page - page_zone(page)->zone_mem_map) + page_zone(page)->zone_start_pfn)
+#define pfn_to_page(pfn) \
+({ \
+ unsigned long __pfn = pfn; \
+ int __node = pfn_to_nid(__pfn); \
+ &node_mem_map(__node)[node_localnr(__pfn,__node)]; \
+})
+
+#define page_to_pfn(pg) \
+({ \
+ struct page *__page = pg; \
+ struct zone *__zone = page_zone(__page); \
+ (unsigned long)(__page - __zone->zone_mem_map) \
+ + __zone->zone_start_pfn; \
+})
#define pmd_page(pmd) (pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT))
/*
* pfn_valid should be made as fast as possible, and the current definition
* is valid for machines that are NUMA, but still contiguous, which is what
* is currently supported. A more generalised, but slower definition would
* be something like this - mbligh:
- * ( pfn_to_pgdat(pfn) && (pfn < node_end_pfn(pfn_to_nid(pfn))) )
+ * ( pfn_to_pgdat(pfn) && ((pfn) < node_end_pfn(pfn_to_nid(pfn))) )
*/
-#define pfn_valid(pfn) (pfn < num_physpages)
+#define pfn_valid(pfn) ((pfn) < num_physpages)
#endif /* CONFIG_DISCONTIGMEM */
#endif /* _ASM_MMZONE_H_ */
-
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