---
mm/cpu_alloc.c | 40 +++++++++++++++-------------------------
1 file changed, 15 insertions(+), 25 deletions(-)
Index: linux-2.6/mm/cpu_alloc.c
===================================================================
--- linux-2.6.orig/mm/cpu_alloc.c 2007-11-03 22:18:12.000000000 -0700
+++ linux-2.6/mm/cpu_alloc.c 2007-11-03 23:11:49.000000000 -0700
@@ -235,6 +235,7 @@ out:
u8 cpu_area[NR_CPUS * BLOCK_SIZE];
static DECLARE_BITMAP(cpu_alloc_map, UNITS_PER_BLOCK);
static int units_free = UNITS_PER_BLOCK;
+#define cpu_alloc_map_order CONFIG_CPU_AREA_ORDER
#define units_total UNITS_PER_BLOCK
static inline int expand_cpu_area(gfp_t flags)
@@ -243,8 +244,7 @@ static inline int expand_cpu_area(gfp_t
}
#endif
-static int end_full_alloc; /* 0 .. end_full_alloc are all allocated */
-static int begin_all_free; /* begin_all_free .. units_total are all free */
+static int first_free; /* First known free unit */
/*
* How many units are needed for an object of a given size
@@ -285,49 +285,39 @@ void *cpu_alloc(unsigned long size, gfp_
{
unsigned long start;
int units = size_to_units(size);
- unsigned end;
void *ptr;
int first;
+ unsigned long map_size;
BUG_ON(gfpflags & ~(GFP_RECLAIM_MASK | __GFP_ZERO));
spin_lock(&cpu_alloc_map_lock);
restart:
+ map_size = PAGE_SIZE << cpu_alloc_map_order;
first = 1;
- start = end_full_alloc;
+ start = first_free;
for ( ; ; ) {
- while (start < units_total &&
- test_bit(start, cpu_alloc_map))
- start++;
-
+ start = find_next_zero_bit(cpu_alloc_map, map_size, start);
if (first)
- end_full_alloc = start;
+ first_free = start;
- if (start == units_total) {
+ if (start >= units_total) {
if (!expand_cpu_area(gfpflags))
goto restart;
spin_unlock(&cpu_alloc_map_lock);
return NULL;
}
- /* Ok we found a free cell */
- end = start + 1;
/* Alignment okay ? */
- if (start % (align / UNIT_SIZE) == 0) {
- /* See if we can find enough units for the object */
- while (end < units_total && end - start < units &&
- !test_bit(end, cpu_alloc_map))
- end++;
- if (end - start == units)
+ if (start % (align / UNIT_SIZE) == 0 &&
+ find_next_bit(cpu_alloc_map, map_size, start + 1)
+ >= start + units);
break;
- }
- start = end;
+ start++;
first = 0;
};
if (first)
- end_full_alloc = end;
- if (end > begin_all_free)
- begin_all_free = end;
+ first_free = start + units;
set_map(start, units);
units_free -= units;
@@ -364,8 +354,8 @@ void cpu_free(void *start, unsigned long
clear_map(index, units);
units_free += units;
__count_vm_events(CPU_BYTES, -units * UNIT_SIZE);
- if (index < end_full_alloc)
- end_full_alloc = index;
+ if (index < first_free)
+ first_free = index;
spin_unlock(&cpu_alloc_map_lock);
}
EXPORT_SYMBOL(cpu_free);