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mm: offset align in alloc_bootmem()

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need offset alignment when node_boot_start's alignment is less than
the alignment required.

use local node_boot_start to match alignment - so don't add extra operation
in search loop.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Yinghai Lu 2008-03-18 12:44:48 -07:00 committed by Ingo Molnar
parent ad09315cad
commit 9a2dc04cf0
1 changed files with 34 additions and 26 deletions
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60
mm/bootmem.c
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@ -206,9 +206,11 @@ void * __init
__alloc_bootmem_core(struct bootmem_data *bdata, unsigned long size,
unsigned long align, unsigned long goal, unsigned long limit)
{
unsigned long offset, remaining_size, areasize, preferred;
unsigned long areasize, preferred;
unsigned long i, start = 0, incr, eidx, end_pfn;
void *ret;
unsigned long node_boot_start;
void *node_bootmem_map;
if (!size) {
printk("__alloc_bootmem_core(): zero-sized request\n");
@ -216,23 +218,29 @@ __alloc_bootmem_core(struct bootmem_data *bdata, unsigned long size,
}
BUG_ON(align & (align-1));
if (limit && bdata->node_boot_start >= limit)
return NULL;
/* on nodes without memory - bootmem_map is NULL */
if (!bdata->node_bootmem_map)
return NULL;
/* bdata->node_boot_start is supposed to be (12+6)bits alignment on x86_64 ? */
node_boot_start = bdata->node_boot_start;
node_bootmem_map = bdata->node_bootmem_map;
if (align) {
node_boot_start = ALIGN(bdata->node_boot_start, align);
if (node_boot_start > bdata->node_boot_start)
node_bootmem_map = (unsigned long *)bdata->node_bootmem_map +
PFN_DOWN(node_boot_start - bdata->node_boot_start)/BITS_PER_LONG;
}
if (limit && node_boot_start >= limit)
return NULL;
end_pfn = bdata->node_low_pfn;
limit = PFN_DOWN(limit);
if (limit && end_pfn > limit)
end_pfn = limit;
eidx = end_pfn - PFN_DOWN(bdata->node_boot_start);
offset = 0;
if (align && (bdata->node_boot_start & (align - 1UL)) != 0)
offset = align - (bdata->node_boot_start & (align - 1UL));
offset = PFN_DOWN(offset);
eidx = end_pfn - PFN_DOWN(node_boot_start);
/*
* We try to allocate bootmem pages above 'goal'
@ -240,15 +248,16 @@ __alloc_bootmem_core(struct bootmem_data *bdata, unsigned long size,
*/
preferred = 0;
if (goal && PFN_DOWN(goal) < end_pfn) {
if (goal > bdata->node_boot_start)
preferred = goal - bdata->node_boot_start;
if (goal > node_boot_start)
preferred = goal - node_boot_start;
if (bdata->last_success >= preferred)
if (bdata->last_success > node_boot_start &&
bdata->last_success - node_boot_start >= preferred)
if (!limit || (limit && limit > bdata->last_success))
preferred = bdata->last_success;
preferred = bdata->last_success - node_boot_start;
}
preferred = PFN_DOWN(ALIGN(preferred, align)) + offset;
preferred = PFN_DOWN(ALIGN(preferred, align));
areasize = (size + PAGE_SIZE-1) / PAGE_SIZE;
incr = align >> PAGE_SHIFT ? : 1;
@ -256,18 +265,18 @@ restart_scan:
for (i = preferred; i < eidx;) {
unsigned long j;
i = find_next_zero_bit(bdata->node_bootmem_map, eidx, i);
i = find_next_zero_bit(node_bootmem_map, eidx, i);
i = ALIGN(i, incr);
if (i >= eidx)
break;
if (test_bit(i, bdata->node_bootmem_map)) {
if (test_bit(i, node_bootmem_map)) {
i += incr;
continue;
}
for (j = i + 1; j < i + areasize; ++j) {
if (j >= eidx)
goto fail_block;
if (test_bit(j, bdata->node_bootmem_map))
if (test_bit(j, node_bootmem_map))
goto fail_block;
}
start = i;
@ -278,14 +287,14 @@ restart_scan:
i += incr;
}
if (preferred > offset) {
preferred = offset;
if (preferred > 0) {
preferred = 0;
goto restart_scan;
}
return NULL;
found:
bdata->last_success = PFN_PHYS(start);
bdata->last_success = PFN_PHYS(start) + node_boot_start;
BUG_ON(start >= eidx);
/*
@ -295,6 +304,7 @@ found:
*/
if (align < PAGE_SIZE &&
bdata->last_offset && bdata->last_pos+1 == start) {
unsigned long offset, remaining_size;
offset = ALIGN(bdata->last_offset, align);
BUG_ON(offset > PAGE_SIZE);
remaining_size = PAGE_SIZE - offset;
@ -303,14 +313,12 @@ found:
/* last_pos unchanged */
bdata->last_offset = offset + size;
ret = phys_to_virt(bdata->last_pos * PAGE_SIZE +
offset +
bdata->node_boot_start);
offset + node_boot_start);
} else {
remaining_size = size - remaining_size;
areasize = (remaining_size + PAGE_SIZE-1) / PAGE_SIZE;
ret = phys_to_virt(bdata->last_pos * PAGE_SIZE +
offset +
bdata->node_boot_start);
offset + node_boot_start);
bdata->last_pos = start + areasize - 1;
bdata->last_offset = remaining_size;
}
@ -318,14 +326,14 @@ found:
} else {
bdata->last_pos = start + areasize - 1;
bdata->last_offset = size & ~PAGE_MASK;
ret = phys_to_virt(start * PAGE_SIZE + bdata->node_boot_start);
ret = phys_to_virt(start * PAGE_SIZE + node_boot_start);
}
/*
* Reserve the area now:
*/
for (i = start; i < start + areasize; i++)
if (unlikely(test_and_set_bit(i, bdata->node_bootmem_map)))
if (unlikely(test_and_set_bit(i, node_bootmem_map)))
BUG();
memset(ret, 0, size);
return ret;