mirror of
https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
synced 2024-10-31 18:09:19 +00:00
memblock: Reimplement memblock_add_region()
memblock_add_region() carefully checked for merge and overlap conditions while adding a new region, which is complicated and makes it difficult to allow arbitrary overlaps or add more merge conditions (e.g. node ID). This re-implements memblock_add_region() such that insertion is done in two steps - all non-overlapping portions of new area are inserted as separate regions first and then memblock_merge_regions() scan and merge all neighbouring compatible regions. This makes addition logic simpler and more versatile and enables adding node information to memblock. Signed-off-by: Tejun Heo <tj@kernel.org> Link: http://lkml.kernel.org/r/1310462166-31469-3-git-send-email-tj@kernel.org Cc: Yinghai Lu <yinghai@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
parent
ed7b56a799
commit
784656f9c6
1 changed files with 115 additions and 90 deletions
205
mm/memblock.c
205
mm/memblock.c
|
@ -251,117 +251,142 @@ static int __init_memblock memblock_double_array(struct memblock_type *type)
|
|||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* memblock_merge_regions - merge neighboring compatible regions
|
||||
* @type: memblock type to scan
|
||||
*
|
||||
* Scan @type and merge neighboring compatible regions.
|
||||
*/
|
||||
static void __init_memblock memblock_merge_regions(struct memblock_type *type)
|
||||
{
|
||||
int i = 0;
|
||||
|
||||
/* cnt never goes below 1 */
|
||||
while (i < type->cnt - 1) {
|
||||
struct memblock_region *this = &type->regions[i];
|
||||
struct memblock_region *next = &type->regions[i + 1];
|
||||
|
||||
if (this->base + this->size != next->base) {
|
||||
BUG_ON(this->base + this->size > next->base);
|
||||
i++;
|
||||
continue;
|
||||
}
|
||||
|
||||
this->size += next->size;
|
||||
memmove(next, next + 1, (type->cnt - (i + 1)) * sizeof(*next));
|
||||
type->cnt--;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* memblock_insert_region - insert new memblock region
|
||||
* @type: memblock type to insert into
|
||||
* @idx: index for the insertion point
|
||||
* @base: base address of the new region
|
||||
* @size: size of the new region
|
||||
*
|
||||
* Insert new memblock region [@base,@base+@size) into @type at @idx.
|
||||
* @type must already have extra room to accomodate the new region.
|
||||
*/
|
||||
static void __init_memblock memblock_insert_region(struct memblock_type *type,
|
||||
int idx, phys_addr_t base,
|
||||
phys_addr_t size)
|
||||
{
|
||||
struct memblock_region *rgn = &type->regions[idx];
|
||||
|
||||
BUG_ON(type->cnt >= type->max);
|
||||
memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
|
||||
rgn->base = base;
|
||||
rgn->size = size;
|
||||
type->cnt++;
|
||||
}
|
||||
|
||||
/**
|
||||
* memblock_add_region - add new memblock region
|
||||
* @type: memblock type to add new region into
|
||||
* @base: base address of the new region
|
||||
* @size: size of the new region
|
||||
*
|
||||
* Add new memblock region [@base,@base+@size) into @type. The new region
|
||||
* is allowed to overlap with existing ones - overlaps don't affect already
|
||||
* existing regions. @type is guaranteed to be minimal (all neighbouring
|
||||
* compatible regions are merged) after the addition.
|
||||
*
|
||||
* RETURNS:
|
||||
* 0 on success, -errno on failure.
|
||||
*/
|
||||
static long __init_memblock memblock_add_region(struct memblock_type *type,
|
||||
phys_addr_t base, phys_addr_t size)
|
||||
{
|
||||
phys_addr_t end = base + size;
|
||||
int i, slot = -1;
|
||||
bool insert = false;
|
||||
phys_addr_t obase = base, end = base + size;
|
||||
int i, nr_new;
|
||||
|
||||
/* First try and coalesce this MEMBLOCK with others */
|
||||
for (i = 0; i < type->cnt; i++) {
|
||||
struct memblock_region *rgn = &type->regions[i];
|
||||
phys_addr_t rend = rgn->base + rgn->size;
|
||||
|
||||
/* Exit if there's no possible hits */
|
||||
if (rgn->base > end || rgn->size == 0)
|
||||
break;
|
||||
|
||||
/* Check if we are fully enclosed within an existing
|
||||
* block
|
||||
*/
|
||||
if (rgn->base <= base && rend >= end)
|
||||
return 0;
|
||||
|
||||
/* Check if we overlap or are adjacent with the bottom
|
||||
* of a block.
|
||||
*/
|
||||
if (base < rgn->base && end >= rgn->base) {
|
||||
/* We extend the bottom of the block down to our
|
||||
* base
|
||||
*/
|
||||
rgn->base = base;
|
||||
rgn->size = rend - base;
|
||||
|
||||
/* Return if we have nothing else to allocate
|
||||
* (fully coalesced)
|
||||
*/
|
||||
if (rend >= end)
|
||||
return 0;
|
||||
|
||||
/* We continue processing from the end of the
|
||||
* coalesced block.
|
||||
*/
|
||||
base = rend;
|
||||
size = end - base;
|
||||
}
|
||||
|
||||
/* Now check if we overlap or are adjacent with the
|
||||
* top of a block
|
||||
*/
|
||||
if (base <= rend && end >= rend) {
|
||||
/* We adjust our base down to enclose the
|
||||
* original block and destroy it. It will be
|
||||
* part of our new allocation. Since we've
|
||||
* freed an entry, we know we won't fail
|
||||
* to allocate one later, so we won't risk
|
||||
* losing the original block allocation.
|
||||
*/
|
||||
size += (base - rgn->base);
|
||||
base = rgn->base;
|
||||
memblock_remove_region(type, i--);
|
||||
}
|
||||
}
|
||||
|
||||
/* If the array is empty, special case, replace the fake
|
||||
* filler region and return
|
||||
*/
|
||||
if ((type->cnt == 1) && (type->regions[0].size == 0)) {
|
||||
/* special case for empty array */
|
||||
if (type->regions[0].size == 0) {
|
||||
WARN_ON(type->cnt != 1);
|
||||
type->regions[0].base = base;
|
||||
type->regions[0].size = size;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* If we are out of space, we fail. It's too late to resize the array
|
||||
* but then this shouldn't have happened in the first place.
|
||||
repeat:
|
||||
/*
|
||||
* The following is executed twice. Once with %false @insert and
|
||||
* then with %true. The first counts the number of regions needed
|
||||
* to accomodate the new area. The second actually inserts them.
|
||||
*/
|
||||
if (WARN_ON(type->cnt >= type->max))
|
||||
return -1;
|
||||
base = obase;
|
||||
nr_new = 0;
|
||||
|
||||
/* Couldn't coalesce the MEMBLOCK, so add it to the sorted table. */
|
||||
for (i = type->cnt - 1; i >= 0; i--) {
|
||||
if (base < type->regions[i].base) {
|
||||
type->regions[i+1].base = type->regions[i].base;
|
||||
type->regions[i+1].size = type->regions[i].size;
|
||||
} else {
|
||||
type->regions[i+1].base = base;
|
||||
type->regions[i+1].size = size;
|
||||
slot = i + 1;
|
||||
for (i = 0; i < type->cnt; i++) {
|
||||
struct memblock_region *rgn = &type->regions[i];
|
||||
phys_addr_t rbase = rgn->base;
|
||||
phys_addr_t rend = rbase + rgn->size;
|
||||
|
||||
if (rbase >= end)
|
||||
break;
|
||||
if (rend <= base)
|
||||
continue;
|
||||
/*
|
||||
* @rgn overlaps. If it separates the lower part of new
|
||||
* area, insert that portion.
|
||||
*/
|
||||
if (rbase > base) {
|
||||
nr_new++;
|
||||
if (insert)
|
||||
memblock_insert_region(type, i++, base,
|
||||
rbase - base);
|
||||
}
|
||||
/* area below @rend is dealt with, forget about it */
|
||||
base = min(rend, end);
|
||||
}
|
||||
if (base < type->regions[0].base) {
|
||||
type->regions[0].base = base;
|
||||
type->regions[0].size = size;
|
||||
slot = 0;
|
||||
}
|
||||
type->cnt++;
|
||||
|
||||
/* The array is full ? Try to resize it. If that fails, we undo
|
||||
* our allocation and return an error
|
||||
/* insert the remaining portion */
|
||||
if (base < end) {
|
||||
nr_new++;
|
||||
if (insert)
|
||||
memblock_insert_region(type, i, base, end - base);
|
||||
}
|
||||
|
||||
/*
|
||||
* If this was the first round, resize array and repeat for actual
|
||||
* insertions; otherwise, merge and return.
|
||||
*/
|
||||
if (type->cnt == type->max && memblock_double_array(type)) {
|
||||
BUG_ON(slot < 0);
|
||||
memblock_remove_region(type, slot);
|
||||
return -1;
|
||||
if (!insert) {
|
||||
while (type->cnt + nr_new > type->max)
|
||||
if (memblock_double_array(type) < 0)
|
||||
return -ENOMEM;
|
||||
insert = true;
|
||||
goto repeat;
|
||||
} else {
|
||||
memblock_merge_regions(type);
|
||||
return 0;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
long __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
|
||||
{
|
||||
return memblock_add_region(&memblock.memory, base, size);
|
||||
|
||||
}
|
||||
|
||||
static long __init_memblock __memblock_remove(struct memblock_type *type,
|
||||
|
|
Loading…
Reference in a new issue