[PATCH 11/13] x86: Use absent_pages_in_range() instead of memblock_x86_hole_size()

Tejun Heo
2011-07-12T09:16:54Z

memblock_x86_hole_size() calculates the total size of holes in a given
range according to memblock and is used by numa emulation code and
numa_meminfo_cover_memory().

Since conversion to MEMBLOCK_NODE_MAP, absent_pages_in_range() also
uses memblock and gives the same result. This patch replaces
memblock_x86_hole_size() uses with absent_pages_in_range(). After the
conversion the x86 function doesn't have any user left and is killed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
---
arch/x86/include/asm/memblock.h | 2 -
arch/x86/mm/memblock.c | 52 ---------------------------------------
arch/x86/mm/numa.c | 4 +-
arch/x86/mm/numa_emulation.c | 30 +++++++++++++---------
4 files changed, 20 insertions(+), 68 deletions(-)

diff --git a/arch/x86/include/asm/memblock.h b/arch/x86/include/asm/memblock.h
index a0cc7d6..17a882e 100644
--- a/arch/x86/include/asm/memblock.h
+++ b/arch/x86/include/asm/memblock.h
@@ -6,6 +6,4 @@
void memblock_x86_reserve_range(u64 start, u64 end, char *name);
void memblock_x86_free_range(u64 start, u64 end);

-u64 memblock_x86_hole_size(u64 start, u64 end);
-
#endif
diff --git a/arch/x86/mm/memblock.c b/arch/x86/mm/memblock.c
index a9d0972..7325c5d 100644
--- a/arch/x86/mm/memblock.c
+++ b/arch/x86/mm/memblock.c
@@ -32,55 +32,3 @@ void __init memblock_x86_free_range(u64 start, u64 end)

memblock_free(start, end - start);
}
-
-/*
- * Finds an active region in the address range from start_pfn to last_pfn and
- * returns its range in ei_startpfn and ei_endpfn for the memblock entry.
- */
-static int __init memblock_x86_find_active_region(const struct memblock_region *ei,
- unsigned long start_pfn,
- unsigned long last_pfn,
- unsigned long *ei_startpfn,
- unsigned long *ei_endpfn)
-{
- u64 align = PAGE_SIZE;
-
- *ei_startpfn = round_up(ei->base, align) >> PAGE_SHIFT;
- *ei_endpfn = round_down(ei->base + ei->size, align) >> PAGE_SHIFT;
-
- /* Skip map entries smaller than a page */
- if (*ei_startpfn >= *ei_endpfn)
- return 0;
-
- /* Skip if map is outside the node */
- if (*ei_endpfn <= start_pfn || *ei_startpfn >= last_pfn)
- return 0;
-
- /* Check for overlaps */
- if (*ei_startpfn < start_pfn)
- *ei_startpfn = start_pfn;
- if (*ei_endpfn > last_pfn)
- *ei_endpfn = last_pfn;
-
- return 1;
-}
-
-/*
- * Find the hole size (in bytes) in the memory range.
- * @start: starting address of the memory range to scan
- * @end: ending address of the memory range to scan
- */
-u64 __init memblock_x86_hole_size(u64 start, u64 end)
-{
- unsigned long start_pfn = start >> PAGE_SHIFT;
- unsigned long last_pfn = end >> PAGE_SHIFT;
- unsigned long ei_startpfn, ei_endpfn, ram = 0;
- struct memblock_region *r;
-
- for_each_memblock(memory, r)
- if (memblock_x86_find_active_region(r, start_pfn, last_pfn,
- &ei_startpfn, &ei_endpfn))
- ram += ei_endpfn - ei_startpfn;
-
- return end - start - ((u64)ram << PAGE_SHIFT);
-}
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index f4a40bd..88e5627 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -475,8 +475,8 @@ static bool __init numa_meminfo_cover_memory(const struct numa_meminfo *mi)
numaram = 0;
}

- e820ram = max_pfn - (memblock_x86_hole_size(0,
- PFN_PHYS(max_pfn)) >> PAGE_SHIFT);
+ e820ram = max_pfn - absent_pages_in_range(0, max_pfn);
+
/* We seem to lose 3 pages somewhere. Allow 1M of slack. */
if ((s64)(e820ram - numaram) >= (1 << (20 - PAGE_SHIFT))) {
printk(KERN_ERR "NUMA: nodes only cover %LuMB of your %LuMB e820 RAM. Not used.\n",
diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
index e3d471c..971fe70 100644
--- a/arch/x86/mm/numa_emulation.c
+++ b/arch/x86/mm/numa_emulation.c
@@ -28,6 +28,16 @@ static int __init emu_find_memblk_by_nid(int nid, const struct numa_meminfo *mi)
return -ENOENT;
}

+static u64 mem_hole_size(u64 start, u64 end)
+{
+ unsigned long start_pfn = PFN_UP(start);
+ unsigned long end_pfn = PFN_DOWN(end);
+
+ if (start_pfn < end_pfn)
+ return PFN_PHYS(absent_pages_in_range(start_pfn, end_pfn));
+ return 0;
+}
+
/*
* Sets up nid to range from @start to @end. The return value is -errno if
* something went wrong, 0 otherwise.
@@ -89,7 +99,7 @@ static int __init split_nodes_interleave(struct numa_meminfo *ei,
* Calculate target node size. x86_32 freaks on __udivdi3() so do
* the division in ulong number of pages and convert back.
*/
- size = max_addr - addr - memblock_x86_hole_size(addr, max_addr);
+ size = max_addr - addr - mem_hole_size(addr, max_addr);
size = PFN_PHYS((unsigned long)(size >> PAGE_SHIFT) / nr_nodes);

/*
@@ -135,8 +145,7 @@ static int __init split_nodes_interleave(struct numa_meminfo *ei,
* Continue to add memory to this fake node if its
* non-reserved memory is less than the per-node size.
*/
- while (end - start -
- memblock_x86_hole_size(start, end) < size) {
+ while (end - start - mem_hole_size(start, end) < size) {
end += FAKE_NODE_MIN_SIZE;
if (end > limit) {
end = limit;
@@ -150,7 +159,7 @@ static int __init split_nodes_interleave(struct numa_meminfo *ei,
* this one must extend to the boundary.
*/
if (end < dma32_end && dma32_end - end -
- memblock_x86_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
+ mem_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
end = dma32_end;

/*
@@ -158,8 +167,7 @@ static int __init split_nodes_interleave(struct numa_meminfo *ei,
* next node, this one must extend to the end of the
* physical node.
*/
- if (limit - end -
- memblock_x86_hole_size(end, limit) < size)
+ if (limit - end - mem_hole_size(end, limit) < size)
end = limit;

ret = emu_setup_memblk(ei, pi, nid++ % nr_nodes,
@@ -180,7 +188,7 @@ static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size)
{
u64 end = start + size;

- while (end - start - memblock_x86_hole_size(start, end) < size) {
+ while (end - start - mem_hole_size(start, end) < size) {
end += FAKE_NODE_MIN_SIZE;
if (end > max_addr) {
end = max_addr;
@@ -211,8 +219,7 @@ static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
* creates a uniform distribution of node sizes across the entire
* machine (but not necessarily over physical nodes).
*/
- min_size = (max_addr - addr - memblock_x86_hole_size(addr, max_addr)) /
- MAX_NUMNODES;
+ min_size = (max_addr - addr - mem_hole_size(addr, max_addr)) / MAX_NUMNODES;
min_size = max(min_size, FAKE_NODE_MIN_SIZE);
if ((min_size & FAKE_NODE_MIN_HASH_MASK) < min_size)
min_size = (min_size + FAKE_NODE_MIN_SIZE) &
@@ -252,7 +259,7 @@ static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
* this one must extend to the boundary.
*/
if (end < dma32_end && dma32_end - end -
- memblock_x86_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
+ mem_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
end = dma32_end;

/*
@@ -260,8 +267,7 @@ static int __init split_nodes_size_interleave(struct numa_meminfo *ei,
* next node, this one must extend to the end of the
* physical node.
*/
- if (limit - end -
- memblock_x86_hole_size(end, limit) < size)
+ if (limit - end - mem_hole_size(end, limit) < size)
end = limit;

ret = emu_setup_memblk(ei, pi, nid++ % MAX_NUMNODES,
--
1.7.6