mm/page_alloc.c: introduce kernelcore=mirror option
This patch extends existing "kernelcore" option and introduces
kernelcore=mirror option. By specifying "mirror" instead of specifying
the amount of memory, non-mirrored (non-reliable) region will be
arranged into ZONE_MOVABLE.
[akpm@linux-foundation.org: fix build with CONFIG_HAVE_MEMBLOCK_NODE_MAP=n]
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0d20a19..b8160b9 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -247,6 +247,7 @@
static unsigned long __initdata required_kernelcore;
static unsigned long __initdata required_movablecore;
static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES];
+static bool mirrored_kernelcore;
/* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
int movable_zone;
@@ -4491,6 +4492,9 @@
pg_data_t *pgdat = NODE_DATA(nid);
unsigned long pfn;
unsigned long nr_initialised = 0;
+#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
+ struct memblock_region *r = NULL, *tmp;
+#endif
if (highest_memmap_pfn < end_pfn - 1)
highest_memmap_pfn = end_pfn - 1;
@@ -4516,6 +4520,40 @@
if (!update_defer_init(pgdat, pfn, end_pfn,
&nr_initialised))
break;
+
+#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
+ /*
+ * if not mirrored_kernelcore and ZONE_MOVABLE exists,
+ * range from zone_movable_pfn[nid] to end of each node
+ * should be ZONE_MOVABLE not ZONE_NORMAL. skip it.
+ */
+ if (!mirrored_kernelcore && zone_movable_pfn[nid])
+ if (zone == ZONE_NORMAL &&
+ pfn >= zone_movable_pfn[nid])
+ continue;
+
+ /*
+ * check given memblock attribute by firmware which
+ * can affect kernel memory layout.
+ * if zone==ZONE_MOVABLE but memory is mirrored,
+ * it's an overlapped memmap init. skip it.
+ */
+ if (mirrored_kernelcore && zone == ZONE_MOVABLE) {
+ if (!r ||
+ pfn >= memblock_region_memory_end_pfn(r)) {
+ for_each_memblock(memory, tmp)
+ if (pfn < memblock_region_memory_end_pfn(tmp))
+ break;
+ r = tmp;
+ }
+ if (pfn >= memblock_region_memory_base_pfn(r) &&
+ memblock_is_mirror(r)) {
+ /* already initialized as NORMAL */
+ pfn = memblock_region_memory_end_pfn(r);
+ continue;
+ }
+ }
+#endif
}
/*
@@ -4934,11 +4972,6 @@
*zone_end_pfn = min(node_end_pfn,
arch_zone_highest_possible_pfn[movable_zone]);
- /* Adjust for ZONE_MOVABLE starting within this range */
- } else if (*zone_start_pfn < zone_movable_pfn[nid] &&
- *zone_end_pfn > zone_movable_pfn[nid]) {
- *zone_end_pfn = zone_movable_pfn[nid];
-
/* Check if this whole range is within ZONE_MOVABLE */
} else if (*zone_start_pfn >= zone_movable_pfn[nid])
*zone_start_pfn = *zone_end_pfn;
@@ -5023,6 +5056,7 @@
unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
unsigned long zone_start_pfn, zone_end_pfn;
+ unsigned long nr_absent;
/* When hotadd a new node from cpu_up(), the node should be empty */
if (!node_start_pfn && !node_end_pfn)
@@ -5034,7 +5068,39 @@
adjust_zone_range_for_zone_movable(nid, zone_type,
node_start_pfn, node_end_pfn,
&zone_start_pfn, &zone_end_pfn);
- return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
+ nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
+
+ /*
+ * ZONE_MOVABLE handling.
+ * Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages
+ * and vice versa.
+ */
+ if (zone_movable_pfn[nid]) {
+ if (mirrored_kernelcore) {
+ unsigned long start_pfn, end_pfn;
+ struct memblock_region *r;
+
+ for_each_memblock(memory, r) {
+ start_pfn = clamp(memblock_region_memory_base_pfn(r),
+ zone_start_pfn, zone_end_pfn);
+ end_pfn = clamp(memblock_region_memory_end_pfn(r),
+ zone_start_pfn, zone_end_pfn);
+
+ if (zone_type == ZONE_MOVABLE &&
+ memblock_is_mirror(r))
+ nr_absent += end_pfn - start_pfn;
+
+ if (zone_type == ZONE_NORMAL &&
+ !memblock_is_mirror(r))
+ nr_absent += end_pfn - start_pfn;
+ }
+ } else {
+ if (zone_type == ZONE_NORMAL)
+ nr_absent += node_end_pfn - zone_movable_pfn[nid];
+ }
+ }
+
+ return nr_absent;
}
#else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
@@ -5547,6 +5613,36 @@
}
/*
+ * If kernelcore=mirror is specified, ignore movablecore option
+ */
+ if (mirrored_kernelcore) {
+ bool mem_below_4gb_not_mirrored = false;
+
+ for_each_memblock(memory, r) {
+ if (memblock_is_mirror(r))
+ continue;
+
+ nid = r->nid;
+
+ usable_startpfn = memblock_region_memory_base_pfn(r);
+
+ if (usable_startpfn < 0x100000) {
+ mem_below_4gb_not_mirrored = true;
+ continue;
+ }
+
+ zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
+ min(usable_startpfn, zone_movable_pfn[nid]) :
+ usable_startpfn;
+ }
+
+ if (mem_below_4gb_not_mirrored)
+ pr_warn("This configuration results in unmirrored kernel memory.");
+
+ goto out2;
+ }
+
+ /*
* If movablecore=nn[KMG] was specified, calculate what size of
* kernelcore that corresponds so that memory usable for
* any allocation type is evenly spread. If both kernelcore
@@ -5806,6 +5902,12 @@
*/
static int __init cmdline_parse_kernelcore(char *p)
{
+ /* parse kernelcore=mirror */
+ if (parse_option_str(p, "mirror")) {
+ mirrored_kernelcore = true;
+ return 0;
+ }
+
return cmdline_parse_core(p, &required_kernelcore);
}