powerpc/mm: Reduce hashtable size when using 64kB pages
At the moment we size the hashtable based on 4kB pages / 2, even on a
64kB kernel. This results in a hashtable that is much larger than it
needs to be.
Grab the real page size and size the hashtable based on that
Note: This only has effect on non hypervisor machines.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 8d5b475..f5bc1b2 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -516,7 +516,7 @@
static unsigned long __init htab_get_table_size(void)
{
- unsigned long mem_size, rnd_mem_size, pteg_count;
+ unsigned long mem_size, rnd_mem_size, pteg_count, psize;
/* If hash size isn't already provided by the platform, we try to
* retrieve it from the device-tree. If it's not there neither, we
@@ -534,7 +534,8 @@
rnd_mem_size <<= 1;
/* # pages / 2 */
- pteg_count = max(rnd_mem_size >> (12 + 1), 1UL << 11);
+ psize = mmu_psize_defs[mmu_virtual_psize].shift;
+ pteg_count = max(rnd_mem_size >> (psize + 1), 1UL << 11);
return pteg_count << 7;
}