s390/mm: speedup storage key initialization
Use sske with multiple block control to initialize storage keys within
a 1 MB frame at once.
It turned out that the sske with mb=1 is an order of magnitude faster
than pfmf. This is only an issue for very large systems (several 100GB)
where storage key initialization could last more than a minute.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c
index d21040e..80adfbf 100644
--- a/arch/s390/mm/pageattr.c
+++ b/arch/s390/mm/pageattr.c
@@ -9,31 +9,25 @@
#include <asm/pgtable.h>
#include <asm/page.h>
+static inline unsigned long sske_frame(unsigned long addr, unsigned char skey)
+{
+ asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],9,0"
+ : [addr] "+a" (addr) : [skey] "d" (skey));
+ return addr;
+}
+
void storage_key_init_range(unsigned long start, unsigned long end)
{
- unsigned long boundary, function, size;
+ unsigned long boundary, size;
while (start < end) {
- if (MACHINE_HAS_EDAT2) {
- /* set storage keys for a 2GB frame */
- function = 0x22000 | PAGE_DEFAULT_KEY;
- size = 1UL << 31;
- boundary = (start + size) & ~(size - 1);
- if (boundary <= end) {
- do {
- start = pfmf(function, start);
- } while (start < boundary);
- continue;
- }
- }
if (MACHINE_HAS_EDAT1) {
/* set storage keys for a 1MB frame */
- function = 0x21000 | PAGE_DEFAULT_KEY;
size = 1UL << 20;
boundary = (start + size) & ~(size - 1);
if (boundary <= end) {
do {
- start = pfmf(function, start);
+ start = sske_frame(start, PAGE_DEFAULT_KEY);
} while (start < boundary);
continue;
}