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 d21040ed5e5901937327e5806f20218b1d880cb8..80adfbf75065d487a572226eafd21450bc84962d 100644 (file)
--- 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;
                        }