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authorIngo Molnar <mingo@elte.hu>2011-04-27 04:38:30 -0400
committerIngo Molnar <mingo@elte.hu>2011-04-27 04:40:21 -0400
commit32673822e440eb92eb334631eb0a199d0c532d13 (patch)
treec1e55c1793fa17937d9b8e0a9a2946583f1948d5 /arch/s390
parentfa7b69475a6c192853949ba496dd9c37b497b548 (diff)
parent5373db886b791b2bc7811e2c115377916c409a5d (diff)
Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core
Conflicts: include/linux/perf_event.h Merge reason: pick up the latest jump-label enhancements, they are cooked ready. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/s390')
-rw-r--r--arch/s390/Kconfig1
-rw-r--r--arch/s390/include/asm/jump_label.h37
-rw-r--r--arch/s390/kernel/Makefile2
-rw-r--r--arch/s390/kernel/jump_label.c59
4 files changed, 98 insertions, 1 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 2508a6f31588..4a7f14079e03 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -88,6 +88,7 @@ config S390
88 select HAVE_KERNEL_XZ 88 select HAVE_KERNEL_XZ
89 select HAVE_GET_USER_PAGES_FAST 89 select HAVE_GET_USER_PAGES_FAST
90 select HAVE_ARCH_MUTEX_CPU_RELAX 90 select HAVE_ARCH_MUTEX_CPU_RELAX
91 select HAVE_ARCH_JUMP_LABEL if !MARCH_G5
91 select ARCH_INLINE_SPIN_TRYLOCK 92 select ARCH_INLINE_SPIN_TRYLOCK
92 select ARCH_INLINE_SPIN_TRYLOCK_BH 93 select ARCH_INLINE_SPIN_TRYLOCK_BH
93 select ARCH_INLINE_SPIN_LOCK 94 select ARCH_INLINE_SPIN_LOCK
diff --git a/arch/s390/include/asm/jump_label.h b/arch/s390/include/asm/jump_label.h
new file mode 100644
index 000000000000..95a6cf2b5b67
--- /dev/null
+++ b/arch/s390/include/asm/jump_label.h
@@ -0,0 +1,37 @@
1#ifndef _ASM_S390_JUMP_LABEL_H
2#define _ASM_S390_JUMP_LABEL_H
3
4#include <linux/types.h>
5
6#define JUMP_LABEL_NOP_SIZE 6
7
8#ifdef CONFIG_64BIT
9#define ASM_PTR ".quad"
10#define ASM_ALIGN ".balign 8"
11#else
12#define ASM_PTR ".long"
13#define ASM_ALIGN ".balign 4"
14#endif
15
16static __always_inline bool arch_static_branch(struct jump_label_key *key)
17{
18 asm goto("0: brcl 0,0\n"
19 ".pushsection __jump_table, \"aw\"\n"
20 ASM_ALIGN "\n"
21 ASM_PTR " 0b, %l[label], %0\n"
22 ".popsection\n"
23 : : "X" (key) : : label);
24 return false;
25label:
26 return true;
27}
28
29typedef unsigned long jump_label_t;
30
31struct jump_entry {
32 jump_label_t code;
33 jump_label_t target;
34 jump_label_t key;
35};
36
37#endif
diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index 64230bc392fa..5ff15dacb571 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -23,7 +23,7 @@ CFLAGS_sysinfo.o += -Iinclude/math-emu -Iarch/s390/math-emu -w
23obj-y := bitmap.o traps.o time.o process.o base.o early.o setup.o \ 23obj-y := bitmap.o traps.o time.o process.o base.o early.o setup.o \
24 processor.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \ 24 processor.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \
25 s390_ext.o debug.o irq.o ipl.o dis.o diag.o mem_detect.o \ 25 s390_ext.o debug.o irq.o ipl.o dis.o diag.o mem_detect.o \
26 vdso.o vtime.o sysinfo.o nmi.o sclp.o 26 vdso.o vtime.o sysinfo.o nmi.o sclp.o jump_label.o
27 27
28obj-y += $(if $(CONFIG_64BIT),entry64.o,entry.o) 28obj-y += $(if $(CONFIG_64BIT),entry64.o,entry.o)
29obj-y += $(if $(CONFIG_64BIT),reipl64.o,reipl.o) 29obj-y += $(if $(CONFIG_64BIT),reipl64.o,reipl.o)
diff --git a/arch/s390/kernel/jump_label.c b/arch/s390/kernel/jump_label.c
new file mode 100644
index 000000000000..44cc06bedf77
--- /dev/null
+++ b/arch/s390/kernel/jump_label.c
@@ -0,0 +1,59 @@
1/*
2 * Jump label s390 support
3 *
4 * Copyright IBM Corp. 2011
5 * Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
6 */
7#include <linux/module.h>
8#include <linux/uaccess.h>
9#include <linux/stop_machine.h>
10#include <linux/jump_label.h>
11#include <asm/ipl.h>
12
13#ifdef HAVE_JUMP_LABEL
14
15struct insn {
16 u16 opcode;
17 s32 offset;
18} __packed;
19
20struct insn_args {
21 unsigned long *target;
22 struct insn *insn;
23 ssize_t size;
24};
25
26static int __arch_jump_label_transform(void *data)
27{
28 struct insn_args *args = data;
29 int rc;
30
31 rc = probe_kernel_write(args->target, args->insn, args->size);
32 WARN_ON_ONCE(rc < 0);
33 return 0;
34}
35
36void arch_jump_label_transform(struct jump_entry *entry,
37 enum jump_label_type type)
38{
39 struct insn_args args;
40 struct insn insn;
41
42 if (type == JUMP_LABEL_ENABLE) {
43 /* brcl 15,offset */
44 insn.opcode = 0xc0f4;
45 insn.offset = (entry->target - entry->code) >> 1;
46 } else {
47 /* brcl 0,0 */
48 insn.opcode = 0xc004;
49 insn.offset = 0;
50 }
51
52 args.target = (void *) entry->code;
53 args.insn = &insn;
54 args.size = JUMP_LABEL_NOP_SIZE;
55
56 stop_machine(__arch_jump_label_transform, &args, NULL);
57}
58
59#endif