Commit 94bb0c1a authored by David Daney's avatar David Daney Committed by Ralf Baechle

MIPS: jump label: Add MIPS support.

In order not to be left behind, we add jump label support for MIPS.

Tested on 64-bit big endian (Octeon), and 32-bit little endian
(malta/qemu).
Signed-off-by: default avatarDavid Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Baron <jbaron@redhat.com>
Patchwork: https://patchwork.linux-mips.org/patch/1923/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 8d662c8d
......@@ -21,6 +21,7 @@ config MIPS
select HAVE_DMA_API_DEBUG
select HAVE_GENERIC_HARDIRQS
select GENERIC_IRQ_PROBE
select HAVE_ARCH_JUMP_LABEL
menu "Machine selection"
......
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 2010 Cavium Networks, Inc.
*/
#ifndef _ASM_MIPS_JUMP_LABEL_H
#define _ASM_MIPS_JUMP_LABEL_H
#include <linux/types.h>
#ifdef __KERNEL__
#define JUMP_LABEL_NOP_SIZE 4
#ifdef CONFIG_64BIT
#define WORD_INSN ".dword"
#else
#define WORD_INSN ".word"
#endif
#define JUMP_LABEL(key, label) \
do { \
asm goto("1:\tnop\n\t" \
"nop\n\t" \
".pushsection __jump_table, \"a\"\n\t" \
WORD_INSN " 1b, %l[" #label "], %0\n\t" \
".popsection\n\t" \
: : "i" (key) : : label); \
} while (0)
#endif /* __KERNEL__ */
#ifdef CONFIG_64BIT
typedef u64 jump_label_t;
#else
typedef u32 jump_label_t;
#endif
struct jump_entry {
jump_label_t code;
jump_label_t target;
jump_label_t key;
};
#endif /* _ASM_MIPS_JUMP_LABEL_H */
......@@ -107,4 +107,6 @@ obj-$(CONFIG_MIPS_CPUFREQ) += cpufreq/
obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o
CPPFLAGS_vmlinux.lds := $(KBUILD_CFLAGS)
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 2010 Cavium Networks, Inc.
*/
#include <linux/jump_label.h>
#include <linux/kernel.h>
#include <linux/memory.h>
#include <linux/mutex.h>
#include <linux/types.h>
#include <linux/cpu.h>
#include <asm/cacheflush.h>
#include <asm/inst.h>
#ifdef HAVE_JUMP_LABEL
#define J_RANGE_MASK ((1ul << 28) - 1)
void arch_jump_label_transform(struct jump_entry *e,
enum jump_label_type type)
{
union mips_instruction insn;
union mips_instruction *insn_p =
(union mips_instruction *)(unsigned long)e->code;
/* Jump only works within a 256MB aligned region. */
BUG_ON((e->target & ~J_RANGE_MASK) != (e->code & ~J_RANGE_MASK));
/* Target must have 4 byte alignment. */
BUG_ON((e->target & 3) != 0);
if (type == JUMP_LABEL_ENABLE) {
insn.j_format.opcode = j_op;
insn.j_format.target = (e->target & J_RANGE_MASK) >> 2;
} else {
insn.word = 0; /* nop */
}
get_online_cpus();
mutex_lock(&text_mutex);
*insn_p = insn;
flush_icache_range((unsigned long)insn_p,
(unsigned long)insn_p + sizeof(*insn_p));
mutex_unlock(&text_mutex);
put_online_cpus();
}
#endif /* HAVE_JUMP_LABEL */
......@@ -30,6 +30,8 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/jump_label.h>
#include <asm/pgtable.h> /* MODULE_START */
struct mips_hi16 {
......@@ -382,6 +384,9 @@ int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *s;
char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
/* Make jump label nops. */
jump_label_apply_nops(me);
INIT_LIST_HEAD(&me->arch.dbe_list);
for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
if (strcmp("__dbe_table", secstrings + s->sh_name) != 0)
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment