Commit 7421a10d authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: Use .cfi_sections for assembly code
  x86-64: Reduce SMP locks table size
  x86, asm: Introduce and use percpu_inc()
parents 752f114f 9e565292
......@@ -95,8 +95,9 @@ sp-$(CONFIG_X86_64) := rsp
cfi := $(call as-instr,.cfi_startproc\n.cfi_rel_offset $(sp-y)$(comma)0\n.cfi_endproc,-DCONFIG_AS_CFI=1)
# is .cfi_signal_frame supported too?
cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1)
KBUILD_AFLAGS += $(cfi) $(cfi-sigframe)
KBUILD_CFLAGS += $(cfi) $(cfi-sigframe)
cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1)
KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections)
KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections)
LDFLAGS := -m elf_$(UTS_MACHINE)
......
......@@ -6,8 +6,8 @@
.macro LOCK_PREFIX
1: lock
.section .smp_locks,"a"
_ASM_ALIGN
_ASM_PTR 1b
.balign 4
.long 1b - .
.previous
.endm
#else
......
......@@ -30,8 +30,8 @@
#ifdef CONFIG_SMP
#define LOCK_PREFIX \
".section .smp_locks,\"a\"\n" \
_ASM_ALIGN "\n" \
_ASM_PTR "661f\n" /* address */ \
".balign 4\n" \
".long 661f - .\n" /* offset */ \
".previous\n" \
"661:\n\tlock; "
......
......@@ -34,6 +34,18 @@
#define CFI_SIGNAL_FRAME
#endif
#if defined(CONFIG_AS_CFI_SECTIONS) && defined(__ASSEMBLY__)
/*
* Emit CFI data in .debug_frame sections, not .eh_frame sections.
* The latter we currently just discard since we don't do DWARF
* unwinding at runtime. So only the offline DWARF information is
* useful to anyone. Note we should not use this directive if this
* file is used in the vDSO assembly, or if vmlinux.lds.S gets
* changed so it doesn't discard .eh_frame.
*/
.cfi_sections .debug_frame
#endif
#else
/*
......
......@@ -35,7 +35,7 @@ DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
#define __ARCH_IRQ_STAT
#define inc_irq_stat(member) percpu_add(irq_stat.member, 1)
#define inc_irq_stat(member) percpu_inc(irq_stat.member)
#define local_softirq_pending() percpu_read(irq_stat.__softirq_pending)
......
......@@ -190,6 +190,29 @@ do { \
pfo_ret__; \
})
#define percpu_unary_op(op, var) \
({ \
switch (sizeof(var)) { \
case 1: \
asm(op "b "__percpu_arg(0) \
: "+m" (var)); \
break; \
case 2: \
asm(op "w "__percpu_arg(0) \
: "+m" (var)); \
break; \
case 4: \
asm(op "l "__percpu_arg(0) \
: "+m" (var)); \
break; \
case 8: \
asm(op "q "__percpu_arg(0) \
: "+m" (var)); \
break; \
default: __bad_percpu_size(); \
} \
})
/*
* percpu_read() makes gcc load the percpu variable every time it is
* accessed while percpu_read_stable() allows the value to be cached.
......@@ -207,6 +230,7 @@ do { \
#define percpu_and(var, val) percpu_to_op("and", var, val)
#define percpu_or(var, val) percpu_to_op("or", var, val)
#define percpu_xor(var, val) percpu_to_op("xor", var, val)
#define percpu_inc(var) percpu_unary_op("inc", var)
#define __this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
#define __this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
......
......@@ -194,7 +194,7 @@ static void __init_or_module add_nops(void *insns, unsigned int len)
}
extern struct alt_instr __alt_instructions[], __alt_instructions_end[];
extern u8 *__smp_locks[], *__smp_locks_end[];
extern s32 __smp_locks[], __smp_locks_end[];
static void *text_poke_early(void *addr, const void *opcode, size_t len);
/* Replace instructions with better alternatives for this CPU type.
......@@ -235,37 +235,39 @@ void __init_or_module apply_alternatives(struct alt_instr *start,
#ifdef CONFIG_SMP
static void alternatives_smp_lock(u8 **start, u8 **end, u8 *text, u8 *text_end)
static void alternatives_smp_lock(const s32 *start, const s32 *end,
u8 *text, u8 *text_end)
{
u8 **ptr;
const s32 *poff;
mutex_lock(&text_mutex);
for (ptr = start; ptr < end; ptr++) {
if (*ptr < text)
continue;
if (*ptr > text_end)
for (poff = start; poff < end; poff++) {
u8 *ptr = (u8 *)poff + *poff;
if (!*poff || ptr < text || ptr >= text_end)
continue;
/* turn DS segment override prefix into lock prefix */
text_poke(*ptr, ((unsigned char []){0xf0}), 1);
text_poke(ptr, ((unsigned char []){0xf0}), 1);
};
mutex_unlock(&text_mutex);
}
static void alternatives_smp_unlock(u8 **start, u8 **end, u8 *text, u8 *text_end)
static void alternatives_smp_unlock(const s32 *start, const s32 *end,
u8 *text, u8 *text_end)
{
u8 **ptr;
const s32 *poff;
if (noreplace_smp)
return;
mutex_lock(&text_mutex);
for (ptr = start; ptr < end; ptr++) {
if (*ptr < text)
continue;
if (*ptr > text_end)
for (poff = start; poff < end; poff++) {
u8 *ptr = (u8 *)poff + *poff;
if (!*poff || ptr < text || ptr >= text_end)
continue;
/* turn lock prefix into DS segment override prefix */
text_poke(*ptr, ((unsigned char []){0x3E}), 1);
text_poke(ptr, ((unsigned char []){0x3E}), 1);
};
mutex_unlock(&text_mutex);
}
......@@ -276,8 +278,8 @@ struct smp_alt_module {
char *name;
/* ptrs to lock prefixes */
u8 **locks;
u8 **locks_end;
const s32 *locks;
const s32 *locks_end;
/* .text segment, needed to avoid patching init code ;) */
u8 *text;
......@@ -398,16 +400,19 @@ void alternatives_smp_switch(int smp)
int alternatives_text_reserved(void *start, void *end)
{
struct smp_alt_module *mod;
u8 **ptr;
const s32 *poff;
u8 *text_start = start;
u8 *text_end = end;
list_for_each_entry(mod, &smp_alt_modules, next) {
if (mod->text > text_end || mod->text_end < text_start)
continue;
for (ptr = mod->locks; ptr < mod->locks_end; ptr++)
if (text_start <= *ptr && text_end >= *ptr)
for (poff = mod->locks; poff < mod->locks_end; poff++) {
const u8 *ptr = (const u8 *)poff + *poff;
if (text_start <= ptr && text_end > ptr)
return 1;
}
}
return 0;
......
......@@ -539,7 +539,7 @@ void machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
struct mce m;
int i;
__get_cpu_var(mce_poll_count)++;
percpu_inc(mce_poll_count);
mce_setup(&m);
......@@ -934,7 +934,7 @@ void do_machine_check(struct pt_regs *regs, long error_code)
atomic_inc(&mce_entry);
__get_cpu_var(mce_exception_count)++;
percpu_inc(mce_exception_count);
if (notify_die(DIE_NMI, "machine check", regs, error_code,
18, SIGKILL) == NOTIFY_STOP)
......
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