Commit a065de0d 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/tip

Pull x86/asm changes from Ingo Molnar:
 "Assorted single-commit improvements, as usual"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/mtrr: Slightly simplify print_mtrr_state()
  x86/mm/mtrr: Fix alignment determination in range_to_mtrr()
  x86/copy_user_generic: Optimize copy_user_generic with CPU erms feature
  x86/alternatives: Use atomic_xchg() instead atomic_dec_and_test() for stop_machine_text_poke()
parents 3992c032 a7101d15
......@@ -75,22 +75,53 @@ static inline int alternatives_text_reserved(void *start, void *end)
}
#endif /* CONFIG_SMP */
#define OLDINSTR(oldinstr) "661:\n\t" oldinstr "\n662:\n"
#define b_replacement(number) "663"#number
#define e_replacement(number) "664"#number
#define alt_slen "662b-661b"
#define alt_rlen(number) e_replacement(number)"f-"b_replacement(number)"f"
#define ALTINSTR_ENTRY(feature, number) \
" .long 661b - .\n" /* label */ \
" .long " b_replacement(number)"f - .\n" /* new instruction */ \
" .word " __stringify(feature) "\n" /* feature bit */ \
" .byte " alt_slen "\n" /* source len */ \
" .byte " alt_rlen(number) "\n" /* replacement len */
#define DISCARD_ENTRY(number) /* rlen <= slen */ \
" .byte 0xff + (" alt_rlen(number) ") - (" alt_slen ")\n"
#define ALTINSTR_REPLACEMENT(newinstr, feature, number) /* replacement */ \
b_replacement(number)":\n\t" newinstr "\n" e_replacement(number) ":\n\t"
/* alternative assembly primitive: */
#define ALTERNATIVE(oldinstr, newinstr, feature) \
\
"661:\n\t" oldinstr "\n662:\n" \
OLDINSTR(oldinstr) \
".section .altinstructions,\"a\"\n" \
" .long 661b - .\n" /* label */ \
" .long 663f - .\n" /* new instruction */ \
" .word " __stringify(feature) "\n" /* feature bit */ \
" .byte 662b-661b\n" /* sourcelen */ \
" .byte 664f-663f\n" /* replacementlen */ \
ALTINSTR_ENTRY(feature, 1) \
".previous\n" \
".section .discard,\"aw\",@progbits\n" \
" .byte 0xff + (664f-663f) - (662b-661b)\n" /* rlen <= slen */ \
DISCARD_ENTRY(1) \
".previous\n" \
".section .altinstr_replacement, \"ax\"\n" \
"663:\n\t" newinstr "\n664:\n" /* replacement */ \
ALTINSTR_REPLACEMENT(newinstr, feature, 1) \
".previous"
#define ALTERNATIVE_2(oldinstr, newinstr1, feature1, newinstr2, feature2)\
OLDINSTR(oldinstr) \
".section .altinstructions,\"a\"\n" \
ALTINSTR_ENTRY(feature1, 1) \
ALTINSTR_ENTRY(feature2, 2) \
".previous\n" \
".section .discard,\"aw\",@progbits\n" \
DISCARD_ENTRY(1) \
DISCARD_ENTRY(2) \
".previous\n" \
".section .altinstr_replacement, \"ax\"\n" \
ALTINSTR_REPLACEMENT(newinstr1, feature1, 1) \
ALTINSTR_REPLACEMENT(newinstr2, feature2, 2) \
".previous"
/*
......@@ -139,6 +170,19 @@ static inline int alternatives_text_reserved(void *start, void *end)
asm volatile (ALTERNATIVE("call %P[old]", "call %P[new]", feature) \
: output : [old] "i" (oldfunc), [new] "i" (newfunc), ## input)
/*
* Like alternative_call, but there are two features and respective functions.
* If CPU has feature2, function2 is used.
* Otherwise, if CPU has feature1, function1 is used.
* Otherwise, old function is used.
*/
#define alternative_call_2(oldfunc, newfunc1, feature1, newfunc2, feature2, \
output, input...) \
asm volatile (ALTERNATIVE_2("call %P[old]", "call %P[new1]", feature1,\
"call %P[new2]", feature2) \
: output : [old] "i" (oldfunc), [new1] "i" (newfunc1), \
[new2] "i" (newfunc2), ## input)
/*
* use this macro(s) if you need more than one output parameter
* in alternative_io
......
......@@ -17,6 +17,8 @@
/* Handles exceptions in both to and from, but doesn't do access_ok */
__must_check unsigned long
copy_user_enhanced_fast_string(void *to, const void *from, unsigned len);
__must_check unsigned long
copy_user_generic_string(void *to, const void *from, unsigned len);
__must_check unsigned long
copy_user_generic_unrolled(void *to, const void *from, unsigned len);
......@@ -26,9 +28,16 @@ copy_user_generic(void *to, const void *from, unsigned len)
{
unsigned ret;
alternative_call(copy_user_generic_unrolled,
/*
* If CPU has ERMS feature, use copy_user_enhanced_fast_string.
* Otherwise, if CPU has rep_good feature, use copy_user_generic_string.
* Otherwise, use copy_user_generic_unrolled.
*/
alternative_call_2(copy_user_generic_unrolled,
copy_user_generic_string,
X86_FEATURE_REP_GOOD,
copy_user_enhanced_fast_string,
X86_FEATURE_ERMS,
ASM_OUTPUT2("=a" (ret), "=D" (to), "=S" (from),
"=d" (len)),
"1" (to), "2" (from), "3" (len)
......
......@@ -664,7 +664,7 @@ static int __kprobes stop_machine_text_poke(void *data)
struct text_poke_param *p;
int i;
if (atomic_dec_and_test(&stop_machine_first)) {
if (atomic_xchg(&stop_machine_first, 0)) {
for (i = 0; i < tpp->nparams; i++) {
p = &tpp->params[i];
text_poke(p->addr, p->opcode, p->len);
......
......@@ -258,11 +258,11 @@ range_to_mtrr(unsigned int reg, unsigned long range_startk,
/* Compute the maximum size with which we can make a range: */
if (range_startk)
max_align = ffs(range_startk) - 1;
max_align = __ffs(range_startk);
else
max_align = 32;
max_align = BITS_PER_LONG - 1;
align = fls(range_sizek) - 1;
align = __fls(range_sizek);
if (align > max_align)
align = max_align;
......
......@@ -361,11 +361,7 @@ static void __init print_mtrr_state(void)
}
pr_debug("MTRR variable ranges %sabled:\n",
mtrr_state.enabled & 2 ? "en" : "dis");
if (size_or_mask & 0xffffffffUL)
high_width = ffs(size_or_mask & 0xffffffffUL) - 1;
else
high_width = ffs(size_or_mask>>32) + 32 - 1;
high_width = (high_width - (32 - PAGE_SHIFT) + 3) / 4;
high_width = (__ffs64(size_or_mask) - (32 - PAGE_SHIFT) + 3) / 4;
for (i = 0; i < num_var_ranges; ++i) {
if (mtrr_state.var_ranges[i].mask_lo & (1 << 11))
......
......@@ -28,6 +28,7 @@ EXPORT_SYMBOL(__put_user_8);
EXPORT_SYMBOL(copy_user_generic_string);
EXPORT_SYMBOL(copy_user_generic_unrolled);
EXPORT_SYMBOL(copy_user_enhanced_fast_string);
EXPORT_SYMBOL(__copy_user_nocache);
EXPORT_SYMBOL(_copy_from_user);
EXPORT_SYMBOL(_copy_to_user);
......
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