aboutsummaryrefslogtreecommitdiffstats
path: root/arch/alpha
diff options
context:
space:
mode:
authorIvan Kokshaysky <ink@jurassic.park.msu.ru>2009-03-31 18:23:35 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-04-01 11:59:16 -0400
commita6209d6d71f2ab8c63cc1587ef65490d83022baf (patch)
tree2490d7adf757c9ea00c30fb8f75171d6b8772d3a /arch/alpha
parenta94066992b3050a7bd9a82bf73bf19f6052d2f82 (diff)
alpha: xchg/cmpxchg cleanup and fixes
- "_local" versions of xchg/cmpxchg functions duplicate code of non-local ones (quite a few pages of assembler), except memory barriers. We can generate these two variants from a single header file using simple macros; - convert xchg macro back to inline function using always_inline attribute; - use proper argument types for cmpxchg_u8/u16 functions to fix a problem with negative arguments. Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/alpha')
-rw-r--r--arch/alpha/include/asm/system.h547
-rw-r--r--arch/alpha/include/asm/xchg.h258
2 files changed, 308 insertions, 497 deletions
diff --git a/arch/alpha/include/asm/system.h b/arch/alpha/include/asm/system.h
index afe20fa58c99..5aa40cca4f23 100644
--- a/arch/alpha/include/asm/system.h
+++ b/arch/alpha/include/asm/system.h
@@ -309,518 +309,71 @@ extern int __min_ipl;
309#define tbia() __tbi(-2, /* no second argument */) 309#define tbia() __tbi(-2, /* no second argument */)
310 310
311/* 311/*
312 * Atomic exchange. 312 * Atomic exchange routines.
313 * Since it can be used to implement critical sections
314 * it must clobber "memory" (also for interrupts in UP).
315 */ 313 */
316 314
317static inline unsigned long 315#define __ASM__MB
318__xchg_u8(volatile char *m, unsigned long val) 316#define ____xchg(type, args...) __xchg ## type ## _local(args)
319{ 317#define ____cmpxchg(type, args...) __cmpxchg ## type ## _local(args)
320 unsigned long ret, tmp, addr64; 318#include <asm/xchg.h>
321
322 __asm__ __volatile__(
323 " andnot %4,7,%3\n"
324 " insbl %1,%4,%1\n"
325 "1: ldq_l %2,0(%3)\n"
326 " extbl %2,%4,%0\n"
327 " mskbl %2,%4,%2\n"
328 " or %1,%2,%2\n"
329 " stq_c %2,0(%3)\n"
330 " beq %2,2f\n"
331#ifdef CONFIG_SMP
332 " mb\n"
333#endif
334 ".subsection 2\n"
335 "2: br 1b\n"
336 ".previous"
337 : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
338 : "r" ((long)m), "1" (val) : "memory");
339
340 return ret;
341}
342
343static inline unsigned long
344__xchg_u16(volatile short *m, unsigned long val)
345{
346 unsigned long ret, tmp, addr64;
347
348 __asm__ __volatile__(
349 " andnot %4,7,%3\n"
350 " inswl %1,%4,%1\n"
351 "1: ldq_l %2,0(%3)\n"
352 " extwl %2,%4,%0\n"
353 " mskwl %2,%4,%2\n"
354 " or %1,%2,%2\n"
355 " stq_c %2,0(%3)\n"
356 " beq %2,2f\n"
357#ifdef CONFIG_SMP
358 " mb\n"
359#endif
360 ".subsection 2\n"
361 "2: br 1b\n"
362 ".previous"
363 : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
364 : "r" ((long)m), "1" (val) : "memory");
365
366 return ret;
367}
368
369static inline unsigned long
370__xchg_u32(volatile int *m, unsigned long val)
371{
372 unsigned long dummy;
373
374 __asm__ __volatile__(
375 "1: ldl_l %0,%4\n"
376 " bis $31,%3,%1\n"
377 " stl_c %1,%2\n"
378 " beq %1,2f\n"
379#ifdef CONFIG_SMP
380 " mb\n"
381#endif
382 ".subsection 2\n"
383 "2: br 1b\n"
384 ".previous"
385 : "=&r" (val), "=&r" (dummy), "=m" (*m)
386 : "rI" (val), "m" (*m) : "memory");
387
388 return val;
389}
390
391static inline unsigned long
392__xchg_u64(volatile long *m, unsigned long val)
393{
394 unsigned long dummy;
395
396 __asm__ __volatile__(
397 "1: ldq_l %0,%4\n"
398 " bis $31,%3,%1\n"
399 " stq_c %1,%2\n"
400 " beq %1,2f\n"
401#ifdef CONFIG_SMP
402 " mb\n"
403#endif
404 ".subsection 2\n"
405 "2: br 1b\n"
406 ".previous"
407 : "=&r" (val), "=&r" (dummy), "=m" (*m)
408 : "rI" (val), "m" (*m) : "memory");
409 319
410 return val; 320#define xchg_local(ptr,x) \
411} 321 ({ \
412 322 __typeof__(*(ptr)) _x_ = (x); \
413/* This function doesn't exist, so you'll get a linker error 323 (__typeof__(*(ptr))) __xchg_local((ptr), (unsigned long)_x_, \
414 if something tries to do an invalid xchg(). */ 324 sizeof(*(ptr))); \
415extern void __xchg_called_with_bad_pointer(void);
416
417#define __xchg(ptr, x, size) \
418({ \
419 unsigned long __xchg__res; \
420 volatile void *__xchg__ptr = (ptr); \
421 switch (size) { \
422 case 1: __xchg__res = __xchg_u8(__xchg__ptr, x); break; \
423 case 2: __xchg__res = __xchg_u16(__xchg__ptr, x); break; \
424 case 4: __xchg__res = __xchg_u32(__xchg__ptr, x); break; \
425 case 8: __xchg__res = __xchg_u64(__xchg__ptr, x); break; \
426 default: __xchg_called_with_bad_pointer(); __xchg__res = x; \
427 } \
428 __xchg__res; \
429})
430
431#define xchg(ptr,x) \
432 ({ \
433 __typeof__(*(ptr)) _x_ = (x); \
434 (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
435 }) 325 })
436 326
437static inline unsigned long 327#define cmpxchg_local(ptr, o, n) \
438__xchg_u8_local(volatile char *m, unsigned long val) 328 ({ \
439{ 329 __typeof__(*(ptr)) _o_ = (o); \
440 unsigned long ret, tmp, addr64; 330 __typeof__(*(ptr)) _n_ = (n); \
441 331 (__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_, \
442 __asm__ __volatile__( 332 (unsigned long)_n_, \
443 " andnot %4,7,%3\n" 333 sizeof(*(ptr))); \
444 " insbl %1,%4,%1\n"
445 "1: ldq_l %2,0(%3)\n"
446 " extbl %2,%4,%0\n"
447 " mskbl %2,%4,%2\n"
448 " or %1,%2,%2\n"
449 " stq_c %2,0(%3)\n"
450 " beq %2,2f\n"
451 ".subsection 2\n"
452 "2: br 1b\n"
453 ".previous"
454 : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
455 : "r" ((long)m), "1" (val) : "memory");
456
457 return ret;
458}
459
460static inline unsigned long
461__xchg_u16_local(volatile short *m, unsigned long val)
462{
463 unsigned long ret, tmp, addr64;
464
465 __asm__ __volatile__(
466 " andnot %4,7,%3\n"
467 " inswl %1,%4,%1\n"
468 "1: ldq_l %2,0(%3)\n"
469 " extwl %2,%4,%0\n"
470 " mskwl %2,%4,%2\n"
471 " or %1,%2,%2\n"
472 " stq_c %2,0(%3)\n"
473 " beq %2,2f\n"
474 ".subsection 2\n"
475 "2: br 1b\n"
476 ".previous"
477 : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
478 : "r" ((long)m), "1" (val) : "memory");
479
480 return ret;
481}
482
483static inline unsigned long
484__xchg_u32_local(volatile int *m, unsigned long val)
485{
486 unsigned long dummy;
487
488 __asm__ __volatile__(
489 "1: ldl_l %0,%4\n"
490 " bis $31,%3,%1\n"
491 " stl_c %1,%2\n"
492 " beq %1,2f\n"
493 ".subsection 2\n"
494 "2: br 1b\n"
495 ".previous"
496 : "=&r" (val), "=&r" (dummy), "=m" (*m)
497 : "rI" (val), "m" (*m) : "memory");
498
499 return val;
500}
501
502static inline unsigned long
503__xchg_u64_local(volatile long *m, unsigned long val)
504{
505 unsigned long dummy;
506
507 __asm__ __volatile__(
508 "1: ldq_l %0,%4\n"
509 " bis $31,%3,%1\n"
510 " stq_c %1,%2\n"
511 " beq %1,2f\n"
512 ".subsection 2\n"
513 "2: br 1b\n"
514 ".previous"
515 : "=&r" (val), "=&r" (dummy), "=m" (*m)
516 : "rI" (val), "m" (*m) : "memory");
517
518 return val;
519}
520
521#define __xchg_local(ptr, x, size) \
522({ \
523 unsigned long __xchg__res; \
524 volatile void *__xchg__ptr = (ptr); \
525 switch (size) { \
526 case 1: __xchg__res = __xchg_u8_local(__xchg__ptr, x); break; \
527 case 2: __xchg__res = __xchg_u16_local(__xchg__ptr, x); break; \
528 case 4: __xchg__res = __xchg_u32_local(__xchg__ptr, x); break; \
529 case 8: __xchg__res = __xchg_u64_local(__xchg__ptr, x); break; \
530 default: __xchg_called_with_bad_pointer(); __xchg__res = x; \
531 } \
532 __xchg__res; \
533})
534
535#define xchg_local(ptr,x) \
536 ({ \
537 __typeof__(*(ptr)) _x_ = (x); \
538 (__typeof__(*(ptr))) __xchg_local((ptr), (unsigned long)_x_, \
539 sizeof(*(ptr))); \
540 }) 334 })
541 335
542/* 336#define cmpxchg64_local(ptr, o, n) \
543 * Atomic compare and exchange. Compare OLD with MEM, if identical, 337 ({ \
544 * store NEW in MEM. Return the initial value in MEM. Success is 338 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
545 * indicated by comparing RETURN with OLD. 339 cmpxchg_local((ptr), (o), (n)); \
546 * 340 })
547 * The memory barrier should be placed in SMP only when we actually
548 * make the change. If we don't change anything (so if the returned
549 * prev is equal to old) then we aren't acquiring anything new and
550 * we don't need any memory barrier as far I can tell.
551 */
552
553#define __HAVE_ARCH_CMPXCHG 1
554
555static inline unsigned long
556__cmpxchg_u8(volatile char *m, long old, long new)
557{
558 unsigned long prev, tmp, cmp, addr64;
559
560 __asm__ __volatile__(
561 " andnot %5,7,%4\n"
562 " insbl %1,%5,%1\n"
563 "1: ldq_l %2,0(%4)\n"
564 " extbl %2,%5,%0\n"
565 " cmpeq %0,%6,%3\n"
566 " beq %3,2f\n"
567 " mskbl %2,%5,%2\n"
568 " or %1,%2,%2\n"
569 " stq_c %2,0(%4)\n"
570 " beq %2,3f\n"
571#ifdef CONFIG_SMP
572 " mb\n"
573#endif
574 "2:\n"
575 ".subsection 2\n"
576 "3: br 1b\n"
577 ".previous"
578 : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
579 : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
580
581 return prev;
582}
583
584static inline unsigned long
585__cmpxchg_u16(volatile short *m, long old, long new)
586{
587 unsigned long prev, tmp, cmp, addr64;
588
589 __asm__ __volatile__(
590 " andnot %5,7,%4\n"
591 " inswl %1,%5,%1\n"
592 "1: ldq_l %2,0(%4)\n"
593 " extwl %2,%5,%0\n"
594 " cmpeq %0,%6,%3\n"
595 " beq %3,2f\n"
596 " mskwl %2,%5,%2\n"
597 " or %1,%2,%2\n"
598 " stq_c %2,0(%4)\n"
599 " beq %2,3f\n"
600#ifdef CONFIG_SMP
601 " mb\n"
602#endif
603 "2:\n"
604 ".subsection 2\n"
605 "3: br 1b\n"
606 ".previous"
607 : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
608 : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
609
610 return prev;
611}
612
613static inline unsigned long
614__cmpxchg_u32(volatile int *m, int old, int new)
615{
616 unsigned long prev, cmp;
617
618 __asm__ __volatile__(
619 "1: ldl_l %0,%5\n"
620 " cmpeq %0,%3,%1\n"
621 " beq %1,2f\n"
622 " mov %4,%1\n"
623 " stl_c %1,%2\n"
624 " beq %1,3f\n"
625#ifdef CONFIG_SMP
626 " mb\n"
627#endif
628 "2:\n"
629 ".subsection 2\n"
630 "3: br 1b\n"
631 ".previous"
632 : "=&r"(prev), "=&r"(cmp), "=m"(*m)
633 : "r"((long) old), "r"(new), "m"(*m) : "memory");
634
635 return prev;
636}
637 341
638static inline unsigned long
639__cmpxchg_u64(volatile long *m, unsigned long old, unsigned long new)
640{
641 unsigned long prev, cmp;
642
643 __asm__ __volatile__(
644 "1: ldq_l %0,%5\n"
645 " cmpeq %0,%3,%1\n"
646 " beq %1,2f\n"
647 " mov %4,%1\n"
648 " stq_c %1,%2\n"
649 " beq %1,3f\n"
650#ifdef CONFIG_SMP 342#ifdef CONFIG_SMP
651 " mb\n" 343#undef __ASM__MB
344#define __ASM__MB "\tmb\n"
652#endif 345#endif
653 "2:\n" 346#undef ____xchg
654 ".subsection 2\n" 347#undef ____cmpxchg
655 "3: br 1b\n" 348#define ____xchg(type, args...) __xchg ##type(args)
656 ".previous" 349#define ____cmpxchg(type, args...) __cmpxchg ##type(args)
657 : "=&r"(prev), "=&r"(cmp), "=m"(*m) 350#include <asm/xchg.h>
658 : "r"((long) old), "r"(new), "m"(*m) : "memory"); 351
659 352#define xchg(ptr,x) \
660 return prev; 353 ({ \
661} 354 __typeof__(*(ptr)) _x_ = (x); \
662 355 (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, \
663/* This function doesn't exist, so you'll get a linker error 356 sizeof(*(ptr))); \
664 if something tries to do an invalid cmpxchg(). */
665extern void __cmpxchg_called_with_bad_pointer(void);
666
667static __always_inline unsigned long
668__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
669{
670 switch (size) {
671 case 1:
672 return __cmpxchg_u8(ptr, old, new);
673 case 2:
674 return __cmpxchg_u16(ptr, old, new);
675 case 4:
676 return __cmpxchg_u32(ptr, old, new);
677 case 8:
678 return __cmpxchg_u64(ptr, old, new);
679 }
680 __cmpxchg_called_with_bad_pointer();
681 return old;
682}
683
684#define cmpxchg(ptr, o, n) \
685 ({ \
686 __typeof__(*(ptr)) _o_ = (o); \
687 __typeof__(*(ptr)) _n_ = (n); \
688 (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
689 (unsigned long)_n_, sizeof(*(ptr))); \
690 }) 357 })
691#define cmpxchg64(ptr, o, n) \
692 ({ \
693 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
694 cmpxchg((ptr), (o), (n)); \
695 })
696
697static inline unsigned long
698__cmpxchg_u8_local(volatile char *m, long old, long new)
699{
700 unsigned long prev, tmp, cmp, addr64;
701
702 __asm__ __volatile__(
703 " andnot %5,7,%4\n"
704 " insbl %1,%5,%1\n"
705 "1: ldq_l %2,0(%4)\n"
706 " extbl %2,%5,%0\n"
707 " cmpeq %0,%6,%3\n"
708 " beq %3,2f\n"
709 " mskbl %2,%5,%2\n"
710 " or %1,%2,%2\n"
711 " stq_c %2,0(%4)\n"
712 " beq %2,3f\n"
713 "2:\n"
714 ".subsection 2\n"
715 "3: br 1b\n"
716 ".previous"
717 : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
718 : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
719
720 return prev;
721}
722
723static inline unsigned long
724__cmpxchg_u16_local(volatile short *m, long old, long new)
725{
726 unsigned long prev, tmp, cmp, addr64;
727
728 __asm__ __volatile__(
729 " andnot %5,7,%4\n"
730 " inswl %1,%5,%1\n"
731 "1: ldq_l %2,0(%4)\n"
732 " extwl %2,%5,%0\n"
733 " cmpeq %0,%6,%3\n"
734 " beq %3,2f\n"
735 " mskwl %2,%5,%2\n"
736 " or %1,%2,%2\n"
737 " stq_c %2,0(%4)\n"
738 " beq %2,3f\n"
739 "2:\n"
740 ".subsection 2\n"
741 "3: br 1b\n"
742 ".previous"
743 : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
744 : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
745
746 return prev;
747}
748
749static inline unsigned long
750__cmpxchg_u32_local(volatile int *m, int old, int new)
751{
752 unsigned long prev, cmp;
753
754 __asm__ __volatile__(
755 "1: ldl_l %0,%5\n"
756 " cmpeq %0,%3,%1\n"
757 " beq %1,2f\n"
758 " mov %4,%1\n"
759 " stl_c %1,%2\n"
760 " beq %1,3f\n"
761 "2:\n"
762 ".subsection 2\n"
763 "3: br 1b\n"
764 ".previous"
765 : "=&r"(prev), "=&r"(cmp), "=m"(*m)
766 : "r"((long) old), "r"(new), "m"(*m) : "memory");
767
768 return prev;
769}
770
771static inline unsigned long
772__cmpxchg_u64_local(volatile long *m, unsigned long old, unsigned long new)
773{
774 unsigned long prev, cmp;
775
776 __asm__ __volatile__(
777 "1: ldq_l %0,%5\n"
778 " cmpeq %0,%3,%1\n"
779 " beq %1,2f\n"
780 " mov %4,%1\n"
781 " stq_c %1,%2\n"
782 " beq %1,3f\n"
783 "2:\n"
784 ".subsection 2\n"
785 "3: br 1b\n"
786 ".previous"
787 : "=&r"(prev), "=&r"(cmp), "=m"(*m)
788 : "r"((long) old), "r"(new), "m"(*m) : "memory");
789
790 return prev;
791}
792
793static __always_inline unsigned long
794__cmpxchg_local(volatile void *ptr, unsigned long old, unsigned long new,
795 int size)
796{
797 switch (size) {
798 case 1:
799 return __cmpxchg_u8_local(ptr, old, new);
800 case 2:
801 return __cmpxchg_u16_local(ptr, old, new);
802 case 4:
803 return __cmpxchg_u32_local(ptr, old, new);
804 case 8:
805 return __cmpxchg_u64_local(ptr, old, new);
806 }
807 __cmpxchg_called_with_bad_pointer();
808 return old;
809}
810 358
811#define cmpxchg_local(ptr, o, n) \ 359#define cmpxchg(ptr, o, n) \
812 ({ \ 360 ({ \
813 __typeof__(*(ptr)) _o_ = (o); \ 361 __typeof__(*(ptr)) _o_ = (o); \
814 __typeof__(*(ptr)) _n_ = (n); \ 362 __typeof__(*(ptr)) _n_ = (n); \
815 (__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_, \ 363 (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
816 (unsigned long)_n_, sizeof(*(ptr))); \ 364 (unsigned long)_n_, sizeof(*(ptr)));\
817 }) 365 })
818#define cmpxchg64_local(ptr, o, n) \ 366
819 ({ \ 367#define cmpxchg64(ptr, o, n) \
820 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ 368 ({ \
821 cmpxchg_local((ptr), (o), (n)); \ 369 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
370 cmpxchg((ptr), (o), (n)); \
822 }) 371 })
823 372
373#undef __ASM__MB
374#undef ____cmpxchg
375
376#define __HAVE_ARCH_CMPXCHG 1
824 377
825#endif /* __ASSEMBLY__ */ 378#endif /* __ASSEMBLY__ */
826 379
diff --git a/arch/alpha/include/asm/xchg.h b/arch/alpha/include/asm/xchg.h
new file mode 100644
index 000000000000..beba1b803e0d
--- /dev/null
+++ b/arch/alpha/include/asm/xchg.h
@@ -0,0 +1,258 @@
1#ifndef __ALPHA_SYSTEM_H
2#error Do not include xchg.h directly!
3#else
4/*
5 * xchg/xchg_local and cmpxchg/cmpxchg_local share the same code
6 * except that local version do not have the expensive memory barrier.
7 * So this file is included twice from asm/system.h.
8 */
9
10/*
11 * Atomic exchange.
12 * Since it can be used to implement critical sections
13 * it must clobber "memory" (also for interrupts in UP).
14 */
15
16static inline unsigned long
17____xchg(_u8, volatile char *m, unsigned long val)
18{
19 unsigned long ret, tmp, addr64;
20
21 __asm__ __volatile__(
22 " andnot %4,7,%3\n"
23 " insbl %1,%4,%1\n"
24 "1: ldq_l %2,0(%3)\n"
25 " extbl %2,%4,%0\n"
26 " mskbl %2,%4,%2\n"
27 " or %1,%2,%2\n"
28 " stq_c %2,0(%3)\n"
29 " beq %2,2f\n"
30 __ASM__MB
31 ".subsection 2\n"
32 "2: br 1b\n"
33 ".previous"
34 : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
35 : "r" ((long)m), "1" (val) : "memory");
36
37 return ret;
38}
39
40static inline unsigned long
41____xchg(_u16, volatile short *m, unsigned long val)
42{
43 unsigned long ret, tmp, addr64;
44
45 __asm__ __volatile__(
46 " andnot %4,7,%3\n"
47 " inswl %1,%4,%1\n"
48 "1: ldq_l %2,0(%3)\n"
49 " extwl %2,%4,%0\n"
50 " mskwl %2,%4,%2\n"
51 " or %1,%2,%2\n"
52 " stq_c %2,0(%3)\n"
53 " beq %2,2f\n"
54 __ASM__MB
55 ".subsection 2\n"
56 "2: br 1b\n"
57 ".previous"
58 : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
59 : "r" ((long)m), "1" (val) : "memory");
60
61 return ret;
62}
63
64static inline unsigned long
65____xchg(_u32, volatile int *m, unsigned long val)
66{
67 unsigned long dummy;
68
69 __asm__ __volatile__(
70 "1: ldl_l %0,%4\n"
71 " bis $31,%3,%1\n"
72 " stl_c %1,%2\n"
73 " beq %1,2f\n"
74 __ASM__MB
75 ".subsection 2\n"
76 "2: br 1b\n"
77 ".previous"
78 : "=&r" (val), "=&r" (dummy), "=m" (*m)
79 : "rI" (val), "m" (*m) : "memory");
80
81 return val;
82}
83
84static inline unsigned long
85____xchg(_u64, volatile long *m, unsigned long val)
86{
87 unsigned long dummy;
88
89 __asm__ __volatile__(
90 "1: ldq_l %0,%4\n"
91 " bis $31,%3,%1\n"
92 " stq_c %1,%2\n"
93 " beq %1,2f\n"
94 __ASM__MB
95 ".subsection 2\n"
96 "2: br 1b\n"
97 ".previous"
98 : "=&r" (val), "=&r" (dummy), "=m" (*m)
99 : "rI" (val), "m" (*m) : "memory");
100
101 return val;
102}
103
104/* This function doesn't exist, so you'll get a linker error
105 if something tries to do an invalid xchg(). */
106extern void __xchg_called_with_bad_pointer(void);
107
108static __always_inline unsigned long
109____xchg(, volatile void *ptr, unsigned long x, int size)
110{
111 switch (size) {
112 case 1:
113 return ____xchg(_u8, ptr, x);
114 case 2:
115 return ____xchg(_u16, ptr, x);
116 case 4:
117 return ____xchg(_u32, ptr, x);
118 case 8:
119 return ____xchg(_u64, ptr, x);
120 }
121 __xchg_called_with_bad_pointer();
122 return x;
123}
124
125/*
126 * Atomic compare and exchange. Compare OLD with MEM, if identical,
127 * store NEW in MEM. Return the initial value in MEM. Success is
128 * indicated by comparing RETURN with OLD.
129 *
130 * The memory barrier should be placed in SMP only when we actually
131 * make the change. If we don't change anything (so if the returned
132 * prev is equal to old) then we aren't acquiring anything new and
133 * we don't need any memory barrier as far I can tell.
134 */
135
136static inline unsigned long
137____cmpxchg(_u8, volatile char *m, unsigned char old, unsigned char new)
138{
139 unsigned long prev, tmp, cmp, addr64;
140
141 __asm__ __volatile__(
142 " andnot %5,7,%4\n"
143 " insbl %1,%5,%1\n"
144 "1: ldq_l %2,0(%4)\n"
145 " extbl %2,%5,%0\n"
146 " cmpeq %0,%6,%3\n"
147 " beq %3,2f\n"
148 " mskbl %2,%5,%2\n"
149 " or %1,%2,%2\n"
150 " stq_c %2,0(%4)\n"
151 " beq %2,3f\n"
152 __ASM__MB
153 "2:\n"
154 ".subsection 2\n"
155 "3: br 1b\n"
156 ".previous"
157 : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
158 : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
159
160 return prev;
161}
162
163static inline unsigned long
164____cmpxchg(_u16, volatile short *m, unsigned short old, unsigned short new)
165{
166 unsigned long prev, tmp, cmp, addr64;
167
168 __asm__ __volatile__(
169 " andnot %5,7,%4\n"
170 " inswl %1,%5,%1\n"
171 "1: ldq_l %2,0(%4)\n"
172 " extwl %2,%5,%0\n"
173 " cmpeq %0,%6,%3\n"
174 " beq %3,2f\n"
175 " mskwl %2,%5,%2\n"
176 " or %1,%2,%2\n"
177 " stq_c %2,0(%4)\n"
178 " beq %2,3f\n"
179 __ASM__MB
180 "2:\n"
181 ".subsection 2\n"
182 "3: br 1b\n"
183 ".previous"
184 : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
185 : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
186
187 return prev;
188}
189
190static inline unsigned long
191____cmpxchg(_u32, volatile int *m, int old, int new)
192{
193 unsigned long prev, cmp;
194
195 __asm__ __volatile__(
196 "1: ldl_l %0,%5\n"
197 " cmpeq %0,%3,%1\n"
198 " beq %1,2f\n"
199 " mov %4,%1\n"
200 " stl_c %1,%2\n"
201 " beq %1,3f\n"
202 __ASM__MB
203 "2:\n"
204 ".subsection 2\n"
205 "3: br 1b\n"
206 ".previous"
207 : "=&r"(prev), "=&r"(cmp), "=m"(*m)
208 : "r"((long) old), "r"(new), "m"(*m) : "memory");
209
210 return prev;
211}
212
213static inline unsigned long
214____cmpxchg(_u64, volatile long *m, unsigned long old, unsigned long new)
215{
216 unsigned long prev, cmp;
217
218 __asm__ __volatile__(
219 "1: ldq_l %0,%5\n"
220 " cmpeq %0,%3,%1\n"
221 " beq %1,2f\n"
222 " mov %4,%1\n"
223 " stq_c %1,%2\n"
224 " beq %1,3f\n"
225 __ASM__MB
226 "2:\n"
227 ".subsection 2\n"
228 "3: br 1b\n"
229 ".previous"
230 : "=&r"(prev), "=&r"(cmp), "=m"(*m)
231 : "r"((long) old), "r"(new), "m"(*m) : "memory");
232
233 return prev;
234}
235
236/* This function doesn't exist, so you'll get a linker error
237 if something tries to do an invalid cmpxchg(). */
238extern void __cmpxchg_called_with_bad_pointer(void);
239
240static __always_inline unsigned long
241____cmpxchg(, volatile void *ptr, unsigned long old, unsigned long new,
242 int size)
243{
244 switch (size) {
245 case 1:
246 return ____cmpxchg(_u8, ptr, old, new);
247 case 2:
248 return ____cmpxchg(_u16, ptr, old, new);
249 case 4:
250 return ____cmpxchg(_u32, ptr, old, new);
251 case 8:
252 return ____cmpxchg(_u64, ptr, old, new);
253 }
254 __cmpxchg_called_with_bad_pointer();
255 return old;
256}
257
258#endif
generated by cgit v1.2.2 (git 2.25.0) at 2024-09-20 09:15:19 -0400