1/* atomic.S: These things are too big to do inline. 2 * 3 * Copyright (C) 1999, 2007 2012 David S. Miller (davem@davemloft.net) 4 */ 5 6#include <linux/linkage.h> 7#include <asm/asi.h> 8#include <asm/backoff.h> 9 10 .text 11 12 /* Two versions of the atomic routines, one that 13 * does not return a value and does not perform 14 * memory barriers, and a second which returns 15 * a value and does the barriers. 16 */ 17 18#define ATOMIC_OP(op) \ 19ENTRY(atomic_##op) /* %o0 = increment, %o1 = atomic_ptr */ \ 20 BACKOFF_SETUP(%o2); \ 211: lduw [%o1], %g1; \ 22 op %g1, %o0, %g7; \ 23 cas [%o1], %g1, %g7; \ 24 cmp %g1, %g7; \ 25 bne,pn %icc, BACKOFF_LABEL(2f, 1b); \ 26 nop; \ 27 retl; \ 28 nop; \ 292: BACKOFF_SPIN(%o2, %o3, 1b); \ 30ENDPROC(atomic_##op); \ 31 32#define ATOMIC_OP_RETURN(op) \ 33ENTRY(atomic_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */ \ 34 BACKOFF_SETUP(%o2); \ 351: lduw [%o1], %g1; \ 36 op %g1, %o0, %g7; \ 37 cas [%o1], %g1, %g7; \ 38 cmp %g1, %g7; \ 39 bne,pn %icc, BACKOFF_LABEL(2f, 1b); \ 40 op %g1, %o0, %g1; \ 41 retl; \ 42 sra %g1, 0, %o0; \ 432: BACKOFF_SPIN(%o2, %o3, 1b); \ 44ENDPROC(atomic_##op##_return); 45 46#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) 47 48ATOMIC_OPS(add) 49ATOMIC_OPS(sub) 50ATOMIC_OP(and) 51ATOMIC_OP(or) 52ATOMIC_OP(xor) 53 54#undef ATOMIC_OPS 55#undef ATOMIC_OP_RETURN 56#undef ATOMIC_OP 57 58#define ATOMIC64_OP(op) \ 59ENTRY(atomic64_##op) /* %o0 = increment, %o1 = atomic_ptr */ \ 60 BACKOFF_SETUP(%o2); \ 611: ldx [%o1], %g1; \ 62 op %g1, %o0, %g7; \ 63 casx [%o1], %g1, %g7; \ 64 cmp %g1, %g7; \ 65 bne,pn %xcc, BACKOFF_LABEL(2f, 1b); \ 66 nop; \ 67 retl; \ 68 nop; \ 692: BACKOFF_SPIN(%o2, %o3, 1b); \ 70ENDPROC(atomic64_##op); \ 71 72#define ATOMIC64_OP_RETURN(op) \ 73ENTRY(atomic64_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */ \ 74 BACKOFF_SETUP(%o2); \ 751: ldx [%o1], %g1; \ 76 op %g1, %o0, %g7; \ 77 casx [%o1], %g1, %g7; \ 78 cmp %g1, %g7; \ 79 bne,pn %xcc, BACKOFF_LABEL(2f, 1b); \ 80 nop; \ 81 retl; \ 82 op %g1, %o0, %o0; \ 832: BACKOFF_SPIN(%o2, %o3, 1b); \ 84ENDPROC(atomic64_##op##_return); 85 86#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op) 87 88ATOMIC64_OPS(add) 89ATOMIC64_OPS(sub) 90ATOMIC64_OP(and) 91ATOMIC64_OP(or) 92ATOMIC64_OP(xor) 93 94#undef ATOMIC64_OPS 95#undef ATOMIC64_OP_RETURN 96#undef ATOMIC64_OP 97 98ENTRY(atomic64_dec_if_positive) /* %o0 = atomic_ptr */ 99 BACKOFF_SETUP(%o2) 1001: ldx [%o0], %g1 101 brlez,pn %g1, 3f 102 sub %g1, 1, %g7 103 casx [%o0], %g1, %g7 104 cmp %g1, %g7 105 bne,pn %xcc, BACKOFF_LABEL(2f, 1b) 106 nop 1073: retl 108 sub %g1, 1, %o0 1092: BACKOFF_SPIN(%o2, %o3, 1b) 110ENDPROC(atomic64_dec_if_positive) 111