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Diffstat (limited to '')
-rw-r--r-- | tools/testing/selftests/rseq/rseq-x86.h | 1365 |
1 files changed, 1365 insertions, 0 deletions
diff --git a/tools/testing/selftests/rseq/rseq-x86.h b/tools/testing/selftests/rseq/rseq-x86.h new file mode 100644 index 000000000..bd01dc41c --- /dev/null +++ b/tools/testing/selftests/rseq/rseq-x86.h @@ -0,0 +1,1365 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * rseq-x86.h + * + * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> + */ + +#include <stdint.h> + +/* + * RSEQ_SIG is used with the following reserved undefined instructions, which + * trap in user-space: + * + * x86-32: 0f b9 3d 53 30 05 53 ud1 0x53053053,%edi + * x86-64: 0f b9 3d 53 30 05 53 ud1 0x53053053(%rip),%edi + */ +#define RSEQ_SIG 0x53053053 + +/* + * Due to a compiler optimization bug in gcc-8 with asm goto and TLS asm input + * operands, we cannot use "m" input operands, and rather pass the __rseq_abi + * address through a "r" input operand. + */ + +/* Offset of cpu_id and rseq_cs fields in struct rseq. */ +#define RSEQ_CPU_ID_OFFSET 4 +#define RSEQ_CS_OFFSET 8 + +#ifdef __x86_64__ + +#define RSEQ_ASM_TP_SEGMENT %%fs + +#define rseq_smp_mb() \ + __asm__ __volatile__ ("lock; addl $0,-128(%%rsp)" ::: "memory", "cc") +#define rseq_smp_rmb() rseq_barrier() +#define rseq_smp_wmb() rseq_barrier() + +#define rseq_smp_load_acquire(p) \ +__extension__ ({ \ + __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ + rseq_barrier(); \ + ____p1; \ +}) + +#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb() + +#define rseq_smp_store_release(p, v) \ +do { \ + rseq_barrier(); \ + RSEQ_WRITE_ONCE(*p, v); \ +} while (0) + +#ifdef RSEQ_SKIP_FASTPATH +#include "rseq-skip.h" +#else /* !RSEQ_SKIP_FASTPATH */ + +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ + start_ip, post_commit_offset, abort_ip) \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ + ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ + ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".quad " __rseq_str(label) "b\n\t" \ + ".popsection\n\t" + + +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +/* + * Exit points of a rseq critical section consist of all instructions outside + * of the critical section where a critical section can either branch to or + * reach through the normal course of its execution. The abort IP and the + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is + * useful to assist debuggers stepping over the critical section. + */ +#define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ + ".pushsection __rseq_exit_point_array, \"aw\"\n\t" \ + ".quad " __rseq_str(start_ip) ", " __rseq_str(exit_ip) "\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "leaq " __rseq_str(cs_label) "(%%rip), %%rax\n\t" \ + "movq %%rax, " __rseq_str(rseq_cs) "\n\t" \ + __rseq_str(label) ":\n\t" + +#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ + RSEQ_INJECT_ASM(2) \ + "cmpl %[" __rseq_str(cpu_id) "], " __rseq_str(current_cpu_id) "\n\t" \ + "jnz " __rseq_str(label) "\n\t" + +#define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + /* Disassembler-friendly signature: ud1 <sig>(%rip),%edi. */ \ + ".byte 0x0f, 0xb9, 0x3d\n\t" \ + ".long " __rseq_str(RSEQ_SIG) "\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "jmp %l[" __rseq_str(abort_label) "]\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "jmp %l[" __rseq_str(cmpfail_label) "]\n\t" \ + ".popsection\n\t" + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "cmpq %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "cmpq %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" +#endif + /* final store */ + "movq %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +/* + * Compare @v against @expectnot. When it does _not_ match, load @v + * into @load, and store the content of *@v + voffp into @v. + */ +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + long voffp, intptr_t *load, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "movq %[v], %%rbx\n\t" + "cmpq %%rbx, %[expectnot]\n\t" + "je %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "movq %[v], %%rbx\n\t" + "cmpq %%rbx, %[expectnot]\n\t" + "je %l[error2]\n\t" +#endif + "movq %%rbx, %[load]\n\t" + "addq %[voffp], %%rbx\n\t" + "movq (%%rbx), %%rbx\n\t" + /* final store */ + "movq %%rbx, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* final store input */ + [v] "m" (*v), + [expectnot] "r" (expectnot), + [voffp] "er" (voffp), + [load] "m" (*load) + : "memory", "cc", "rax", "rbx" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) +#endif + /* final store */ + "addq %[count], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(4) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* final store input */ + [v] "m" (*v), + [count] "er" (count) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +#endif +} + +#define RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV + +/* + * pval = *(ptr+off) + * *pval += inc; + */ +static inline __attribute__((always_inline)) +int rseq_offset_deref_addv(intptr_t *ptr, long off, intptr_t inc, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) +#endif + /* get p+v */ + "movq %[ptr], %%rbx\n\t" + "addq %[off], %%rbx\n\t" + /* get pv */ + "movq (%%rbx), %%rcx\n\t" + /* *pv += inc */ + "addq %[inc], (%%rcx)\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(4) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* final store input */ + [ptr] "m" (*ptr), + [off] "er" (off), + [inc] "er" (inc) + : "memory", "cc", "rax", "rbx", "rcx" + RSEQ_INJECT_CLOBBER + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + return 0; +abort: + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_bug("cpu_id comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "cmpq %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "cmpq %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" +#endif + /* try store */ + "movq %[newv2], %[v2]\n\t" + RSEQ_INJECT_ASM(5) + /* final store */ + "movq %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +/* x86-64 is TSO. */ +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + return rseq_cmpeqv_trystorev_storev(v, expect, v2, newv2, newv, cpu); +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error3]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "cmpq %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) + "cmpq %[v2], %[expect2]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(5) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "cmpq %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" + "cmpq %[v2], %[expect2]\n\t" + "jnz %l[error3]\n\t" +#endif + /* final store */ + "movq %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* cmp2 input */ + [v2] "m" (*v2), + [expect2] "r" (expect2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2, error3 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("1st expected value comparison failed"); +error3: + rseq_after_asm_goto(); + rseq_bug("2nd expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint64_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + "movq %[src], %[rseq_scratch0]\n\t" + "movq %[dst], %[rseq_scratch1]\n\t" + "movq %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "cmpq %[v], %[expect]\n\t" + "jnz 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 6f) + "cmpq %[v], %[expect]\n\t" + "jnz 7f\n\t" +#endif + /* try memcpy */ + "test %[len], %[len]\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "movb (%[src]), %%al\n\t" \ + "movb %%al, (%[dst])\n\t" \ + "inc %[src]\n\t" \ + "inc %[dst]\n\t" \ + "dec %[len]\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + /* final store */ + "movq %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t" + RSEQ_ASM_DEFINE_ABORT(4, + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t", + abort) + RSEQ_ASM_DEFINE_CMPFAIL(5, + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + "movq %[rseq_scratch2], %[len]\n\t" + "movq %[rseq_scratch1], %[dst]\n\t" + "movq %[rseq_scratch0], %[src]\n\t", + error2) +#endif + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + : "memory", "cc", "rax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +/* x86-64 is TSO. */ +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + return rseq_cmpeqv_trymemcpy_storev(v, expect, dst, src, len, + newv, cpu); +} + +#endif /* !RSEQ_SKIP_FASTPATH */ + +#elif defined(__i386__) + +#define RSEQ_ASM_TP_SEGMENT %%gs + +#define rseq_smp_mb() \ + __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc") +#define rseq_smp_rmb() \ + __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc") +#define rseq_smp_wmb() \ + __asm__ __volatile__ ("lock; addl $0,-128(%%esp)" ::: "memory", "cc") + +#define rseq_smp_load_acquire(p) \ +__extension__ ({ \ + __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ + rseq_smp_mb(); \ + ____p1; \ +}) + +#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb() + +#define rseq_smp_store_release(p, v) \ +do { \ + rseq_smp_mb(); \ + RSEQ_WRITE_ONCE(*p, v); \ +} while (0) + +#ifdef RSEQ_SKIP_FASTPATH +#include "rseq-skip.h" +#else /* !RSEQ_SKIP_FASTPATH */ + +/* + * Use eax as scratch register and take memory operands as input to + * lessen register pressure. Especially needed when compiling in O0. + */ +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ + start_ip, post_commit_offset, abort_ip) \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ + ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ + ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".long " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".long " __rseq_str(label) "b, 0x0\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +/* + * Exit points of a rseq critical section consist of all instructions outside + * of the critical section where a critical section can either branch to or + * reach through the normal course of its execution. The abort IP and the + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is + * useful to assist debuggers stepping over the critical section. + */ +#define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ + ".pushsection __rseq_exit_point_array, \"aw\"\n\t" \ + ".long " __rseq_str(start_ip) ", 0x0, " __rseq_str(exit_ip) ", 0x0\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "movl $" __rseq_str(cs_label) ", " __rseq_str(rseq_cs) "\n\t" \ + __rseq_str(label) ":\n\t" + +#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ + RSEQ_INJECT_ASM(2) \ + "cmpl %[" __rseq_str(cpu_id) "], " __rseq_str(current_cpu_id) "\n\t" \ + "jnz " __rseq_str(label) "\n\t" + +#define RSEQ_ASM_DEFINE_ABORT(label, teardown, abort_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + /* Disassembler-friendly signature: ud1 <sig>,%edi. */ \ + ".byte 0x0f, 0xb9, 0x3d\n\t" \ + ".long " __rseq_str(RSEQ_SIG) "\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "jmp %l[" __rseq_str(abort_label) "]\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \ + ".pushsection __rseq_failure, \"ax\"\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "jmp %l[" __rseq_str(cmpfail_label) "]\n\t" \ + ".popsection\n\t" + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "cmpl %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "cmpl %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" +#endif + /* final store */ + "movl %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +/* + * Compare @v against @expectnot. When it does _not_ match, load @v + * into @load, and store the content of *@v + voffp into @v. + */ +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + long voffp, intptr_t *load, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "movl %[v], %%ebx\n\t" + "cmpl %%ebx, %[expectnot]\n\t" + "je %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "movl %[v], %%ebx\n\t" + "cmpl %%ebx, %[expectnot]\n\t" + "je %l[error2]\n\t" +#endif + "movl %%ebx, %[load]\n\t" + "addl %[voffp], %%ebx\n\t" + "movl (%%ebx), %%ebx\n\t" + /* final store */ + "movl %%ebx, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* final store input */ + [v] "m" (*v), + [expectnot] "r" (expectnot), + [voffp] "ir" (voffp), + [load] "m" (*load) + : "memory", "cc", "eax", "ebx" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) +#endif + /* final store */ + "addl %[count], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(4) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* final store input */ + [v] "m" (*v), + [count] "ir" (count) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "cmpl %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "cmpl %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" +#endif + /* try store */ + "movl %[newv2], %%eax\n\t" + "movl %%eax, %[v2]\n\t" + RSEQ_INJECT_ASM(5) + /* final store */ + "movl %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* try store input */ + [v2] "m" (*v2), + [newv2] "m" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "movl %[expect], %%eax\n\t" + "cmpl %[v], %%eax\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "movl %[expect], %%eax\n\t" + "cmpl %[v], %%eax\n\t" + "jnz %l[error2]\n\t" +#endif + /* try store */ + "movl %[newv2], %[v2]\n\t" + RSEQ_INJECT_ASM(5) + "lock; addl $0,-128(%%esp)\n\t" + /* final store */ + "movl %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "m" (expect), + [newv] "r" (newv) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif + +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error3]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "cmpl %[v], %[expect]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) + "cmpl %[expect2], %[v2]\n\t" + "jnz %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(5) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), %l[error1]) + "cmpl %[v], %[expect]\n\t" + "jnz %l[error2]\n\t" + "cmpl %[expect2], %[v2]\n\t" + "jnz %l[error3]\n\t" +#endif + "movl %[newv], %%eax\n\t" + /* final store */ + "movl %%eax, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + RSEQ_ASM_DEFINE_ABORT(4, "", abort) + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* cmp2 input */ + [v2] "m" (*v2), + [expect2] "r" (expect2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "m" (newv) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2, error3 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("1st expected value comparison failed"); +error3: + rseq_after_asm_goto(); + rseq_bug("2nd expected value comparison failed"); +#endif +} + +/* TODO: implement a faster memcpy. */ +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint32_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + "movl %[src], %[rseq_scratch0]\n\t" + "movl %[dst], %[rseq_scratch1]\n\t" + "movl %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "movl %[expect], %%eax\n\t" + "cmpl %%eax, %[v]\n\t" + "jnz 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 6f) + "movl %[expect], %%eax\n\t" + "cmpl %%eax, %[v]\n\t" + "jnz 7f\n\t" +#endif + /* try memcpy */ + "test %[len], %[len]\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "movb (%[src]), %%al\n\t" \ + "movb %%al, (%[dst])\n\t" \ + "inc %[src]\n\t" \ + "inc %[dst]\n\t" \ + "dec %[len]\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + "movl %[newv], %%eax\n\t" + /* final store */ + "movl %%eax, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t" + RSEQ_ASM_DEFINE_ABORT(4, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + abort) + RSEQ_ASM_DEFINE_CMPFAIL(5, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + error2) +#endif + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* final store input */ + [v] "m" (*v), + [expect] "m" (expect), + [newv] "m" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +/* TODO: implement a faster memcpy. */ +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint32_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(3, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + "movl %[src], %[rseq_scratch0]\n\t" + "movl %[dst], %[rseq_scratch1]\n\t" + "movl %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3b, RSEQ_ASM_TP_SEGMENT:RSEQ_CS_OFFSET(%[rseq_offset])) + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 4f) + RSEQ_INJECT_ASM(3) + "movl %[expect], %%eax\n\t" + "cmpl %%eax, %[v]\n\t" + "jnz 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, RSEQ_ASM_TP_SEGMENT:RSEQ_CPU_ID_OFFSET(%[rseq_offset]), 6f) + "movl %[expect], %%eax\n\t" + "cmpl %%eax, %[v]\n\t" + "jnz 7f\n\t" +#endif + /* try memcpy */ + "test %[len], %[len]\n\t" \ + "jz 333f\n\t" \ + "222:\n\t" \ + "movb (%[src]), %%al\n\t" \ + "movb %%al, (%[dst])\n\t" \ + "inc %[src]\n\t" \ + "inc %[dst]\n\t" \ + "dec %[len]\n\t" \ + "jnz 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + "lock; addl $0,-128(%%esp)\n\t" + "movl %[newv], %%eax\n\t" + /* final store */ + "movl %%eax, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t" + RSEQ_ASM_DEFINE_ABORT(4, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + abort) + RSEQ_ASM_DEFINE_CMPFAIL(5, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + "movl %[rseq_scratch2], %[len]\n\t" + "movl %[rseq_scratch1], %[dst]\n\t" + "movl %[rseq_scratch0], %[src]\n\t", + error2) +#endif + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [rseq_offset] "r" (rseq_offset), + /* final store input */ + [v] "m" (*v), + [expect] "m" (expect), + [newv] "m" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + : "memory", "cc", "eax" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +#endif /* !RSEQ_SKIP_FASTPATH */ + +#endif |