| /* SPDX-License-Identifier: LGPL-2.1 OR MIT */ |
| /* |
| * Author: Paul Burton <paul.burton@mips.com> |
| * (C) Copyright 2018 MIPS Tech LLC |
| * (C) Copyright 2016-2022 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| */ |
| |
| /* |
| * RSEQ_SIG uses the break instruction. The instruction pattern is: |
| * |
| * On MIPS: |
| * 0350000d break 0x350 |
| * |
| * On nanoMIPS: |
| * 00100350 break 0x350 |
| * |
| * On microMIPS: |
| * 0000d407 break 0x350 |
| * |
| * For nanoMIPS32 and microMIPS, the instruction stream is encoded as 16-bit |
| * halfwords, so the signature halfwords need to be swapped accordingly for |
| * little-endian. |
| */ |
| #if defined(__nanomips__) |
| # ifdef __MIPSEL__ |
| # define RSEQ_SIG 0x03500010 |
| # else |
| # define RSEQ_SIG 0x00100350 |
| # endif |
| #elif defined(__mips_micromips) |
| # ifdef __MIPSEL__ |
| # define RSEQ_SIG 0xd4070000 |
| # else |
| # define RSEQ_SIG 0x0000d407 |
| # endif |
| #elif defined(__mips__) |
| # define RSEQ_SIG 0x0350000d |
| #else |
| /* Unknown MIPS architecture. */ |
| #endif |
| |
| #define rseq_smp_mb() __asm__ __volatile__ ("sync" ::: "memory") |
| #define rseq_smp_rmb() rseq_smp_mb() |
| #define rseq_smp_wmb() rseq_smp_mb() |
| |
| #define rseq_smp_load_acquire(p) \ |
| __extension__ ({ \ |
| rseq_unqual_scalar_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) |
| |
| #if _MIPS_SZLONG == 64 |
| # define LONG ".dword" |
| # define LONG_LA "dla" |
| # define LONG_L "ld" |
| # define LONG_S "sd" |
| # define LONG_ADDI "daddiu" |
| # define U32_U64_PAD(x) x |
| #elif _MIPS_SZLONG == 32 |
| # define LONG ".word" |
| # define LONG_LA "la" |
| # define LONG_L "lw" |
| # define LONG_S "sw" |
| # define LONG_ADDI "addiu" |
| # ifdef __BIG_ENDIAN |
| # define U32_U64_PAD(x) "0x0, " x |
| # else |
| # define U32_U64_PAD(x) x ", 0x0" |
| # endif |
| #else |
| # error unsupported _MIPS_SZLONG |
| #endif |
| |
| #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" \ |
| ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ |
| LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \ |
| LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \ |
| LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \ |
| ".popsection\n\t" \ |
| ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ |
| LONG " " U32_U64_PAD(__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" \ |
| LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \ |
| LONG " " U32_U64_PAD(__rseq_str(exit_ip)) "\n\t" \ |
| ".popsection\n\t" |
| |
| #define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ |
| RSEQ_INJECT_ASM(1) \ |
| LONG_LA " $4, " __rseq_str(cs_label) "\n\t" \ |
| LONG_S " $4, %[" __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) \ |
| "lw $4, %[" __rseq_str(current_cpu_id) "]\n\t" \ |
| "bne $4, %[" __rseq_str(cpu_id) "], " __rseq_str(label) "\n\t" |
| |
| #define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \ |
| abort_label, version, flags, \ |
| start_ip, post_commit_offset, abort_ip) \ |
| ".balign 32\n\t" \ |
| __rseq_str(table_label) ":\n\t" \ |
| ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ |
| LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \ |
| LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \ |
| LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \ |
| ".word " __rseq_str(RSEQ_SIG) "\n\t" \ |
| __rseq_str(label) ":\n\t" \ |
| teardown \ |
| "b %l[" __rseq_str(abort_label) "]\n\t" |
| |
| #define RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, abort_label, \ |
| start_ip, post_commit_ip, abort_ip) \ |
| __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \ |
| abort_label, 0x0, 0x0, start_ip, \ |
| (post_commit_ip - start_ip), abort_ip) |
| |
| #define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \ |
| __rseq_str(label) ":\n\t" \ |
| teardown \ |
| "b %l[" __rseq_str(cmpfail_label) "]\n\t" |
| |
| /* Per-cpu-id indexing. */ |
| |
| #define RSEQ_TEMPLATE_CPU_ID |
| #define RSEQ_TEMPLATE_MO_RELAXED |
| #include "rseq-mips-bits.h" |
| #undef RSEQ_TEMPLATE_MO_RELAXED |
| |
| #define RSEQ_TEMPLATE_MO_RELEASE |
| #include "rseq-mips-bits.h" |
| #undef RSEQ_TEMPLATE_MO_RELEASE |
| #undef RSEQ_TEMPLATE_CPU_ID |
| |
| /* Per-mm-cid indexing. */ |
| |
| #define RSEQ_TEMPLATE_MM_CID |
| #define RSEQ_TEMPLATE_MO_RELAXED |
| #include "rseq-mips-bits.h" |
| #undef RSEQ_TEMPLATE_MO_RELAXED |
| |
| #define RSEQ_TEMPLATE_MO_RELEASE |
| #include "rseq-mips-bits.h" |
| #undef RSEQ_TEMPLATE_MO_RELEASE |
| #undef RSEQ_TEMPLATE_MM_CID |
| |
| /* APIs which are not based on cpu ids. */ |
| |
| #define RSEQ_TEMPLATE_CPU_ID_NONE |
| #define RSEQ_TEMPLATE_MO_RELAXED |
| #include "rseq-mips-bits.h" |
| #undef RSEQ_TEMPLATE_MO_RELAXED |
| #undef RSEQ_TEMPLATE_CPU_ID_NONE |