blob: 42ef8e946693f139ba9c8f8a7f86eb30412759f6 [file] [log] [blame]
/* 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