diff options
| author | Sergey Fedorov <serge.fdrv@gmail.com> | 2016-04-22 19:08:50 +0300 |
|---|---|---|
| committer | Richard Henderson <rth@twiddle.net> | 2016-05-12 14:06:41 -1000 |
| commit | 9e269112953be4d670cb0d25042bd6546fcf3e45 (patch) | |
| tree | 5fee12d3d27049af5e883e2026be6e336c93b7de | |
| parent | 7d14e0e2d661479985197203589c38840e1066df (diff) | |
tcg/aarch64: Make direct jump patching thread-safe
Ensure direct jump patching in AArch64 is atomic by using
atomic_read()/atomic_set() for code patching.
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Message-Id: <1461341333-19646-9-git-send-email-sergey.fedorov@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
| -rw-r--r-- | tcg/aarch64/tcg-target.inc.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/tcg/aarch64/tcg-target.inc.c b/tcg/aarch64/tcg-target.inc.c index a8fb4420de..88183c830f 100644 --- a/tcg/aarch64/tcg-target.inc.c +++ b/tcg/aarch64/tcg-target.inc.c @@ -73,6 +73,18 @@ static inline void reloc_pc26(tcg_insn_unit *code_ptr, tcg_insn_unit *target) *code_ptr = deposit32(*code_ptr, 0, 26, offset); } +static inline void reloc_pc26_atomic(tcg_insn_unit *code_ptr, + tcg_insn_unit *target) +{ + ptrdiff_t offset = target - code_ptr; + tcg_insn_unit insn; + tcg_debug_assert(offset == sextract64(offset, 0, 26)); + /* read instruction, mask away previous PC_REL26 parameter contents, + set the proper offset, then write back the instruction. */ + insn = atomic_read(code_ptr); + atomic_set(code_ptr, deposit32(insn, 0, 26, offset)); +} + static inline void reloc_pc19(tcg_insn_unit *code_ptr, tcg_insn_unit *target) { ptrdiff_t offset = target - code_ptr; @@ -835,7 +847,7 @@ void aarch64_tb_set_jmp_target(uintptr_t jmp_addr, uintptr_t addr) tcg_insn_unit *code_ptr = (tcg_insn_unit *)jmp_addr; tcg_insn_unit *target = (tcg_insn_unit *)addr; - reloc_pc26(code_ptr, target); + reloc_pc26_atomic(code_ptr, target); flush_icache_range(jmp_addr, jmp_addr + 4); } |