On 04/20/2016 07:01 AM, Alex Bennée wrote:
Sergey Fedorov <sergey.fedo...@linaro.org> writes:From: Sergey Fedorov <serge.f...@gmail.com> Ensure direct jump patching in AArch64 is atomic by using atomic_read()/atomic_set() for code patching. Signed-off-by: Sergey Fedorov <serge.f...@gmail.com> Signed-off-by: Sergey Fedorov <sergey.fedo...@linaro.org> --- tcg/aarch64/tcg-target.inc.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/tcg/aarch64/tcg-target.inc.c b/tcg/aarch64/tcg-target.inc.c index 0ed10a974121..15fdebec921f 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; + assert(offset == sextract64(offset, 0, 26)); + /* read instruction, mask away previous PC_REL26 parameter contents, + set the proper offset, then write back the instruction. */This comment could be moved from here and reloc_pc26 and made common for the two following functions.
There's a significant amount of cleanup that ought to happen here, now that we're not re-translating TBs. I don't know if Sergey should be gated on that.
r~
