On 29/01/2017 22:09, Paolo Bonzini wrote: > The series includes three parts: > > 1-2: fix two bugs, the first one pretty bad, the second seems > to be theoretical only. > > 3-5: simplify cpu_exec. This builds on Sergey's conversion > of cpu_exec to a simple top-down logic, making the phases > clearer and saving on the cost of siglongjmp in the meanwhile.
I'll include these five in my next pull request. Review for patch 6 is welcome! Paolo > 6-7: these are intended to be a base for Pavel's record/replay > fixes. The main thing I noticed while reviewing is that icount > is redoing (with u16.high) a lot of things that tcg_exit_req is > doing too. This is because, at the time icount was introduced, > tcg_exit_req didn't exist and QEMU instead unwound chained TBs > through POSIX signals. But now we have essentially two ways to > do the same thing with subtly different invariants or downright > bugs (such as the one fixed by patch 1). Patch 6 therefore > unifies tcg_exit_req and the icount interrupt flag. It saves a > handful of instructions per TB in icount mode and generally > makes icount mode "less special", which is a good thing since > no one seems to understand it well. Patch 7 then removes another > EXCP_INTERRUPT/cpu_loop_exit pair; by exiting to main loop simply > through cpu->exit_request, hopefully it fixes one of the issues that > Pavel was seeing. > > For now I've tested this only on an aarch64 Linux image (with > and without -icount). Thanks, > > Paolo > > Paolo Bonzini (7): > cpu-exec: fix jmp_first out-of-bounds access with icount > cpu-exec: tighten barrier on TCG_EXIT_REQUESTED > cpu-exec: avoid cpu_loop_exit in cpu_handle_interrupt > cpu-exec: avoid repeated sigsetjmp on interrupts > cpu-exec: remove outermost infinite loop > cpu-exec: unify icount_decr and tcg_exit_req > cpu-exec: centralize exiting to the main loop > > cpu-exec.c | 153 > +++++++++++++++++++++------------------------- > include/exec/exec-all.h | 1 + > include/exec/gen-icount.h | 53 ++++++++-------- > include/qom/cpu.h | 15 +++-- > qom/cpu.c | 2 +- > tcg/tcg.h | 1 - > translate-all.c | 2 +- > translate-common.c | 13 ++-- > 8 files changed, 109 insertions(+), 131 deletions(-) >
