On 31/07/20 14:51, Robert Foley wrote: > This change removes the implied BQL from the cpu_handle_interrupt, > and cpu_handle_exception paths. We can now select per-arch if > the BQL is needed or not by using the bql_interrupt flag. > By default, the core code holds the BQL. > One benefit of this change is that it leaves it up to the arch > to make the change to remove BQL when it makes sense. > > Signed-off-by: Robert Foley <robert.fo...@linaro.org>
No, please just modify all implementation to do lock/unlock. It's a simpler patch than this on. Paolo > --- > accel/tcg/cpu-exec.c | 34 ++++++++++++++++++++++++++-------- > 1 file changed, 26 insertions(+), 8 deletions(-) > > diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c > index 80d0e649b2..cde27ee0bf 100644 > --- a/accel/tcg/cpu-exec.c > +++ b/accel/tcg/cpu-exec.c > @@ -517,9 +517,13 @@ static inline bool cpu_handle_exception(CPUState *cpu, > int *ret) > #else > if (replay_exception()) { > CPUClass *cc = CPU_GET_CLASS(cpu); > - qemu_mutex_lock_iothread(); > + if (cc->bql_interrupt) { > + qemu_mutex_lock_iothread(); > + } > cc->do_interrupt(cpu); > - qemu_mutex_unlock_iothread(); > + if (cc->bql_interrupt) { > + qemu_mutex_unlock_iothread(); > + } > cpu->exception_index = -1; > > if (unlikely(cpu->singlestep_enabled)) { > @@ -558,7 +562,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, > if (unlikely(cpu_interrupt_request(cpu))) { > int interrupt_request; > > - qemu_mutex_lock_iothread(); > + cpu_mutex_lock(cpu); > interrupt_request = cpu_interrupt_request(cpu); > if (unlikely(cpu->singlestep_enabled & SSTEP_NOIRQ)) { > /* Mask out external interrupts for this step. */ > @@ -567,7 +571,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, > if (interrupt_request & CPU_INTERRUPT_DEBUG) { > cpu_reset_interrupt(cpu, CPU_INTERRUPT_DEBUG); > cpu->exception_index = EXCP_DEBUG; > - qemu_mutex_unlock_iothread(); > + cpu_mutex_unlock(cpu); > return true; > } > if (replay_mode == REPLAY_MODE_PLAY && !replay_has_interrupt()) { > @@ -577,13 +581,15 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, > cpu_reset_interrupt(cpu, CPU_INTERRUPT_HALT); > cpu_halted_set(cpu, 1); > cpu->exception_index = EXCP_HLT; > - qemu_mutex_unlock_iothread(); > + cpu_mutex_unlock(cpu); > return true; > } > #if defined(TARGET_I386) > else if (interrupt_request & CPU_INTERRUPT_INIT) { > X86CPU *x86_cpu = X86_CPU(cpu); > CPUArchState *env = &x86_cpu->env; > + cpu_mutex_unlock(cpu); > + qemu_mutex_lock_iothread(); > replay_interrupt(); > cpu_svm_check_intercept_param(env, SVM_EXIT_INIT, 0, 0); > do_cpu_init(x86_cpu); > @@ -595,7 +601,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, > else if (interrupt_request & CPU_INTERRUPT_RESET) { > replay_interrupt(); > cpu_reset(cpu); > - qemu_mutex_unlock_iothread(); > + cpu_mutex_unlock(cpu); > return true; > } > #endif > @@ -604,7 +610,15 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, > True when it is, and we should restart on a new TB, > and via longjmp via cpu_loop_exit. */ > else { > + cpu_mutex_unlock(cpu); > + if (cc->bql_interrupt) { > + qemu_mutex_lock_iothread(); > + } > if (cc->cpu_exec_interrupt(cpu, interrupt_request)) { > + if (cc->bql_interrupt) { > + qemu_mutex_unlock_iothread(); > + } > + cpu_mutex_lock(cpu); > replay_interrupt(); > /* > * After processing the interrupt, ensure an EXCP_DEBUG is > @@ -614,6 +628,11 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, > cpu->exception_index = > (cpu->singlestep_enabled ? EXCP_DEBUG : -1); > *last_tb = NULL; > + } else { > + if (cc->bql_interrupt) { > + qemu_mutex_unlock_iothread(); > + } > + cpu_mutex_lock(cpu); > } > /* The target hook may have updated the 'cpu->interrupt_request'; > * reload the 'interrupt_request' value */ > @@ -627,7 +646,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu, > } > > /* If we exit via cpu_loop_exit/longjmp it is reset in cpu_exec */ > - qemu_mutex_unlock_iothread(); > + cpu_mutex_unlock(cpu); > } > > /* Finally, check if we need to exit to the main loop. */ > @@ -691,7 +710,6 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, > TranslationBlock *tb, > } > #endif > } > - > /* main execution loop */ > > int cpu_exec(CPUState *cpu) >