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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 On 8/13/26 20:16, Philippe Mathieu-Daudé wrote: > Reduce lock contention by acquiring / releasing the BQL > outside of the entire vCPU inner loop. > > Signed-off-by: Philippe Mathieu-Daudé > --- > target/arm/hvf/hvf.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c > index c14ea54a67f..9c6408d2e25 100644 > --- a/target/arm/hvf/hvf.c > +++ b/target/arm/hvf/hvf.c > @@ -2598,20 +2598,20 @@ int hvf_arch_vcpu_exec(CPUState *cpu) > } > } > > + bql_unlock(); > + cpu_exec_start(cpu); > + > /* Inner vCPU loop */ > do { > if (!(cpu->singlestep_flags & SSTEP_NOIRQ) && > hvf_inject_interrupts(cpu)) { It always return zero, so you can make it void and change to if (!(cpu->singlestep_flags & SSTEP_NOIRQ)) { hvf_inject_interrupts(cpu); } However, a bigger question: who calls cpu_reset_interrupt() here: if (cpu_test_interrupt(cpu, CPU_INTERRUPT_FIQ)) { trace_hvf_inject_fiq(); hv_vcpu_set_pending_interrupt(cpu->accel->fd, HV_INTERRUPT_TYPE_FIQ, true); } if (cpu_test_interrupt(cpu, CPU_INTERRUPT_HARD)) { trace_hvf_inject_irq(); hv_vcpu_set_pending_interrupt(cpu->accel->fd, HV_INTERRUPT_TYPE_IRQ, true); } and can this be changed to do something like arm_cpu_kvm_set_irq() instead? Having the function called only with level == true is a bit unsettling... Paolo > - return EXCP_INTERRUPT; > + ret = EXCP_INTERRUPT; > + break; > } > > flush_cpu_state(cpu); > > - bql_unlock(); > - cpu_exec_start(cpu); > r = hv_vcpu_run(cpu->accel->fd); > - cpu_exec_end(cpu); > - bql_lock(); > switch (r) { > case HV_SUCCESS: > ret = hvf_handle_vmexit(cpu, cpu->accel->exit); > @@ -2624,6 +2624,9 @@ int hvf_arch_vcpu_exec(CPUState *cpu) > } > } while (ret == 0); > > + cpu_exec_end(cpu); > + bql_lock(); > + > return ret; > } >