[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requestin
From: |
Pavel Dovgaluk |
Subject: |
Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting |
Date: |
Fri, 5 Dec 2014 15:59:01 +0300 |
> From: Paolo Bonzini [mailto:address@hidden
> On 05/12/2014 11:55, Pavel Dovgaluk wrote:
> >> >
> >> > And why is can_do_io zero? :) Is the fix to move the place where
> >> > can_do_io becomes nonzero?
> > can_do_io is set by gen_io_start function.
> > As I understand, it is used to protect determinism in icount mode,
> > because it allows non-deterministic (port io, raising interrupt)
> > operations only at the end of the translation blocks.
> > When someone tries to use MMIO in the middle of TB, that TB is
> > recompiled to place this instruction at the end of the block.
> >
> > Do you mean that we can set can_do_io before execution of the block
> > and reset it at the beginning of the execution?
>
> Yes, we could try setting it after execution of the block and clearing
> it afterwards. Peter knows that part of icount better though (I know
> mostly the timer/warping parts).
Ok, how about these changes?
diff --git a/cpu-exec.c b/cpu-exec.c
index f52f292..88675ca 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -168,7 +168,9 @@ static inline tcg_target_ulong cpu_tb_exec(CPUState *cpu,
uint8_t *tb_ptr)
}
#endif /* DEBUG_DISAS */
+ cpu->can_do_io = 0;
next_tb = tcg_qemu_tb_exec(env, tb_ptr);
+ cpu->can_do_io = 1;
trace_exec_tb_exit((void *) (next_tb & ~TB_EXIT_MASK),
next_tb & TB_EXIT_MASK);
@@ -548,6 +550,7 @@ int cpu_exec(CPUArchState *env)
cpu = current_cpu;
env = cpu->env_ptr;
cc = CPU_GET_CLASS(cpu);
+ cpu->can_do_io = 1;
#ifdef TARGET_I386
x86_cpu = X86_CPU(cpu);
#endif
diff --git a/cpus.c b/cpus.c
index 0c33458..7a45a51 100644
--- a/cpus.c
+++ b/cpus.c
@@ -934,6 +934,7 @@ static void *qemu_kvm_cpu_thread_fn(void *arg)
qemu_mutex_lock(&qemu_global_mutex);
qemu_thread_get_self(cpu->thread);
cpu->thread_id = qemu_get_thread_id();
+ cpu->can_do_io = 1;
current_cpu = cpu;
r = kvm_init_vcpu(cpu);
@@ -974,6 +975,7 @@ static void *qemu_dummy_cpu_thread_fn(void *arg)
qemu_mutex_lock_iothread();
qemu_thread_get_self(cpu->thread);
cpu->thread_id = qemu_get_thread_id();
+ cpu->can_do_io = 1;
sigemptyset(&waitset);
sigaddset(&waitset, SIG_IPI);
@@ -1016,6 +1018,7 @@ static void *qemu_tcg_cpu_thread_fn(void *arg)
CPU_FOREACH(cpu) {
cpu->thread_id = qemu_get_thread_id();
cpu->created = true;
+ cpu->can_do_io = 1;
}
qemu_cond_signal(&qemu_cpu_cond);
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting, Paolo Bonzini, 2014/12/03
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting, Pavel Dovgaluk, 2014/12/04
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting, Paolo Bonzini, 2014/12/04
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting, Pavel Dovgaluk, 2014/12/05
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting, Paolo Bonzini, 2014/12/05
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting, Pavel Dovgaluk, 2014/12/05
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting, Paolo Bonzini, 2014/12/05
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting,
Pavel Dovgaluk <=
- Message not available
- Re: [Qemu-devel] [RFC PATCH v5 07/31] icount: implement icount requesting, Paolo Bonzini, 2014/12/05