Re: [Qemu-devel] [PATCH] target/mips: hold BQL for timer interrupts

[Philippe Mathieu-Daudé]

On Fri, Mar 3, 2017 at 8:20 AM, Yongbok Kim <address@hidden> wrote:
> Hold BQL when accessing timer which can cause interrupts
>
> Signed-off-by: Yongbok Kim <address@hidden>

Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

> ---
>  target/mips/op_helper.c | 21 ++++++++++++++++++---
>  1 file changed, 18 insertions(+), 3 deletions(-)
>
> diff --git a/target/mips/op_helper.c b/target/mips/op_helper.c
> index b683fcb..e5f3ea4 100644
> --- a/target/mips/op_helper.c
> +++ b/target/mips/op_helper.c
> @@ -17,6 +17,7 @@
>   * License along with this library; if not, see 
> <http://www.gnu.org/licenses/>.
>   */
>  #include "qemu/osdep.h"
> +#include "qemu/main-loop.h"
>  #include "cpu.h"
>  #include "qemu/host-utils.h"
>  #include "exec/helper-proto.h"
> @@ -827,7 +828,11 @@ target_ulong helper_mftc0_tcschefback(CPUMIPSState *env)
>
>  target_ulong helper_mfc0_count(CPUMIPSState *env)
>  {
> -    return (int32_t)cpu_mips_get_count(env);
> +    int32_t count;
> +    qemu_mutex_lock_iothread();
> +    count = (int32_t) cpu_mips_get_count(env);
> +    qemu_mutex_unlock_iothread();
> +    return count;
>  }
>
>  target_ulong helper_mftc0_entryhi(CPUMIPSState *env)
> @@ -1375,7 +1380,9 @@ void helper_mtc0_hwrena(CPUMIPSState *env, target_ulong 
> arg1)
>
>  void helper_mtc0_count(CPUMIPSState *env, target_ulong arg1)
>  {
> +    qemu_mutex_lock_iothread();
>      cpu_mips_store_count(env, arg1);
> +    qemu_mutex_unlock_iothread();
>  }
>
>  void helper_mtc0_entryhi(CPUMIPSState *env, target_ulong arg1)
> @@ -1424,7 +1431,9 @@ void helper_mttc0_entryhi(CPUMIPSState *env, 
> target_ulong arg1)
>
>  void helper_mtc0_compare(CPUMIPSState *env, target_ulong arg1)
>  {
> +    qemu_mutex_lock_iothread();
>      cpu_mips_store_compare(env, arg1);
> +    qemu_mutex_unlock_iothread();
>  }
>
>  void helper_mtc0_status(CPUMIPSState *env, target_ulong arg1)
> @@ -1475,7 +1484,9 @@ void helper_mtc0_srsctl(CPUMIPSState *env, target_ulong 
> arg1)
>
>  void helper_mtc0_cause(CPUMIPSState *env, target_ulong arg1)
>  {
> +    qemu_mutex_lock_iothread();
>      cpu_mips_store_cause(env, arg1);
> +    qemu_mutex_unlock_iothread();
>  }
>
>  void helper_mttc0_cause(CPUMIPSState *env, target_ulong arg1)
> @@ -2296,12 +2307,16 @@ target_ulong helper_rdhwr_synci_step(CPUMIPSState 
> *env)
>
>  target_ulong helper_rdhwr_cc(CPUMIPSState *env)
>  {
> +    int32_t count;
>      check_hwrena(env, 2, GETPC());
>  #ifdef CONFIG_USER_ONLY
> -    return env->CP0_Count;
> +    count = env->CP0_Count;
>  #else
> -    return (int32_t)cpu_mips_get_count(env);
> +    qemu_mutex_lock_iothread();
> +    count = (int32_t)cpu_mips_get_count(env);
> +    qemu_mutex_unlock_iothread();
>  #endif
> +    return count;
>  }
>
>  target_ulong helper_rdhwr_ccres(CPUMIPSState *env)
> --
> 2.7.4
>
>