linux-user: Call tcg_flush_jmp_cache() before re-using threads

[PATCH 2/3] accel/tcg: Factor out common tcg_exec_reset() helper

Posted by Philippe Mathieu-Daudé 3 months ago

Since tcg_cpu_reset_hold() is a system emulation specific
helper, factor tcg_exec_reset() out so we can use it from
user emulation, similarly to the [un]realize() handlers.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 accel/tcg/internal-common.h | 1 +
 accel/tcg/cpu-exec-common.c | 6 ++++++
 accel/tcg/tcg-accel-ops.c   | 4 ++--
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/accel/tcg/internal-common.h b/accel/tcg/internal-common.h
index c8d714256cb..8b474fc1256 100644
--- a/accel/tcg/internal-common.h
+++ b/accel/tcg/internal-common.h
@@ -55,6 +55,7 @@ void cpu_restore_state_from_tb(CPUState *cpu, TranslationBlock *tb,
 
 bool tcg_exec_realizefn(CPUState *cpu, Error **errp);
 void tcg_exec_unrealizefn(CPUState *cpu);
+void tcg_exec_reset(CPUState *cpu);
 
 /* current cflags for hashing/comparison */
 uint32_t curr_cflags(CPUState *cpu);
diff --git a/accel/tcg/cpu-exec-common.c b/accel/tcg/cpu-exec-common.c
index 6ecfc4e7c21..72ab9c3d977 100644
--- a/accel/tcg/cpu-exec-common.c
+++ b/accel/tcg/cpu-exec-common.c
@@ -21,6 +21,7 @@
 #include "system/cpus.h"
 #include "system/tcg.h"
 #include "qemu/plugin.h"
+#include "exec/tb-flush.h"
 #include "internal-common.h"
 
 bool tcg_allowed;
@@ -56,3 +57,8 @@ void cpu_loop_exit_atomic(CPUState *cpu, uintptr_t pc)
     cpu->exception_index = EXCP_ATOMIC;
     cpu_loop_exit_restore(cpu, pc);
 }
+
+void tcg_exec_reset(CPUState *cpu)
+{
+    tcg_flush_jmp_cache(cpu);
+}
diff --git a/accel/tcg/tcg-accel-ops.c b/accel/tcg/tcg-accel-ops.c
index 6e3f1fa92b2..4fe6821b017 100644
--- a/accel/tcg/tcg-accel-ops.c
+++ b/accel/tcg/tcg-accel-ops.c
@@ -34,7 +34,6 @@
 #include "qemu/timer.h"
 #include "exec/exec-all.h"
 #include "exec/hwaddr.h"
-#include "exec/tb-flush.h"
 #include "exec/translation-block.h"
 #include "gdbstub/enums.h"
 
@@ -44,6 +43,7 @@
 #include "tcg-accel-ops-mttcg.h"
 #include "tcg-accel-ops-rr.h"
 #include "tcg-accel-ops-icount.h"
+#include "internal-common.h"
 
 /* common functionality among all TCG variants */
 
@@ -83,7 +83,7 @@ int tcg_cpu_exec(CPUState *cpu)
 
 static void tcg_cpu_reset_hold(CPUState *cpu)
 {
-    tcg_flush_jmp_cache(cpu);
+    tcg_exec_reset(cpu);
 
     tlb_flush(cpu);
 }
-- 
2.47.1

Re: [PATCH 2/3] accel/tcg: Factor out common tcg_exec_reset() helper

Posted by Pierrick Bouvier 2 months, 2 weeks ago

On 1/2/25 10:25, Philippe Mathieu-Daudé wrote:
> Since tcg_cpu_reset_hold() is a system emulation specific
> helper, factor tcg_exec_reset() out so we can use it from
> user emulation, similarly to the [un]realize() handlers.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   accel/tcg/internal-common.h | 1 +
>   accel/tcg/cpu-exec-common.c | 6 ++++++
>   accel/tcg/tcg-accel-ops.c   | 4 ++--
>   3 files changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/accel/tcg/internal-common.h b/accel/tcg/internal-common.h
> index c8d714256cb..8b474fc1256 100644
> --- a/accel/tcg/internal-common.h
> +++ b/accel/tcg/internal-common.h
> @@ -55,6 +55,7 @@ void cpu_restore_state_from_tb(CPUState *cpu, TranslationBlock *tb,
>   
>   bool tcg_exec_realizefn(CPUState *cpu, Error **errp);
>   void tcg_exec_unrealizefn(CPUState *cpu);
> +void tcg_exec_reset(CPUState *cpu);
>   
>   /* current cflags for hashing/comparison */
>   uint32_t curr_cflags(CPUState *cpu);
> diff --git a/accel/tcg/cpu-exec-common.c b/accel/tcg/cpu-exec-common.c
> index 6ecfc4e7c21..72ab9c3d977 100644
> --- a/accel/tcg/cpu-exec-common.c
> +++ b/accel/tcg/cpu-exec-common.c
> @@ -21,6 +21,7 @@
>   #include "system/cpus.h"
>   #include "system/tcg.h"
>   #include "qemu/plugin.h"
> +#include "exec/tb-flush.h"
>   #include "internal-common.h"
>   
>   bool tcg_allowed;
> @@ -56,3 +57,8 @@ void cpu_loop_exit_atomic(CPUState *cpu, uintptr_t pc)
>       cpu->exception_index = EXCP_ATOMIC;
>       cpu_loop_exit_restore(cpu, pc);
>   }
> +
> +void tcg_exec_reset(CPUState *cpu)
> +{
> +    tcg_flush_jmp_cache(cpu);
> +}
> diff --git a/accel/tcg/tcg-accel-ops.c b/accel/tcg/tcg-accel-ops.c
> index 6e3f1fa92b2..4fe6821b017 100644
> --- a/accel/tcg/tcg-accel-ops.c
> +++ b/accel/tcg/tcg-accel-ops.c
> @@ -34,7 +34,6 @@
>   #include "qemu/timer.h"
>   #include "exec/exec-all.h"
>   #include "exec/hwaddr.h"
> -#include "exec/tb-flush.h"
>   #include "exec/translation-block.h"
>   #include "gdbstub/enums.h"
>   
> @@ -44,6 +43,7 @@
>   #include "tcg-accel-ops-mttcg.h"
>   #include "tcg-accel-ops-rr.h"
>   #include "tcg-accel-ops-icount.h"
> +#include "internal-common.h"
>   
>   /* common functionality among all TCG variants */
>   
> @@ -83,7 +83,7 @@ int tcg_cpu_exec(CPUState *cpu)
>   
>   static void tcg_cpu_reset_hold(CPUState *cpu)
>   {
> -    tcg_flush_jmp_cache(cpu);
> +    tcg_exec_reset(cpu);
>   
>       tlb_flush(cpu);
>   }

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>

Re: [PATCH 2/3] accel/tcg: Factor out common tcg_exec_reset() helper

Posted by Ilya Leoshkevich 2 months, 3 weeks ago

On Thu, 2025-01-02 at 19:25 +0100, Philippe Mathieu-Daudé wrote:
> Since tcg_cpu_reset_hold() is a system emulation specific
> helper, factor tcg_exec_reset() out so we can use it from
> user emulation, similarly to the [un]realize() handlers.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>  accel/tcg/internal-common.h | 1 +
>  accel/tcg/cpu-exec-common.c | 6 ++++++
>  accel/tcg/tcg-accel-ops.c   | 4 ++--
>  3 files changed, 9 insertions(+), 2 deletions(-)

Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>