[RFC PATCH 04/24] accel/tcg: Rename user-mode do_interrupt hack as fake_user_exception

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

do_interrupt() is sysemu specific. However due to some X86
specific hack, it is also used in user-mode emulation, which
is why it couldn't be restricted to CONFIG_SOFTMMU (see the
comment around added in commit 78271684719: "cpu: tcg_ops:
move to tcg-cpu-ops.h, keep a pointer in CPUClass").
Keep the hack but rename the handler as fake_user_exception()
and restrict do_interrupt() to sysemu.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
RFC: Any better name / idea here?
---
 include/hw/core/tcg-cpu-ops.h | 22 ++++++++++++++--------
 accel/tcg/cpu-exec.c          |  4 ++--
 target/i386/tcg/tcg-cpu.c     |  6 ++++--
 3 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/include/hw/core/tcg-cpu-ops.h b/include/hw/core/tcg-cpu-ops.h
index eab27d0c030..600f0349659 100644
--- a/include/hw/core/tcg-cpu-ops.h
+++ b/include/hw/core/tcg-cpu-ops.h
@@ -37,14 +37,6 @@ struct TCGCPUOps {
     void (*cpu_exec_exit)(CPUState *cpu);
     /** @cpu_exec_interrupt: Callback for processing interrupts in cpu_exec */
     bool (*cpu_exec_interrupt)(CPUState *cpu, int interrupt_request);
-    /**
-     * @do_interrupt: Callback for interrupt handling.
-     *
-     * note that this is in general SOFTMMU only, but it actually isn't
-     * because of an x86 hack (accel/tcg/cpu-exec.c), so we cannot put it
-     * in the SOFTMMU section in general.
-     */
-    void (*do_interrupt)(CPUState *cpu);
     /**
      * @tlb_fill: Handle a softmmu tlb miss or user-only address fault
      *
@@ -61,6 +53,20 @@ struct TCGCPUOps {
     void (*debug_excp_handler)(CPUState *cpu);
 
 #ifdef NEED_CPU_H
+#if defined(CONFIG_USER_ONLY) && defined(TARGET_I386)
+    /**
+     * @fake_user_exception: Callback for 'fake exception' handling.
+     *
+     * Simulate 'fake exception' which will be handled outside the
+     * cpu execution loop (hack for x86 user mode).
+     */
+    void (*fake_user_exception)(CPUState *cpu);
+#else
+    /**
+     * @do_interrupt: Callback for interrupt handling.
+     */
+    void (*do_interrupt)(CPUState *cpu);
+#endif /* !CONFIG_USER_ONLY || !TARGET_I386 */
 #ifdef CONFIG_SOFTMMU
     /**
      * @do_transaction_failed: Callback for handling failed memory transactions
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index e5c0ccd1a2a..3e387c944c5 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -651,8 +651,8 @@ static inline bool cpu_handle_exception(CPUState *cpu, int *ret)
            loop */
 #if defined(TARGET_I386)
         CPUClass *cc = CPU_GET_CLASS(cpu);
-        cc->tcg_ops->do_interrupt(cpu);
-#endif
+        cc->tcg_ops->fake_user_exception(cpu);
+#endif /* TARGET_I386 */
         *ret = cpu->exception_index;
         cpu->exception_index = -1;
         return true;
diff --git a/target/i386/tcg/tcg-cpu.c b/target/i386/tcg/tcg-cpu.c
index 93a79a57415..dce800a8953 100644
--- a/target/i386/tcg/tcg-cpu.c
+++ b/target/i386/tcg/tcg-cpu.c
@@ -73,9 +73,11 @@ static const struct TCGCPUOps x86_tcg_ops = {
     .cpu_exec_enter = x86_cpu_exec_enter,
     .cpu_exec_exit = x86_cpu_exec_exit,
     .cpu_exec_interrupt = x86_cpu_exec_interrupt,
-    .do_interrupt = x86_cpu_do_interrupt,
     .tlb_fill = x86_cpu_tlb_fill,
-#ifndef CONFIG_USER_ONLY
+#ifdef CONFIG_USER_ONLY
+    .fake_user_exception = x86_cpu_do_interrupt,
+#else
+    .do_interrupt = x86_cpu_do_interrupt,
     .debug_excp_handler = breakpoint_handler,
     .debug_check_breakpoint = x86_debug_check_breakpoint,
 #endif /* !CONFIG_USER_ONLY */
-- 
2.31.1