target/riscv: Add itrigger_enabled field to CPURISCVState

Avoid calling riscv_itrigger_enabled() when calculate the tbflags.
As the itrigger enable status can only be changed when write
tdata1, migration load or itrigger fire, update env->itrigger_enabled
at these places.

Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20221013062946.7530-5-zhiwei_liu@linux.alibaba.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/cpu.h

@@ -331,6 +331,7 @@ struct CPUArchState {
     struct CPUWatchpoint *cpu_watchpoint[RV_MAX_TRIGGERS];
     QEMUTimer *itrigger_timer[RV_MAX_TRIGGERS];
     int64_t last_icount;
+    bool itrigger_enabled;
 
     /* machine specific rdtime callback */
     uint64_t (*rdtime_fn)(void *);

target/riscv/cpu_helper.c

@@ -106,8 +106,7 @@ void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
                            get_field(env->mstatus_hs, MSTATUS_VS));
     }
     if (riscv_feature(env, RISCV_FEATURE_DEBUG) && !icount_enabled()) {
-        flags = FIELD_DP32(flags, TB_FLAGS, ITRIGGER,
-                           riscv_itrigger_enabled(env));
+        flags = FIELD_DP32(flags, TB_FLAGS, ITRIGGER, env->itrigger_enabled);
     }
 #endif
 

target/riscv/debug.c

@@ -563,6 +563,7 @@ void helper_itrigger_match(CPURISCVState *env)
         }
         itrigger_set_count(env, i, count--);
         if (!count) {
+            env->itrigger_enabled = riscv_itrigger_enabled(env);
             do_trigger_action(env, i);
         }
     }
@@ -660,6 +661,8 @@ static void itrigger_reg_write(CPURISCVState *env, target_ulong index,
                 /* set the count to timer */
                 timer_mod(env->itrigger_timer[index],
                           env->last_icount + itrigger_get_count(env, index));
+            } else {
+                env->itrigger_enabled = riscv_itrigger_enabled(env);
             }
         }
         break;

target/riscv/machine.c

@@ -21,6 +21,8 @@
 #include "qemu/error-report.h"
 #include "sysemu/kvm.h"
 #include "migration/cpu.h"
+#include "sysemu/cpu-timers.h"
+#include "debug.h"
 
 static bool pmp_needed(void *opaque)
 {
@@ -229,11 +231,24 @@ static bool debug_needed(void *opaque)
     return riscv_feature(env, RISCV_FEATURE_DEBUG);
 }
 
+static int debug_post_load(void *opaque, int version_id)
+{
+    RISCVCPU *cpu = opaque;
+    CPURISCVState *env = &cpu->env;
+
+    if (icount_enabled()) {
+        env->itrigger_enabled = riscv_itrigger_enabled(env);
+    }
+
+    return 0;
+}
+
 static const VMStateDescription vmstate_debug = {
     .name = "cpu/debug",
     .version_id = 2,
     .minimum_version_id = 2,
     .needed = debug_needed,
+    .post_load = debug_post_load,
     .fields = (VMStateField[]) {
         VMSTATE_UINTTL(env.trigger_cur, RISCVCPU),
         VMSTATE_UINTTL_ARRAY(env.tdata1, RISCVCPU, RV_MAX_TRIGGERS),