[Qemu-devel] [Qemu-Devel][PATCH 1/3] Adding an optional tb execution counter.

[vandersonmr <vandersonmr2@gmail.com>]

An uint64_t counter was added in the TranslationBlock struct and
it is incremented every time that the TB is executed.

Signed-off-by: vandersonmr <vandersonmr2@gmail.com>
---
 accel/tcg/tcg-runtime.c   | 6 ++++++
 accel/tcg/tcg-runtime.h   | 2 ++
 include/exec/exec-all.h   | 1 +
 include/exec/gen-icount.h | 7 +++++++
 linux-user/main.c         | 1 +
 vl.c                      | 1 +
 6 files changed, 18 insertions(+)

diff --git a/accel/tcg/tcg-runtime.c b/accel/tcg/tcg-runtime.c
index 8a1e408e31..d1f4127d31 100644
--- a/accel/tcg/tcg-runtime.c
+++ b/accel/tcg/tcg-runtime.c
@@ -167,3 +167,9 @@ void HELPER(exit_atomic)(CPUArchState *env)
 {
     cpu_loop_exit_atomic(env_cpu(env), GETPC());
 }
+
+void HELPER(inc_exec_freq)(void *ptr)
+{
+    TranslationBlock* tb = (TranslationBlock*) ptr;
+    atomic_inc(&tb->exec_freq);
+}
diff --git a/accel/tcg/tcg-runtime.h b/accel/tcg/tcg-runtime.h
index 4fa61b49b4..bf0b75dbe8 100644
--- a/accel/tcg/tcg-runtime.h
+++ b/accel/tcg/tcg-runtime.h
@@ -28,6 +28,8 @@ DEF_HELPER_FLAGS_1(lookup_tb_ptr, TCG_CALL_NO_WG_SE, ptr, env)
 
 DEF_HELPER_FLAGS_1(exit_atomic, TCG_CALL_NO_WG, noreturn, env)
 
+DEF_HELPER_FLAGS_1(inc_exec_freq, TCG_CALL_NO_RWG, void, ptr)
+
 #ifdef CONFIG_SOFTMMU
 
 DEF_HELPER_FLAGS_5(atomic_cmpxchgb, TCG_CALL_NO_WG,
diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
index 16034ee651..a80407622e 100644
--- a/include/exec/exec-all.h
+++ b/include/exec/exec-all.h
@@ -342,6 +342,7 @@ struct TranslationBlock {
     uint32_t flags; /* flags defining in which context the code was generated */
     uint16_t size;      /* size of target code for this block (1 <=
                            size <= TARGET_PAGE_SIZE) */
+    uint64_t exec_freq;
     uint16_t icount;
     uint32_t cflags;    /* compile flags */
 #define CF_COUNT_MASK  0x00007fff
diff --git a/include/exec/gen-icount.h b/include/exec/gen-icount.h
index f7669b6841..a540d12005 100644
--- a/include/exec/gen-icount.h
+++ b/include/exec/gen-icount.h
@@ -6,11 +6,18 @@
 /* Helpers for instruction counting code generation.  */
 
 static TCGOp *icount_start_insn;
+extern bool enable_freq_count;
 
 static inline void gen_tb_start(TranslationBlock *tb)
 {
     TCGv_i32 count, imm;
 
+    if (enable_freq_count) {
+        TCGv_ptr tb_ptr = tcg_temp_new_ptr();
+        tcg_gen_trunc_i64_ptr(tb_ptr, tcg_const_i64((int64_t) tb));
+        gen_helper_inc_exec_freq(tb_ptr);
+    }
+
     tcg_ctx->exitreq_label = gen_new_label();
     if (tb_cflags(tb) & CF_USE_ICOUNT) {
         count = tcg_temp_local_new_i32();
diff --git a/linux-user/main.c b/linux-user/main.c
index a59ae9439d..1bf7155670 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -58,6 +58,7 @@ static const char *seed_optarg;
 unsigned long mmap_min_addr;
 unsigned long guest_base;
 int have_guest_base;
+bool enable_freq_count = false;
 
 /*
  * When running 32-on-64 we should make sure we can fit all of the possible
diff --git a/vl.c b/vl.c
index 005468cbfb..cb6c0ad63d 100644
--- a/vl.c
+++ b/vl.c
@@ -190,6 +190,7 @@ bool boot_strict;
 uint8_t *boot_splash_filedata;
 int only_migratable; /* turn it off unless user states otherwise */
 bool wakeup_suspend_enabled;
+bool enable_freq_count = false;
 
 int icount_align_option;
 
-- 
2.22.0