vandersonmr <vanderson...@gmail.com> writes:
> If a TB has a TBS (TBStatistics) with the TB_EXEC_STATS
> enabled, then we instrument the start code of the TB
> to atomically count the number of times it is executed.
> The execution count of the TB is stored in its respective
> TBS.
>
> Signed-off-by: Vanderson M. do Rosario <vanderson...@gmail.com>
> ---
> accel/tcg/tcg-runtime.c | 7 +++++++
> accel/tcg/tcg-runtime.h | 2 ++
> accel/tcg/translate-all.c | 8 ++++++++
> accel/tcg/translator.c | 1 +
> include/exec/gen-icount.h | 9 +++++++++
> include/exec/tb-stats.h | 11 +++++++++++
> include/qemu/log.h | 6 ++++++
> util/log.c | 11 +++++++++++
> 8 files changed, 55 insertions(+)
>
> diff --git a/accel/tcg/tcg-runtime.c b/accel/tcg/tcg-runtime.c
> index 8a1e408e31..f332eae334 100644
> --- a/accel/tcg/tcg-runtime.c
> +++ b/accel/tcg/tcg-runtime.c
> @@ -167,3 +167,10 @@ void HELPER(exit_atomic)(CPUArchState *env)
> {
> cpu_loop_exit_atomic(env_cpu(env), GETPC());
> }
> +
> +void HELPER(inc_exec_freq)(void *ptr)
> +{
> + TBStatistics *stats = (TBStatistics *) ptr;
> + g_assert(stats);
> + atomic_inc(&stats->executions.total);
> +}
> 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/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
> index a574890a80..7497dae508 100644
> --- a/accel/tcg/translate-all.c
> +++ b/accel/tcg/translate-all.c
> @@ -1785,6 +1785,14 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
> */
> if (tb_stats_collection_enabled()) {
> tb->tb_stats = tb_get_stats(phys_pc, pc, cs_base, flags);
> + uint32_t flag = get_default_tbstats_flag();
> +
> + if (qemu_log_in_addr_range(tb->pc)) {
> + if (flag & TB_EXEC_STATS) {
> + tb->tb_stats->stats_enabled |= TB_EXEC_STATS;
> + }
> + }
> +
> } else {
> tb->tb_stats = NULL;
> }
> diff --git a/accel/tcg/translator.c b/accel/tcg/translator.c
> index 9226a348a3..396a11e828 100644
> --- a/accel/tcg/translator.c
> +++ b/accel/tcg/translator.c
> @@ -46,6 +46,7 @@ void translator_loop(const TranslatorOps *ops,
> DisasContextBase *db,
>
> ops->init_disas_context(db, cpu);
> tcg_debug_assert(db->is_jmp == DISAS_NEXT); /* no early exit */
> + gen_tb_exec_count(tb);
>
> /* Reset the temp count so that we can identify leaks */
> tcg_clear_temp_count();
> diff --git a/include/exec/gen-icount.h b/include/exec/gen-icount.h
> index f7669b6841..b3efe41894 100644
> --- a/include/exec/gen-icount.h
> +++ b/include/exec/gen-icount.h
> @@ -7,6 +7,15 @@
>
> static TCGOp *icount_start_insn;
>
> +static inline void gen_tb_exec_count(TranslationBlock *tb)
> +{
> + if (tb_stats_enabled(tb, TB_EXEC_STATS)) {
> + TCGv_ptr ptr = tcg_const_ptr(tb->tb_stats);
> + gen_helper_inc_exec_freq(ptr);
> + tcg_temp_free_ptr(ptr);
> + }
> +}
> +
> static inline void gen_tb_start(TranslationBlock *tb)
> {
> TCGv_i32 count, imm;
> diff --git a/include/exec/tb-stats.h b/include/exec/tb-stats.h
> index 0913155ec3..ee1e8de0d3 100644
> --- a/include/exec/tb-stats.h
> +++ b/include/exec/tb-stats.h
> @@ -6,6 +6,9 @@
> #include "exec/tb-context.h"
> #include "tcg.h"
>
> +#define tb_stats_enabled(tb, JIT_STATS) \
> + (tb && tb->tb_stats && (tb->tb_stats->stats_enabled & JIT_STATS))
> +
> typedef struct TBStatistics TBStatistics;
>
> /*
> @@ -22,6 +25,14 @@ struct TBStatistics {
> uint32_t flags;
> /* cs_base isn't included in the hash but we do check for matches */
> target_ulong cs_base;
> +
> + uint32_t stats_enabled;
> +
> + /* Execution stats */
> + struct {
> + unsigned long total;
> + unsigned long atomic;
We are not incrementing atomic in this patch. Also it's not total so
maybe "normal" makes more sense. Something like:
fixup! accel: collecting TB execution count
4 files changed, 11 insertions(+), 6 deletions(-)
accel/tcg/cpu-exec.c | 4 ++++
accel/tcg/tb-stats.c | 9 +++++----
accel/tcg/tcg-runtime.c | 2 +-
include/exec/tb-stats.h | 2 +-
modified accel/tcg/cpu-exec.c
@@ -252,6 +252,10 @@ void cpu_exec_step_atomic(CPUState *cpu)
start_exclusive();
+ if (tb_stats_enabled(tb, TB_EXEC_STATS)) {
+ tb->tb_stats->executions.atomic++;
+ }
+
/* Since we got here, we know that parallel_cpus must be true. */
parallel_cpus = false;
in_exclusive_region = true;
modified accel/tcg/tb-stats.c
@@ -233,11 +233,12 @@ static void dump_tb_header(TBStatistics *tbs)
float guest_host_prop = g ? ((float) h / g) : 0;
qemu_log("TB%d: phys:0x"TB_PAGE_ADDR_FMT" virt:0x"TARGET_FMT_lx
- " flags:%#08x (trans:%lu uncached:%lu exec:%lu ints: g:%u op:%u
op_opt:%u h:%u h/g:%.2f spills:%d)\n",
+ " flags:%#08x (trans:%lu uncached:%lu exec:%lu/%lu ints: g:%u
op:%u op_opt:%u h:%u h/g:%.2f spills:%d)\n",
tbs->display_id,
tbs->phys_pc, tbs->pc, tbs->flags,
tbs->translations.total, tbs->translations.uncached,
- tbs->executions.total, g, ops, ops_opt, h, guest_host_prop,
+ tbs->executions.normal, tbs->executions.atomic,
+ g, ops, ops_opt, h, guest_host_prop,
spills);
}
@@ -254,8 +255,8 @@ inverse_sort_tbs(gconstpointer p1, gconstpointer p2,
gpointer psort_by)
c1 = tbs1->code.spills;
c2 = tbs2->code.spills;
} else if (likely(sort_by == SORT_BY_HOTNESS)) {
- c1 = tbs1->executions.total;
- c2 = tbs2->executions.total;
+ c1 = tbs1->executions.normal;
+ c2 = tbs2->executions.normal;
} else if (likely(sort_by == SORT_BY_HG)) {
if (tbs1->code.num_guest_inst == 0) {
return -1;
modified accel/tcg/tcg-runtime.c
@@ -172,5 +172,5 @@ void HELPER(inc_exec_freq)(void *ptr)
{
TBStatistics *stats = (TBStatistics *) ptr;
g_assert(stats);
- atomic_inc(&stats->executions.total);
+ atomic_inc(&stats->executions.normal);
}
modified include/exec/tb-stats.h
@@ -33,7 +33,7 @@ struct TBStatistics {
/* Execution stats */
struct {
- unsigned long total;
+ unsigned long normal;
unsigned long atomic;
} executions;
> diff --git a/include/qemu/log.h b/include/qemu/log.h
> index e175d4d5d0..b213411836 100644
> --- a/include/qemu/log.h
> +++ b/include/qemu/log.h
> @@ -129,10 +129,16 @@ void qemu_log_flush(void);
> /* Close the log file */
> void qemu_log_close(void);
>
> +#define TB_NOTHING 0
> +#define TB_EXEC_STATS (1 << 1)
> +
> void enable_collect_tb_stats(void);
> void disable_collect_tb_stats(void);
> void pause_collect_tb_stats(void);
> bool tb_stats_collection_enabled(void);
> bool tb_stats_collection_paused(void);
>
> +void set_default_tbstats_flag(uint32_t flag);
> +uint32_t get_default_tbstats_flag(void);
> +
> #endif
> diff --git a/util/log.c b/util/log.c
> index ab73fdc100..f81653d712 100644
> --- a/util/log.c
> +++ b/util/log.c
> @@ -354,3 +354,14 @@ bool tb_stats_collection_paused(void)
> return tcg_collect_tb_stats == 2;
> }
>
> +uint32_t default_tbstats_flag;
> +
> +void set_default_tbstats_flag(uint32_t flag)
> +{
> + default_tbstats_flag = flag;
> +}
> +
> +uint32_t get_default_tbstats_flag(void)
> +{
> + return default_tbstats_flag;
> +}
Some comment about not overloading log.c as before.
--
Alex Bennée
