Message ID | 20190720010235.32444-7-vandersonmr2@gmail.com |
---|---|
State | New |
Headers | show |
Series | Measure Tiny Code Generation Quality | expand |
vandersonmr <vandersonmr2@gmail.com> writes: > Adding tb_stats [start|pause|stop|filter] command to hmp. > This allows controlling the collection of statistics. > It is also possible to set the level of collection: > all, jit, or exec. > > The goal of this command is to allow the dynamic exploration > of the TCG behavior and quality. Therefore, for now, a > corresponding QMP command is not worthwhile. > > Signed-off-by: Vanderson M. do Rosario <vandersonmr2@gmail.com> > --- > accel/tcg/tb-stats.c | 107 ++++++++++++++++++++++++++++++++++++++++ > hmp-commands.hx | 17 +++++++ > include/exec/tb-stats.h | 13 +++++ > include/qemu/log.h | 1 + > monitor/misc.c | 40 +++++++++++++++ > 5 files changed, 178 insertions(+) > > diff --git a/accel/tcg/tb-stats.c b/accel/tcg/tb-stats.c > index 44497d4f9b..6c330e1b02 100644 > --- a/accel/tcg/tb-stats.c > +++ b/accel/tcg/tb-stats.c > @@ -6,6 +6,9 @@ > > #include "qemu/qemu-print.h" > > +/* only accessed in safe work */ > +static GList *last_search; > + > struct jit_profile_info { > uint64_t translations; > uint64_t aborted; > @@ -104,4 +107,108 @@ void dump_jit_profile_info(TCGProfile *s) > } > } > > +static void dessaloc_tbstats(void *p, uint32_t hash, void *userp) > +{ > + g_free(p); > +} surely free_tbstats would be a better name? > + > +void clean_tbstats(void) > +{ > + /* remove all tb_stats */ > + qht_iter(&tb_ctx.tb_stats, dessaloc_tbstats, NULL); > + qht_destroy(&tb_ctx.tb_stats); > +} > + > +static void reset_tbstats_flag(void *p, uint32_t hash, void *userp) > +{ > + uint32_t flag = *((int *)userp); > + TBStatistics *tbs = p; > + tbs->stats_enabled = flag; > +} > + > +void set_tbstats_flags(uint32_t flag) > +{ > + /* iterate over tbstats setting their flag as TB_NOTHING */ > + qht_iter(&tb_ctx.tb_stats, reset_tbstats_flag, &flag); > +} > + > +void do_hmp_tbstats_safe(CPUState *cpu, run_on_cpu_data icmd) > +{ > + struct TbstatsCommand *cmdinfo = icmd.host_ptr; > + int cmd = cmdinfo->cmd; > + uint32_t level = cmdinfo->level; > + > + /* for safe, always pause TB generation while running this commands */ > + mmap_lock(); This doesn't serialise in all cases - in fact it's running as safe work which is our serial case. The mmap_lock is really only needed for code generation in linux-user. I think the lock/unlock can be dropped from these operations. > + > + switch (cmd) { > + case START: > + if (tb_stats_collection_paused()) { > + set_tbstats_flags(level); > + } else { > + if (tb_stats_collection_enabled()) { > + qemu_printf("TB information already being recorded"); > + return; > + } > + qht_init(&tb_ctx.tb_stats, tb_stats_cmp, CODE_GEN_HTABLE_SIZE, > + QHT_MODE_AUTO_RESIZE); I'm wary of initialising this in multiple places. Maybe move this to enable_collect_tb_stats and drop the initialisation in tb_htable_init. > + } > + > + set_default_tbstats_flag(level); > + enable_collect_tb_stats(); > + tb_flush(cpu); > + break; > + case PAUSE: > + if (!tb_stats_collection_enabled()) { > + qemu_printf("TB information not being recorded"); > + return; > + } > + > + /* Continue to create TBStatistic structures but stop collecting statistics */ > + pause_collect_tb_stats(); > + tb_flush(cpu); > + set_default_tbstats_flag(TB_NOTHING); > + set_tbstats_flags(TB_PAUSED); Minor style suggestion - make the tb_flush the last thing you do once you have moved things around. You are in safe work so nothing should be happening anyway and it reads better. > + break; > + case STOP: > + if (!tb_stats_collection_enabled()) { > + qemu_printf("TB information not being recorded"); > + return; > + } > + > + /* Dissalloc all TBStatistics structures and stop creating new ones */ > + disable_collect_tb_stats(); > + tb_flush(cpu); > + clean_tbstats(); As above. > + break; > + case FILTER: > + if (!tb_stats_collection_enabled()) { > + qemu_printf("TB information not being recorded"); > + return; > + } > + if (!last_search) { > + qemu_printf("no search on record! execute info tbs before filtering!"); > + return; > + } > + > + tb_flush(cpu); > + set_default_tbstats_flag(TB_NOTHING); > + > + /* Set all tbstats as paused, then return only the ones from last_search */ > + pause_collect_tb_stats(); > + set_tbstats_flags(TB_PAUSED); > + > + for (GList *iter = last_search; iter; iter = g_list_next(iter)) { > + TBStatistics *tbs = iter->data; > + tbs->stats_enabled = level; > + } If we are only interested in tracking the N hotestest at this point we want to prevent allocation of new TBStats and free all the unused ones? > + > + break; > + default: /* INVALID */ g_assert_not_reached()? This would be an internal bug if we ever sent the wrong command? > + break; > + } > + > + mmap_unlock(); > + g_free(cmdinfo); > +} > > diff --git a/hmp-commands.hx b/hmp-commands.hx > index bfa5681dd2..419898751e 100644 > --- a/hmp-commands.hx > +++ b/hmp-commands.hx > @@ -1885,6 +1885,23 @@ STEXI > @findex qemu-io > Executes a qemu-io command on the given block device. > > +ETEXI > +#if defined(CONFIG_TCG) > + { > + .name = "tb_stats", > + .args_type = "command:s,level:s?", > + .params = "command [stats_level]", > + .help = "Control tb statistics collection:" > + "tb_stats (start|pause|stop|filter) > [all|jit_stats|exec_stats]", What does filter do? > + .cmd = hmp_tbstats, > + }, > +#endif > + > +STEXI > +@item tb_stats > +@findex > +Control recording tb statistics > + > ETEXI > > { > diff --git a/include/exec/tb-stats.h b/include/exec/tb-stats.h > index 7d775f2c0d..d1debd3262 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" > > +enum SortBy { SORT_BY_HOTNESS, SORT_BY_HG /* Host/Guest */, SORT_BY_SPILLS }; > +enum TbstatsCmd { START, PAUSE, STOP, FILTER }; > + > #define tb_stats_enabled(tb, JIT_STATS) \ > (tb && tb->tb_stats && (tb->tb_stats->stats_enabled & JIT_STATS)) > > @@ -60,4 +63,14 @@ bool tb_stats_cmp(const void *ap, const void *bp); > > void dump_jit_profile_info(TCGProfile *s); > > +void set_tbstats_flags(uint32_t flags); > +void clean_tbstats(void); > + > +struct TbstatsCommand { > + enum TbstatsCmd cmd; > + uint32_t level; > +}; > + > +void do_hmp_tbstats_safe(CPUState *cpu, run_on_cpu_data icmd); > + > #endif > diff --git a/include/qemu/log.h b/include/qemu/log.h > index 93642603e5..47071d72c7 100644 > --- a/include/qemu/log.h > +++ b/include/qemu/log.h > @@ -133,6 +133,7 @@ void qemu_log_close(void); > #define TB_NOTHING 0 > #define TB_EXEC_STATS (1 << 1) > #define TB_JIT_STATS (1 << 2) > +#define TB_PAUSED (1 << 3) > > void enable_collect_tb_stats(void); > void disable_collect_tb_stats(void); > diff --git a/monitor/misc.c b/monitor/misc.c > index 00338c002a..aea9b0db4f 100644 > --- a/monitor/misc.c > +++ b/monitor/misc.c > @@ -459,6 +459,46 @@ static void hmp_info_registers(Monitor *mon, const QDict *qdict) > } > > #ifdef CONFIG_TCG > +static void hmp_tbstats(Monitor *mon, const QDict *qdict) > +{ > + if (!tcg_enabled()) { > + error_report("TB information is only available with accel=tcg"); > + return; > + } > + > + char *cmd = (char *) qdict_get_try_str(qdict, "command"); > + enum TbstatsCmd icmd = -1; > + > + if (strcmp(cmd, "start") == 0) { > + icmd = START; > + } else if (strcmp(cmd, "pause") == 0) { > + icmd = PAUSE; > + } else if (strcmp(cmd, "stop") == 0) { > + icmd = STOP; > + } else if (strcmp(cmd, "filter") == 0) { > + icmd = FILTER; > + } else { > + error_report("invalid command!"); > + } > + > + char *slevel = (char *) qdict_get_try_str(qdict, "level"); > + uint32_t level = TB_EXEC_STATS | TB_JIT_STATS; > + if (slevel) { > + if (strcmp(slevel, "jit_stats") == 0) { > + level = TB_JIT_STATS; > + } else if (strcmp(slevel, "exec_stats") == 0) { > + level = TB_EXEC_STATS; > + } > + } > + > + struct TbstatsCommand *tbscommand = g_new0(struct TbstatsCommand, 1); > + tbscommand->cmd = icmd; > + tbscommand->level = level; It might be worth considering squashing these into a single pointer to avoid the allocation and free? > + async_safe_run_on_cpu(first_cpu, do_hmp_tbstats_safe, > + RUN_ON_CPU_HOST_PTR(tbscommand)); > + > +} > + > static void hmp_info_jit(Monitor *mon, const QDict *qdict) > { > if (!tcg_enabled()) { -- Alex Bennée
diff --git a/accel/tcg/tb-stats.c b/accel/tcg/tb-stats.c index 44497d4f9b..6c330e1b02 100644 --- a/accel/tcg/tb-stats.c +++ b/accel/tcg/tb-stats.c @@ -6,6 +6,9 @@ #include "qemu/qemu-print.h" +/* only accessed in safe work */ +static GList *last_search; + struct jit_profile_info { uint64_t translations; uint64_t aborted; @@ -104,4 +107,108 @@ void dump_jit_profile_info(TCGProfile *s) } } +static void dessaloc_tbstats(void *p, uint32_t hash, void *userp) +{ + g_free(p); +} + +void clean_tbstats(void) +{ + /* remove all tb_stats */ + qht_iter(&tb_ctx.tb_stats, dessaloc_tbstats, NULL); + qht_destroy(&tb_ctx.tb_stats); +} + +static void reset_tbstats_flag(void *p, uint32_t hash, void *userp) +{ + uint32_t flag = *((int *)userp); + TBStatistics *tbs = p; + tbs->stats_enabled = flag; +} + +void set_tbstats_flags(uint32_t flag) +{ + /* iterate over tbstats setting their flag as TB_NOTHING */ + qht_iter(&tb_ctx.tb_stats, reset_tbstats_flag, &flag); +} + +void do_hmp_tbstats_safe(CPUState *cpu, run_on_cpu_data icmd) +{ + struct TbstatsCommand *cmdinfo = icmd.host_ptr; + int cmd = cmdinfo->cmd; + uint32_t level = cmdinfo->level; + + /* for safe, always pause TB generation while running this commands */ + mmap_lock(); + + switch (cmd) { + case START: + if (tb_stats_collection_paused()) { + set_tbstats_flags(level); + } else { + if (tb_stats_collection_enabled()) { + qemu_printf("TB information already being recorded"); + return; + } + qht_init(&tb_ctx.tb_stats, tb_stats_cmp, CODE_GEN_HTABLE_SIZE, + QHT_MODE_AUTO_RESIZE); + } + + set_default_tbstats_flag(level); + enable_collect_tb_stats(); + tb_flush(cpu); + break; + case PAUSE: + if (!tb_stats_collection_enabled()) { + qemu_printf("TB information not being recorded"); + return; + } + + /* Continue to create TBStatistic structures but stop collecting statistics */ + pause_collect_tb_stats(); + tb_flush(cpu); + set_default_tbstats_flag(TB_NOTHING); + set_tbstats_flags(TB_PAUSED); + break; + case STOP: + if (!tb_stats_collection_enabled()) { + qemu_printf("TB information not being recorded"); + return; + } + + /* Dissalloc all TBStatistics structures and stop creating new ones */ + disable_collect_tb_stats(); + tb_flush(cpu); + clean_tbstats(); + break; + case FILTER: + if (!tb_stats_collection_enabled()) { + qemu_printf("TB information not being recorded"); + return; + } + if (!last_search) { + qemu_printf("no search on record! execute info tbs before filtering!"); + return; + } + + tb_flush(cpu); + set_default_tbstats_flag(TB_NOTHING); + + /* Set all tbstats as paused, then return only the ones from last_search */ + pause_collect_tb_stats(); + set_tbstats_flags(TB_PAUSED); + + for (GList *iter = last_search; iter; iter = g_list_next(iter)) { + TBStatistics *tbs = iter->data; + tbs->stats_enabled = level; + } + + break; + default: /* INVALID */ + break; + } + + mmap_unlock(); + g_free(cmdinfo); +} diff --git a/hmp-commands.hx b/hmp-commands.hx index bfa5681dd2..419898751e 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -1885,6 +1885,23 @@ STEXI @findex qemu-io Executes a qemu-io command on the given block device. +ETEXI +#if defined(CONFIG_TCG) + { + .name = "tb_stats", + .args_type = "command:s,level:s?", + .params = "command [stats_level]", + .help = "Control tb statistics collection:" + "tb_stats (start|pause|stop|filter) [all|jit_stats|exec_stats]", + .cmd = hmp_tbstats, + }, +#endif + +STEXI +@item tb_stats +@findex +Control recording tb statistics + ETEXI { diff --git a/include/exec/tb-stats.h b/include/exec/tb-stats.h index 7d775f2c0d..d1debd3262 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" +enum SortBy { SORT_BY_HOTNESS, SORT_BY_HG /* Host/Guest */, SORT_BY_SPILLS }; +enum TbstatsCmd { START, PAUSE, STOP, FILTER }; + #define tb_stats_enabled(tb, JIT_STATS) \ (tb && tb->tb_stats && (tb->tb_stats->stats_enabled & JIT_STATS)) @@ -60,4 +63,14 @@ bool tb_stats_cmp(const void *ap, const void *bp); void dump_jit_profile_info(TCGProfile *s); +void set_tbstats_flags(uint32_t flags); +void clean_tbstats(void); + +struct TbstatsCommand { + enum TbstatsCmd cmd; + uint32_t level; +}; + +void do_hmp_tbstats_safe(CPUState *cpu, run_on_cpu_data icmd); + #endif diff --git a/include/qemu/log.h b/include/qemu/log.h index 93642603e5..47071d72c7 100644 --- a/include/qemu/log.h +++ b/include/qemu/log.h @@ -133,6 +133,7 @@ void qemu_log_close(void); #define TB_NOTHING 0 #define TB_EXEC_STATS (1 << 1) #define TB_JIT_STATS (1 << 2) +#define TB_PAUSED (1 << 3) void enable_collect_tb_stats(void); void disable_collect_tb_stats(void); diff --git a/monitor/misc.c b/monitor/misc.c index 00338c002a..aea9b0db4f 100644 --- a/monitor/misc.c +++ b/monitor/misc.c @@ -459,6 +459,46 @@ static void hmp_info_registers(Monitor *mon, const QDict *qdict) } #ifdef CONFIG_TCG +static void hmp_tbstats(Monitor *mon, const QDict *qdict) +{ + if (!tcg_enabled()) { + error_report("TB information is only available with accel=tcg"); + return; + } + + char *cmd = (char *) qdict_get_try_str(qdict, "command"); + enum TbstatsCmd icmd = -1; + + if (strcmp(cmd, "start") == 0) { + icmd = START; + } else if (strcmp(cmd, "pause") == 0) { + icmd = PAUSE; + } else if (strcmp(cmd, "stop") == 0) { + icmd = STOP; + } else if (strcmp(cmd, "filter") == 0) { + icmd = FILTER; + } else { + error_report("invalid command!"); + } + + char *slevel = (char *) qdict_get_try_str(qdict, "level"); + uint32_t level = TB_EXEC_STATS | TB_JIT_STATS; + if (slevel) { + if (strcmp(slevel, "jit_stats") == 0) { + level = TB_JIT_STATS; + } else if (strcmp(slevel, "exec_stats") == 0) { + level = TB_EXEC_STATS; + } + } + + struct TbstatsCommand *tbscommand = g_new0(struct TbstatsCommand, 1); + tbscommand->cmd = icmd; + tbscommand->level = level; + async_safe_run_on_cpu(first_cpu, do_hmp_tbstats_safe, + RUN_ON_CPU_HOST_PTR(tbscommand)); + +} + static void hmp_info_jit(Monitor *mon, const QDict *qdict) { if (!tcg_enabled()) {
Adding tb_stats [start|pause|stop|filter] command to hmp. This allows controlling the collection of statistics. It is also possible to set the level of collection: all, jit, or exec. The goal of this command is to allow the dynamic exploration of the TCG behavior and quality. Therefore, for now, a corresponding QMP command is not worthwhile. Signed-off-by: Vanderson M. do Rosario <vandersonmr2@gmail.com> --- accel/tcg/tb-stats.c | 107 ++++++++++++++++++++++++++++++++++++++++ hmp-commands.hx | 17 +++++++ include/exec/tb-stats.h | 13 +++++ include/qemu/log.h | 1 + monitor/misc.c | 40 +++++++++++++++ 5 files changed, 178 insertions(+)