This commit adds 'one-insn-per-tb' as a property on the TCG accelerator object, so you can enable it with -accel tcg,one-insn-per-tb=on It has the same behaviour as the existing '-singlestep' command line option. We use a different name because 'singlestep' has always been a confusing choice, because it doesn't have anything to do with single-stepping the CPU. What it does do is force TCG emulation to put one guest instruction in each TB, which can be useful in some situations (such as analysing debug logs). The existing '-singlestep' commandline options are decoupled from the global 'singlestep' variable and instead now are syntactic sugar for setting the accel property. (These can then go away after a deprecation period.) The global variable remains for the moment as: * what the TCG code looks at to change its behaviour * what HMP and QMP use to query and set the behaviour In the following commits we'll clean those up to not directly look at the global variable. Signed-off-by: Peter Maydell <peter.maydell(a)linaro.org&gt; --- accel/tcg/tcg-all.c | 21 +++++++++++++++++++++ bsd-user/main.c | 8 ++++++-- linux-user/main.c | 8 ++++++-- softmmu/vl.c | 17 +++++++++++++++-- qemu-options.hx | 7 +++++++ 5 files changed, 55 insertions(+), 6 deletions(-) diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c index 5dab1ae9dd3..fcf361c8db6 100644 --- a/accel/tcg/tcg-all.c +++ b/accel/tcg/tcg-all.c @@ -42,6 +42,7 @@ struct TCGState { AccelState parent_obj; bool mttcg_enabled; + bool one_insn_per_tb; int splitwx_enabled; unsigned long tb_size; }; @@ -208,6 +209,20 @@ static void tcg_set_splitwx(Object *obj, bool value, Error **errp) s->splitwx_enabled = value; } +static bool tcg_get_one_insn_per_tb(Object *obj, Error **errp) +{ + TCGState *s = TCG_STATE(obj); + return s->one_insn_per_tb; +} + +static void tcg_set_one_insn_per_tb(Object *obj, bool value, Error **errp) +{ + TCGState *s = TCG_STATE(obj); + s->one_insn_per_tb = value; + /* For the moment, set the global also: this changes the behaviour */ + singlestep = value; +} + static int tcg_gdbstub_supported_sstep_flags(void) { /* @@ -245,6 +260,12 @@ static void tcg_accel_class_init(ObjectClass *oc, void *data) tcg_get_splitwx, tcg_set_splitwx); object_class_property_set_description(oc, "split-wx", "Map jit pages into separate RW and RX regions"); + + object_class_property_add_bool(oc, "one-insn-per-tb", + tcg_get_one_insn_per_tb, + tcg_set_one_insn_per_tb); + object_class_property_set_description(oc, "one-insn-per-tb", + "Only put one guest insn in each translation block"); } static const TypeInfo tcg_accel_type = { diff --git a/bsd-user/main.c b/bsd-user/main.c index babc3b009b6..09b84da190c 100644 --- a/bsd-user/main.c +++ b/bsd-user/main.c @@ -50,6 +50,7 @@ #include "target_arch_cpu.h" int singlestep; +static bool opt_one_insn_per_tb; uintptr_t guest_base; bool have_guest_base; /* @@ -386,7 +387,7 @@ int main(int argc, char **argv) } else if (!strcmp(r, "seed")) { seed_optarg = optarg; } else if (!strcmp(r, "singlestep")) { - singlestep = 1; + opt_one_insn_per_tb = true; } else if (!strcmp(r, "strace")) { do_strace = 1; } else if (!strcmp(r, "trace")) { @@ -444,9 +445,12 @@ int main(int argc, char **argv) /* init tcg before creating CPUs and to get qemu_host_page_size */ { - AccelClass *ac = ACCEL_GET_CLASS(current_accel()); + AccelState *accel = current_accel(); + AccelClass *ac = ACCEL_GET_CLASS(accel); accel_init_interfaces(ac); + object_property_set_bool(OBJECT(accel), "one-insn-per-tb", + opt_one_insn_per_tb, &error_abort); ac->init_machine(NULL); } cpu = cpu_create(cpu_type); diff --git a/linux-user/main.c b/linux-user/main.c index fe03293516a..489694ad654 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -69,6 +69,7 @@ char *exec_path; char real_exec_path[PATH_MAX]; int singlestep; +static bool opt_one_insn_per_tb; static const char *argv0; static const char *gdbstub; static envlist_t *envlist; @@ -411,7 +412,7 @@ static void handle_arg_reserved_va(const char *arg) static void handle_arg_singlestep(const char *arg) { - singlestep = 1; + opt_one_insn_per_tb = true; } static void handle_arg_strace(const char *arg) @@ -777,9 +778,12 @@ int main(int argc, char **argv, char **envp) /* init tcg before creating CPUs and to get qemu_host_page_size */ { - AccelClass *ac = ACCEL_GET_CLASS(current_accel()); + AccelState *accel = current_accel(); + AccelClass *ac = ACCEL_GET_CLASS(accel); accel_init_interfaces(ac); + object_property_set_bool(OBJECT(accel), "one-insn-per-tb", + opt_one_insn_per_tb, &error_abort); ac->init_machine(NULL); } cpu = cpu_create(cpu_type); diff --git a/softmmu/vl.c b/softmmu/vl.c index ea20b23e4c8..492b5fe65e6 100644 --- a/softmmu/vl.c +++ b/softmmu/vl.c @@ -182,6 +182,7 @@ static const char *log_file; static bool list_data_dirs; static const char *qtest_chrdev; static const char *qtest_log; +static bool opt_one_insn_per_tb; static int has_defaults = 1; static int default_serial = 1; @@ -2220,7 +2221,19 @@ static int do_configure_accelerator(void *opaque, QemuOpts *opts, Error **errp) qemu_opt_foreach(opts, accelerator_set_property, accel, &error_fatal); - + /* + * If legacy -singlestep option is set, honour it for TCG and + * silently ignore for any other accelerator (which is how this + * option has always behaved). + */ + if (opt_one_insn_per_tb) { + /* + * This will always succeed for TCG, and we want to ignore + * the error from trying to set a nonexistent property + * on any other accelerator. + */ + object_property_set_bool(OBJECT(accel), "one-insn-per-tb", true, NULL); + } ret = accel_init_machine(accel, current_machine); if (ret < 0) { if (!qtest_with_kvm || ret != -ENOENT) { @@ -2955,7 +2968,7 @@ void qemu_init(int argc, char **argv) qdict_put_str(machine_opts_dict, "firmware", optarg); break; case QEMU_OPTION_singlestep: - singlestep = 1; + opt_one_insn_per_tb = true; break; case QEMU_OPTION_S: autostart = 0; diff --git a/qemu-options.hx b/qemu-options.hx index 59bdf67a2c5..1dffd36884e 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -182,6 +182,7 @@ DEF("accel", HAS_ARG, QEMU_OPTION_accel, " igd-passthru=on|off (enable Xen integrated Intel graphics passthrough, default=off)\n" " kernel-irqchip=on|off|split controls accelerated irqchip support (default=on)\n" " kvm-shadow-mem=size of KVM shadow MMU in bytes\n" + " one-insn-per-tb=on|off (one guest instruction per TCG translation block)\n" " split-wx=on|off (enable TCG split w^x mapping)\n" " tb-size=n (TCG translation block cache size)\n" " dirty-ring-size=n (KVM dirty ring GFN count, default 0)\n" @@ -210,6 +211,12 @@ SRST ``kvm-shadow-mem=size`` Defines the size of the KVM shadow MMU. + ``one-insn-per-tb=on|off`` + Makes the TCG accelerator put only one guest instruction into + each translation block. This slows down emulation a lot, but + can be useful in some situations, such as when trying to analyse + the logs produced by the ``-d`` option. + ``split-wx=on|off`` Controls the use of split w^x mapping for the TCG code generation buffer. Some operating systems require this to be enabled, and in -- 2.34.1

The HMP 'singlestep' command, the QMP 'query-status' command and the HMP 'info status' command (which is just wrapping the QMP command implementation) look at the 'singlestep' global variable. Make them access the new TCG accelerator 'one-insn-per-tb' property instead. This leaves the HMP and QMP command/field names and output strings unchanged; we will clean that up later. Signed-off-by: Peter Maydell <peter.maydell(a)linaro.org&gt; --- softmmu/runstate-hmp-cmds.c | 18 ++++++++++++++++-- softmmu/runstate.c | 10 +++++++++- 2 files changed, 25 insertions(+), 3 deletions(-) diff --git a/softmmu/runstate-hmp-cmds.c b/softmmu/runstate-hmp-cmds.c index d55a7d4db89..127521a483a 100644 --- a/softmmu/runstate-hmp-cmds.c +++ b/softmmu/runstate-hmp-cmds.c @@ -20,6 +20,7 @@ #include "qapi/error.h" #include "qapi/qapi-commands-run-state.h" #include "qapi/qmp/qdict.h" +#include "qemu/accel.h" void hmp_info_status(Monitor *mon, const QDict *qdict) { @@ -43,13 +44,26 @@ void hmp_info_status(Monitor *mon, const QDict *qdict) void hmp_singlestep(Monitor *mon, const QDict *qdict) { const char *option = qdict_get_try_str(qdict, "option"); + AccelState *accel = current_accel(); + bool newval; + + if (!object_property_find(OBJECT(accel), "one-insn-per-tb")) { + monitor_printf(mon, + "This accelerator does not support setting one-insn-per-tb\n"); + return; + } + if (!option || !strcmp(option, "on")) { - singlestep = 1; + newval = true; } else if (!strcmp(option, "off")) { - singlestep = 0; + newval = false; } else { monitor_printf(mon, "unexpected option %s\n", option); + return; } + /* If the property exists then setting it can never fail */ + object_property_set_bool(OBJECT(accel), "one-insn-per-tb", + newval, &error_abort); } void hmp_watchdog_action(Monitor *mon, const QDict *qdict) diff --git a/softmmu/runstate.c b/softmmu/runstate.c index d1e04586dbc..2f2396c819e 100644 --- a/softmmu/runstate.c +++ b/softmmu/runstate.c @@ -40,6 +40,7 @@ #include "qapi/error.h" #include "qapi/qapi-commands-run-state.h" #include "qapi/qapi-events-run-state.h" +#include "qemu/accel.h" #include "qemu/error-report.h" #include "qemu/job.h" #include "qemu/log.h" @@ -234,9 +235,16 @@ bool runstate_needs_reset(void) StatusInfo *qmp_query_status(Error **errp) { StatusInfo *info = g_malloc0(sizeof(*info)); + AccelState *accel = current_accel(); + /* + * We ignore errors, which will happen if the accelerator + * is not TCG. "singlestep" is meaningless for other accelerators, + * so we will set the StatusInfo field to false for those. + */ + info->singlestep = object_property_get_bool(OBJECT(accel), + "one-insn-per-tb", NULL); info->running = runstate_is_running(); - info->singlestep = singlestep; info->status = current_run_state; return info; -- 2.34.1

Change curr_cflags() to look at the one-insn-per-tb accelerator property instead of the old singlestep global variable. Since this is the final remaining use of the global, we can delete it entirely. Signed-off-by: Peter Maydell <peter.maydell(a)linaro.org&gt; --- This is the "clean" way of doing it. I dunno how much of a hot path curr_cflags is; if it's really critical we could have a global that's private to accel/tcg/internals.h I guess. --- accel/tcg/internal.h | 16 ++++++++++++++++ include/exec/cpu-common.h | 3 --- accel/tcg/cpu-exec.c | 5 +++-- accel/tcg/tcg-all.c | 17 ----------------- bsd-user/main.c | 1 - linux-user/main.c | 1 - softmmu/globals.c | 1 - 7 files changed, 19 insertions(+), 25 deletions(-) diff --git a/accel/tcg/internal.h b/accel/tcg/internal.h index 96f198b28b4..6ea5f7a295f 100644 --- a/accel/tcg/internal.h +++ b/accel/tcg/internal.h @@ -10,6 +10,22 @@ #define ACCEL_TCG_INTERNAL_H #include "exec/exec-all.h" +#include "qemu/accel.h" + +struct TCGState { + AccelState parent_obj; + + bool mttcg_enabled; + bool one_insn_per_tb; + int splitwx_enabled; + unsigned long tb_size; +}; +typedef struct TCGState TCGState; + +#define TYPE_TCG_ACCEL ACCEL_CLASS_NAME("tcg") + +DECLARE_INSTANCE_CHECKER(TCGState, TCG_STATE, + TYPE_TCG_ACCEL) /* * Access to the various translations structures need to be serialised diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h index 6feaa40ca7b..609a29a5dc2 100644 --- a/include/exec/cpu-common.h +++ b/include/exec/cpu-common.h @@ -162,9 +162,6 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length); int cpu_memory_rw_debug(CPUState *cpu, vaddr addr, void *ptr, size_t len, bool is_write); -/* vl.c */ -extern int singlestep; - void list_cpus(const char *optarg); #endif /* CPU_COMMON_H */ diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c index c815f2dbfdf..1ed3878b6b7 100644 --- a/accel/tcg/cpu-exec.c +++ b/accel/tcg/cpu-exec.c @@ -149,17 +149,18 @@ static void init_delay_params(SyncClocks *sc, const CPUState *cpu) uint32_t curr_cflags(CPUState *cpu) { uint32_t cflags = cpu->tcg_cflags; + TCGState *tcgstate = TCG_STATE(current_accel()); /* * Record gdb single-step. We should be exiting the TB by raising * EXCP_DEBUG, but to simplify other tests, disable chaining too. * - * For singlestep and -d nochain, suppress goto_tb so that + * For one-insn-per-tb and -d nochain, suppress goto_tb so that * we can log -d cpu,exec after every TB. */ if (unlikely(cpu->singlestep_enabled)) { cflags |= CF_NO_GOTO_TB | CF_NO_GOTO_PTR | CF_SINGLE_STEP | 1; - } else if (singlestep) { + } else if (tcgstate->one_insn_per_tb) { cflags |= CF_NO_GOTO_TB | 1; } else if (qemu_loglevel_mask(CPU_LOG_TB_NOCHAIN)) { cflags |= CF_NO_GOTO_TB; diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c index fcf361c8db6..7c4f9f34d39 100644 --- a/accel/tcg/tcg-all.c +++ b/accel/tcg/tcg-all.c @@ -38,21 +38,6 @@ #endif #include "internal.h" -struct TCGState { - AccelState parent_obj; - - bool mttcg_enabled; - bool one_insn_per_tb; - int splitwx_enabled; - unsigned long tb_size; -}; -typedef struct TCGState TCGState; - -#define TYPE_TCG_ACCEL ACCEL_CLASS_NAME("tcg") - -DECLARE_INSTANCE_CHECKER(TCGState, TCG_STATE, - TYPE_TCG_ACCEL) - /* * We default to false if we know other options have been enabled * which are currently incompatible with MTTCG. Otherwise when each @@ -219,8 +204,6 @@ static void tcg_set_one_insn_per_tb(Object *obj, bool value, Error **errp) { TCGState *s = TCG_STATE(obj); s->one_insn_per_tb = value; - /* For the moment, set the global also: this changes the behaviour */ - singlestep = value; } static int tcg_gdbstub_supported_sstep_flags(void) diff --git a/bsd-user/main.c b/bsd-user/main.c index 09b84da190c..a9e5a127d38 100644 --- a/bsd-user/main.c +++ b/bsd-user/main.c @@ -49,7 +49,6 @@ #include "host-os.h" #include "target_arch_cpu.h" -int singlestep; static bool opt_one_insn_per_tb; uintptr_t guest_base; bool have_guest_base; diff --git a/linux-user/main.c b/linux-user/main.c index 489694ad654..c7020b413bc 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -68,7 +68,6 @@ char *exec_path; char real_exec_path[PATH_MAX]; -int singlestep; static bool opt_one_insn_per_tb; static const char *argv0; static const char *gdbstub; diff --git a/softmmu/globals.c b/softmmu/globals.c index 39678aa8c58..e83b5428d12 100644 --- a/softmmu/globals.c +++ b/softmmu/globals.c @@ -43,7 +43,6 @@ int vga_interface_type = VGA_NONE; bool vga_interface_created; Chardev *parallel_hds[MAX_PARALLEL_PORTS]; int win2k_install_hack; -int singlestep; int fd_bootchk = 1; int graphic_rotate; QEMUOptionRom option_rom[MAX_OPTION_ROMS]; -- 2.34.1

The '-singlestep' option is confusing, because it doesn't actually have anything to do with single-stepping the CPU. What it does do is force TCG emulation to put one guest instruction in each TB, which can be useful in some situations. Create a new command line argument -one-insn-per-tb, so we can document that -singlestep is just a deprecated synonym for it, and eventually perhaps drop it. Signed-off-by: Peter Maydell <peter.maydell(a)linaro.org&gt; --- docs/user/main.rst | 7 ++++++- linux-user/main.c | 9 ++++++--- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/docs/user/main.rst b/docs/user/main.rst index 6f2ffa080f7..f9ac701f4b1 100644 --- a/docs/user/main.rst +++ b/docs/user/main.rst @@ -93,8 +93,13 @@ Debug options: ``-g port`` Wait gdb connection to port +``-one-insn-per-tb`` + Run the emulation with one guest instruction per translation block. + This slows down emulation a lot, but can be useful in some situations, + such as when trying to analyse the logs produced by the ``-d`` option. + ``-singlestep`` - Run the emulation in single step mode. + This is a deprecated synonym for the ``-one-insn-per-tb`` option. Environment variables: diff --git a/linux-user/main.c b/linux-user/main.c index c7020b413bc..5defe5a6db8 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -409,7 +409,7 @@ static void handle_arg_reserved_va(const char *arg) reserved_va = val ? val - 1 : 0; } -static void handle_arg_singlestep(const char *arg) +static void handle_arg_one_insn_per_tb(const char *arg) { opt_one_insn_per_tb = true; } @@ -500,8 +500,11 @@ static const struct qemu_argument arg_table[] = { "logfile", "write logs to 'logfile' (default stderr)"}, {"p", "QEMU_PAGESIZE", true, handle_arg_pagesize, "pagesize", "set the host page size to 'pagesize'"}, - {"singlestep", "QEMU_SINGLESTEP", false, handle_arg_singlestep, - "", "run in singlestep mode"}, + {"one-insn-per-tb", + "QEMU_ONE_INSN_PER_TB", false, handle_arg_one_insn_per_tb, + "", "run with one guest instruction per emulated TB"}, + {"singlestep", "QEMU_SINGLESTEP", false, handle_arg_one_insn_per_tb, + "", "deprecated synonym for -one-insn-per-tb"}, {"strace", "QEMU_STRACE", false, handle_arg_strace, "", "log system calls"}, {"seed", "QEMU_RAND_SEED", true, handle_arg_seed, -- 2.34.1

Document that the -singlestep command line option is now deprecated, as it is replaced by either the TCG accelerator property 'one-insn-per-tb' for system emulation or the new '-one-insn-per-tb' option for usermode emulation, and remove the only use of the deprecated syntax from a README. Signed-off-by: Peter Maydell <peter.maydell(a)linaro.org&gt; --- docs/about/deprecated.rst | 16 ++++++++++++++++ qemu-options.hx | 5 +++-- tcg/tci/README | 2 +- 3 files changed, 20 insertions(+), 3 deletions(-) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 1ca9dc33d61..3c62671dac1 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -111,6 +111,22 @@ Use ``-machine acpi=off`` instead. The HAXM project has been retired (see https://github.com/intel/haxm#status). Use "whpx" (on Windows) or "hvf" (on macOS) instead. +``-singlestep`` (since 8.1) +''''''''''''''''''''''''''' + +The ``-singlestep`` option has been turned into an accelerator property, +and given a name that better reflects what it actually does. +Use ``-accel tcg,one-insn-per-tb=on`` instead. + +User-mode emulator command line arguments +----------------------------------------- + +``-singlestep`` (since 8.1) +''''''''''''''''''''''''''' + +The ``-singlestep`` option has been given a name that better reflects +what it actually does. For both linux-user and bsd-user, use the +new ``-one-insn-per-tb`` option instead. QEMU Machine Protocol (QMP) commands ------------------------------------ diff --git a/qemu-options.hx b/qemu-options.hx index 1dffd36884e..6a59e997497 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4159,10 +4159,11 @@ SRST ERST DEF("singlestep", 0, QEMU_OPTION_singlestep, \ - "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) + "-singlestep deprecated synonym for -accel tcg,one-insn-per-tb=on\n", QEMU_ARCH_ALL) SRST ``-singlestep`` - Run the emulation in single step mode. + This is a deprecated synonym for the TCG accelerator property + ``one-insn-per-tb``. ERST DEF("preconfig", 0, QEMU_OPTION_preconfig, \ diff --git a/tcg/tci/README b/tcg/tci/README index f72a40a395a..4a8b5b54018 100644 --- a/tcg/tci/README +++ b/tcg/tci/README @@ -49,7 +49,7 @@ The only difference from running QEMU with TCI to running without TCI should be speed. Especially during development of TCI, it was very useful to compare runs with and without TCI. Create /tmp/qemu.log by - qemu-system-i386 -d in_asm,op_opt,cpu -D /tmp/qemu.log -singlestep + qemu-system-i386 -d in_asm,op_opt,cpu -D /tmp/qemu.log -accel tcg,one-insn-per-tb=on once with interpreter and once without interpreter and compare the resulting qemu.log files. This is also useful to see the effects of additional -- 2.34.1

The 'singlestep' HMP command is confusing, because it doesn't actually have anything to do with single-stepping the CPU. What it does do is force TCG emulation to put one guest instruction in each TB, which can be useful in some situations. Create a new HMP command 'one-insn-per-tb', so we can document that 'singlestep' is just a deprecated synonym for it, and eventually perhaps drop it. We aren't obliged to do deprecate-and-drop for HMP commands, but it's easy enough to do so, so we do. Signed-off-by: Peter Maydell <peter.maydell(a)linaro.org&gt; --- docs/about/deprecated.rst | 9 +++++++++ include/monitor/hmp.h | 2 +- softmmu/runstate-hmp-cmds.c | 2 +- tests/qtest/test-hmp.c | 1 + hmp-commands.hx | 25 +++++++++++++++++++++---- 5 files changed, 33 insertions(+), 6 deletions(-) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 3c62671dac1..6f5e689aa45 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -199,6 +199,15 @@ accepted incorrect commands will return an error. Users should make sure that all arguments passed to ``device_add`` are consistent with the documented property types. +Human Monitor Protocol (HMP) commands +------------------------------------- + +``singlestep`` (since 8.1) +'''''''''''''''''''''''''' + +The ``singlestep`` command has been replaced by the ``one-insn-per-tb`` +command, which has the same behaviour but a less misleading name. + Host Architectures ------------------ diff --git a/include/monitor/hmp.h b/include/monitor/hmp.h index fdb69b7f9ca..13f9a2dedb8 100644 --- a/include/monitor/hmp.h +++ b/include/monitor/hmp.h @@ -158,7 +158,7 @@ void hmp_info_vcpu_dirty_limit(Monitor *mon, const QDict *qdict); void hmp_human_readable_text_helper(Monitor *mon, HumanReadableText *(*qmp_handler)(Error **)); void hmp_info_stats(Monitor *mon, const QDict *qdict); -void hmp_singlestep(Monitor *mon, const QDict *qdict); +void hmp_one_insn_per_tb(Monitor *mon, const QDict *qdict); void hmp_watchdog_action(Monitor *mon, const QDict *qdict); void hmp_pcie_aer_inject_error(Monitor *mon, const QDict *qdict); void hmp_info_capture(Monitor *mon, const QDict *qdict); diff --git a/softmmu/runstate-hmp-cmds.c b/softmmu/runstate-hmp-cmds.c index 127521a483a..76d1399ed85 100644 --- a/softmmu/runstate-hmp-cmds.c +++ b/softmmu/runstate-hmp-cmds.c @@ -41,7 +41,7 @@ void hmp_info_status(Monitor *mon, const QDict *qdict) qapi_free_StatusInfo(info); } -void hmp_singlestep(Monitor *mon, const QDict *qdict) +void hmp_one_insn_per_tb(Monitor *mon, const QDict *qdict) { const char *option = qdict_get_try_str(qdict, "option"); AccelState *accel = current_accel(); diff --git a/tests/qtest/test-hmp.c b/tests/qtest/test-hmp.c index b4a920df898..cb3530df722 100644 --- a/tests/qtest/test-hmp.c +++ b/tests/qtest/test-hmp.c @@ -64,6 +64,7 @@ static const char *hmp_cmds[] = { "screendump /dev/null", "sendkey x", "singlestep on", + "one-insn-per-tb on", "wavcapture /dev/null", "stopcapture 0", "sum 0 512", diff --git a/hmp-commands.hx b/hmp-commands.hx index bb85ee1d267..9afbb54a515 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -378,18 +378,35 @@ SRST only *tag* as parameter. ERST + { + .name = "one-insn-per-tb", + .args_type = "option:s?", + .params = "[on|off]", + .help = "run emulation with one guest instruction per translation block", + .cmd = hmp_one_insn_per_tb, + }, + +SRST +``one-insn-per-tb [off]`` + Run the emulation with one guest instruction per translation block. + This slows down emulation a lot, but can be useful in some situations, + such as when trying to analyse the logs produced by the ``-d`` option. + This only has an effect when using TCG, not with KVM or other accelerators. + + If called with option off, the emulation returns to normal mode. +ERST + { .name = "singlestep", .args_type = "option:s?", .params = "[on|off]", - .help = "run emulation in singlestep mode or switch to normal mode", - .cmd = hmp_singlestep, + .help = "deprecated synonym for one-insn-per-tb", + .cmd = hmp_one_insn_per_tb, }, SRST ``singlestep [off]`` - Run the emulation in single step mode. - If called with option off, the emulation returns to normal mode. + This is a deprecated synonym for the one-insn-per-tb command. ERST { -- 2.34.1

In the title: "qmp:" Peter Maydell <peter.maydell(a)linaro.org&gt; writes: Wrap this line, please. Hmm. We report it in query-status, which means it's relevant to QMP clients. We provide the command to control it only in HMP, which means it's not relevant to QMP clients. Why is reading it relevant to QMP clients, but not writing? Use cases for reading it via QMP query-status? Have you considered tacking feature 'unstable' to it? I see a bunch of query-status results in tests/qemu-iotests/{183,234,262,280}.out. Do they need an update? [...]

Peter Maydell <peter.maydell(a)linaro.org&gt; writes: Kind of. Here's my current boilerplate on the subject: HMP commands without a QMP equivalent are okay if their functionality makes no sense in QMP, or is of use only for human users. Example for "makes no sense in QMP": setting the current CPU, because a QMP monitor doesn't have a current CPU. Examples for "is of use only for human users": HMP command "help", the integrated pocket calculator. Debugging commands are kind of borderline. Debugging is commonly a human activity, where HMP is just fine. However, humans create tools to assist with their activities, and then QMP is useful. While I wouldn't encourage HMP-only for the debugging use case, I wouldn't veto it. When adding an HMP-only command, explain why it is HMP-only in the commit message. How useful is it HMP? docs/devel/qapi-code-gen.rst explains: Special features ~~~~~~~~~~~~~~~~ Feature "deprecated" marks a command, event, enum value, or struct member as deprecated. It is not supported elsewhere so far. Interfaces so marked may be withdrawn in future releases in accordance with QEMU's deprecation policy. Feature "unstable" marks a command, event, enum value, or struct member as unstable. It is not supported elsewhere so far. Interfaces so marked may be withdrawn or changed incompatibly in future releases. We use "unstable" for debugging aids, testing aids, experiments / unfinished work. Plenty of iotests don't run in "make check". Try $ tests/qemu-iotests/check -qcow2 183 234 262 280 If (hazy) memory serves, there's some normalization. I doubt it'll affect this member, i.e. you need to put it there.