Message ID | 20200227161454.32368-1-imammedo@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | [v2] softmmu/vl.c: fix too slow TCG regression | expand |
Can we improve the patch subject? "vl: Fix slower TCG on softmmu" or better? On 2/27/20 5:14 PM, Igor Mammedov wrote: > Commit a1b18df9a4 moved -m option parsing after configure_accelerators() > that broke TCG accelerator initialization which accesses global ram_size > from size_code_gen_buffer() which is equal to 0 at that moment. > > Partially revert a1b18df9a4, by returning set_memory_options() to its > original location and only keep 32-bit host VA check and 'memory-backend' > size check introduced by fe64d06afc at current place. > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com> > --- > v2: > * check if user used -m SZ before comparing ram_size with backend's size. > Fixes case where qemu exits with error when backend's size doesn't match > dafault ram_size (i.e. user haven't used -m option at all) > (Peter Maydell <peter.maydell@linaro.org>) > * keep order addr space size check for 32-bit host after > backend size check. So it would be affected by backend's size as well. > --- > softmmu/vl.c | 54 ++++++++++++++++++++++++++++------------------------ > 1 file changed, 29 insertions(+), 25 deletions(-) > > diff --git a/softmmu/vl.c b/softmmu/vl.c > index a9cce78f45..16ff5a16a3 100644 > --- a/softmmu/vl.c > +++ b/softmmu/vl.c > @@ -2558,7 +2558,7 @@ static bool object_create_delayed(const char *type, QemuOpts *opts) > } > > > -static void set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, > +static bool set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, > MachineClass *mc) > { > uint64_t sz; > @@ -2634,30 +2634,8 @@ static void set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, > exit(EXIT_FAILURE); > } > > - if (current_machine->ram_memdev_id) { > - Object *backend; > - ram_addr_t backend_size; > - > - backend = object_resolve_path_type(current_machine->ram_memdev_id, > - TYPE_MEMORY_BACKEND, NULL); > - backend_size = object_property_get_uint(backend, "size", &error_abort); > - if (mem_str && backend_size != ram_size) { > - error_report("Size specified by -m option must match size of " > - "explicitly specified 'memory-backend' property"); > - exit(EXIT_FAILURE); > - } > - ram_size = backend_size; > - } > - > - if (!xen_enabled()) { > - /* On 32-bit hosts, QEMU is limited by virtual address space */ > - if (ram_size > (2047 << 20) && HOST_LONG_BITS == 32) { > - error_report("at most 2047 MB RAM can be simulated"); > - exit(1); > - } > - } > - > loc_pop(&loc); > + return !!mem_str; > } > > static int global_init_func(void *opaque, QemuOpts *opts, Error **errp) > @@ -2861,6 +2839,7 @@ void qemu_init(int argc, char **argv, char **envp) > bool list_data_dirs = false; > char *dir, **dirs; > const char *mem_path = NULL; > + bool have_custom_ram_size; > BlockdevOptionsQueue bdo_queue = QSIMPLEQ_HEAD_INITIALIZER(bdo_queue); > QemuPluginList plugin_list = QTAILQ_HEAD_INITIALIZER(plugin_list); > int mem_prealloc = 0; /* force preallocation of physical target memory */ > @@ -3821,6 +3800,9 @@ void qemu_init(int argc, char **argv, char **envp) > machine_class = select_machine(); > object_set_machine_compat_props(machine_class->compat_props); > > + have_custom_ram_size = set_memory_options(&ram_slots, &maxram_size, > + machine_class); > + > os_daemonize(); > > /* > @@ -4296,7 +4278,29 @@ void qemu_init(int argc, char **argv, char **envp) > current_machine->cpu_type = parse_cpu_option(cpu_option); > } > > - set_memory_options(&ram_slots, &maxram_size, machine_class); > + if (current_machine->ram_memdev_id) { > + Object *backend; > + ram_addr_t backend_size; > + > + backend = object_resolve_path_type(current_machine->ram_memdev_id, > + TYPE_MEMORY_BACKEND, NULL); > + backend_size = object_property_get_uint(backend, "size", &error_abort); > + if (have_custom_ram_size && backend_size != ram_size) { > + error_report("Size specified by -m option must match size of " > + "explicitly specified 'memory-backend' property"); > + exit(EXIT_FAILURE); > + } > + ram_size = backend_size; > + } > + > + if (!xen_enabled()) { > + /* On 32-bit hosts, QEMU is limited by virtual address space */ > + if (ram_size > (2047 << 20) && HOST_LONG_BITS == 32) { > + error_report("at most 2047 MB RAM can be simulated"); > + exit(1); > + } > + } > + > current_machine->ram_size = ram_size; > current_machine->maxram_size = maxram_size; > current_machine->ram_slots = ram_slots; >
On 2/27/20 5:14 PM, Igor Mammedov wrote: > Commit a1b18df9a4 moved -m option parsing after configure_accelerators() > that broke TCG accelerator initialization which accesses global ram_size > from size_code_gen_buffer() which is equal to 0 at that moment. > > Partially revert a1b18df9a4, by returning set_memory_options() to its > original location and only keep 32-bit host VA check and 'memory-backend' > size check introduced by fe64d06afc at current place. > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > --- > v2: > * check if user used -m SZ before comparing ram_size with backend's size. > Fixes case where qemu exits with error when backend's size doesn't match > dafault ram_size (i.e. user haven't used -m option at all) > (Peter Maydell <peter.maydell@linaro.org>) > * keep order addr space size check for 32-bit host after > backend size check. So it would be affected by backend's size as well. > --- > softmmu/vl.c | 54 ++++++++++++++++++++++++++++------------------------ > 1 file changed, 29 insertions(+), 25 deletions(-) > > diff --git a/softmmu/vl.c b/softmmu/vl.c > index a9cce78f45..16ff5a16a3 100644 > --- a/softmmu/vl.c > +++ b/softmmu/vl.c > @@ -2558,7 +2558,7 @@ static bool object_create_delayed(const char *type, QemuOpts *opts) > } > > > -static void set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, > +static bool set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, > MachineClass *mc) > { > uint64_t sz; > @@ -2634,30 +2634,8 @@ static void set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, > exit(EXIT_FAILURE); > } > > - if (current_machine->ram_memdev_id) { > - Object *backend; > - ram_addr_t backend_size; > - > - backend = object_resolve_path_type(current_machine->ram_memdev_id, > - TYPE_MEMORY_BACKEND, NULL); > - backend_size = object_property_get_uint(backend, "size", &error_abort); > - if (mem_str && backend_size != ram_size) { > - error_report("Size specified by -m option must match size of " > - "explicitly specified 'memory-backend' property"); > - exit(EXIT_FAILURE); > - } > - ram_size = backend_size; > - } > - > - if (!xen_enabled()) { > - /* On 32-bit hosts, QEMU is limited by virtual address space */ > - if (ram_size > (2047 << 20) && HOST_LONG_BITS == 32) { > - error_report("at most 2047 MB RAM can be simulated"); > - exit(1); > - } > - } > - > loc_pop(&loc); > + return !!mem_str; > } > > static int global_init_func(void *opaque, QemuOpts *opts, Error **errp) > @@ -2861,6 +2839,7 @@ void qemu_init(int argc, char **argv, char **envp) > bool list_data_dirs = false; > char *dir, **dirs; > const char *mem_path = NULL; > + bool have_custom_ram_size; > BlockdevOptionsQueue bdo_queue = QSIMPLEQ_HEAD_INITIALIZER(bdo_queue); > QemuPluginList plugin_list = QTAILQ_HEAD_INITIALIZER(plugin_list); > int mem_prealloc = 0; /* force preallocation of physical target memory */ > @@ -3821,6 +3800,9 @@ void qemu_init(int argc, char **argv, char **envp) > machine_class = select_machine(); > object_set_machine_compat_props(machine_class->compat_props); > > + have_custom_ram_size = set_memory_options(&ram_slots, &maxram_size, > + machine_class); > + > os_daemonize(); > > /* > @@ -4296,7 +4278,29 @@ void qemu_init(int argc, char **argv, char **envp) > current_machine->cpu_type = parse_cpu_option(cpu_option); > } > > - set_memory_options(&ram_slots, &maxram_size, machine_class); > + if (current_machine->ram_memdev_id) { > + Object *backend; > + ram_addr_t backend_size; > + > + backend = object_resolve_path_type(current_machine->ram_memdev_id, > + TYPE_MEMORY_BACKEND, NULL); > + backend_size = object_property_get_uint(backend, "size", &error_abort); > + if (have_custom_ram_size && backend_size != ram_size) { > + error_report("Size specified by -m option must match size of " > + "explicitly specified 'memory-backend' property"); > + exit(EXIT_FAILURE); > + } > + ram_size = backend_size; > + } > + > + if (!xen_enabled()) { > + /* On 32-bit hosts, QEMU is limited by virtual address space */ > + if (ram_size > (2047 << 20) && HOST_LONG_BITS == 32) { > + error_report("at most 2047 MB RAM can be simulated"); > + exit(1); > + } > + } > + > current_machine->ram_size = ram_size; > current_machine->maxram_size = maxram_size; > current_machine->ram_slots = ram_slots; > Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
On Thu, 27 Feb 2020 at 16:15, Igor Mammedov <imammedo@redhat.com> wrote: > > Commit a1b18df9a4 moved -m option parsing after configure_accelerators() > that broke TCG accelerator initialization which accesses global ram_size > from size_code_gen_buffer() which is equal to 0 at that moment. > > Partially revert a1b18df9a4, by returning set_memory_options() to its > original location and only keep 32-bit host VA check and 'memory-backend' > size check introduced by fe64d06afc at current place. > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > --- > v2: > * check if user used -m SZ before comparing ram_size with backend's size. > Fixes case where qemu exits with error when backend's size doesn't match > dafault ram_size (i.e. user haven't used -m option at all) > (Peter Maydell <peter.maydell@linaro.org>) > * keep order addr space size check for 32-bit host after > backend size check. So it would be affected by backend's size as well. Applied to master as a fix for the tcg perf regression, thanks. -- PMM
diff --git a/softmmu/vl.c b/softmmu/vl.c index a9cce78f45..16ff5a16a3 100644 --- a/softmmu/vl.c +++ b/softmmu/vl.c @@ -2558,7 +2558,7 @@ static bool object_create_delayed(const char *type, QemuOpts *opts) } -static void set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, +static bool set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, MachineClass *mc) { uint64_t sz; @@ -2634,30 +2634,8 @@ static void set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size, exit(EXIT_FAILURE); } - if (current_machine->ram_memdev_id) { - Object *backend; - ram_addr_t backend_size; - - backend = object_resolve_path_type(current_machine->ram_memdev_id, - TYPE_MEMORY_BACKEND, NULL); - backend_size = object_property_get_uint(backend, "size", &error_abort); - if (mem_str && backend_size != ram_size) { - error_report("Size specified by -m option must match size of " - "explicitly specified 'memory-backend' property"); - exit(EXIT_FAILURE); - } - ram_size = backend_size; - } - - if (!xen_enabled()) { - /* On 32-bit hosts, QEMU is limited by virtual address space */ - if (ram_size > (2047 << 20) && HOST_LONG_BITS == 32) { - error_report("at most 2047 MB RAM can be simulated"); - exit(1); - } - } - loc_pop(&loc); + return !!mem_str; } static int global_init_func(void *opaque, QemuOpts *opts, Error **errp) @@ -2861,6 +2839,7 @@ void qemu_init(int argc, char **argv, char **envp) bool list_data_dirs = false; char *dir, **dirs; const char *mem_path = NULL; + bool have_custom_ram_size; BlockdevOptionsQueue bdo_queue = QSIMPLEQ_HEAD_INITIALIZER(bdo_queue); QemuPluginList plugin_list = QTAILQ_HEAD_INITIALIZER(plugin_list); int mem_prealloc = 0; /* force preallocation of physical target memory */ @@ -3821,6 +3800,9 @@ void qemu_init(int argc, char **argv, char **envp) machine_class = select_machine(); object_set_machine_compat_props(machine_class->compat_props); + have_custom_ram_size = set_memory_options(&ram_slots, &maxram_size, + machine_class); + os_daemonize(); /* @@ -4296,7 +4278,29 @@ void qemu_init(int argc, char **argv, char **envp) current_machine->cpu_type = parse_cpu_option(cpu_option); } - set_memory_options(&ram_slots, &maxram_size, machine_class); + if (current_machine->ram_memdev_id) { + Object *backend; + ram_addr_t backend_size; + + backend = object_resolve_path_type(current_machine->ram_memdev_id, + TYPE_MEMORY_BACKEND, NULL); + backend_size = object_property_get_uint(backend, "size", &error_abort); + if (have_custom_ram_size && backend_size != ram_size) { + error_report("Size specified by -m option must match size of " + "explicitly specified 'memory-backend' property"); + exit(EXIT_FAILURE); + } + ram_size = backend_size; + } + + if (!xen_enabled()) { + /* On 32-bit hosts, QEMU is limited by virtual address space */ + if (ram_size > (2047 << 20) && HOST_LONG_BITS == 32) { + error_report("at most 2047 MB RAM can be simulated"); + exit(1); + } + } + current_machine->ram_size = ram_size; current_machine->maxram_size = maxram_size; current_machine->ram_slots = ram_slots;
Commit a1b18df9a4 moved -m option parsing after configure_accelerators() that broke TCG accelerator initialization which accesses global ram_size from size_code_gen_buffer() which is equal to 0 at that moment. Partially revert a1b18df9a4, by returning set_memory_options() to its original location and only keep 32-bit host VA check and 'memory-backend' size check introduced by fe64d06afc at current place. Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- v2: * check if user used -m SZ before comparing ram_size with backend's size. Fixes case where qemu exits with error when backend's size doesn't match dafault ram_size (i.e. user haven't used -m option at all) (Peter Maydell <peter.maydell@linaro.org>) * keep order addr space size check for 32-bit host after backend size check. So it would be affected by backend's size as well. --- softmmu/vl.c | 54 ++++++++++++++++++++++++++++------------------------ 1 file changed, 29 insertions(+), 25 deletions(-)