| Message ID | 1516203816-19374-21-git-send-email-imammedo@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | generalize parsing of cpu_model (part 4) | expand |
On Wed, Jan 17, 2018 at 04:43:32PM +0100, Igor Mammedov wrote: > The last user of it was machine type 'none', which used field > to create CPU id user requested it on CLI with -cpu option. > > We could compare pointers of MachineState::cpu_type and > MachineClass::default_cpu_type to check for the same condition, > and drop cpu_model concept completly from machine/boards code > So that no one would try to reuse obsolete field and only > place to deal with cpu model would be vl.c and > foo_cpu_class_by_name() callbacks. > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > --- > CC: Eduardo Habkost <ehabkost@redhat.com> > CC: Marcel Apfelbaum <marcel@redhat.com> > CC: Paolo Bonzini <pbonzini@redhat.com> > --- > include/hw/boards.h | 1 - > hw/core/null-machine.c | 10 +++++++--- > vl.c | 8 +++++++- > 3 files changed, 14 insertions(+), 5 deletions(-) > > diff --git a/include/hw/boards.h b/include/hw/boards.h > index 156b16f..decd0ec 100644 > --- a/include/hw/boards.h > +++ b/include/hw/boards.h > @@ -246,7 +246,6 @@ struct MachineState { > char *kernel_filename; > char *kernel_cmdline; > char *initrd_filename; > - const char *cpu_model; > const char *cpu_type; > AccelState *accelerator; > CPUArchIdList *possible_cpus; > diff --git a/hw/core/null-machine.c b/hw/core/null-machine.c > index 864832d..c2e466c 100644 > --- a/hw/core/null-machine.c > +++ b/hw/core/null-machine.c > @@ -23,10 +23,13 @@ > static void machine_none_init(MachineState *mch) > { > CPUState *cpu = NULL; > + MachineClass *mc = MACHINE_GET_CLASS(mch); > > - /* Initialize CPU (if a model has been specified) */ > - if (mch->cpu_model) { > - cpu = cpu_init(mch->cpu_model); > + /* Initialize CPU if cpu_type pointer is user provided > + * (i.e. != to pointer tot static default cpu type string) > + */ > + if (mch->cpu_type != mc->default_cpu_type) { > + cpu = cpu_create(mch->cpu_type); This is a big assumption about the code that sets mch->cpu_type. A simple g_strdup(machine_class->default_cpu_type) would break this silently (as it won't trigger the assert() below). > if (!cpu) { > error_report("Unable to initialize CPU"); > exit(1); > @@ -54,6 +57,7 @@ static void machine_none_machine_init(MachineClass *mc) > mc->init = machine_none_init; > mc->max_cpus = 1; > mc->default_ram_size = 0; > + mc->default_cpu_type = TARGET_DEFAULT_CPU_TYPE; Why do you need this? Isn't it simpler to just leave default_cpu_type=NULL here? > } > > DEFINE_MACHINE("none", machine_none_machine_init) > diff --git a/vl.c b/vl.c > index 2586f25..8aa0131 100644 > --- a/vl.c > +++ b/vl.c > @@ -4609,7 +4609,6 @@ int main(int argc, char **argv, char **envp) > current_machine->maxram_size = maxram_size; > current_machine->ram_slots = ram_slots; > current_machine->boot_order = boot_order; > - current_machine->cpu_model = cpu_model; > > parse_numa_opts(current_machine); > > @@ -4619,6 +4618,13 @@ int main(int argc, char **argv, char **envp) > if (cpu_model) { > current_machine->cpu_type = > cpu_parse_cpu_model(machine_class->default_cpu_type, cpu_model); > + > + /* machine 'none' depends on default cpu type pointer not being > + * equal to resolved type name pointer to fugure out if type was > + * user provided, make sure that if it becomes not true in future > + * it won't beark silently */ > + g_assert( > + current_machine->cpu_type != machine_class->default_cpu_type); > } > } > > -- > 2.7.4 >
On Wed, 17 Jan 2018 23:48:46 -0200 Eduardo Habkost <ehabkost@redhat.com> wrote: > On Wed, Jan 17, 2018 at 04:43:32PM +0100, Igor Mammedov wrote: > > The last user of it was machine type 'none', which used field > > to create CPU id user requested it on CLI with -cpu option. > > > > We could compare pointers of MachineState::cpu_type and > > MachineClass::default_cpu_type to check for the same condition, > > and drop cpu_model concept completly from machine/boards code > > So that no one would try to reuse obsolete field and only > > place to deal with cpu model would be vl.c and > > foo_cpu_class_by_name() callbacks. > > > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > > --- > > CC: Eduardo Habkost <ehabkost@redhat.com> > > CC: Marcel Apfelbaum <marcel@redhat.com> > > CC: Paolo Bonzini <pbonzini@redhat.com> > > --- > > include/hw/boards.h | 1 - > > hw/core/null-machine.c | 10 +++++++--- > > vl.c | 8 +++++++- > > 3 files changed, 14 insertions(+), 5 deletions(-) > > > > diff --git a/include/hw/boards.h b/include/hw/boards.h > > index 156b16f..decd0ec 100644 > > --- a/include/hw/boards.h > > +++ b/include/hw/boards.h > > @@ -246,7 +246,6 @@ struct MachineState { > > char *kernel_filename; > > char *kernel_cmdline; > > char *initrd_filename; > > - const char *cpu_model; > > const char *cpu_type; > > AccelState *accelerator; > > CPUArchIdList *possible_cpus; > > diff --git a/hw/core/null-machine.c b/hw/core/null-machine.c > > index 864832d..c2e466c 100644 > > --- a/hw/core/null-machine.c > > +++ b/hw/core/null-machine.c > > @@ -23,10 +23,13 @@ > > static void machine_none_init(MachineState *mch) > > { > > CPUState *cpu = NULL; > > + MachineClass *mc = MACHINE_GET_CLASS(mch); > > > > - /* Initialize CPU (if a model has been specified) */ > > - if (mch->cpu_model) { > > - cpu = cpu_init(mch->cpu_model); > > + /* Initialize CPU if cpu_type pointer is user provided > > + * (i.e. != to pointer tot static default cpu type string) > > + */ > > + if (mch->cpu_type != mc->default_cpu_type) { > > + cpu = cpu_create(mch->cpu_type); > > This is a big assumption about the code that sets mch->cpu_type. > A simple g_strdup(machine_class->default_cpu_type) would break > this silently (as it won't trigger the assert() below). Yes, it's a bit of a hack to figure out is user has requested cpu type explicitly. But so far there isn't need to do g_strdup(machine_class->default_cpu_type) when copying default in vl.c and guarding against it looks like overkill currently. Cleaner way would be to make cpu_type property, add new property API to set/check flags and use that here, there are other places that would benefit from such API as well. But it looks beyond scope of this series, so I used simple hackish way to make it work with current code. I can amend comment here: /* Initialize CPU if cpu_type pointer is user provided * (i.e. != to pointer to static default cpu type string) * MachineClass::default_cpu_type must be assigned to * MachineState::cpu_type directly for this to work. * TODO: * - make cpu_type a property * - add API to add/check user_set flag to property * - use new API to check if property was user set */ > > > > if (!cpu) { > > error_report("Unable to initialize CPU"); > > exit(1); > > @@ -54,6 +57,7 @@ static void machine_none_machine_init(MachineClass *mc) > > mc->init = machine_none_init; > > mc->max_cpus = 1; > > mc->default_ram_size = 0; > > + mc->default_cpu_type = TARGET_DEFAULT_CPU_TYPE; > > Why do you need this? Isn't it simpler to just leave > default_cpu_type=NULL here? vl.c "-cpu" parsing depends on default_cpu_type being set ... if (machine_class->default_cpu_type) { ... } when we get rid of requirement for proxy type in cpu_parse_cpu_model() we can drop this ugliness in null-machine. I'm doing it dirty way to prevent cpu_model resurgence in boards code as it happened with nios2, even though I've tried to monitor list for such patches. > > } > > > > DEFINE_MACHINE("none", machine_none_machine_init) > > diff --git a/vl.c b/vl.c > > index 2586f25..8aa0131 100644 > > --- a/vl.c > > +++ b/vl.c > > @@ -4609,7 +4609,6 @@ int main(int argc, char **argv, char **envp) > > current_machine->maxram_size = maxram_size; > > current_machine->ram_slots = ram_slots; > > current_machine->boot_order = boot_order; > > - current_machine->cpu_model = cpu_model; > > > > parse_numa_opts(current_machine); > > > > @@ -4619,6 +4618,13 @@ int main(int argc, char **argv, char **envp) > > if (cpu_model) { > > current_machine->cpu_type = > > cpu_parse_cpu_model(machine_class->default_cpu_type, cpu_model); > > + > > + /* machine 'none' depends on default cpu type pointer not being > > + * equal to resolved type name pointer to fugure out if type was > > + * user provided, make sure that if it becomes not true in future > > + * it won't beark silently */ > > + g_assert( > > + current_machine->cpu_type != machine_class->default_cpu_type); > > } > > } > > > > -- > > 2.7.4 > > >
On Thu, Jan 18, 2018 at 11:10:35AM +0100, Igor Mammedov wrote: > On Wed, 17 Jan 2018 23:48:46 -0200 > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > On Wed, Jan 17, 2018 at 04:43:32PM +0100, Igor Mammedov wrote: > > > The last user of it was machine type 'none', which used field > > > to create CPU id user requested it on CLI with -cpu option. > > > > > > We could compare pointers of MachineState::cpu_type and > > > MachineClass::default_cpu_type to check for the same condition, > > > and drop cpu_model concept completly from machine/boards code > > > So that no one would try to reuse obsolete field and only > > > place to deal with cpu model would be vl.c and > > > foo_cpu_class_by_name() callbacks. > > > > > > Signed-off-by: Igor Mammedov <imammedo@redhat.com> > > > --- > > > CC: Eduardo Habkost <ehabkost@redhat.com> > > > CC: Marcel Apfelbaum <marcel@redhat.com> > > > CC: Paolo Bonzini <pbonzini@redhat.com> > > > --- > > > include/hw/boards.h | 1 - > > > hw/core/null-machine.c | 10 +++++++--- > > > vl.c | 8 +++++++- > > > 3 files changed, 14 insertions(+), 5 deletions(-) > > > > > > diff --git a/include/hw/boards.h b/include/hw/boards.h > > > index 156b16f..decd0ec 100644 > > > --- a/include/hw/boards.h > > > +++ b/include/hw/boards.h > > > @@ -246,7 +246,6 @@ struct MachineState { > > > char *kernel_filename; > > > char *kernel_cmdline; > > > char *initrd_filename; > > > - const char *cpu_model; > > > const char *cpu_type; > > > AccelState *accelerator; > > > CPUArchIdList *possible_cpus; > > > diff --git a/hw/core/null-machine.c b/hw/core/null-machine.c > > > index 864832d..c2e466c 100644 > > > --- a/hw/core/null-machine.c > > > +++ b/hw/core/null-machine.c > > > @@ -23,10 +23,13 @@ > > > static void machine_none_init(MachineState *mch) > > > { > > > CPUState *cpu = NULL; > > > + MachineClass *mc = MACHINE_GET_CLASS(mch); > > > > > > - /* Initialize CPU (if a model has been specified) */ > > > - if (mch->cpu_model) { > > > - cpu = cpu_init(mch->cpu_model); > > > + /* Initialize CPU if cpu_type pointer is user provided > > > + * (i.e. != to pointer tot static default cpu type string) > > > + */ > > > + if (mch->cpu_type != mc->default_cpu_type) { > > > + cpu = cpu_create(mch->cpu_type); > > > > This is a big assumption about the code that sets mch->cpu_type. > > A simple g_strdup(machine_class->default_cpu_type) would break > > this silently (as it won't trigger the assert() below). > Yes, it's a bit of a hack to figure out is user has requested > cpu type explicitly. But so far there isn't need to do > g_strdup(machine_class->default_cpu_type) > when copying default in vl.c and guarding against it > looks like overkill currently. > > Cleaner way would be to make cpu_type property, add new property > API to set/check flags and use that here, there are other places > that would benefit from such API as well. > But it looks beyond scope of this series, so I used simple > hackish way to make it work with current code. > > I can amend comment here: > /* Initialize CPU if cpu_type pointer is user provided > * (i.e. != to pointer to static default cpu type string) > * MachineClass::default_cpu_type must be assigned to > * MachineState::cpu_type directly for this to work. > * TODO: > * - make cpu_type a property > * - add API to add/check user_set flag to property > * - use new API to check if property was user set > */ > > > > > > > > if (!cpu) { > > > error_report("Unable to initialize CPU"); > > > exit(1); > > > @@ -54,6 +57,7 @@ static void machine_none_machine_init(MachineClass *mc) > > > mc->init = machine_none_init; > > > mc->max_cpus = 1; > > > mc->default_ram_size = 0; > > > + mc->default_cpu_type = TARGET_DEFAULT_CPU_TYPE; > > > > Why do you need this? Isn't it simpler to just leave > > default_cpu_type=NULL here? > vl.c "-cpu" parsing depends on default_cpu_type being set > ... > if (machine_class->default_cpu_type) { > ... > } Right, this makes sense now. It looks like default_cpu_type is being overloaded for two different roles: 1) specifying the default CPU type; 2) finding the arch-specific class to be used to parse -cpu. In the case of null-machine, these two roles conflict with each other. I believe we can find other solutions instead of this hack that involves lying on MachineClass::default_cpu_type (and then having to work around the lie on machine_none_init()). I see multiple options: adding a new MachineClass field for that (e.g. resolving_cpu_type, which defaults to default_cpu_type if NULL); moving the CPU parsing code to arch_init.c (so it could use CPU_RESOLVING_TYPE or something similar); adding a optional MachineClass::parse_cpu_model hook. We could even try to get rid of CPUClass::parse_features completely > when we get rid of requirement for proxy type in > cpu_parse_cpu_model() > we can drop this ugliness in null-machine. I'd prefer to not introduce this ugliness in the first place. > > I'm doing it dirty way to prevent cpu_model resurgence > in boards code as it happened with nios2, even though > I've tried to monitor list for such patches. To be honest, I don't think the harm in having new code using MachineState::cpu_model is so big to justify this hack. > > > > } > > > > > > DEFINE_MACHINE("none", machine_none_machine_init) > > > diff --git a/vl.c b/vl.c > > > index 2586f25..8aa0131 100644 > > > --- a/vl.c > > > +++ b/vl.c > > > @@ -4609,7 +4609,6 @@ int main(int argc, char **argv, char **envp) > > > current_machine->maxram_size = maxram_size; > > > current_machine->ram_slots = ram_slots; > > > current_machine->boot_order = boot_order; > > > - current_machine->cpu_model = cpu_model; > > > > > > parse_numa_opts(current_machine); > > > > > > @@ -4619,6 +4618,13 @@ int main(int argc, char **argv, char **envp) > > > if (cpu_model) { > > > current_machine->cpu_type = > > > cpu_parse_cpu_model(machine_class->default_cpu_type, cpu_model); > > > + > > > + /* machine 'none' depends on default cpu type pointer not being > > > + * equal to resolved type name pointer to fugure out if type was > > > + * user provided, make sure that if it becomes not true in future > > > + * it won't beark silently */ > > > + g_assert( > > > + current_machine->cpu_type != machine_class->default_cpu_type); > > > } > > > } > > > > > > -- > > > 2.7.4 > > > > > >
On Thu, 18 Jan 2018 17:18:09 -0200 Eduardo Habkost <ehabkost@redhat.com> wrote: > On Thu, Jan 18, 2018 at 11:10:35AM +0100, Igor Mammedov wrote: > > On Wed, 17 Jan 2018 23:48:46 -0200 > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > On Wed, Jan 17, 2018 at 04:43:32PM +0100, Igor Mammedov wrote: > > > > The last user of it was machine type 'none', which used field > > > > to create CPU id user requested it on CLI with -cpu option. [...] > It looks like default_cpu_type is being overloaded for two > different roles: 1) specifying the default CPU type; 2) finding > the arch-specific class to be used to parse -cpu. > > In the case of null-machine, these two roles conflict with each > other. I believe we can find other solutions instead of this > hack that involves lying on MachineClass::default_cpu_type (and > then having to work around the lie on machine_none_init()). > > I see multiple options: adding a new MachineClass field for that > (e.g. resolving_cpu_type, which defaults to default_cpu_type if > NULL); moving the CPU parsing code to arch_init.c (so it could > use CPU_RESOLVING_TYPE or something similar); adding a optional > MachineClass::parse_cpu_model hook. We could even try to get rid > of CPUClass::parse_features completely Adding hooks just for the sake on null-machine seems to be overkill, I'd go for arch_init.c but it won't work for linux-user, how about exec.c as following: diff --git a/include/qom/cpu.h b/include/qom/cpu.h index 93bd546..0185589 100644 --- a/include/qom/cpu.h +++ b/include/qom/cpu.h @@ -661,8 +661,7 @@ ObjectClass *cpu_class_by_name(const char *typename, const char *cpu_model); [...] diff --git a/exec.c b/exec.c index d28fc0c..4543f06 100644 --- a/exec.c +++ b/exec.c @@ -817,6 +817,29 @@ void cpu_exec_realizefn(CPUState *cpu, Error **errp) #endif } +const char *parse_cpu_model(const char *cpu_model) +{ + ObjectClass *oc; + CPUClass *cc; + gchar **model_pieces; + const char *cpu_type; + + model_pieces = g_strsplit(cpu_model, ",", 2); + + oc = cpu_class_by_name(CPU_RESOLVING_TYPE, model_pieces[0]); + if (oc == NULL) { + error_report("unable to find CPU model '%s'", model_pieces[0]); + g_strfreev(model_pieces); + exit(EXIT_FAILURE); + } + + cpu_type = object_class_get_name(oc); + cc = CPU_CLASS(oc); + cc->parse_features(cpu_type, model_pieces[1], &error_fatal); + g_strfreev(model_pieces); + return cpu_type; +} + #if defined(CONFIG_USER_ONLY) static void breakpoint_invalidate(CPUState *cpu, target_ulong pc) { diff --git a/hw/core/null-machine.c b/hw/core/null-machine.c index 864832d..cde4d3e 100644 --- a/hw/core/null-machine.c +++ b/hw/core/null-machine.c @@ -24,9 +24,9 @@ static void machine_none_init(MachineState *mch) { CPUState *cpu = NULL; - /* Initialize CPU (if a model has been specified) */ - if (mch->cpu_model) { - cpu = cpu_init(mch->cpu_model); + /* Initialize CPU (if user asked for it) */ + if (mch->cpu_type) { + cpu = cpu_create(mch->cpu_type); if (!cpu) { error_report("Unable to initialize CPU"); exit(1); diff --git a/linux-user/main.c b/linux-user/main.c index a35477e..0afb3f4 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -4357,10 +4358,13 @@ int main(int argc, char **argv, char **envp) cpu_model = "any"; #endif } + cpu_type = parse_cpu_model(cpu_model); + tcg_exec_init(0); /* NOTE: we need to init the CPU at this stage to get qemu_host_page_size */ - cpu = cpu_init(cpu_model); + + cpu = cpu_create(cpu_type); env = cpu->env_ptr; cpu_reset(cpu); diff --git a/qom/cpu.c b/qom/cpu.c index e42d9a7..aab8437 100644 --- a/qom/cpu.c +++ b/qom/cpu.c @@ -67,37 +67,6 @@ CPUState *cpu_create(const char *typename) return cpu; } -const char *cpu_parse_cpu_model(const char *typename, const char *cpu_model) -{ [...] -} - -CPUState *cpu_generic_init(const char *typename, const char *cpu_model) -{ [...] -} - bool cpu_paging_enabled(const CPUState *cpu) { CPUClass *cc = CPU_GET_CLASS(cpu); diff --git a/vl.c b/vl.c index 2586f25..178bca3 100644 --- a/vl.c +++ b/vl.c @@ -4609,17 +4609,13 @@ int main(int argc, char **argv, char **envp) current_machine->maxram_size = maxram_size; current_machine->ram_slots = ram_slots; current_machine->boot_order = boot_order; - current_machine->cpu_model = cpu_model; parse_numa_opts(current_machine); /* parse features once if machine provides default cpu_type */ - if (machine_class->default_cpu_type) { - current_machine->cpu_type = machine_class->default_cpu_type; - if (cpu_model) { - current_machine->cpu_type = - cpu_parse_cpu_model(machine_class->default_cpu_type, cpu_model); - } + current_machine->cpu_type = machine_class->default_cpu_type; + if (cpu_model) { + current_machine->cpu_type = parse_cpu_model(cpu_model); } machine_run_board_init(current_machine);
On Fri, Jan 19, 2018 at 11:14:39AM +0100, Igor Mammedov wrote: > On Thu, 18 Jan 2018 17:18:09 -0200 > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > On Thu, Jan 18, 2018 at 11:10:35AM +0100, Igor Mammedov wrote: > > > On Wed, 17 Jan 2018 23:48:46 -0200 > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > On Wed, Jan 17, 2018 at 04:43:32PM +0100, Igor Mammedov wrote: > > > > > The last user of it was machine type 'none', which used field > > > > > to create CPU id user requested it on CLI with -cpu option. > [...] > > > It looks like default_cpu_type is being overloaded for two > > different roles: 1) specifying the default CPU type; 2) finding > > the arch-specific class to be used to parse -cpu. > > > > In the case of null-machine, these two roles conflict with each > > other. I believe we can find other solutions instead of this > > hack that involves lying on MachineClass::default_cpu_type (and > > then having to work around the lie on machine_none_init()). > > > > I see multiple options: adding a new MachineClass field for that > > (e.g. resolving_cpu_type, which defaults to default_cpu_type if > > NULL); moving the CPU parsing code to arch_init.c (so it could > > use CPU_RESOLVING_TYPE or something similar); adding a optional > > MachineClass::parse_cpu_model hook. We could even try to get rid > > of CPUClass::parse_features completely > Adding hooks just for the sake on null-machine seems to be overkill, > I'd go for arch_init.c but it won't work for linux-user, how about > exec.c as following: > > diff --git a/include/qom/cpu.h b/include/qom/cpu.h > index 93bd546..0185589 100644 > --- a/include/qom/cpu.h > +++ b/include/qom/cpu.h > @@ -661,8 +661,7 @@ ObjectClass *cpu_class_by_name(const char *typename, const char *cpu_model); > [...] > > diff --git a/exec.c b/exec.c > index d28fc0c..4543f06 100644 > --- a/exec.c > +++ b/exec.c > @@ -817,6 +817,29 @@ void cpu_exec_realizefn(CPUState *cpu, Error **errp) > #endif > } > > +const char *parse_cpu_model(const char *cpu_model) > +{ > + ObjectClass *oc; > + CPUClass *cc; > + gchar **model_pieces; > + const char *cpu_type; > + > + model_pieces = g_strsplit(cpu_model, ",", 2); > + > + oc = cpu_class_by_name(CPU_RESOLVING_TYPE, model_pieces[0]); > + if (oc == NULL) { > + error_report("unable to find CPU model '%s'", model_pieces[0]); > + g_strfreev(model_pieces); > + exit(EXIT_FAILURE); > + } > + > + cpu_type = object_class_get_name(oc); > + cc = CPU_CLASS(oc); > + cc->parse_features(cpu_type, model_pieces[1], &error_fatal); > + g_strfreev(model_pieces); > + return cpu_type; > +} Sounds good to me. Only two comments: This looks like duplication of cpu_parse_cpu_model(). Should this function body be replaced with: cpu_parse_cpu_model(CPU_RESOLVING_TYPE, cpu_model) ? I would move this to arch_init.c, because that's where existing target-dependent initialization code lives. > [...]
On Fri, 19 Jan 2018 11:14:30 -0200 Eduardo Habkost <ehabkost@redhat.com> wrote: > On Fri, Jan 19, 2018 at 11:14:39AM +0100, Igor Mammedov wrote: > > On Thu, 18 Jan 2018 17:18:09 -0200 > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > On Thu, Jan 18, 2018 at 11:10:35AM +0100, Igor Mammedov wrote: > > > > On Wed, 17 Jan 2018 23:48:46 -0200 > > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > > On Wed, Jan 17, 2018 at 04:43:32PM +0100, Igor Mammedov wrote: > > > > > > The last user of it was machine type 'none', which used field > > > > > > to create CPU id user requested it on CLI with -cpu option. > > [...] > > > > > It looks like default_cpu_type is being overloaded for two > > > different roles: 1) specifying the default CPU type; 2) finding > > > the arch-specific class to be used to parse -cpu. > > > > > > In the case of null-machine, these two roles conflict with each > > > other. I believe we can find other solutions instead of this > > > hack that involves lying on MachineClass::default_cpu_type (and > > > then having to work around the lie on machine_none_init()). > > > > > > I see multiple options: adding a new MachineClass field for that > > > (e.g. resolving_cpu_type, which defaults to default_cpu_type if > > > NULL); moving the CPU parsing code to arch_init.c (so it could > > > use CPU_RESOLVING_TYPE or something similar); adding a optional > > > MachineClass::parse_cpu_model hook. We could even try to get rid > > > of CPUClass::parse_features completely > > Adding hooks just for the sake on null-machine seems to be overkill, > > I'd go for arch_init.c but it won't work for linux-user, how about > > exec.c as following: > > > > diff --git a/include/qom/cpu.h b/include/qom/cpu.h > > index 93bd546..0185589 100644 > > --- a/include/qom/cpu.h > > +++ b/include/qom/cpu.h > > @@ -661,8 +661,7 @@ ObjectClass *cpu_class_by_name(const char *typename, const char *cpu_model); > > [...] > > > > diff --git a/exec.c b/exec.c > > index d28fc0c..4543f06 100644 > > --- a/exec.c > > +++ b/exec.c > > @@ -817,6 +817,29 @@ void cpu_exec_realizefn(CPUState *cpu, Error **errp) > > #endif > > } > > > > +const char *parse_cpu_model(const char *cpu_model) > > +{ > > + ObjectClass *oc; > > + CPUClass *cc; > > + gchar **model_pieces; > > + const char *cpu_type; > > + > > + model_pieces = g_strsplit(cpu_model, ",", 2); > > + > > + oc = cpu_class_by_name(CPU_RESOLVING_TYPE, model_pieces[0]); > > + if (oc == NULL) { > > + error_report("unable to find CPU model '%s'", model_pieces[0]); > > + g_strfreev(model_pieces); > > + exit(EXIT_FAILURE); > > + } > > + > > + cpu_type = object_class_get_name(oc); > > + cc = CPU_CLASS(oc); > > + cc->parse_features(cpu_type, model_pieces[1], &error_fatal); > > + g_strfreev(model_pieces); > > + return cpu_type; > > +} > > Sounds good to me. Only two comments: > > This looks like duplication of cpu_parse_cpu_model(). Should > this function body be replaced with: > cpu_parse_cpu_model(CPU_RESOLVING_TYPE, cpu_model) it's cpu_parse_cpu_model() which is moved to exec.c and first typename argument is replaced by inline CPU_RESOLVING_TYPE > I would move this to arch_init.c, because that's where existing > target-dependent initialization code lives. arch_init.c doesn't fit linux-user, it has only sys emulation code while exec.c is used by both and still target depended so CPU_RESOLVING_TYPE could be used there > > > > [...] >
On Fri, Jan 19, 2018 at 02:39:49PM +0100, Igor Mammedov wrote: > On Fri, 19 Jan 2018 11:14:30 -0200 > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > On Fri, Jan 19, 2018 at 11:14:39AM +0100, Igor Mammedov wrote: > > > On Thu, 18 Jan 2018 17:18:09 -0200 > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > On Thu, Jan 18, 2018 at 11:10:35AM +0100, Igor Mammedov wrote: > > > > > On Wed, 17 Jan 2018 23:48:46 -0200 > > > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > > > > > On Wed, Jan 17, 2018 at 04:43:32PM +0100, Igor Mammedov wrote: > > > > > > > The last user of it was machine type 'none', which used field > > > > > > > to create CPU id user requested it on CLI with -cpu option. > > > [...] > > > > > > > It looks like default_cpu_type is being overloaded for two > > > > different roles: 1) specifying the default CPU type; 2) finding > > > > the arch-specific class to be used to parse -cpu. > > > > > > > > In the case of null-machine, these two roles conflict with each > > > > other. I believe we can find other solutions instead of this > > > > hack that involves lying on MachineClass::default_cpu_type (and > > > > then having to work around the lie on machine_none_init()). > > > > > > > > I see multiple options: adding a new MachineClass field for that > > > > (e.g. resolving_cpu_type, which defaults to default_cpu_type if > > > > NULL); moving the CPU parsing code to arch_init.c (so it could > > > > use CPU_RESOLVING_TYPE or something similar); adding a optional > > > > MachineClass::parse_cpu_model hook. We could even try to get rid > > > > of CPUClass::parse_features completely > > > Adding hooks just for the sake on null-machine seems to be overkill, > > > I'd go for arch_init.c but it won't work for linux-user, how about > > > exec.c as following: > > > > > > diff --git a/include/qom/cpu.h b/include/qom/cpu.h > > > index 93bd546..0185589 100644 > > > --- a/include/qom/cpu.h > > > +++ b/include/qom/cpu.h > > > @@ -661,8 +661,7 @@ ObjectClass *cpu_class_by_name(const char *typename, const char *cpu_model); > > > [...] > > > > > > diff --git a/exec.c b/exec.c > > > index d28fc0c..4543f06 100644 > > > --- a/exec.c > > > +++ b/exec.c > > > @@ -817,6 +817,29 @@ void cpu_exec_realizefn(CPUState *cpu, Error **errp) > > > #endif > > > } > > > > > > +const char *parse_cpu_model(const char *cpu_model) > > > +{ > > > + ObjectClass *oc; > > > + CPUClass *cc; > > > + gchar **model_pieces; > > > + const char *cpu_type; > > > + > > > + model_pieces = g_strsplit(cpu_model, ",", 2); > > > + > > > + oc = cpu_class_by_name(CPU_RESOLVING_TYPE, model_pieces[0]); > > > + if (oc == NULL) { > > > + error_report("unable to find CPU model '%s'", model_pieces[0]); > > > + g_strfreev(model_pieces); > > > + exit(EXIT_FAILURE); > > > + } > > > + > > > + cpu_type = object_class_get_name(oc); > > > + cc = CPU_CLASS(oc); > > > + cc->parse_features(cpu_type, model_pieces[1], &error_fatal); > > > + g_strfreev(model_pieces); > > > + return cpu_type; > > > +} > > > > Sounds good to me. Only two comments: > > > > This looks like duplication of cpu_parse_cpu_model(). Should > > this function body be replaced with: > > cpu_parse_cpu_model(CPU_RESOLVING_TYPE, cpu_model) > it's cpu_parse_cpu_model() which is moved to exec.c > and first typename argument is replaced by inline CPU_RESOLVING_TYPE > > > > I would move this to arch_init.c, because that's where existing > > target-dependent initialization code lives. > arch_init.c doesn't fit linux-user, it has only sys emulation code > while exec.c is used by both and still target depended so CPU_RESOLVING_TYPE > could be used there I don't really like adding more code to the mess that is exec.c, but this looks like the simplest solution.
diff --git a/include/hw/boards.h b/include/hw/boards.h index 156b16f..decd0ec 100644 --- a/include/hw/boards.h +++ b/include/hw/boards.h @@ -246,7 +246,6 @@ struct MachineState { char *kernel_filename; char *kernel_cmdline; char *initrd_filename; - const char *cpu_model; const char *cpu_type; AccelState *accelerator; CPUArchIdList *possible_cpus; diff --git a/hw/core/null-machine.c b/hw/core/null-machine.c index 864832d..c2e466c 100644 --- a/hw/core/null-machine.c +++ b/hw/core/null-machine.c @@ -23,10 +23,13 @@ static void machine_none_init(MachineState *mch) { CPUState *cpu = NULL; + MachineClass *mc = MACHINE_GET_CLASS(mch); - /* Initialize CPU (if a model has been specified) */ - if (mch->cpu_model) { - cpu = cpu_init(mch->cpu_model); + /* Initialize CPU if cpu_type pointer is user provided + * (i.e. != to pointer tot static default cpu type string) + */ + if (mch->cpu_type != mc->default_cpu_type) { + cpu = cpu_create(mch->cpu_type); if (!cpu) { error_report("Unable to initialize CPU"); exit(1); @@ -54,6 +57,7 @@ static void machine_none_machine_init(MachineClass *mc) mc->init = machine_none_init; mc->max_cpus = 1; mc->default_ram_size = 0; + mc->default_cpu_type = TARGET_DEFAULT_CPU_TYPE; } DEFINE_MACHINE("none", machine_none_machine_init) diff --git a/vl.c b/vl.c index 2586f25..8aa0131 100644 --- a/vl.c +++ b/vl.c @@ -4609,7 +4609,6 @@ int main(int argc, char **argv, char **envp) current_machine->maxram_size = maxram_size; current_machine->ram_slots = ram_slots; current_machine->boot_order = boot_order; - current_machine->cpu_model = cpu_model; parse_numa_opts(current_machine); @@ -4619,6 +4618,13 @@ int main(int argc, char **argv, char **envp) if (cpu_model) { current_machine->cpu_type = cpu_parse_cpu_model(machine_class->default_cpu_type, cpu_model); + + /* machine 'none' depends on default cpu type pointer not being + * equal to resolved type name pointer to fugure out if type was + * user provided, make sure that if it becomes not true in future + * it won't beark silently */ + g_assert( + current_machine->cpu_type != machine_class->default_cpu_type); } }
The last user of it was machine type 'none', which used field to create CPU id user requested it on CLI with -cpu option. We could compare pointers of MachineState::cpu_type and MachineClass::default_cpu_type to check for the same condition, and drop cpu_model concept completly from machine/boards code So that no one would try to reuse obsolete field and only place to deal with cpu model would be vl.c and foo_cpu_class_by_name() callbacks. Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- CC: Eduardo Habkost <ehabkost@redhat.com> CC: Marcel Apfelbaum <marcel@redhat.com> CC: Paolo Bonzini <pbonzini@redhat.com> --- include/hw/boards.h | 1 - hw/core/null-machine.c | 10 +++++++--- vl.c | 8 +++++++- 3 files changed, 14 insertions(+), 5 deletions(-)