From mboxrd@z Thu Jan 1 00:00:00 1970 From: Don Slutz Subject: Re: [PATCH v3 2/4] GlobalProperty: Display warning about unused -global Date: Tue, 22 Apr 2014 16:23:59 -0400 Message-ID: <5356CFDF.7000303@terremark.com> References: <1395705336-22528-1-git-send-email-dslutz@verizon.com> <1395705336-22528-3-git-send-email-dslutz@verizon.com> <53514312.5060705@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <53514312.5060705@suse.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org To: =?ISO-8859-15?Q?Andreas_F=E4rber?= , Don Slutz Cc: xen-devel@lists.xensource.com, "Michael S. Tsirkin" , qemu-devel@nongnu.org, Anthony Liguori , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On 04/18/14 11:21, Andreas Färber wrote: > Hi Don, > > Am 25.03.2014 00:55, schrieb Don Slutz: >> This can help a user understand why -global was ignored. >> >> For example: with "-vga cirrus"; "-global vga.vgamem_mb=16" is just >> ignored when "-global cirrus-vga.vgamem_mb=16" is not. >> >> This is currently clear when the wrong property is provided: >> >> out/x86_64-softmmu/qemu-system-x86_64 -global cirrus-vga.vram_size_mb=16 -monitor pty -vga cirrus >> char device redirected to /dev/pts/20 (label compat_monitor0) >> qemu-system-x86_64: Property '.vram_size_mb' not found >> Aborted (core dumped) >> >> vs >> >> out/x86_64-softmmu/qemu-system-x86_64 -global vga.vram_size_mb=16 -monitor pty -vga cirrus >> char device redirected to /dev/pts/20 (label compat_monitor0) >> VNC server running on `::1:5900' >> ^Cqemu: terminating on signal 2 >> >> Signed-off-by: Don Slutz > Improving this is greatly appreciated, thanks. > > Now, I can see two ways things can go wrong: a) Mistyping or later > refactoring devices, or b) user typos or thinkos. > And four ways to set globals: -global, config file (I hope?), legacy > command line options (vl.c) and machine .compat_props. > > If a property does not exist on the instance of an existing type, > object_property_parse() will raise an Error and we will abort in > device_post_init(). > > What we are silently missing is if a type is misspelled; for that we can > probably add an Error **errp to the two qdev_prop_register_global*() > functions - assuming QOM types are already registered at that point. > qom-test would help us catch any such mistake by instantiating each machine. I assume you are talking about qdev_prop_register_global() and qdev_prop_register_global_list(). In my testing I did not see QOM types being registered at that point. I may have not been looking at the right thing. What I am sure on is that the new object pc-memory-layout (added in 2/4) is not there just like TYPE_ICC_BRIDGE at the calls to qdev_prop_register_global*(). Currently I have issues running tests: dcs-xen-50:~/qemu/out>make test make -C tests/tcg test make[1]: Entering directory `/home/don/qemu/out/tests/tcg' cc -m32 -I/home/don/qemu/tcg -I/home/don/qemu/tcg/i386 -I/home/don/qemu/linux-headers -I/home/don/qemu/out/linux-headers -I. -I/home/don/qemu -I/home/don/qemu/include -I/home/don/qemu/libcacard -I/home/don/qemu/tests/tcg -I. -I../.. -pthread -I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include -Wall -O2 -g -fno-strict-aliasing -c -o test_path.o /home/don/qemu/tests/tcg/test_path.c In file included from /home/don/qemu/util/cutils.c:25:0, from /home/don/qemu/tests/tcg/test_path.c:4: /home/don/qemu/include/qemu/host-utils.h: In function 'mulu64': /home/don/qemu/include/qemu/host-utils.h:35:5: error: unknown type name '__uint128_t' /home/don/qemu/include/qemu/host-utils.h:35:22: error: '__uint128_t' undeclared (first use in this function) /home/don/qemu/include/qemu/host-utils.h:35:22: note: each undeclared identifier is reported only once for each function it appears in ... > > I note that your proposed check is not failing, but still, with hot-add > of e.g. PCI devices we might well get a global property default for a > type that is not instantiated immediately but possibly used later on. This looks correct to me. I do not know enough in the area, but at a quick look, type_register_static() could look at .hotpluggable and .props. and maybe do some checking. >> --- >> hw/core/qdev-properties-system.c | 1 + >> hw/core/qdev-properties.c | 15 +++++++++++++++ >> include/hw/qdev-core.h | 1 + >> include/hw/qdev-properties.h | 1 + >> vl.c | 2 ++ >> 5 files changed, 20 insertions(+) > FWIW I'd prefer "qdev:" for consistency (and yes, it's ambiguous), since > there are no "GlobalProperty" files or directory. > Ok, Will change. >> diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c >> index de83561..9c742ca 100644 >> --- a/hw/core/qdev-properties-system.c >> +++ b/hw/core/qdev-properties-system.c >> @@ -444,6 +444,7 @@ static int qdev_add_one_global(QemuOpts *opts, void *opaque) >> g->driver = qemu_opt_get(opts, "driver"); >> g->property = qemu_opt_get(opts, "property"); >> g->value = qemu_opt_get(opts, "value"); >> + g->not_used = true; >> qdev_prop_register_global(g); >> return 0; >> } > IIUC your patch relies on not_used being false in the non-QemuOpts case > to avoid noise when using -nodefaults or pc*-x.y. Still, the C99 struct > initializations elsewhere get that field as well, hmm. An alternative > would be a separate linked list for user-supplied globals. > Yes, a separate linked list could be used. Did not look at doing this. Mostly since struct init will always set not_used to false. >> diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c >> index c67acf5..437c008 100644 >> --- a/hw/core/qdev-properties.c >> +++ b/hw/core/qdev-properties.c >> @@ -951,6 +951,20 @@ void qdev_prop_register_global_list(GlobalProperty *props) >> } >> } >> >> +void qdev_prop_check_global(void) >> +{ >> + GlobalProperty *prop; >> + >> + QTAILQ_FOREACH(prop, &global_props, next) { >> + if (!prop->not_used) { >> + continue; >> + } >> + fprintf(stderr, "Warning: \"-global %s.%s=%s\" not used\n", >> + prop->driver, prop->property, prop->value); >> + >> + } >> +} >> + >> void qdev_prop_set_globals_for_type(DeviceState *dev, const char *typename, >> Error **errp) >> { >> @@ -962,6 +976,7 @@ void qdev_prop_set_globals_for_type(DeviceState *dev, const char *typename, >> if (strcmp(typename, prop->driver) != 0) { >> continue; >> } >> + prop->not_used = false; >> object_property_parse(OBJECT(dev), prop->value, prop->property, &err); >> if (err != NULL) { >> error_propagate(errp, err); >> diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h >> index dbe473c..131fb49 100644 >> --- a/include/hw/qdev-core.h >> +++ b/include/hw/qdev-core.h >> @@ -235,6 +235,7 @@ typedef struct GlobalProperty { >> const char *driver; >> const char *property; >> const char *value; >> + bool not_used; >> QTAILQ_ENTRY(GlobalProperty) next; >> } GlobalProperty; >> >> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h >> index c46e908..fbca313 100644 >> --- a/include/hw/qdev-properties.h >> +++ b/include/hw/qdev-properties.h >> @@ -180,6 +180,7 @@ void qdev_prop_set_ptr(DeviceState *dev, const char *name, void *value); >> >> void qdev_prop_register_global(GlobalProperty *prop); >> void qdev_prop_register_global_list(GlobalProperty *props); >> +void qdev_prop_check_global(void); >> void qdev_prop_set_globals(DeviceState *dev, Error **errp); >> void qdev_prop_set_globals_for_type(DeviceState *dev, const char *typename, >> Error **errp); >> diff --git a/vl.c b/vl.c >> index acd97a8..61fac1b 100644 >> --- a/vl.c >> +++ b/vl.c >> @@ -4490,6 +4490,8 @@ int main(int argc, char **argv, char **envp) >> } >> } >> >> + qdev_prop_check_global(); > I have some doubts about this placement. A machine init done notifier > might avoid touching vl.c by leaving it in qdev-properties.c. It happens > to be after that point as is, but later refactorings wrt QOM realize or > unrelated issues might change that. Yes, This was the best place I found for it. I am happy to move if that makes sense. -Don Slutz >> + >> if (incoming) { >> Error *local_err = NULL; >> qemu_start_incoming_migration(incoming, &local_err); > Regards, > Andreas >