Re: [PATCH v7 01/11] qapi/error: add (Error **errp) cleaning APIs

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

21.02.2020 10:38, Markus Armbruster wrote:
> Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> writes:
> 
>> Add functions to clean Error **errp: call corresponding Error *err
>> cleaning function an set pointer to NULL.
>>
>> New functions:
>>    error_free_errp
>>    error_report_errp
>>    warn_report_errp
>>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
>> Reviewed-by: Greg Kurz <groug@kaod.org>
>> Reviewed-by: Eric Blake <eblake@redhat.com>
>> ---
>>
>> CC: Eric Blake <eblake@redhat.com>
>> CC: Kevin Wolf <kwolf@redhat.com>
>> CC: Max Reitz <mreitz@redhat.com>
>> CC: Greg Kurz <groug@kaod.org>
>> CC: Stefano Stabellini <sstabellini@kernel.org>
>> CC: Anthony Perard <anthony.perard@citrix.com>
>> CC: Paul Durrant <paul@xen.org>
>> CC: Stefan Hajnoczi <stefanha@redhat.com>
>> CC: "Philippe Mathieu-Daudé" <philmd@redhat.com>
>> CC: Laszlo Ersek <lersek@redhat.com>
>> CC: Gerd Hoffmann <kraxel@redhat.com>
>> CC: Stefan Berger <stefanb@linux.ibm.com>
>> CC: Markus Armbruster <armbru@redhat.com>
>> CC: Michael Roth <mdroth@linux.vnet.ibm.com>
>> CC: qemu-block@nongnu.org
>> CC: xen-devel@lists.xenproject.org
>>
>>   include/qapi/error.h | 26 ++++++++++++++++++++++++++
>>   1 file changed, 26 insertions(+)
>>
>> diff --git a/include/qapi/error.h b/include/qapi/error.h
>> index ad5b6e896d..d34987148d 100644
>> --- a/include/qapi/error.h
>> +++ b/include/qapi/error.h
>> @@ -309,6 +309,32 @@ void warn_reportf_err(Error *err, const char *fmt, ...)
>>   void error_reportf_err(Error *err, const char *fmt, ...)
>>       GCC_FMT_ATTR(2, 3);
>>   
>> +/*
>> + * Functions to clean Error **errp: call corresponding Error *err cleaning
>> + * function, then set pointer to NULL.
>> + */
>> +static inline void error_free_errp(Error **errp)
>> +{
>> +    assert(errp && *errp);
>> +    error_free(*errp);
>> +    *errp = NULL;
>> +}
>> +
>> +static inline void error_report_errp(Error **errp)
>> +{
>> +    assert(errp && *errp);
>> +    error_report_err(*errp);
>> +    *errp = NULL;
>> +}
>> +
>> +static inline void warn_report_errp(Error **errp)
>> +{
>> +    assert(errp && *errp);
>> +    warn_report_err(*errp);
>> +    *errp = NULL;
>> +}
>> +
>> +
>>   /*
>>    * Just like error_setg(), except you get to specify the error class.
>>    * Note: use of error classes other than ERROR_CLASS_GENERIC_ERROR is
> 
> These appear to be unused apart from the Coccinelle script in PATCH 03.
> 
> They are used in the full "[RFC v5 000/126] error: auto propagated
> local_err" series.  Options:
> 
> 1. Pick a few more patches into this part I series, so these guys come
>     with users.

It needs some additional effort for this series.. But it's possible. Still,
I think that we at least should not pull out patches which should be in
future series (for example from ppc or block/)..

Grepping through v5:
  for x in {warn_report_errp,error_report_errp,error_free_errp}; do echo == $x ==; git grep -l $x | grep -v coccinelle | grep -v 'error\.h'; echo; done
== warn_report_errp ==
block/file-posix.c
hw/ppc/spapr.c
hw/ppc/spapr_caps.c
hw/ppc/spapr_irq.c
hw/vfio/pci.c
net/tap.c
qom/object.c

== error_report_errp ==
hw/block/vhost-user-blk.c
util/oslib-posix.c

== error_free_errp ==
block.c
block/qapi.c
block/sheepdog.c
block/snapshot.c
blockdev.c
chardev/char-socket.c
hw/audio/intel-hda.c
hw/core/qdev-properties.c
hw/pci-bridge/pci_bridge_dev.c
hw/pci-bridge/pcie_pci_bridge.c
hw/scsi/megasas.c
hw/scsi/mptsas.c
hw/usb/hcd-xhci.c
io/net-listener.c
migration/colo.c
qga/commands-posix.c
qga/commands-win32.c
util/qemu-sockets.c

What do you want to add?

> 
> 2. Punt this patch to the first part that has users, along with the
>     part of the Coccinelle script that deals with them.

But coccinelle script would be wrong, if we drop this part from it. I think,
that after commit which adds coccinelle script, it should work with any file,
not only subset of these series.

So, it's probably OK for now to drop these functions, forcing their addition if
coccinelle script will be applied where these functions are needed. We can, for
example comment these three functions.

Splitting coccinelle script into two parts, which will be in different series will
not help any patch-porting processes.

Moreover, this will create dependencies between future series updating other files.

So, I don't like [2.]..

> 
> 3. Do nothing: accept the functions without users.

OK for me)

> 
> I habitually dislike 3., but reviewing the rest of this series might
> make me override that dislike.
> 

----------------

same grep with maintainers:
  for x in {warn_report_errp,error_report_errp,error_free_errp}; do echo == $x ==; git grep -l $x | grep -v coccinelle | grep -v 'error\.h' | while read f; do echo $f; ./scripts/get_maintainer.pl -f --no-rolestats $f | grep -v 'qemu-block\|qemu-devel' | sed -e 's/^/   /'; done; echo; done
== warn_report_errp ==
block/file-posix.c
    Kevin Wolf <kwolf@redhat.com>
    Max Reitz <mreitz@redhat.com>
hw/ppc/spapr.c
    David Gibson <david@gibson.dropbear.id.au>
    qemu-ppc@nongnu.org
hw/ppc/spapr_caps.c
    David Gibson <david@gibson.dropbear.id.au>
    qemu-ppc@nongnu.org
hw/ppc/spapr_irq.c
    David Gibson <david@gibson.dropbear.id.au>
    qemu-ppc@nongnu.org
hw/vfio/pci.c
    Alex Williamson <alex.williamson@redhat.com>
net/tap.c
    Jason Wang <jasowang@redhat.com>
qom/object.c
    Paolo Bonzini <pbonzini@redhat.com>
    "Daniel P. Berrangé" <berrange@redhat.com>
    Eduardo Habkost <ehabkost@redhat.com>

== error_report_errp ==
hw/block/vhost-user-blk.c
    "Michael S. Tsirkin" <mst@redhat.com>
    Kevin Wolf <kwolf@redhat.com>
    Max Reitz <mreitz@redhat.com>
util/oslib-posix.c
    Paolo Bonzini <pbonzini@redhat.com>

== error_free_errp ==
block.c
    Kevin Wolf <kwolf@redhat.com>
    Max Reitz <mreitz@redhat.com>
block/qapi.c
    Markus Armbruster <armbru@redhat.com>
    Kevin Wolf <kwolf@redhat.com>
    Max Reitz <mreitz@redhat.com>
block/sheepdog.c
    Liu Yuan <namei.unix@gmail.com>
    Kevin Wolf <kwolf@redhat.com>
    Max Reitz <mreitz@redhat.com>
    sheepdog@lists.wpkg.org
block/snapshot.c
    Kevin Wolf <kwolf@redhat.com>
    Max Reitz <mreitz@redhat.com>
blockdev.c
    Markus Armbruster <armbru@redhat.com>
    Kevin Wolf <kwolf@redhat.com>
    Max Reitz <mreitz@redhat.com>
chardev/char-socket.c
    "Marc-André Lureau" <marcandre.lureau@redhat.com>
    Paolo Bonzini <pbonzini@redhat.com>
hw/audio/intel-hda.c
    Gerd Hoffmann <kraxel@redhat.com>
hw/core/qdev-properties.c
    Paolo Bonzini <pbonzini@redhat.com>
    "Daniel P. Berrangé" <berrange@redhat.com>
    Eduardo Habkost <ehabkost@redhat.com>
hw/pci-bridge/pci_bridge_dev.c
    "Michael S. Tsirkin" <mst@redhat.com>
    Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
hw/pci-bridge/pcie_pci_bridge.c
    "Michael S. Tsirkin" <mst@redhat.com>
    Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
hw/scsi/megasas.c
    Hannes Reinecke <hare@suse.com>
    Paolo Bonzini <pbonzini@redhat.com>
    Fam Zheng <fam@euphon.net>
hw/scsi/mptsas.c
    Paolo Bonzini <pbonzini@redhat.com>
    Fam Zheng <fam@euphon.net>
hw/usb/hcd-xhci.c
    Gerd Hoffmann <kraxel@redhat.com>
io/net-listener.c
    "Daniel P. Berrangé" <berrange@redhat.com>
migration/colo.c
    Hailiang Zhang <zhang.zhanghailiang@huawei.com>
    Juan Quintela <quintela@redhat.com>
    "Dr. David Alan Gilbert" <dgilbert@redhat.com>
qga/commands-posix.c
    Michael Roth <mdroth@linux.vnet.ibm.com>
qga/commands-win32.c
    Michael Roth <mdroth@linux.vnet.ibm.com>
util/qemu-sockets.c
    "Daniel P. Berrangé" <berrange@redhat.com>
    Gerd Hoffmann <kraxel@redhat.com>



-- 
Best regards,
Vladimir