qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [PATCH 00/16] PCI device assignment: improve error repo


From: Laszlo Ersek
Subject: Re: [Qemu-devel] [PATCH 00/16] PCI device assignment: improve error reporting over QMP
Date: Wed, 30 Apr 2014 15:48:13 +0200
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0

Hi Luiz,

On 04/10/14 10:24, Laszlo Ersek wrote:
> This is for <https://bugzilla.redhat.com/show_bug.cgi?id=616415>.
> 
> In general, we want to propagate non-fatal (ie. non-exit()ing,
> non-abort()ing) errors to the QMP caller, rather than printing them
> on-site. The series focuses on errors raised at PCI assignment time (ie.
> reachable from assigned_initfn()), other errors are not converted.
> 
> Errors are not propagated through assigned_initfn(); let's wait for
> someone else to convert "kvm-pci-assign" from qdev to QOM. The series is
> nonetheless an improvement, because the forwarding of initialization
> errors now stops just before device_realize(). We set the
> stored/persistent monitor error there.
> 
> Informative and warning messages (that report about circumstances that
> don't break the assignment operation) cannot terminate in
> qerror_report_err(), because that would set the persistent monitor
> error, breaking the high level (QMP) operation.
> 
> A call graph rooted in assigned_initfn() was generated with cflow.
> Leaves that could never fail were removed from the graph (and this
> property similarly propagated upwards as far as possible).
> 
> The patchset loosely follows a bottom-up algorithm on this calltree. Any
> leaf that reports an error internally and returns a related failure is
> converted to "throw" an Error structure instead. All direct callers of
> the converted leaf are addressed at once, in the same patch, to consume
> the error (and they become the new leaves gradually).
> 
> When the leaf to be converted is also called outside of
> "hw/i386/kvm/pci-assign.c", the conversion keeps a compatibility
> function under the original name, so that conversion of callers
> unrelated to PCI assignment can be deferred.
> 
> Reviewers should copy the call graph to a text file, and mark, as the
> series progresses, fully converted functions. (Ie. functions that now
> report their terminating error messages with Error objects only.)
> 
>   assigned_initfn()
>       error_report()
>       get_real_device()
>           monitor_handle_fd_param()
>           error_report()
>           get_real_vendor_id()
>               get_real_id()
>                   error_report()
>           get_real_device_id()
>               get_real_id()
>                   error_report()
>       assigned_device_pci_cap_init()
>           check_irqchip_in_kernel()
>               error_report()
>           pci_add_capability()
>           error_report()
>       assigned_dev_register_msix_mmio()
>           error_report()
>       assigned_dev_register_regions()
>           error_report()
>       assign_device()
>           error_report()
>           assign_failed_examine()
>               get_real_vendor_id()
>                   get_real_id()
>                       error_report()
>               get_real_device_id()
>                   get_real_id()
>                       error_report()
>               error_printf()
>               error_report()
>       assign_intx()
>           check_irqchip_in_kernel()
>               error_report()
>           error_report()
>           error_printf()
> 
> Laszlo Ersek (16):
>   cutils: tighten qemu_parse_fd()
>   monitor: add Error-propagating monitor_handle_fd_param2()
>   pci-assign: accept Error from monitor_handle_fd_param2()
>   pci-assign: make assign_failed_examine() just format the cause
>   pci-assign: propagate errors from get_real_id()
>   pci-assign: propagate Error from check_irqchip_in_kernel()
>   pci: add Error-propagating pci_add_capability2()
>   pci-assign: accept Error from pci_add_capability2()
>   pci-assign: assignment should fail if we can't read config space
>   pci-assign: propagate errors from get_real_device()
>   pci-assign: propagate errors from assigned_device_pci_cap_init()
>   pci-assign: propagate errors from assigned_dev_register_msix_mmio()
>   pci-assign: propagate errors from assigned_dev_register_regions()
>   pci-assign: propagate errors from assign_device()
>   pci-assign: propagate errors from assign_intx()
>   pci-assign: assigned_initfn(): set monitor error in common error
>     handler
> 
>  include/hw/pci/pci.h      |   4 +
>  include/monitor/monitor.h |   1 +
>  hw/i386/kvm/pci-assign.c  | 273 
> ++++++++++++++++++++++++++++------------------
>  hw/pci/pci.c              |  32 +++++-
>  monitor.c                 |  29 ++++-
>  util/cutils.c             |  13 ++-
>  6 files changed, 232 insertions(+), 120 deletions(-)
> 

I forgot to CC you on this.

Thanks
Laszlo



reply via email to

[Prev in Thread] Current Thread [Next in Thread]