On Tue, Jul 12, 2016 at 11:13:00AM +0200, Christoph Hellwig wrote: > On Mon, Jul 11, 2016 at 12:43:41PM +0200, Alexander Gordeev wrote: > > > I diagreed - if we deprecated functions the only thing that should > > > be mentioned is a "don't use these". > > > > I will try to paraphrase myself. The new API deprecates pci_enable_msi*_range > > functions, but I am not that sure about others. Certainly, pci_msi*_vec__ount > > and pci_enable_msi*_exact could have (and AFAIR do have) uses that can not be > > covered by automatic initialization of pci_alloc_irq_vectors(). > > pci_enable_msi*_exact is the equivalent of pci_enable_msi*_range > with minvecs == maxvecs and treating any return value >= 0 as 0. Right. And people asked explicitly to introduce these helpers when range functions were introduced in the first place. Since there is handful of drivers that do use pci_enable_msi*_exact() I suppose a need for them persists. > I've updated the documentation so that the old usage examples are kept > around, but now use pci_alloc_irq_vectors. I've also added a more detaild > blurb on pci_msi*_vec_count - I think there is no need for them, but > if I'm proven wrong we'll have to add a pci_irq_vector_count that handles > all interrupt types later. I guess, it is up to Bjorn. But. Your proposed pci_nr_irq_vectors() function (a) is not a replacement for pci_msi*_vec_count() and (b) would be useless if I read its description properly: (a) Functions pci_msi*_vec_count() return number of vectors reported by a PCI device. It is a constant for the device and a driver may make an assumption based on this number; (b) A number returned by pci_nr_irq_vectors() is not guaranteed what a following call to pci_alloc_irq_vectors() can return (since the number of actually allocated vectors might change between the two calls). Therefore, a value returned by pci_nr_irq_vectors() can not be used for anything. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
