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I'm not an expert on that corner of > the PCI core. > > But indeed what you could try is amend that function to not only > *set* PCI_EXP_DEVCTL2_ATOMIC_REQ if it's supported, but to also > *clear* it if it's not supported. > > And you'd have to call pci_enable_atomic_ops_to_root() on enumeration, > e.g. from pci_init_capabilities(). > > That should obviate the need to call pci_enable_atomic_ops_to_root() > from drivers, so you could probably remove the call from all the > drivers which currently call it (amdgpu, infiniband, mellanox), > in one separate patch per driver. > > An then you could drop the EXPORT clause for pci_enable_atomic_ops_to_root() > and make it private to the PCI core. > > So that would be 5 patches (enablement/disablement on enumeration, > amendmend of the 3 drivers, making the call private). > > I'm not sure if anyone will cry foul if you do that but if you want > to give it a try, go for it. :) Okay, I see there are no objections except for Bjorn/Jay's comments on "But there could be devices where AtomicOps are nominally supported but untested or broken.." Would this be an issue? If not, I will start working on those 5 patches. Thanks, Smita > > I don't now why commit 430a23689dea, which introduced > pci_enable_atomic_ops_to_root(), chose to add it as a library function > which is only called from specific drivers, instead of universally > enabling the feature for all devices. Adding the commit authors to cc > so they can chime in. > > Thanks, > > Lukas