| Message ID | 20190815212821.120929-1-bvanassche@acm.org (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | PCI/P2PDMA: Fix a source code comment | expand |
On 2019-08-15 3:28 p.m., Bart Van Assche wrote: > Commit 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory"; v4.20) > introduced the following text: "there's no way to determine whether the > root complex supports forwarding between them." A later commit added a > whitelist check in the function that comment applies to. Update the > comment to reflect the addition of the whitelist check. Thanks for the vigilant patch, but I've already got a series[1] that cleans up most of these commits. It looks like this patch will conflict with that series. Logan [1] https://lore.kernel.org/linux-pci/20190812173048.9186-1-logang@deltatee.com/ > Cc: Logan Gunthorpe <logang@deltatee.com> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Keith Busch <keith.busch@intel.com> > Signed-off-by: Bart Van Assche <bvanassche@acm.org> > --- > drivers/pci/p2pdma.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c > index 234476226529..f719adc2b826 100644 > --- a/drivers/pci/p2pdma.c > +++ b/drivers/pci/p2pdma.c > @@ -300,8 +300,8 @@ static bool root_complex_whitelist(struct pci_dev *dev) > * Any two devices that don't have a common upstream bridge will return -1. > * In this way devices on separate PCIe root ports will be rejected, which > * is what we want for peer-to-peer seeing each PCIe root port defines a > - * separate hierarchy domain and there's no way to determine whether the root > - * complex supports forwarding between them. > + * separate hierarchy domain and there's no way other than using a whitelist > + * to determine whether the root complex supports forwarding between them. > * > * In the case where two devices are connected to different PCIe switches, > * this function will still return a positive distance as long as both >
On 8/15/19 2:32 PM, Logan Gunthorpe wrote: > On 2019-08-15 3:28 p.m., Bart Van Assche wrote: >> Commit 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory"; v4.20) >> introduced the following text: "there's no way to determine whether the >> root complex supports forwarding between them." A later commit added a >> whitelist check in the function that comment applies to. Update the >> comment to reflect the addition of the whitelist check. > > Thanks for the vigilant patch, but I've already got a series[1] that > cleans up most of these commits. It looks like this patch will conflict > with that series. Hi Logan, Thanks for the pointer. I'm fine with dropping this patch. Bart.
diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 234476226529..f719adc2b826 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -300,8 +300,8 @@ static bool root_complex_whitelist(struct pci_dev *dev) * Any two devices that don't have a common upstream bridge will return -1. * In this way devices on separate PCIe root ports will be rejected, which * is what we want for peer-to-peer seeing each PCIe root port defines a - * separate hierarchy domain and there's no way to determine whether the root - * complex supports forwarding between them. + * separate hierarchy domain and there's no way other than using a whitelist + * to determine whether the root complex supports forwarding between them. * * In the case where two devices are connected to different PCIe switches, * this function will still return a positive distance as long as both
Commit 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory"; v4.20) introduced the following text: "there's no way to determine whether the root complex supports forwarding between them." A later commit added a whitelist check in the function that comment applies to. Update the comment to reflect the addition of the whitelist check. Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Keith Busch <keith.busch@intel.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- drivers/pci/p2pdma.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)