On Wed, Mar 17, 2021 at 03:08:09PM +0530, Kanchan Joshi wrote: > On Tue, Mar 16, 2021 at 10:53 PM Keith Busch <kbusch@xxxxxxxxxx> wrote: > > > > On Tue, Mar 16, 2021 at 07:31:25PM +0530, Kanchan Joshi wrote: > > > nvme_req structure originally contained a pointer to nvme_command. > > > Change nvme_req structure to keep the command itself. > > > This helps in avoiding hot-path memory-allocation for async-passthrough. > > > > I have a slightly different take on how to handle pre-allocated > > passthrough commands. Every transport except PCI already preallocates a > > 'struct nvme_command' within the pdu, so allocating another one looks > > redundant. Also, it does consume quite a bit of memory for something > > that is used only for the passthrough case. > > > > I think we can solve both concerns by always using the PDU nvme_command > > rather than have the transport drivers provide it. I just sent the patch > > here if you can take a look. It tested fine on PCI and loop (haven't > > tested any other transports). > > > > http://lists.infradead.org/pipermail/linux-nvme/2021-March/023711.html > > Sounds fine, thanks for the patch, looking at it. > Which kernel you used for these. 'Patch 2' doesn't apply cleanly. I used nvme-5.13 as my starting point. http://git.infradead.org/nvme.git/shortlog/refs/heads/nvme-5.13
