On Tue, Nov 19, 2019 at 02:38:23PM -0800, Rao Shoaib wrote:
>
> On 11/19/19 12:31 PM, Jason Gunthorpe wrote:
> > On Mon, Nov 18, 2019 at 11:54:38AM -0800, rao Shoaib wrote:
> > > From: Rao Shoaib <rao.shoaib@xxxxxxxxxx>
> > >
> > > Introduce maximum WQE size to impose limits on max SGE's and inline data
> > >
> > > Signed-off-by: Rao Shoaib <rao.shoaib@xxxxxxxxxx>
> > > drivers/infiniband/sw/rxe/rxe_param.h | 3 ++-
> > > drivers/infiniband/sw/rxe/rxe_qp.c | 7 +++++--
> > > 2 files changed, 7 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/drivers/infiniband/sw/rxe/rxe_param.h b/drivers/infiniband/sw/rxe/rxe_param.h
> > > index 1b596fb..31fb5c7 100644
> > > +++ b/drivers/infiniband/sw/rxe/rxe_param.h
> > > @@ -68,7 +68,6 @@ enum rxe_device_param {
> > > RXE_HW_VER = 0,
> > > RXE_MAX_QP = 0x10000,
> > > RXE_MAX_QP_WR = 0x4000,
> > > - RXE_MAX_INLINE_DATA = 400,
> > > RXE_DEVICE_CAP_FLAGS = IB_DEVICE_BAD_PKEY_CNTR
> > > | IB_DEVICE_BAD_QKEY_CNTR
> > > | IB_DEVICE_AUTO_PATH_MIG
> > > @@ -79,7 +78,9 @@ enum rxe_device_param {
> > > | IB_DEVICE_RC_RNR_NAK_GEN
> > > | IB_DEVICE_SRQ_RESIZE
> > > | IB_DEVICE_MEM_MGT_EXTENSIONS,
> > > + RXE_MAX_WQE_SIZE = 0x2d0, /* For RXE_MAX_SGE */
> > This shouldn't just be a random constant, I think you are trying to
> > say:
> >
> > RXE_MAX_WQE_SIZE = sizeof(struct rxe_send_wqe) + sizeof(struct ib_sge)*RXE_MAX_SGE
> I thought you wanted this value to be independent of RXE_MAX_SGE, else why
> are defining it.
Then define
RXE_MAX_SGE = (RXE_MAX_WQE_SIZE - sizeof(rxe_send_wqe))/sizeof(rxe_sge)
And drive everything off RXE_MAX_WQE_SIZE, which sounds good
> > Just say that
> >
> > > RXE_MAX_SGE = 32,
> > > + RXE_MAX_INLINE_DATA = RXE_MAX_WQE_SIZE,
> > This is mixed up now, it should be
> >
> > RXE_MAX_INLINE_DATA = RXE_MAX_WQE_SIZE - sizeof(rxe_send_wqe)
>
> I agree to what you are suggesting, it will make the current patch better.
> However, In my previous patch I had
>
> RXE_MAX_INLINE_DATA = RXE_MAX_SGE * sizeof(struct ib_sge)
>
> IMHO that conveys the intent much better. I do not see the reason for
> defining RXE_MAX_WQE_SIZE, ib_device_attr does not even have an entry for it
> and hence the value is not used anywhere by rxe or by any other relevant
> driver.
Because WQE_SIZE is what you are actually concerned with here, using
MAX_SGE as a proxy for the max WQE is confusing
Jason
