On Fri, Jun 09, 2023 at 06:59:57PM +0200, Jan Klemkow wrote:
> On Fri, Jun 09, 2023 at 06:11:38PM +0200, Jan Klemkow wrote:
> > TSO packets are limited to MAXMCLBYTES (64k). Thus, we don't need to
> > allocate IXGBE_TSO_SIZE (256k) per packet for the transmit buffers.
> >
> > This saves 3/4 of the memory and allows me to pack over 8 ix(8) ports
> > into one machine. Otherwise I run out of devbuf in malloc(9).
>
> fix typo in comment
Use a more precise compare in the CTASSERT condition.
ok?
Index: dev/pci/if_ix.c
===================================================================
RCS file: /cvs/src/sys/dev/pci/if_ix.c,v
retrieving revision 1.197
diff -u -p -r1.197 if_ix.c
--- dev/pci/if_ix.c 1 Jun 2023 09:05:33 -0000 1.197
+++ dev/pci/if_ix.c 9 Jun 2023 16:01:18 -0000
@@ -37,6 +37,12 @@
#include <dev/pci/if_ix.h>
#include <dev/pci/ixgbe_type.h>
+/*
+ * Our TCP/IP Stack could not handle packets greater than MAXMCLBYTES.
+ * This interface could not handle packets greater than IXGBE_TSO_SIZE.
+ */
+CTASSERT(MAXMCLBYTES <= IXGBE_TSO_SIZE);
+
/*********************************************************************
* Driver version
*********************************************************************/
@@ -2263,7 +2269,7 @@ ixgbe_allocate_transmit_buffers(struct t
/* Create the descriptor buffer dma maps */
for (i = 0; i < sc->num_tx_desc; i++) {
txbuf = &txr->tx_buffers[i];
- error = bus_dmamap_create(txr->txdma.dma_tag, IXGBE_TSO_SIZE,
+ error = bus_dmamap_create(txr->txdma.dma_tag, MAXMCLBYTES,
sc->num_segs, PAGE_SIZE, 0,
BUS_DMA_NOWAIT, &txbuf->map);
