linux_dsm_epyc7002/drivers/net/ethernet/amd
Lendacky, Thomas 20a41fba67 amd-xgbe: Use wmb before updating current descriptor count
The code currently uses the lightweight dma_wmb barrier before updating
the current descriptor count. Under heavy load, the Tx cleanup routine
was seeing the updated current descriptor count before the updated
descriptor information. As a result, the Tx descriptor was being cleaned
up before it was used because it was not "owned" by the hardware yet,
resulting in a Tx queue hang.

Using the wmb barrier insures that the descriptor is updated before the
descriptor counter preventing the Tx queue hang. For extra insurance,
the Tx cleanup routine is changed to grab the current decriptor count on
entry and uses that initial value in the processing loop rather than
trying to chase the current value.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Tested-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-23 02:59:04 -07:00
..
xgbe amd-xgbe: Use wmb before updating current descriptor count 2015-10-23 02:59:04 -07:00
7990.c
7990.h
a2065.c
a2065.h
am79c961a.c
am79c961a.h
amd8111e.c ethernet: codespell comment spelling fixes 2015-03-08 22:54:22 -04:00
amd8111e.h ethernet: codespell comment spelling fixes 2015-03-08 22:54:22 -04:00
ariadne.c
ariadne.h
atarilance.c net: atarilance: Remove obsolete IRQ_TYPE_PRIO 2015-01-15 13:44:50 +01:00
au1000_eth.c net: ethernet: amd: drop owner assignment from platform_drivers 2014-10-20 16:21:04 +02:00
au1000_eth.h
declance.c declance: Fix 64-bit compilation warnings 2014-07-08 14:04:30 -07:00
hplance.c
hplance.h
Kconfig drivers/net: remove all references to obsolete Ethernet-HOWTO 2015-06-23 06:50:35 -07:00
lance.c
Makefile amd-xgbe: Configuration and build support 2014-06-05 15:26:51 -07:00
mvme147.c
ni65.c
ni65.h
nmclan_cs.c net: am2150: fix nmclan_cs.c shared interrupt handling 2015-01-29 15:08:21 -08:00
pcnet32.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-03-20 18:51:09 -04:00
sun3lance.c
sunlance.c net: ethernet: amd: drop owner assignment from platform_drivers 2014-10-20 16:21:04 +02:00