UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

staging/rdma/hfi1: Prevent host software lock up 

If packets stop egressing the hardware link, software can lock up.

Implement a timeout for send context halt recovery.  This patch increases the
timeout for packet egress to 500 us and timer resets to zero if the packet
occupancy changes. Also we bounce the link on time out.

Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Vennila Megavannan <vennila.megavannan@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Vennila Megavannan 2015-10-26 10:28:30 -04:00 committed by Greg Kroah-Hartman
parent dc060245a2
commit 25d97dd5a3
2 changed files with 23 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/staging/rdma/hfi1/pio.c
View File

@ -922,10 +922,12 @@ void sc_disable(struct send_context *sc)
static void sc_wait_for_packet_egress(struct send_context *sc, int pause) static void sc_wait_for_packet_egress(struct send_context *sc, int pause)
{ {
struct hfi1_devdata *dd = sc->dd; struct hfi1_devdata *dd = sc->dd;
u64 reg; u64 reg = 0;
u64 reg_prev;
u32 loop = 0; u32 loop = 0;
while (1) { while (1) {
reg_prev = reg;
reg = read_csr(dd, sc->hw_context * 8 + reg = read_csr(dd, sc->hw_context * 8 +
SEND_EGRESS_CTXT_STATUS); SEND_EGRESS_CTXT_STATUS);
/* done if egress is stopped */ /* done if egress is stopped */
@ -934,11 +936,17 @@ static void sc_wait_for_packet_egress(struct send_context *sc, int pause)
reg = packet_occupancy(reg); reg = packet_occupancy(reg);
if (reg == 0) if (reg == 0)
break; break;
if (loop > 100) { /* counter is reset if occupancy count changes */
if (reg != reg_prev)
loop = 0;
if (loop > 500) {
/* timed out - bounce the link */
dd_dev_err(dd, dd_dev_err(dd,
"%s: context %u(%u) timeout waiting for packets to egress, remaining count %u\n", "%s: context %u(%u) timeout waiting for packets to egress, remaining count %u, bouncing link\n",
__func__, sc->sw_index, __func__, sc->sw_index,
sc->hw_context, (u32)reg); sc->hw_context, (u32)reg);
queue_work(dd->pport->hfi1_wq,
&dd->pport->link_bounce_work);
break; break;
} }
loop++; loop++;

15
drivers/staging/rdma/hfi1/sdma.c
View File

@ -303,17 +303,26 @@ static void sdma_wait_for_packet_egress(struct sdma_engine *sde,
u64 off = 8 * sde->this_idx; u64 off = 8 * sde->this_idx;
struct hfi1_devdata *dd = sde->dd; struct hfi1_devdata *dd = sde->dd;
int lcnt = 0; int lcnt = 0;
u64 reg_prev;
u64 reg = 0;
while (1) { while (1) {
u64 reg = read_csr(dd, off + SEND_EGRESS_SEND_DMA_STATUS); reg_prev = reg;
reg = read_csr(dd, off + SEND_EGRESS_SEND_DMA_STATUS);
reg &= SDMA_EGRESS_PACKET_OCCUPANCY_SMASK; reg &= SDMA_EGRESS_PACKET_OCCUPANCY_SMASK;
reg >>= SDMA_EGRESS_PACKET_OCCUPANCY_SHIFT; reg >>= SDMA_EGRESS_PACKET_OCCUPANCY_SHIFT;
if (reg == 0) if (reg == 0)
break; break;
if (lcnt++ > 100) { /* counter is reest if accupancy count changes */
dd_dev_err(dd, "%s: engine %u timeout waiting for packets to egress, remaining count %u\n", if (reg != reg_prev)
lcnt = 0;
if (lcnt++ > 500) {
/* timed out - bounce the link */
dd_dev_err(dd, "%s: engine %u timeout waiting for packets to egress, remaining count %u, bouncing link\n",
__func__, sde->this_idx, (u32)reg); __func__, sde->this_idx, (u32)reg);
queue_work(dd->pport->hfi1_wq,
&dd->pport->link_bounce_work);
break; break;
} }
udelay(1); udelay(1);