summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorIlias Apalodimas <ilias.apalodimas@linaro.org>2018-10-11 15:28:26 +0300
committerDavid S. Miller <davem@davemloft.net>2018-10-11 12:04:08 -0700
commit2a1e89df785082a0fd7264ca6d3d834abe84fa25 (patch)
treea3d7e659ba40da4b3aff973ece4e3b40c38262c6
parent26450608348e91a782691dbfcc836478f4381071 (diff)
net: socionext: clear rx irq correctly
commit 63ae7949e94a ("net: socionext: Use descriptor info instead of MMIO reads on Rx") removed constant mmio reads from the driver and started using a descriptor field to check if packet should be processed. This lead the napi rx handler being constantly called while no packets needed processing and ksoftirq getting 100% cpu usage. Issue one mmio read to clear the irq correcty after processing packets Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/net/ethernet/socionext/netsec.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/net/ethernet/socionext/netsec.c b/drivers/net/ethernet/socionext/netsec.c
index 7aa5ebb6766c..4289ccb26e4e 100644
--- a/drivers/net/ethernet/socionext/netsec.c
+++ b/drivers/net/ethernet/socionext/netsec.c
@@ -735,8 +735,11 @@ static int netsec_process_rx(struct netsec_priv *priv, int budget)
u16 idx = dring->tail;
struct netsec_de *de = dring->vaddr + (DESC_SZ * idx);
- if (de->attr & (1U << NETSEC_RX_PKT_OWN_FIELD))
+ if (de->attr & (1U << NETSEC_RX_PKT_OWN_FIELD)) {
+ /* reading the register clears the irq */
+ netsec_read(priv, NETSEC_REG_NRM_RX_PKTCNT);
break;
+ }
/* This barrier is needed to keep us from reading
* any other fields out of the netsec_de until we have