Re: [PATCH] bgmac: ratelimit warning messages

[Peter Senna Tschudin]

On Sat, Mar 7, 2015 at 12:27 AM, RafaÅ MiÅecki <zajec5@xxxxxxxxx> wrote:
> On 6 March 2015 at 19:17, Peter Senna Tschudin <peter.senna@xxxxxxxxx> wrote:
>> On my test environment the troughput of a file transfer drops from
>> 4.4Mbps to 116Kbps due the number of repeated warning messages.
>> Adding printk_ratelimit() solves the issue without removing the
>> warning message.
>>
>> Signed-off-by: Peter Senna Tschudin <peter.senna@xxxxxxxxx>
>> ---
>>  drivers/net/ethernet/broadcom/bgmac.c | 6 +++---
>>  1 file changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/broadcom/bgmac.c b/drivers/net/ethernet/broadcom/bgmac.c
>> index 676ffe0..d1a259b 100644
>> --- a/drivers/net/ethernet/broadcom/bgmac.c
>> +++ b/drivers/net/ethernet/broadcom/bgmac.c
>> @@ -302,7 +302,7 @@ static int bgmac_dma_rx_skb_for_slot(struct bgmac *bgmac,
>>         slot->skb = skb;
>>         slot->dma_addr = dma_addr;
>>
>> -       if (slot->dma_addr & 0xC0000000)
>> +       if ((slot->dma_addr & 0xC0000000) && printk_ratelimit())
>>                 bgmac_warn(bgmac, "DMA address using 0xC0000000 bit(s), it may need translation trick\n");
>>
>>         return 0;
>
> Nack. Please just drop this code.
>
> From what I understand network works for you. I've also checked
> Broadcom's open source code, and on SoC we can always safely write
> whole low 32b.

Yes, it works for me, even after:

-CONFIG_PAGE_OFFSET=0xC0000000
+CONFIG_PAGE_OFFSET=0x40000000
...
+CONFIG_VMSPLIT_1G=y
+# CONFIG_VMSPLIT_3G is not set

The page offset change was made by make menuconfig as a consequence of
CONFIG_VMSPLIT_1G. After the Kconfig changes the throughput is almost
40 times worst, but commenting the warnings fixes the issue. I'll send
V2 removing the messages completely.


-- 
Peter
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/