evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

be2net: fix erx->rx_drops_no_frags wrap around

Browse source 
The rx_drops_no_frags HW counter for RSS rings is 16bits in HW and can
wraparound often. Maintain a 32-bit accumulator in the driver to prevent
frequent wraparound.

Also, incorporated Eric's feedback to use ACCESS_ONCE() for the accumulator
write.

Signed-off-by: Sathya Perla <sathya.perla@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sathya Perla 2011-08-22 19:41:53 +00:00 • committed by David S. Miller
parent db3ea7819d
commit 09c1c68f22
1 changed files with 19 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

22
drivers/net/ethernet/emulex/benet/be_main.c
View file

@ -378,6 +378,18 @@ static void populate_lancer_stats(struct be_adapter *adapter)
pport_stats->rx_drops_too_many_frags_lo; pport_stats->rx_drops_too_many_frags_lo;
} }
static void accumulate_16bit_val(u32 *acc, u16 val)
{
#define lo(x) (x & 0xFFFF)
#define hi(x) (x & 0xFFFF0000)
bool wrapped = val < lo(*acc);
u32 newacc = hi(*acc) + val;
if (wrapped)
newacc += 65536;
ACCESS_ONCE(*acc) = newacc;
}
void be_parse_stats(struct be_adapter *adapter) void be_parse_stats(struct be_adapter *adapter)
{ {
struct be_erx_stats_v1 *erx = be_erx_stats_from_cmd(adapter); struct be_erx_stats_v1 *erx = be_erx_stats_from_cmd(adapter);
@ -394,9 +406,13 @@ void be_parse_stats(struct be_adapter *adapter)
} }
/* as erx_v1 is longer than v0, ok to use v1 defn for v0 access */ /* as erx_v1 is longer than v0, ok to use v1 defn for v0 access */
for_all_rx_queues(adapter, rxo, i) for_all_rx_queues(adapter, rxo, i) {
rx_stats(rxo)->rx_drops_no_frags = /* below erx HW counter can actually wrap around after
erx->rx_drops_no_fragments[rxo->q.id]; * 65535. Driver accumulates a 32-bit value
*/
accumulate_16bit_val(&rx_stats(rxo)->rx_drops_no_frags,
(u16)erx->rx_drops_no_fragments[rxo->q.id]);
}
} }
static struct rtnl_link_stats64 *be_get_stats64(struct net_device *netdev, static struct rtnl_link_stats64 *be_get_stats64(struct net_device *netdev,