diff options
| author | Ben Hutchings <bhutchings@solarflare.com> | 2011-09-03 02:23:00 +0400 |
|---|---|---|
| committer | Ben Hutchings <bhutchings@solarflare.com> | 2012-01-27 04:10:45 +0400 |
| commit | 1cb345220f135dcca24f01cc04cbb97a8242d419 (patch) | |
| tree | 059ec907cd50bd10114bd942d0ffbfa7fd080aa2 /drivers/net/ethernet/sfc/ethtool.c | |
| parent | 788ec41cc843f12e8d0eba5f2b37af18b76654a5 (diff) | |
| download | linux-1cb345220f135dcca24f01cc04cbb97a8242d419.tar.xz | |
sfc: Hold efx_nic::stats_lock while reading efx_nic::mac_stats
efx_nic::stats_lock is used to serialise stats updates, but each
reader was dropping it before it finished reading efx_nic::mac_stats.
If there were concurrent stats reads using procfs, or one using procfs
and one using ethtool, an update could race with a read. On a 32-bit
system, the reader could see word-tearing of 64-bit stats (32 bits of
the old value and 32 bits of the new).
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Diffstat (limited to 'drivers/net/ethernet/sfc/ethtool.c')
| -rw-r--r-- | drivers/net/ethernet/sfc/ethtool.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/net/ethernet/sfc/ethtool.c b/drivers/net/ethernet/sfc/ethtool.c index 52c9ee4c8aa3..55a25b14d304 100644 --- a/drivers/net/ethernet/sfc/ethtool.c +++ b/drivers/net/ethernet/sfc/ethtool.c @@ -489,13 +489,14 @@ static void efx_ethtool_get_stats(struct net_device *net_dev, const struct efx_ethtool_stat *stat; struct efx_channel *channel; struct efx_tx_queue *tx_queue; - struct rtnl_link_stats64 temp; int i; EFX_BUG_ON_PARANOID(stats->n_stats != EFX_ETHTOOL_NUM_STATS); + spin_lock_bh(&efx->stats_lock); + /* Update MAC and NIC statistics */ - dev_get_stats(net_dev, &temp); + efx->type->update_stats(efx); /* Fill detailed statistics buffer */ for (i = 0; i < EFX_ETHTOOL_NUM_STATS; i++) { @@ -525,6 +526,8 @@ static void efx_ethtool_get_stats(struct net_device *net_dev, break; } } + + spin_unlock_bh(&efx->stats_lock); } static void efx_ethtool_self_test(struct net_device *net_dev, |