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| author | Vladimir Oltean <vladimir.oltean@nxp.com> | 2022-06-29 21:30:07 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-06-30 11:37:09 -0700 |
| commit | 58bf4db695287c4bb2a5fc9fc12c78fdd4c36894 (patch) | |
| tree | e16726f5048fb876ce120bf627d7c07cb6d98ea1 /drivers/net | |
| parent | 839b92fede7ba308f1a475aa00fea55f63b7fccf (diff) | |
| download | lwn-58bf4db695287c4bb2a5fc9fc12c78fdd4c36894.tar.gz lwn-58bf4db695287c4bb2a5fc9fc12c78fdd4c36894.zip | |
net: dsa: felix: fix race between reading PSFP stats and port stats
Both PSFP stats and the port stats read by ocelot_check_stats_work() are
indirectly read through the same mechanism - write to STAT_CFG:STAT_VIEW,
read from SYS:STAT:CNT[n].
It's just that for port stats, we write STAT_VIEW with the index of the
port, and for PSFP stats, we write STAT_VIEW with the filter index.
So if we allow them to run concurrently, ocelot_check_stats_work() may
change the view from vsc9959_psfp_counters_get(), and vice versa.
Fixes: 7d4b564d6add ("net: dsa: felix: support psfp filter on vsc9959")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20220629183007.3808130-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/dsa/ocelot/felix_vsc9959.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c index 570d0204b7be..9c27b9b0128d 100644 --- a/drivers/net/dsa/ocelot/felix_vsc9959.c +++ b/drivers/net/dsa/ocelot/felix_vsc9959.c @@ -1886,6 +1886,8 @@ static void vsc9959_psfp_sgi_table_del(struct ocelot *ocelot, static void vsc9959_psfp_counters_get(struct ocelot *ocelot, u32 index, struct felix_stream_filter_counters *counters) { + mutex_lock(&ocelot->stats_lock); + ocelot_rmw(ocelot, SYS_STAT_CFG_STAT_VIEW(index), SYS_STAT_CFG_STAT_VIEW_M, SYS_STAT_CFG); @@ -1900,6 +1902,8 @@ static void vsc9959_psfp_counters_get(struct ocelot *ocelot, u32 index, SYS_STAT_CFG_STAT_VIEW(index) | SYS_STAT_CFG_STAT_CLEAR_SHOT(0x10), SYS_STAT_CFG); + + mutex_unlock(&ocelot->stats_lock); } static int vsc9959_psfp_filter_add(struct ocelot *ocelot, int port, |