From 25027c8409b4541611d0060077607d8ca70740df Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Thu, 8 Sep 2022 19:48:05 +0300 Subject: net: dsa: felix: check the 32-bit PSFP stats against overflow The Felix PSFP counters suffer from the same problem as the ocelot ndo_get_stats64 ones - they are 32-bit, so they can easily overflow and this can easily go undetected. Add a custom hook in ocelot_check_stats_work() through which driver specific actions can be taken, and update the stats for the existing PSFP filters from that hook. Previously, vsc9959_psfp_filter_add() and vsc9959_psfp_filter_del() were serialized with respect to each other via rtnl_lock(). However, with the new entry point into &psfp->sfi_list coming from the periodic worker, we now need an explicit mutex to serialize access to these lists. We used to keep a struct felix_stream_filter_counters on stack, through which vsc9959_psfp_stats_get() - a FLOW_CLS_STATS callback - would retrieve data from vsc9959_psfp_counters_get(). We need to become smarter about that in 3 ways: - we need to keep a persistent set of counters for each stream instead of keeping them on stack - we need to promote those counters from u32 to u64, and create a procedure that properly keeps 64-bit counters. Since we clear the hardware counters anyway, and we poll every 2 seconds, a simple increment of a u64 counter with a u32 value will perfectly do the job. - FLOW_CLS_STATS also expect incremental counters, so we also need to zeroize our u64 counters every time sch_flower calls us Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller --- include/soc/mscc/ocelot.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/soc/mscc/ocelot.h') diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h index e85fb3b15524..bc6ca1be08f3 100644 --- a/include/soc/mscc/ocelot.h +++ b/include/soc/mscc/ocelot.h @@ -729,6 +729,7 @@ struct ocelot_ops { struct flow_stats *stats); void (*cut_through_fwd)(struct ocelot *ocelot); void (*tas_clock_adjust)(struct ocelot *ocelot); + void (*update_stats)(struct ocelot *ocelot); }; struct ocelot_vcap_policer { @@ -766,6 +767,8 @@ struct ocelot_psfp_list { struct list_head stream_list; struct list_head sfi_list; struct list_head sgi_list; + /* Serialize access to the lists */ + struct mutex lock; }; enum ocelot_sb { -- cgit v1.2.3