• Rick Jones's avatar
    net: add explicit logging and stat for neighbour table overflow · fb811395
    Rick Jones authored
    Add an explicit neighbour table overflow message (ratelimited) and
    statistic to make diagnosing neighbour table overflows tractable in
    the wild.
    
    Diagnosing a neighbour table overflow can be quite difficult in the wild
    because there is no explicit dmesg logged.  Callers to neighbour code
    seem to use net_dbg_ratelimit when the neighbour call fails which means
    the "base message" is not emitted and the callback suppressed messages
    from the ratelimiting can end-up juxtaposed with unrelated messages.
    Further, a forced garbage collection will increment a stat on each call
    whether it was successful in freeing-up a table entry or not, so that
    statistic is only a hint.  So, add a net_info_ratelimited message and
    explicit statistic to the neighbour code.
    Signed-off-by: 's avatarRick Jones <rick.jones2@hp.com>
    Signed-off-by: 's avatarDavid S. Miller <davem@davemloft.net>
    fb811395
neighbour.h 14.2 KB