This patchset adds support for logging MCDI (Management-Controller-to-
Driver Interface) interactions between the sfc driver and a bound device,
to aid in debugging.
Solarflare has a tool to decode the resulting traces and will look to
open-source this if there is any external interest, but the protocol is
already detailed in drivers/net/ethernet/sfc/mcdi_pcol.h.
The logging buffer we allocate per MCDI context is a work area for
constructing each individual message before logging it with netif_info.
The reason the buffer is long-lived is simply to avoid the overhead of
allocating and freeing it every MCDI call, since MCDIs are already known
to be serialised for other reasons.
--
v4: remove patch #4, which has already been applied via sshah
v3: add some explanations to cover letter and patch #4
v2: avoid long lines in cover letter; fix multiline comment style
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Signed-off-by: David S. Miller <davem@davemloft.net>