page pool and XDP should not be accessed from IRQ context which may happen if drivers try to clean up XDP TX with NAPI budget of 0. Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> --- CC: corbet@xxxxxxx CC: linux-doc@xxxxxxxxxxxxxxx --- Documentation/networking/napi.rst | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/Documentation/networking/napi.rst b/Documentation/networking/napi.rst index a7a047742e93..7bf7b95c4f7a 100644 --- a/Documentation/networking/napi.rst +++ b/Documentation/networking/napi.rst @@ -65,15 +65,16 @@ argument - drivers can process completions for any number of Tx packets but should only process up to ``budget`` number of Rx packets. Rx processing is usually much more expensive. -In other words, it is recommended to ignore the budget argument when -performing TX buffer reclamation to ensure that the reclamation is not -arbitrarily bounded; however, it is required to honor the budget argument -for RX processing. +In other words for Rx processing the ``budget`` argument limits how many +packets driver can process in a single poll. Rx specific APIs like page +pool or XDP cannot be used at all when ``budget`` is 0. +skb Tx processing should happen regardless of the ``budget``, but if +the argument is 0 driver cannot call any XDP (or page pool) APIs. .. warning:: - The ``budget`` argument may be 0 if core tries to only process Tx completions - and no Rx packets. + The ``budget`` argument may be 0 if core tries to only process + skb Tx completions and no Rx or XDP packets. The poll method returns the amount of work done. If the driver still has outstanding work to do (e.g. ``budget`` was exhausted) -- 2.41.0
