From: Sara Sharon <[email protected]> When there is a reorder timeout, we may get to a situation where we have the timeout latency for all the next 64 frames. This happens since NSSN is behind for a while, and the driver won't release the frames, since it is not allowed by NSSN. As a result the frame is stored in the reorder buffer although there is no hole, and released 100 ms later. Add a direct comparison to the reorder buffer head, and release immediately if possible.
For example: Frame 0 is missed. We receive frame 1, and store it in the buffer. After 100 ms, frame 1 is released and reorder buffer head is 2. We then receive frame 2, with NSSN 0, and store it instead of releasing it. Signed-off-by: Sara Sharon <[email protected]> Signed-off-by: Luca Coelho <[email protected]> --- drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c b/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c index b84756dc9d6c..9852a4d62337 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c @@ -719,6 +719,22 @@ static bool iwl_mvm_reorder(struct iwl_mvm *mvm, return false; } + /* + * release immediately if there are no stored frames, and the sn is + * equal to the head. + * This can happen due to reorder timer, where NSSN is behind head_sn. + * When we released everything, and we got the next frame in the + * sequence, according to the NSSN we can't release immediately, + * while technically there is no hole and we can move forward. + */ + if (!buffer->num_stored && sn == buffer->head_sn) { + if (!amsdu || last_subframe) + buffer->head_sn = ieee80211_sn_inc(buffer->head_sn); + /* No need to update AMSDU last SN - we are moving the head */ + spin_unlock_bh(&buffer->lock); + return false; + } + index = sn % buffer->buf_size; /* -- 2.14.2
