Commit 52e2a99e authored Nov 25, 2012 by Emmanuel Grumbach Committed by Johannes Berg Nov 28, 2012

iwlwifi: read the Rx write pointer only once



The FH (DMA engine) tells the driver the index of the last
ready (closed) Rx buffer. This data is in closed_rb_num.
If we read this data several times we may get inconsistencies
between the code and the debug prints which can make it
harder to debug issues here.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

parent eea54c8e

drivers/net/wireless/iwlwifi/pcie/rx.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -698,7 +698,7 @@ static void iwl_pcie_rx_handle(struct iwl_trans *trans)

		/* uCode's read index (stored in shared DRAM) indicates the last Rx
		* buffer that the driver may process (last buffer filled by ucode). */
		r = le16_to_cpu(rxq->rb_stts->closed_rb_num) & 0x0FFF;
		r = le16_to_cpu(ACCESS_ONCE(rxq->rb_stts->closed_rb_num)) & 0x0FFF;
		i = rxq->read;

		/* Rx interrupt, but nothing sent from uCode */