On Mon, May 21, 2018 at 10:37:01PM +0200, Niklas Cassel wrote:

On Thu, May 17, 2018 at 03:26:25PM -0700, Adrian Chadd wrote:

quoted

On Thu, 17 May 2018 at 16:16, Niklas Cassel [off-list ref]
wrote:

quoted

diff --git a/drivers/net/wireless/ath/ath10k/txrx.c

b/drivers/net/wireless/ath/ath10k/txrx.c

quoted

index cda164f6e9f6..1d3b2d2c3fee 100644

--- a/drivers/net/wireless/ath/ath10k/txrx.c
+++ b/drivers/net/wireless/ath/ath10k/txrx.c

@@ -95,6 +95,9 @@ int ath10k_txrx_tx_unref(struct ath10k_htt *htt,
                 wake_up(&htt->empty_tx_wq);
         spin_unlock_bh(&htt->tx_lock);

quoted

+       if (htt->num_pending_tx <= 3 && !list_empty(&ar->txqs))
+               ath10k_mac_tx_push_pending(ar);
+

Just sanity checking - what's protecting htt->num_pending_tx? or is it
serialised some other way?

[...]

I can't see that any of the examples applies, but let's add READ_ONCE(),
to make sure that the compiler doesn't try to optimize this.

Couldn't you just move the num_pending_tx read inside tx_lock which is 2 lines
above?  I think all the other manipulations are protected by tx_lock.

-- 
Bob Copeland %% https://bobcopeland.com/