Re: [PATCH] mac80211: change workqueue back to non-freezeable

[Johannes Berg <johannes@sipsolutions.net>]

[-- Attachment #1: Type: text/plain, Size: 1707 bytes --]

On Fri, 2009-01-23 at 23:12 -0500, Bob Copeland wrote:
> [apologies for resend, forgot to cc wireless]
> 
> Commit 59959a6150c8af737898e83f727e824dbed7b0fa made the mac80211
> workqueue freezeable to prevent us from doing any work after the 
> driver went away.  This was fine before mac80211 had any suspend 
> support.
> 
> However, now we want to flush this workqueue in suspend().  Because
> the thread for a freezeable workqueue is stopped before the device
> class suspend() is called, flush_workqueue() will hang in the
> suspend-to-disk case.
> 
> Converting it back to a non-freezeable queue will keep suspend from
> hanging.  Moreover, since we flush the workqueue under RTNL and
> userspace is stopped, there won't be any new work in the workqueue
> until after resume.  Thus we still don't have to worry about pinging
> the AP without hardware.

Good catch! Do we have to freeze the workqueue ourselves manually or
something, to avoid drivers adding work to it?

> Signed-off-by: Bob Copeland <me@bobcopeland.com>
> ---
>  net/mac80211/main.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/net/mac80211/main.c b/net/mac80211/main.c
> index a100793..a109c06 100644
> --- a/net/mac80211/main.c
> +++ b/net/mac80211/main.c
> @@ -859,7 +859,7 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
>  	mdev->set_multicast_list = ieee80211_master_set_multicast_list;
>  
>  	local->hw.workqueue =
> -		create_freezeable_workqueue(wiphy_name(local->hw.wiphy));
> +		create_singlethread_workqueue(wiphy_name(local->hw.wiphy));
>  	if (!local->hw.workqueue) {
>  		result = -ENOMEM;
>  		goto fail_workqueue;
> -- 
> 1.6.0.6
> 

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 836 bytes --]