From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wi0-f172.google.com ([209.85.212.172]:33822 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755716AbbA3NWS convert rfc822-to-8bit (ORCPT ); Fri, 30 Jan 2015 08:22:18 -0500 Received: by mail-wi0-f172.google.com with SMTP id h11so2993253wiw.5 for ; Fri, 30 Jan 2015 05:22:17 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1422623054.1919.18.camel@sipsolutions.net> References: <1422607287-12289-1-git-send-email-michal.kazior@tieto.com> <1422621086-28970-1-git-send-email-michal.kazior@tieto.com> <1422621086-28970-3-git-send-email-michal.kazior@tieto.com> <1422621903.1919.7.camel@sipsolutions.net> <1422623054.1919.18.camel@sipsolutions.net> Date: Fri, 30 Jan 2015 14:22:16 +0100 Message-ID: (sfid-20150130_142220_996474_92CF6E1F) Subject: Re: [PATCH v2 2/7] ath10k: implement chanctx API From: Michal Kazior To: Johannes Berg Cc: "ath10k@lists.infradead.org" , linux-wireless Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 30 January 2015 at 14:04, Johannes Berg wrote: > On Fri, 2015-01-30 at 14:02 +0100, Michal Kazior wrote: > >> I recall that at least there's one case where using these helpers is >> impossible: drv_config() which can be called while mac80211 is already >> holding iflist_mtx. ath10k needs to iterate over vifs and issue >> blocking commands sometimes so it can't use atomic/rcu versions >> either. > > If you wanted to use it, I wouldn't be averse to adding a locked version > that can only be used inside a few of such callbacks. With appropriate > lockdep warnings that would be safe enough, I think. You'd probably have to add quite a few mutex_lock(iflist_mtx) around drv_*() calls (not directly but somewhere at their call trees) to guarantee driver can use lock-free iterate() version (which doesn't exist yet). This could be tricky. Michał From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-wg0-x234.google.com ([2a00:1450:400c:c00::234]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1YHBWx-0005hE-2s for ath10k@lists.infradead.org; Fri, 30 Jan 2015 13:22:39 +0000 Received: by mail-wg0-f52.google.com with SMTP id y19so26816650wgg.11 for ; Fri, 30 Jan 2015 05:22:17 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1422623054.1919.18.camel@sipsolutions.net> References: <1422607287-12289-1-git-send-email-michal.kazior@tieto.com> <1422621086-28970-1-git-send-email-michal.kazior@tieto.com> <1422621086-28970-3-git-send-email-michal.kazior@tieto.com> <1422621903.1919.7.camel@sipsolutions.net> <1422623054.1919.18.camel@sipsolutions.net> Date: Fri, 30 Jan 2015 14:22:16 +0100 Message-ID: Subject: Re: [PATCH v2 2/7] ath10k: implement chanctx API From: Michal Kazior List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "ath10k" Errors-To: ath10k-bounces+kvalo=adurom.com@lists.infradead.org To: Johannes Berg Cc: linux-wireless , "ath10k@lists.infradead.org" T24gMzAgSmFudWFyeSAyMDE1IGF0IDE0OjA0LCBKb2hhbm5lcyBCZXJnIDxqb2hhbm5lc0BzaXBz b2x1dGlvbnMubmV0PiB3cm90ZToKPiBPbiBGcmksIDIwMTUtMDEtMzAgYXQgMTQ6MDIgKzAxMDAs IE1pY2hhbCBLYXppb3Igd3JvdGU6Cj4KPj4gSSByZWNhbGwgdGhhdCBhdCBsZWFzdCB0aGVyZSdz IG9uZSBjYXNlIHdoZXJlIHVzaW5nIHRoZXNlIGhlbHBlcnMgaXMKPj4gaW1wb3NzaWJsZTogZHJ2 X2NvbmZpZygpIHdoaWNoIGNhbiBiZSBjYWxsZWQgd2hpbGUgbWFjODAyMTEgaXMgYWxyZWFkeQo+ PiBob2xkaW5nIGlmbGlzdF9tdHguIGF0aDEwayBuZWVkcyB0byBpdGVyYXRlIG92ZXIgdmlmcyBh bmQgaXNzdWUKPj4gYmxvY2tpbmcgY29tbWFuZHMgc29tZXRpbWVzIHNvIGl0IGNhbid0IHVzZSBh dG9taWMvcmN1IHZlcnNpb25zCj4+IGVpdGhlci4KPgo+IElmIHlvdSB3YW50ZWQgdG8gdXNlIGl0 LCBJIHdvdWxkbid0IGJlIGF2ZXJzZSB0byBhZGRpbmcgYSBsb2NrZWQgdmVyc2lvbgo+IHRoYXQg Y2FuIG9ubHkgYmUgdXNlZCBpbnNpZGUgYSBmZXcgb2Ygc3VjaCBjYWxsYmFja3MuIFdpdGggYXBw cm9wcmlhdGUKPiBsb2NrZGVwIHdhcm5pbmdzIHRoYXQgd291bGQgYmUgc2FmZSBlbm91Z2gsIEkg dGhpbmsuCgpZb3UnZCBwcm9iYWJseSBoYXZlIHRvIGFkZCBxdWl0ZSBhIGZldyBtdXRleF9sb2Nr KGlmbGlzdF9tdHgpIGFyb3VuZApkcnZfKigpIGNhbGxzIChub3QgZGlyZWN0bHkgYnV0IHNvbWV3 aGVyZSBhdCB0aGVpciBjYWxsIHRyZWVzKSB0bwpndWFyYW50ZWUgZHJpdmVyIGNhbiB1c2UgbG9j ay1mcmVlIGl0ZXJhdGUoKSB2ZXJzaW9uICh3aGljaCBkb2Vzbid0CmV4aXN0IHlldCkuIFRoaXMg Y291bGQgYmUgdHJpY2t5LgoKCk1pY2hhxYIKCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fCmF0aDEwayBtYWlsaW5nIGxpc3QKYXRoMTBrQGxpc3RzLmluZnJh ZGVhZC5vcmcKaHR0cDovL2xpc3RzLmluZnJhZGVhZC5vcmcvbWFpbG1hbi9saXN0aW5mby9hdGgx MGsK