Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751482AbdI3GRp (ORCPT ); Sat, 30 Sep 2017 02:17:45 -0400 Received: from mail-qt0-f196.google.com ([209.85.216.196]:48058 "EHLO mail-qt0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750933AbdI3GRn (ORCPT ); Sat, 30 Sep 2017 02:17:43 -0400 X-Google-Smtp-Source: AOwi7QDffcW3+uqHGUQP0BrZZ68srcbp1Reotf7BGedUCI5hHQdJTDfVRvws5q9PYe7QGAldeBTILX5ZT0seZckuQQE= MIME-Version: 1.0 In-Reply-To: References: <1506734581-10932-1-git-send-email-srishtishar@gmail.com> From: Srishti Sharma Date: Sat, 30 Sep 2017 11:47:42 +0530 Message-ID: Subject: Re: [Outreachy kernel] [PATCH] Staging: rtl8188eu: core: Use list_entry instead of container_of To: Julia Lawall Cc: Greg KH , devel@driverdev.osuosl.org, Linux kernel mailing list , outreachy-kernel Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6027 Lines: 167 On Sat, Sep 30, 2017 at 11:36 AM, Julia Lawall wrote: > > > On Sat, 30 Sep 2017, Srishti Sharma wrote: > >> On Sat, Sep 30, 2017 at 10:35 AM, Julia Lawall wrote: >> > >> > >> > On Sat, 30 Sep 2017, Srishti Sharma wrote: >> > >> >> For variables of the type struct list_head* use list_entry to access >> >> the current list element instead of using container_of. >> >> Done using the following semantic patch by coccinelle. >> >> >> >> @r@ >> >> identifier e; >> >> struct list_head* l; >> >> @@ >> >> >> >> <... when != l == NULL >> >> l; >> >> ...> >> > I don't see what is the goal of the above code. The list_head variable is >> > not going to be in a statement by itself. There is also no need to check >> > for l being NULL. If it is NULL, the original code is incorrect too. >> >> Since only those container_of are to replaced with list_entry which >> have a variable of type list_head* , I wanted to check if it occurs >> anywhere before >> container_of , > > Why? If it is a list, then it seems appropriate to access it using > list_head. > >> which it only does in it's declaration , because it >> can't be in any >> statement by itself . I think it will be better to write . >> >> @r@ >> identifier e; >> struct list_head* l; >> @@ >> >> <... >> container_of(l,...); >> ...> > > This doesn't ensure that there is a preceding container_of, if that is > what you are trying to do. The problem is that <... P ...> finds 0 or > more occurrences of pattern P, not 1 or more occurrences. 1 or more > occurrences is <+... P ...+>. But it would be simpler if you want an > occurrence of container_of before the thing you are transforming to put > > container_of(l,...); > ... > e = ... > > But this doesn't make sense either, partly because the preceding > container_of is just not needed, and also because a container_of would not > be in a statement by itself. In Coccinelle, when you put a ; after > something is means that the thing is a complete statement, not just the > end half of a statement. So , I guess we can simply write. e = -container_of +list_entry (l,...) Regards, Srishti > > julia > >> e = >> -container_of >> +list_entry >> ( >> ....) >> >> >> ( >> >> e = >> >> -container_of >> >> +list_entry >> >> ( >> >> ...) >> >> ) >> > >> > Here you don't need the outer ( ). This makes a disjunction with only >> > one choice. Since there is only one choice, you don't need the >> > disjunction. >> >> Thanks a lot , for pointing out the errors . >> >> Regards, >> Srishti >> > julia >> > >> >> Signed-off-by: Srishti Sharma >> >> --- >> >> drivers/staging/rtl8188eu/core/rtw_sta_mgt.c | 12 ++++++------ >> >> 1 file changed, 6 insertions(+), 6 deletions(-) >> >> >> >> diff --git a/drivers/staging/rtl8188eu/core/rtw_sta_mgt.c b/drivers/staging/rtl8188eu/core/rtw_sta_mgt.c >> >> index 22cf362..f9df4ac 100644 >> >> --- a/drivers/staging/rtl8188eu/core/rtw_sta_mgt.c >> >> +++ b/drivers/staging/rtl8188eu/core/rtw_sta_mgt.c >> >> @@ -152,8 +152,8 @@ u32 _rtw_free_sta_priv(struct sta_priv *pstapriv) >> >> while (phead != plist) { >> >> int i; >> >> >> >> - psta = container_of(plist, struct sta_info, >> >> - hash_list); >> >> + psta = list_entry(plist, struct sta_info, >> >> + hash_list); >> >> plist = plist->next; >> >> >> >> for (i = 0; i < 16; i++) { >> >> @@ -323,7 +323,7 @@ u32 rtw_free_stainfo(struct adapter *padapter, struct sta_info *psta) >> >> plist = phead->next; >> >> >> >> while (!list_empty(phead)) { >> >> - prframe = container_of(plist, struct recv_frame, list); >> >> + prframe = list_entry(plist, struct recv_frame, list); >> >> >> >> plist = plist->next; >> >> >> >> @@ -399,7 +399,7 @@ void rtw_free_all_stainfo(struct adapter *padapter) >> >> plist = phead->next; >> >> >> >> while (phead != plist) { >> >> - psta = container_of(plist, struct sta_info, hash_list); >> >> + psta = list_entry(plist, struct sta_info, hash_list); >> >> >> >> plist = plist->next; >> >> >> >> @@ -435,7 +435,7 @@ struct sta_info *rtw_get_stainfo(struct sta_priv *pstapriv, u8 *hwaddr) >> >> plist = phead->next; >> >> >> >> while (phead != plist) { >> >> - psta = container_of(plist, struct sta_info, hash_list); >> >> + psta = list_entry(plist, struct sta_info, hash_list); >> >> >> >> if ((!memcmp(psta->hwaddr, addr, ETH_ALEN)) == true) { >> >> /* if found the matched address */ >> >> @@ -493,7 +493,7 @@ u8 rtw_access_ctrl(struct adapter *padapter, u8 *mac_addr) >> >> phead = get_list_head(pacl_node_q); >> >> plist = phead->next; >> >> while (phead != plist) { >> >> - paclnode = container_of(plist, struct rtw_wlan_acl_node, list); >> >> + paclnode = list_entry(plist, struct rtw_wlan_acl_node, list); >> >> plist = plist->next; >> >> >> >> if (!memcmp(paclnode->addr, mac_addr, ETH_ALEN)) { >> >> -- >> >> 2.7.4 >> >> >> >> -- >> >> You received this message because you are subscribed to the Google Groups "outreachy-kernel" group. >> >> To unsubscribe from this group and stop receiving emails from it, send an email to outreachy-kernel+unsubscribe@googlegroups.com. >> >> To post to this group, send email to outreachy-kernel@googlegroups.com. >> >> To view this discussion on the web visit https://groups.google.com/d/msgid/outreachy-kernel/1506734581-10932-1-git-send-email-srishtishar%40gmail.com. >> >> For more options, visit https://groups.google.com/d/optout. >> >> >>