Re: [PATCH] staging: r8188eu: remove unwanted variable implementation

From: Julia Lawall
Date: Tue Nov 01 2022 - 16:46:04 EST




On Wed, 2 Nov 2022, Deepak R Varma wrote:

> On Tue, Nov 01, 2022 at 06:14:01PM +0100, Julia Lawall wrote:
> >
> >
> > On Tue, 1 Nov 2022, Deepak R Varma wrote:
> >
> > > Local variables intended as the function return value are
> > > initialized but their value does not change during function
> > > execution. The initial value assigned to the variable is simply
> > > returned to the caller. This makes the variable declaration
> > > unnecessary and the initial value can be directly returned.
> >
> > I think it would be better to make an argument for each case as to why the
> > change is correct, and no more interesting return value is needed. For
> > example, looking at the code in
> > drivers/staging/r8188eu/hal/rtl8188eu_xmit.c, it seems that the variable
> > pull was used in a more interesting way previously, but some previous
> > patches removed the relevant code.
>
> Thank you Julia for the hints. I learned that git blame will not show commits
> associated with deleted/replaced lines. Used pickaxe tool to identify the old
> commits. It was good learning. Thank you. v2 is submitted for review and feedback.

OK, I just did git log -p and looked through the commits.

You can also use the argument eg -G pull to find commits that change the
number of occurrences of pull.

julia


>
> >
> > julia
> >
> > >
> > > The patch is produced using the following coccicheck options:
> > > COCCI=./scripts/coccinelle/misc/returnvar.cocci
> > > M=driver/staging/r8188eu/
> > > MODE=patch
> > >
> > > Signed-off-by: Deepak R Varma <drv@xxxxxxxxx>
> > > ---
> > > drivers/staging/r8188eu/core/rtw_ap.c | 5 ++---
> > > drivers/staging/r8188eu/core/rtw_recv.c | 3 +--
> > > drivers/staging/r8188eu/hal/rtl8188eu_xmit.c | 3 +--
> > > drivers/staging/r8188eu/os_dep/ioctl_linux.c | 4 +---
> > > 4 files changed, 5 insertions(+), 10 deletions(-)
> > >
> > > diff --git a/drivers/staging/r8188eu/core/rtw_ap.c b/drivers/staging/r8188eu/core/rtw_ap.c
> > > index 24eb8dce9bfe..9eaf345e6a00 100644
> > > --- a/drivers/staging/r8188eu/core/rtw_ap.c
> > > +++ b/drivers/staging/r8188eu/core/rtw_ap.c
> > > @@ -1020,7 +1020,6 @@ u8 ap_free_sta(struct adapter *padapter, struct sta_info *psta,
> > > int rtw_sta_flush(struct adapter *padapter)
> > > {
> > > struct list_head *phead, *plist;
> > > - int ret = 0;
> > > struct sta_info *psta = NULL;
> > > struct sta_priv *pstapriv = &padapter->stapriv;
> > > struct mlme_ext_priv *pmlmeext = &padapter->mlmeextpriv;
> > > @@ -1028,7 +1027,7 @@ int rtw_sta_flush(struct adapter *padapter)
> > > u8 bc_addr[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
> > >
> > > if ((pmlmeinfo->state & 0x03) != WIFI_FW_AP_STATE)
> > > - return ret;
> > > + return 0;
> > >
> > > spin_lock_bh(&pstapriv->asoc_list_lock);
> > > phead = &pstapriv->asoc_list;
> > > @@ -1051,7 +1050,7 @@ int rtw_sta_flush(struct adapter *padapter)
> > >
> > > associated_clients_update(padapter, true);
> > >
> > > - return ret;
> > > + return 0;
> > > }
> > >
> > > /* called > TSR LEVEL for USB or SDIO Interface*/
> > > diff --git a/drivers/staging/r8188eu/core/rtw_recv.c b/drivers/staging/r8188eu/core/rtw_recv.c
> > > index 4b68a543f68b..94f85cd7038d 100644
> > > --- a/drivers/staging/r8188eu/core/rtw_recv.c
> > > +++ b/drivers/staging/r8188eu/core/rtw_recv.c
> > > @@ -1415,7 +1415,6 @@ static int amsdu_to_msdu(struct adapter *padapter, struct recv_frame *prframe)
> > >
> > > struct recv_priv *precvpriv = &padapter->recvpriv;
> > > struct __queue *pfree_recv_queue = &precvpriv->free_recv_queue;
> > > - int ret = _SUCCESS;
> > >
> > > nr_subframes = 0;
> > >
> > > @@ -1513,7 +1512,7 @@ static int amsdu_to_msdu(struct adapter *padapter, struct recv_frame *prframe)
> > > prframe->len = 0;
> > > rtw_free_recvframe(prframe, pfree_recv_queue);/* free this recv_frame */
> > >
> > > - return ret;
> > > + return _SUCCESS;
> > > }
> > >
> > > static bool check_indicate_seq(struct recv_reorder_ctrl *preorder_ctrl, u16 seq_num)
> > > diff --git a/drivers/staging/r8188eu/hal/rtl8188eu_xmit.c b/drivers/staging/r8188eu/hal/rtl8188eu_xmit.c
> > > index 8e4a5acc0b18..6d1f56d1f9d7 100644
> > > --- a/drivers/staging/r8188eu/hal/rtl8188eu_xmit.c
> > > +++ b/drivers/staging/r8188eu/hal/rtl8188eu_xmit.c
> > > @@ -149,7 +149,6 @@ static void fill_txdesc_phy(struct pkt_attrib *pattrib, __le32 *pdw)
> > >
> > > static s32 update_txdesc(struct xmit_frame *pxmitframe, u8 *pmem, s32 sz, u8 bagg_pkt)
> > > {
> > > - int pull = 0;
> > > uint qsel;
> > > u8 data_rate, pwr_status, offset;
> > > struct adapter *adapt = pxmitframe->padapter;
> > > @@ -295,7 +294,7 @@ static s32 update_txdesc(struct xmit_frame *pxmitframe, u8 *pmem, s32 sz, u8 bag
> > > ODM_SetTxAntByTxInfo_88E(&haldata->odmpriv, pmem, pattrib->mac_id);
> > >
> > > rtl8188eu_cal_txdesc_chksum(ptxdesc);
> > > - return pull;
> > > + return 0;
> > > }
> > >
> > > /* for non-agg data frame or management frame */
> > > diff --git a/drivers/staging/r8188eu/os_dep/ioctl_linux.c b/drivers/staging/r8188eu/os_dep/ioctl_linux.c
> > > index 8516e253bb03..59a97c5fb80c 100644
> > > --- a/drivers/staging/r8188eu/os_dep/ioctl_linux.c
> > > +++ b/drivers/staging/r8188eu/os_dep/ioctl_linux.c
> > > @@ -2979,8 +2979,6 @@ static int rtw_p2p_set(struct net_device *dev,
> > > struct iw_request_info *info,
> > > union iwreq_data *wrqu, char *extra)
> > > {
> > > - int ret = 0;
> > > -
> > > if (!memcmp(extra, "enable =", 7)) {
> > > rtw_wext_p2p_enable(dev, info, wrqu, &extra[7]);
> > > } else if (!memcmp(extra, "setDN =", 6)) {
> > > @@ -3027,7 +3025,7 @@ static int rtw_p2p_set(struct net_device *dev,
> > > rtw_p2p_set_persistent(dev, info, wrqu, &extra[11]);
> > > }
> > >
> > > - return ret;
> > > + return 0;
> > > }
> > >
> > > static int rtw_p2p_get2(struct net_device *dev,
> > > --
> > > 2.34.1
> > >
> > >
> > >
> > >
> > >
> >
>
>
>