Re: [RFC 13/19] staging: qlge: rewrite do while loop as for loop in qlge_sem_spinlock

From: Joe Perches
Date: Wed Jun 30 2021 - 06:58:14 EST


On Thu, 2021-06-24 at 19:22 +0800, Coiby Xu wrote:
> On Tue, Jun 22, 2021 at 10:20:36AM +0300, Dan Carpenter wrote:
> > On Mon, Jun 21, 2021 at 09:48:56PM +0800, Coiby Xu wrote:
> > > Since wait_count=30 > 0, the for loop is equivalent to do while
> > > loop. This commit also replaces 100 with UDELAY_DELAY.
[]
> > > diff --git a/drivers/staging/qlge/qlge_main.c b/drivers/staging/qlge/qlge_main.c
[]
> > > @@ -140,12 +140,13 @@ static int qlge_sem_trylock(struct qlge_adapter *qdev, u32 sem_mask)
> > >  int qlge_sem_spinlock(struct qlge_adapter *qdev, u32 sem_mask)
> > >  {
> > >   unsigned int wait_count = 30;
> > > + int count;
> > >
> > > - do {
> > > + for (count = 0; count < wait_count; count++) {
> > >   if (!qlge_sem_trylock(qdev, sem_mask))
> > >   return 0;
> > > - udelay(100);
> > > - } while (--wait_count);
> > > + udelay(UDELAY_DELAY);
> >
> > This is an interesting way to silence the checkpatch udelay warning. ;)
>
> I didn't know this could silence the warning :)

It also seems odd to have unsigned int wait_count and int count.

Maybe just use 30 in the loop without using wait_count at all.

I also think using UDELAY_DELAY is silly and essentially misleading
as it's also used as an argument value for mdelay

$ git grep -w UDELAY_DELAY
drivers/staging/qlge/qlge.h:#define UDELAY_DELAY 100
drivers/staging/qlge/qlge_main.c: udelay(UDELAY_DELAY);
drivers/staging/qlge/qlge_main.c: udelay(UDELAY_DELAY);
drivers/staging/qlge/qlge_mpi.c: mdelay(UDELAY_DELAY);
drivers/staging/qlge/qlge_mpi.c: mdelay(UDELAY_DELAY);
drivers/staging/qlge/qlge_mpi.c: mdelay(UDELAY_DELAY); /* 100ms */