Re: [PATCH] PCI/bwctrl: Remove unused pcie_bwctrl_lbms_rwsem

[Paul E. McKenney]

On Thu, May 08, 2025 at 07:08:45PM +1000, Stephen Rothwell wrote:
> Hi Paul,
> 
> On Wed, 7 May 2025 15:04:57 -0700 "Paul E. McKenney" <paulmck@xxxxxxxxxx> wrote:
> >
> > PCI/bwctrl: Remove unused pcie_bwctrl_lbms_rwsem
> > 
> > Builds with CONFIG_PREEMPT_RT=y get the following build error:
> > 
> > drivers/pci/pcie/bwctrl.c:56:22: error: ‘pcie_bwctrl_lbms_rwsem’ defined but not used [-Werror=unused-variable]
> > 
> > Therefore, remove this unused variable.  Perhaps this should be folded
> > into the commit shown below.
> > 
> > Fixes: 0238f352a63a ("PCI/bwctrl: Replace lbms_count with PCI_LINK_LBMS_SEEN flag")
> > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> > Cc: "Ilpo Järvinen" <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> > Cc: <linux-pci@xxxxxxxxxxxxxxx>
> > 
> > diff --git a/drivers/pci/pcie/bwctrl.c b/drivers/pci/pcie/bwctrl.c
> > index fdafa20e4587d..841ab8725aff7 100644
> > --- a/drivers/pci/pcie/bwctrl.c
> > +++ b/drivers/pci/pcie/bwctrl.c
> > @@ -53,7 +53,6 @@ struct pcie_bwctrl_data {
> >   * (using just one rwsem triggers "possible recursive locking detected"
> >   * warning).
> >   */
> > -static DECLARE_RWSEM(pcie_bwctrl_lbms_rwsem);
> >  static DECLARE_RWSEM(pcie_bwctrl_setspeed_rwsem);
> >  
> >  static bool pcie_valid_speed(enum pci_bus_speed speed)
> 
> I added that to linux-next today and will remove it when it is no
> longer needed.

Thank you, Stephen!

Ilpo, I look forward to seeing this patch replaced by your improved
version with better comments.

							Thanx, Paul