Re: [PATCH net-next 1/8] net: ipa: maintain bitmap of suspend-enabled endpoints

[Alex Elder]

On 4/18/24 6:52 PM, Bryan O'Donoghue wrote:
> On 18/04/2024 21:47, Alex Elder wrote:
> > Keep track of which endpoints have the SUSPEND IPA interrupt enabled
> > in a variable-length bitmap.  This will be used in the next patch to
> > allow the SUSPEND interrupt type to be disabled except when needed.
> >
> > Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
> > ---
> >   drivers/net/ipa/ipa_interrupt.c | 19 +++++++++++++++++--
> >   1 file changed, 17 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/ipa/ipa_interrupt.c 
> > b/drivers/net/ipa/ipa_interrupt.c
> > index c44ec05f71e6f..0e8d4e43275ea 100644
> > --- a/drivers/net/ipa/ipa_interrupt.c
> > +++ b/drivers/net/ipa/ipa_interrupt.c
> > @@ -37,11 +37,13 @@
> >    * @ipa:        IPA pointer
> >    * @irq:        Linux IRQ number used for IPA interrupts
> >    * @enabled:        Mask indicating which interrupts are enabled
> > + * @suspend_enabled:    Bitmap of endpoints with the SUSPEND 
> > interrupt enabled
> >    */
> >   struct ipa_interrupt {
> >       struct ipa *ipa;
> >       u32 irq;
> >       u32 enabled;
> > +    unsigned long *suspend_enabled;
> >   };
> >   /* Clear the suspend interrupt for all endpoints that signaled it */
> > @@ -211,6 +213,7 @@ static void ipa_interrupt_suspend_control(struct 
> > ipa_interrupt *interrupt,
> >           val |= mask;
> >       else
> >           val &= ~mask;
> > +    __change_bit(endpoint_id, interrupt->suspend_enabled);
> >       iowrite32(val, ipa->reg_virt + offset);
> >   }
> > @@ -246,7 +249,16 @@ int ipa_interrupt_config(struct ipa *ipa)
> >       interrupt->ipa = ipa;
> > -    /* Disable all IPA interrupt types */
> > +    /* Initially all IPA interrupt types are disabled */
> > +    interrupt->enabled = 0;
> > +    interrupt->suspend_enabled = bitmap_zalloc(ipa->endpoint_count,
> > +                           GFP_KERNEL);
>
> why not use devm_bitmap_zalloc() instead and skip managing the cleanup ?

I don't use the devm_*() variants in the IPA driver.

I know I can, but if I'm make the switch I want to
do it everywhere.  Not now.

Thanks for the review.

					-Alex

> > +    if (!interrupt->suspend_enabled) {
> > +        ret = -ENOMEM;
> > +        goto err_kfree;
> > +    }
> > +
> > +    /* Disable IPA interrupt types */
> >       reg = ipa_reg(ipa, IPA_IRQ_EN);
> >       iowrite32(0, ipa->reg_virt + reg_offset(reg));
> > @@ -254,7 +266,7 @@ int ipa_interrupt_config(struct ipa *ipa)
> >                      "ipa", interrupt);
> >       if (ret) {
> >           dev_err(dev, "error %d requesting \"ipa\" IRQ\n", ret);
> > -        goto err_kfree;
> > +        goto err_free_bitmap;
> >       }
> >       ret = dev_pm_set_wake_irq(dev, irq);
> > @@ -270,6 +282,8 @@ int ipa_interrupt_config(struct ipa *ipa)
> >   err_free_irq:
> >       free_irq(interrupt->irq, interrupt);
> > +err_free_bitmap:
> > +    bitmap_free(interrupt->suspend_enabled);
> >   err_kfree:
> >       kfree(interrupt);
>
> You could also use devm_kzalloc() and do away with the kfree()s you have 
> here on the probe path.
>
> > @@ -286,6 +300,7 @@ void ipa_interrupt_deconfig(struct ipa *ipa)
> >       dev_pm_clear_wake_irq(dev);
> >       free_irq(interrupt->irq, interrupt);
> > +    bitmap_free(interrupt->suspend_enabled);
> >   }
> >   /* Initialize the IPA interrupt structure */
>
> Just suggestions though.
>
> Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>