Re: [PATCH v4 06/21] thermal/drivers/db8500: convert to use devm_request*_irq_probe()

[Yangtao Li]

Hi Dmitry,

On 2023/7/10 19:25, Dmitry Baryshkov wrote:

> On 10/07/2023 12:59, Yangtao Li wrote:
> > There are more than 700 calls to devm_request_threaded_irq method and
> > more than 1000 calls to devm_request_irq method. Most drivers only
> > request one interrupt resource, and these error messages are basically
> > the same. If error messages are printed everywhere, more than 2000 lines
> > of code can be saved by removing the msg in the driver.
> >
> > And tglx point out that:
> >
> >    If we actually look at the call sites of
> >    devm_request_threaded_irq() then the vast majority of them print 
> > more or
> >    less lousy error messages. A quick grep/sed/awk/sort/uniq revealed
> >
> >       519 messages total (there are probably more)
> >
> >       352 unique messages
> >
> >       323 unique messages after lower casing
> >
> >           Those 323 are mostly just variants of the same patterns with
> >           slight modifications in formatting and information provided.
> >
> >       186 of these messages do not deliver any useful information,
> >           e.g. "no irq", "
> >
> >       The most useful one of all is: "could request wakeup irq: %d"
> >
> >    So there is certainly an argument to be made that this particular
> >    function should print a well formatted and informative error message.
> >
> >    It's not a general allocator like kmalloc(). It's specialized and 
> > in the
> >    vast majority of cases failing to request the interrupt causes the
> >    device probe to fail. So having proper and consistent information why
> >    the device cannot be used _is_ useful.
> >
> > So convert to use devm_request*_irq_probe() API, which ensure that all
> > error handling branches print error information.
> >
> > In this way, when this function fails, the upper-layer functions can
> > directly return an error code without missing debugging information.
> > Otherwise, the error message will be printed redundantly or missing.
> >
> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Cc: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> > Cc: "Uwe Kleine-König" <u.kleine-koenig@xxxxxxxxxxxxxx>
> > Cc: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> > Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> > Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
> > ---
> >   drivers/thermal/db8500_thermal.c | 16 ++++++----------
> >   drivers/thermal/qcom/lmh.c       |  7 +++----
>
> Please split LMH to a separate driver.


Sorry for mixing these two patches together,

can I add your Reviewed-by tag when the patch is resubmitted for the 
next version?


Thx,

Yangtao

> >   2 files changed, 9 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/thermal/db8500_thermal.c 
> > b/drivers/thermal/db8500_thermal.c
> > index fca5c2c93bf9..0ef8fc2eb4a1 100644
> > --- a/drivers/thermal/db8500_thermal.c
> > +++ b/drivers/thermal/db8500_thermal.c
> > @@ -164,25 +164,21 @@ static int db8500_thermal_probe(struct 
> > platform_device *pdev)
> >       if (low_irq < 0)
> >           return low_irq;
> >   -    ret = devm_request_threaded_irq(dev, low_irq, NULL,
> > +    ret = devm_request_threaded_irq_probe(dev, low_irq, NULL,
> >           prcmu_low_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
> > -        "dbx500_temp_low", th);
> > -    if (ret < 0) {
> > -        dev_err(dev, "failed to allocate temp low irq\n");
> > +        "dbx500_temp_low", th, "temp low");
> > +    if (ret < 0)
> >           return ret;
> > -    }
> >         high_irq = platform_get_irq_byname(pdev, "IRQ_HOTMON_HIGH");
> >       if (high_irq < 0)
> >           return high_irq;
> >   -    ret = devm_request_threaded_irq(dev, high_irq, NULL,
> > +    ret = devm_request_threaded_irq_probe(dev, high_irq, NULL,
> >           prcmu_high_irq_handler, IRQF_NO_SUSPEND | IRQF_ONESHOT,
> > -        "dbx500_temp_high", th);
> > -    if (ret < 0) {
> > -        dev_err(dev, "failed to allocate temp high irq\n");
> > +        "dbx500_temp_high", th, "temp high");
> > +    if (ret < 0)
> >           return ret;
> > -    }
> >         /* register of thermal sensor and get info from DT */
> >       th->tz = devm_thermal_of_zone_register(dev, 0, th, &thdev_ops);
> > diff --git a/drivers/thermal/qcom/lmh.c b/drivers/thermal/qcom/lmh.c
> > index f6edb12ec004..48a14d7e8bf5 100644
> > --- a/drivers/thermal/qcom/lmh.c
> > +++ b/drivers/thermal/qcom/lmh.c
> > @@ -207,11 +207,10 @@ static int lmh_probe(struct platform_device *pdev)
> >         /* Disable the irq and let cpufreq enable it when ready to 
> > handle the interrupt */
> >       irq_set_status_flags(lmh_data->irq, IRQ_NOAUTOEN);
> > -    ret = devm_request_irq(dev, lmh_data->irq, lmh_handle_irq,
> > -                   IRQF_ONESHOT | IRQF_NO_SUSPEND,
> > -                   "lmh-irq", lmh_data);
> > +    ret = devm_request_irq_probe(dev, lmh_data->irq, lmh_handle_irq,
> > +                     IRQF_ONESHOT | IRQF_NO_SUSPEND,
> > +                     "lmh-irq", lmh_data, NULL);
> >       if (ret) {
> > -        dev_err(dev, "Error %d registering irq %x\n", ret, 
> > lmh_data->irq);
> >           irq_domain_remove(lmh_data->domain);
> >           return ret;
> >       }