[PATCH v3 0/5] introduce devm_request_threaded_irq_emsg()

[Yangtao Li]

+cc u.kleine-koenig at pengutronix.de, krzysztof.kozlowski at linaro.org

On 2023/7/3 17:04, Yangtao Li wrote:
> There are more than 700 calls to the devm_request_threaded_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 1000 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 add devm_request_threaded_irq_emsg(), 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.
>
> Yangtao Li (5):
>    genirq/devres: Add devm_request_threaded_irq_emsg()
>    thermal/drivers/armada: convert to use
>      devm_request_threaded_irq_emsg()
>    thermal/drivers/brcmstb_thermal: convert to use
>      devm_request_threaded_irq_emsg()
>    thermal/drivers/db8500: convert to use
>      devm_request_threaded_irq_emsg()
>    thermal/drivers/mediatek/lvts_thermal: convert to use
>      devm_request_threaded_irq_emsg()
>
>   drivers/thermal/armada_thermal.c           | 13 +++----
>   drivers/thermal/broadcom/brcmstb_thermal.c | 12 +++----
>   drivers/thermal/db8500_thermal.c           | 16 ++++-----
>   drivers/thermal/mediatek/lvts_thermal.c    |  6 ++--
>   include/linux/interrupt.h                  |  6 ++++
>   kernel/irq/devres.c                        | 42 ++++++++++++++++++++++
>   6 files changed, 67 insertions(+), 28 deletions(-)
>