Re: [PATCH v8 00/29] Rework the trip points creation

[Daniel Lezcano]

On 03/10/2022 16:10, Marek Szyprowski wrote:
> Hi Daniel,
>
> On 03.10.2022 11:25, Daniel Lezcano wrote:
> > This work is the pre-requisite of handling correctly when the trip
> > point are crossed. For that we need to rework how the trip points are
> > declared and assigned to a thermal zone.
> >
> > Even if it appears to be a common sense to have the trip points being
> > ordered, this no guarantee neither documentation telling that is the
> > case.
> >
> > One solution could have been to create an ordered array of trips built
> > when registering the thermal zone by calling the different get_trip*
> > ops. However those ops receive a thermal zone pointer which is not
> > known as it is in the process of creating it.
> >
> > This cyclic dependency shows we have to rework how we manage the trip
> > points.
> >
> > Actually, all the trip points definition can be common to the backend
> > sensor drivers and we can factor out the thermal trip structure in all
> > of them.
> >
> > Then, as we register the thermal trips array, they will be available
> > in the thermal zone structure and a core function can return the trip
> > given its id.
> >
> > The get_trip_* ops won't be needed anymore and could be removed. The
> > resulting code will be another step forward to a self encapsulated
> > generic thermal framework.
> >
> > Most of the drivers can be converted more or less easily. This series
> > does a first round with most of the drivers. Some remain and will be
> > converted but with a smaller set of changes as the conversion is a bit
> > more complex.
> >
> > Changelog:
> > v8:
> > - Pretty oneline change and parenthesis removal (Rafael)
> > - Collected tags
> > v7:
> > - Added missing return 0 in the x86_pkg_temp driver
> > v6:
> > - Improved the code for the get_crit_temp() function as suggested by
> > Rafael
> > - Removed inner parenthesis in the set_trip_temp() function and invert the
> > conditions. Check the type of the trip point is unchanged
> > - Folded patch 4 with 1
> > - Add per thermal zone info message in the bang-bang governor
> > - Folded the fix for an uninitialized variable in
> > int340x_thermal_zone_add()
> > v5:
> > - Fixed a deadlock when calling thermal_zone_get_trip() while
> > handling the thermal zone lock
> > - Remove an extra line in the sysfs change
> > - Collected tags
> > v4:
> > - Remove extra lines on exynos changes as reported by Krzysztof Kozlowski
> > - Collected tags
> > v3:
> > - Reorg the series to be git-bisect safe
> > - Added the set_trip generic function
> > - Added the get_crit_temp generic function
> > - Removed more dead code in the thermal-of
> > - Fixed the exynos changelog
> > - Fixed the error check for the exynos drivers
> > - Collected tags
> > v2:
> > - Added missing EXPORT_SYMBOL_GPL() for thermal_zone_get_trip()
> > - Removed tab whitespace in the acerhdf driver
> > - Collected tags
> >
> > Cc: Raju Rangoju <rajur@xxxxxxxxxxx>
> > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> > Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
> > Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> > Cc: Paolo Abeni <pabeni@xxxxxxxxxx>
> > Cc: Peter Kaestle <peter@xxxxxxxx>
> > Cc: Hans de Goede <hdegoede@xxxxxxxxxx>
> > Cc: Mark Gross <markgross@xxxxxxxxxx>
> > Cc: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
> > Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> > Cc: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> > Cc: Amit Kucheria <amitk@xxxxxxxxxx>
> > Cc: Zhang Rui <rui.zhang@xxxxxxxxx>
> > Cc: Nicolas Saenz Julienne <nsaenz@xxxxxxxxxx>
> > Cc: Broadcom Kernel Team <bcm-kernel-feedback-list@xxxxxxxxxxxx>
> > Cc: Florian Fainelli <f.fainelli@xxxxxxxxx>
> > Cc: Ray Jui <rjui@xxxxxxxxxxxx>
> > Cc: Scott Branden <sbranden@xxxxxxxxxxxx>
> > Cc: Support Opensource <support.opensource@xxxxxxxxxxx>
> > Cc: Lukasz Luba <lukasz.luba@xxxxxxx>
> > Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> > Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> > Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> > Cc: Fabio Estevam <festevam@xxxxxxxxx>
> > Cc: NXP Linux Team <linux-imx@xxxxxxx>
> > Cc: Thara Gopinath <thara.gopinath@xxxxxxxxxx>
> > Cc: Andy Gross <agross@xxxxxxxxxx>
> > Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> > Cc: "Niklas Söderlund" <niklas.soderlund@xxxxxxxxxxxx>
> > Cc: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx>
> > Cc: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> > Cc: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
> > Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
> > Cc: Jonathan Hunter <jonathanh@xxxxxxxxxx>
> > Cc: Eduardo Valentin <edubezval@xxxxxxxxx>
> > Cc: Keerthy <j-keerthy@xxxxxx>
> > Cc: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
> > Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> > Cc: Antoine Tenart <atenart@xxxxxxxxxx>
> > Cc: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
> > Cc: Dmitry Osipenko <digetx@xxxxxxxxx>
> > Cc: netdev@xxxxxxxxxxxxxxx
> > Cc: linux-kernel@xxxxxxxxxxxxxxx
> > Cc: platform-driver-x86@xxxxxxxxxxxxxxx
> > Cc: linux-pm@xxxxxxxxxxxxxxx
> > Cc: linux-rpi-kernel@xxxxxxxxxxxxxxxxxxx
> > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> > Cc: linux-arm-msm@xxxxxxxxxxxxxxx
> > Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
> > Cc: linux-samsung-soc@xxxxxxxxxxxxxxx
> > Cc: linux-tegra@xxxxxxxxxxxxxxx
> > Cc: linux-omap@xxxxxxxxxxxxxxx
> >
> > Daniel Lezcano (29):
> > thermal/core: Add a generic thermal_zone_get_trip() function
> > thermal/sysfs: Always expose hysteresis attributes
> > thermal/core: Add a generic thermal_zone_set_trip() function
> > thermal/core/governors: Use thermal_zone_get_trip() instead of ops
> > functions
> > thermal/of: Use generic thermal_zone_get_trip() function
> > thermal/of: Remove unused functions
> > thermal/drivers/exynos: Use generic thermal_zone_get_trip() function
> > thermal/drivers/exynos: of_thermal_get_ntrips()
> > thermal/drivers/exynos: Replace of_thermal_is_trip_valid() by
> > thermal_zone_get_trip()
> > thermal/drivers/tegra: Use generic thermal_zone_get_trip() function
> > thermal/drivers/uniphier: Use generic thermal_zone_get_trip() function
> > thermal/drivers/hisi: Use generic thermal_zone_get_trip() function
> > thermal/drivers/qcom: Use generic thermal_zone_get_trip() function
> > thermal/drivers/armada: Use generic thermal_zone_get_trip() function
> > thermal/drivers/rcar_gen3: Use the generic function to get the number
> > of trips
> > thermal/of: Remove of_thermal_get_ntrips()
> > thermal/of: Remove of_thermal_is_trip_valid()
> > thermal/of: Remove of_thermal_set_trip_hyst()
> > thermal/of: Remove of_thermal_get_crit_temp()
> > thermal/drivers/st: Use generic trip points
> > thermal/drivers/imx: Use generic thermal_zone_get_trip() function
> > thermal/drivers/rcar: Use generic thermal_zone_get_trip() function
> > thermal/drivers/broadcom: Use generic thermal_zone_get_trip() function
> > thermal/drivers/da9062: Use generic thermal_zone_get_trip() function
> > thermal/drivers/ti: Remove unused macros ti_thermal_get_trip_value() /
> > ti_thermal_trip_is_valid()
> > thermal/drivers/acerhdf: Use generic thermal_zone_get_trip() function
> > thermal/drivers/cxgb4: Use generic thermal_zone_get_trip() function
> > thermal/intel/int340x: Replace parameter to simplify
> > thermal/drivers/intel: Use generic thermal_zone_get_trip() function
>
> I've tested this v8 patchset after fixing the issue with Exynos TMU with
> https://lore.kernel.org/all/20221003132943.1383065-1-daniel.lezcano@xxxxxxxxxx/
> patch and I got the following lockdep warning on all Exynos-based boards:
>
> ======================================================
> WARNING: possible circular locking dependency detected
> 6.0.0-rc1-00083-ge5c9d117223e #12945 Not tainted
> ------------------------------------------------------
> swapper/0/1 is trying to acquire lock:
> c1ce66b0 (&data->lock#2){+.+.}-{3:3}, at: exynos_get_temp+0x3c/0xc8
>
> but task is already holding lock:
> c2979b94 (&tz->lock){+.+.}-{3:3}, at:
> thermal_zone_device_update.part.0+0x3c/0x528
>
> which lock already depends on the new lock.

Investigating ...



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