Add auxiliary driver to support StarFive JH7110 system
and always-on resets.
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Add driver for the StarFive JH7110 always-on clock controller
and register an auxiliary device for always-on reset controller
which is named as "rst-aon".
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Co-developed-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Add driver for the StarFive JH7110 system clock controller and
register an auxiliary device for system reset controller which
is named as "rst-sys".
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Co-developed-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
We currently use 64bit I/O on the 32bit registers. This works because
there are an even number of assert and status registers, so they're only
ever accessed in pairs on 64bit boundaries.
There are however other reset controllers for audio and video on the
JH7100 SoC with only one status register that isn't 64bit aligned so
64bit I/O results in an unaligned access exception.
Switch to 32bit I/O in preparation for supporting these resets too.
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
For the common code will be shared with the StarFive JH7110 SoC.
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Extract the common JH71X0 reset code for reusing them to
support JH7110 SoC.
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
The StarFive JH7100 SoC has additional reset controllers for audio and
video, but the registers follow the same structure. On the JH7110 the
reset registers don't get their own memory range, but instead follow the
clock control registers. The registers still follow the same structure
though, so let's factor out the common code to handle all these cases.
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
This moves the StarFive JH7100 reset driver to a new subdirectory in
preparation for adding more StarFive reset drivers.
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Using ARCH_FOO symbol is preferred than SOC_FOO.
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Rename some variables from "jh7100" or "JH7100" to "jh71x0"
or "JH71X0".
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Rename clk-starfive-jh7100.h to clk-starfive-jh71x0.h for making
the code to be common.
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
The clock control registers on the StarFive JH7100 and JH7110 work
identically, so factor out the code then drivers for the two SoCs
can share it without depending on each other. No functional change.
Tested-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Using ARCH_FOO symbol is preferred than SOC_FOO.
Set obj-y for starfive/ in Makefile, so the StarFive drivers
can be compiled with COMPILE_TEST=y but ARCH_STARFIVE=n.
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Add bindings for the always-on clock and reset generator (AONCRG) on the
JH7110 RISC-V SoC by StarFive Ltd.
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Add bindings for the system clock and reset generator (SYSCRG) on the
JH7110 RISC-V SoC by StarFive Ltd.
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Hal Feng <hal.feng@starfivetech.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Add blank lines after declarations to adhere to the Linux kernel
coding-style. Check reported by checkpatch.pl
"CHECK: Please use a blank line after function/struct/union/enum
declarations"
Signed-off-by: Sumitra Sharma <sumitraartsy@gmail.com>
Link: https://lore.kernel.org/r/20230405063003.GA218972@sumitra.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel coding-style suggests to not use mixed-case names. Fix
checkpatch issue by changing the variable name from camel case to snake
case.
Signed-off-by: Khadija Kamran <kamrankhadijadj@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/d29ff5db6f19d79ee762a835db88155bee2aefba.1680445545.git.kamrankhadijadj@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel coding-style suggests to not use mixed-case names. Fix
checkpatch issue by changing the variable name from camel case to snake
case.
Signed-off-by: Khadija Kamran <kamrankhadijadj@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/7166160c0face9e32dbb28c44727eb8856173f0a.1680445545.git.kamrankhadijadj@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel coding-style suggests to not use mixed-case names. Fix
checkpatch issue by changing the variable name from camel case to snake
case.
Signed-off-by: Khadija Kamran <kamrankhadijadj@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/ebfd9c40400eac872b9af2a5120b0829ff71e077.1680445545.git.kamrankhadijadj@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove extra blank lines as suggested by the Linux kernel coding-style.
These issues were reported by checkpatch.
"CHECK: Please don't use multiple blank lines"
Signed-off-by: Khadija Kamran <kamrankhadijadj@gmail.com>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/283265f6a5ff938f8425e14af86cee9e2da36318.1680445545.git.kamrankhadijadj@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
customer_id is initialize to zero. Changing customer_id to RT_CID_DEFAULT
will not change customer_id as it is already zero. default and
EEPROM_CID_WHQL contain only a break. Remove useless code lines to
increase readability.
Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/58df9db5da84991206266e739b2a12c893d1be8e.1680427945.git.philipp.g.hortmann@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
customer_id is initialize to zero. Changing customer_id to
RT_CID_819x_CAMEO, RT_CID_819x_RUNTOP, RT_CID_Nettronix or RT_CID_PRONET
would not change the program execution as there is no equation for
RT_CID_819x_CAMEO, RT_CID_819x_RUNTOP, RT_CID_Nettronix or RT_CID_PRONET.
Remove useless code lines to increase readability.
Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/b546933897acc20a6ac5be2bd5ef5ad979599c66.1680427945.git.philipp.g.hortmann@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
customer_id is initialize to zero. Changing customer_id to RT_CID_DLINK
would not change the program execution as there is no equation for
RT_CID_DLINK. Remove useless code lines to increase readability.
Signed-off-by: Philipp Hortmann <philipp.g.hortmann@gmail.com>
Link: https://lore.kernel.org/r/e4ecef11015c32c9909cd07e0939c4de53fd501a.1680427945.git.philipp.g.hortmann@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use tabs to indent code and spaces to align in order to make the code
consistent and easier to read.
Signed-off-by: Daniel Watson <ozzloy@gmail.com>
Link: https://lore.kernel.org/r/ZCdmCBIdabBGqm11@trent-reznor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The file staging/vme_user/Kconfig is only included by the top-level
staging/Kconfig if STAGING is enabled. So, there is no need to mention the
dependency on STAGING within the vme_user Kconfig file. Further, the config
VME_USER is already within the "if VME_BUS" block, so there is no need to
mention the dependency on VME_BUS.
Clean up these duplications of dependencies. No semantic change.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Link: https://lore.kernel.org/r/20230329074342.27595-1-lukas.bulwahn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Building with W=1 leads to the following dtc warning:
arch/arm/boot/dts/imx6ull-colibri.dtsi:36.9-46.5: Warning (graph_child_address): /connector/ports: graph node has single child node 'port@0', #address-cells/#size-cells are not necessary
Since a single port is used, 'ports' can be removed, as well as the
unnecessary #address-cells/#size-cells.
Fixes: bd5880e109 ("ARM: dts: colibri-imx6ull: Enable dual-role switching")
Signed-off-by: Fabio Estevam <festevam@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Building with W=1 leads to the following dtc warning:
arch/arm/boot/dts/imx7d-remarkable2.dts:319.19-335.4: Warning (avoid_unnecessary_addr_size): /soc/bus@30800000/i2c@30a50000/pmic@62: unnecessary #address-cells/#size-cells without "ranges" or child "reg" property
Remove unnecessary #address-cells/#size-cells to fix it.
Fixes: 9076cbaa77 ("ARM: dts: imx7d-remarkable2: Enable silergy,sy7636a")
Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Alistair Francis <alistair@alistair23.me>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The property should be off-on-delay-us, not off-on-delay
Fixes: a39ed23bdf ("arm64: dts: freescale: add initial support for verdin imx8m plus")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The property should be off-on-delay-us, not off-on-delay
Fixes: 6a57f224f7 ("arm64: dts: freescale: add initial support for verdin imx8m mini")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Single-argument kvfree_rcu() usage is being deprecated [1] [2]. However,
till all users are converted, we would like to introduce checkpatch
errors for new patches submitted.
This patch adds support for the same. Tested with a trial patch.
For now, we are only considering usages that don't have compound
nesting, for example ignore: kvfree_rcu( (rcu_head_obj), rcu_head_name).
This is sufficient as such usages are unlikely.
Once all users are converted and we remove the old API, we can also revert this
checkpatch patch then.
[1] https://lore.kernel.org/rcu/CAEXW_YRhHaVuq+5f+VgCZM=SF+9xO+QXaxe0yE7oA9iCXK-XPg@mail.gmail.com/
[2] https://lore.kernel.org/rcu/CAEXW_YSY=q2_uaE2qo4XSGjzs4+C102YMVJ7kWwuT5LGmJGGew@mail.gmail.com/
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The k[v]free_rcu() macro's single-argument form is deprecated.
Therefore switch to the new k[v]free_rcu_mightsleep() variant. The goal
is to avoid accidental use of the single-argument forms, which can
introduce functionality bugs in atomic contexts and latency bugs in
non-atomic contexts.
The callers are holding a mutex so the context allows blocking. Hence
using the API with a single argument will be fine, but use its new name.
There is no functionality change with this patch.
Fixes: 57588c7117 ("mac802154: Handle passive scanning")
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kfree_rcu() and kvfree_rcu() macros' single-argument forms are
deprecated. Therefore switch to the new kfree_rcu_mightsleep() and
kvfree_rcu_mightsleep() variants. The goal is to avoid accidental use
of the single-argument forms, which can introduce functionality bugs in
atomic contexts and latency bugs in non-atomic contexts.
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kfree_rcu() and kvfree_rcu() macros' single-argument forms are
deprecated. Therefore switch to the new kfree_rcu_mightsleep() and
kvfree_rcu_mightsleep() variants. The goal is to avoid accidental use
of the single-argument forms, which can introduce functionality bugs in
atomic contexts and latency bugs in non-atomic contexts.
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Lukas Czerner <lczerner@redhat.com>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kfree_rcu() and kvfree_rcu() macros' single-argument forms are
deprecated. Therefore switch to the new kfree_rcu_mightsleep() and
kvfree_rcu_mightsleep() variants. The goal is to avoid accidental use
of the single-argument forms, which can introduce functionality bugs in
atomic contexts and latency bugs in non-atomic contexts.
Cc: Ariel Levkovich <lariel@nvidia.com>
Cc: Saeed Mahameed <saeedm@nvidia.com>
Cc: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kfree_rcu() and kvfree_rcu() macros' single-argument forms are
deprecated. Therefore switch to the new kfree_rcu_mightsleep() and
kvfree_rcu_mightsleep() variants. The goal is to avoid accidental use
of the single-argument forms, which can introduce functionality bugs in
atomic contexts and latency bugs in non-atomic contexts.
Acked-by: Jakub Kicinski <kuba@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kvfree_rcu() macro's single-argument form is deprecated. Therefore
switch to the new kvfree_rcu_mightsleep() variant. The goal is to
avoid accidental use of the single-argument forms, which can introduce
functionality bugs in atomic contexts and latency bugs in non-atomic
contexts.
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kvfree_rcu() macro's single-argument form is deprecated. Therefore
switch to the new kvfree_rcu_mightsleep() variant. The goal is to
avoid accidental use of the single-argument forms, which can introduce
functionality bugs in atomic contexts and latency bugs in non-atomic
contexts.
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kvfree_rcu() macro's single-argument form is deprecated. Therefore
switch to the new kvfree_rcu_mightsleep() variant. The goal is to
avoid accidental use of the single-argument forms, which can introduce
functionality bugs in atomic contexts and latency bugs in non-atomic
contexts.
Cc: Bryan Tan <bryantan@vmware.com>
Cc: Vishnu Dasa <vdasa@vmware.com>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The kvfree_rcu() macro's single-argument form is deprecated. Therefore
switch to the new kvfree_rcu_mightsleep() variant. The goal is to
avoid accidental use of the single-argument forms, which can introduce
functionality bugs in atomic contexts and latency bugs in non-atomic
contexts.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Begrudgingly-acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
For kernels built with CONFIG_PREEMPT_RCU=y, the following scenario can
result in a NULL-pointer dereference:
CPU1 CPU2
rcu_preempt_deferred_qs_irqrestore rcu_print_task_exp_stall
if (special.b.blocked) READ_ONCE(rnp->exp_tasks) != NULL
raw_spin_lock_rcu_node
np = rcu_next_node_entry(t, rnp)
if (&t->rcu_node_entry == rnp->exp_tasks)
WRITE_ONCE(rnp->exp_tasks, np)
....
raw_spin_unlock_irqrestore_rcu_node
raw_spin_lock_irqsave_rcu_node
t = list_entry(rnp->exp_tasks->prev,
struct task_struct, rcu_node_entry)
(if rnp->exp_tasks is NULL, this
will dereference a NULL pointer)
The problem is that CPU2 accesses the rcu_node structure's->exp_tasks
field without holding the rcu_node structure's ->lock and CPU2 did
not observe CPU1's change to rcu_node structure's ->exp_tasks in time.
Therefore, if CPU1 sets rcu_node structure's->exp_tasks pointer to NULL,
then CPU2 might dereference that NULL pointer.
This commit therefore holds the rcu_node structure's ->lock while
accessing that structure's->exp_tasks field.
[ paulmck: Apply Frederic Weisbecker feedback. ]
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The call to synchronize_srcu() from rcu_tasks_postscan() can be stalled
by a task getting stuck in do_exit() between that function's calls to
exit_tasks_rcu_start() and exit_tasks_rcu_finish(). To ease diagnosis
of this situation, print a stall warning message every rcu_task_stall_info
period when rcu_tasks_postscan() is stalled.
[ paulmck: Adjust to handle CONFIG_SMP=n. ]
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reported-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/rcu/20230111212736.GA1062057@paulmck-ThinkPad-P17-Gen-1/
Signed-off-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
According to the commit log of the patch that added it to the kernel,
start_poll_synchronize_rcu_expedited() can be invoked very early, as
in long before rcu_init() has been invoked. But before rcu_init(),
the rcu_data structure's ->mynode field has not yet been initialized.
This means that the start_poll_synchronize_rcu_expedited() function's
attempt to set the CPU's leaf rcu_node structure's ->exp_seq_poll_rq
field will result in a segmentation fault.
This commit therefore causes start_poll_synchronize_rcu_expedited() to
set ->exp_seq_poll_rq only after rcu_init() has initialized all CPUs'
rcu_data structures' ->mynode fields. It also removes the check from
the rcu_init() function so that start_poll_synchronize_rcu_expedited(
is unconditionally invoked. Yes, this might result in an unnecessary
boot-time grace period, but this is down in the noise.
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The rcu_accelerate_cbs() function is invoked by rcu_report_qs_rdp()
only if there is a grace period in progress that is still blocked
by at least one CPU on this rcu_node structure. This means that
rcu_accelerate_cbs() should never return the value true, and thus that
this function should never set the needwake variable and in turn never
invoke rcu_gp_kthread_wake().
This commit therefore removes the needwake variable and the invocation
of rcu_gp_kthread_wake() in favor of a WARN_ON_ONCE() on the call to
rcu_accelerate_cbs(). The purpose of this new WARN_ON_ONCE() is to
detect situations where the system's opinion differs from ours.
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
