This commit gets rid of the structure xdp_umem_props. It was there to
be able to break a dependency at one point, but this is no longer
needed. The values in the struct are instead stored directly in the
xdp_umem structure. This simplifies the xsk code as well as af_xdp
zero-copy drivers and as a bonus gets rid of one internal header file.
The i40e driver is also adapted to the new interface in this commit.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Currently, blkcg destruction relies on a sequence of events:
1. Destruction starts. blkcg_css_offline() is called and blkgs
release their reference to the blkcg. This immediately destroys
the cgwbs (writeback).
2. With blkgs giving up their reference, the blkcg ref count should
become zero and eventually call blkcg_css_free() which finally
frees the blkcg.
Jiufei Xue reported that there is a race between blkcg_bio_issue_check()
and cgroup_rmdir(). To remedy this, blkg destruction becomes contingent
on the completion of all writeback associated with the blkcg. A count of
the number of cgwbs is maintained and once that goes to zero, blkg
destruction can follow. This should prevent premature blkg destruction
related to writeback.
The new process for blkcg cleanup is as follows:
1. Destruction starts. blkcg_css_offline() is called which offlines
writeback. Blkg destruction is delayed on the cgwb_refcnt count to
avoid punting potentially large amounts of outstanding writeback
to root while maintaining any ongoing policies. Here, the base
cgwb_refcnt is put back.
2. When the cgwb_refcnt becomes zero, blkcg_destroy_blkgs() is called
and handles destruction of blkgs. This is where the css reference
held by each blkg is released.
3. Once the blkcg ref count goes to zero, blkcg_css_free() is called.
This finally frees the blkg.
It seems in the past blk-throttle didn't do the most understandable
things with taking data from a blkg while associating with current. So,
the simplification and unification of what blk-throttle is doing caused
this.
Fixes: 08e18eab0c ("block: add bi_blkg to the bio for cgroups")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Dennis Zhou <dennisszhou@gmail.com>
Cc: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This reverts commit 4c6994806f.
Destroying blkgs is tricky because of the nature of the relationship. A
blkg should go away when either a blkcg or a request_queue goes away.
However, blkg's pin the blkcg to ensure they remain valid. To break this
cycle, when a blkcg is offlined, blkgs put back their css ref. This
eventually lets css_free() get called which frees the blkcg.
The above commit (4c6994806f) breaks this order of events by trying to
destroy blkgs in css_free(). As the blkgs still hold references to the
blkcg, css_free() is never called.
The race between blkcg_bio_issue_check() and cgroup_rmdir() will be
addressed in the following patch by delaying destruction of a blkg until
all writeback associated with the blkcg has been finished.
Fixes: 4c6994806f ("blk-throttle: fix race between blkcg_bio_issue_check() and cgroup_rmdir()")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Dennis Zhou <dennisszhou@gmail.com>
Cc: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull arm64 fixes from Will Deacon:
"A few arm64 fixes came in this week, specifically fixing some nasty
truncation of return values from firmware calls and resolving a
VM_BUG_ON due to accessing uninitialised struct pages corresponding to
NOMAP pages.
Summary:
- Fix typos in SVE documentation
- Fix type-checking and implicit truncation for SMCCC calls
- Force CONFIG_HOLES_IN_ZONE=y so that SLAB doesn't fall over NOMAP
regions"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: mm: always enable CONFIG_HOLES_IN_ZONE
arm/arm64: smccc-1.1: Handle function result as parameters
arm/arm64: smccc-1.1: Make return values unsigned long
Documentation/arm64/sve: Couple of improvements and typos
Pull i2c fixes from Wolfram Sang:
- regression fixes for i801 and designware
- better API and leak fix for releasing DMA safe buffers
- better greppable strings for the bitbang algorithm
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: sh_mobile: fix leak when using DMA bounce buffer
i2c: sh_mobile: define start_ch() void as it only returns 0 anyhow
i2c: refactor function to release a DMA safe buffer
i2c: algos: bit: make the error messages grepable
i2c: designware: Re-init controllers with pm_disabled set on resume
i2c: i801: Allow ACPI AML access I/O ports not reserved for SMBus
For mem2mem devices we have to make sure that v4l2_m2m_try_schedule()
is called whenever a request is queued.
We do that by creating a vb2_m2m_request_queue() helper that should
be used instead of the 'normal' vb2_request_queue() helper. The m2m
helper function will call v4l2_m2m_try_schedule() as needed.
In addition we also avoid calling v4l2_m2m_try_schedule() when preparing
or queueing a buffer for a request since that is no longer needed.
Instead this helper function will do that when the request is actually
queued.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Set the first time a buffer from a request is queued to vb2
(uses_requests) or directly queued (uses_qbuf).
Cleared when the queue is canceled.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The generic vb2_request_validate helper function checks if
there are buffers in the request and if so, prepares (validates)
all objects in the request.
The generic vb2_request_queue helper function queues all buffer
objects in the validated request.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add a new helper function to tell if a request object is a buffer.
Add a new helper function that returns true if a media_request
contains at least one buffer.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This implements the V4L2 part of the request support. The main
change is that vb2_qbuf and vb2_prepare_buf now have a new
media_device pointer. This required changes to several drivers
that did not use the vb2_ioctl_qbuf/prepare_buf helper functions.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Buffers can now be prepared or queued for a request.
A buffer is unbound from the request at vb2_buffer_done time or
when the queue is cancelled.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
We need to initialize the request_fd field in struct vb2_v4l2_buffer
to -1 instead of the default of 0. So we need to add a new op that
is called when struct vb2_v4l2_buffer is allocated.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
When queuing buffers allow for passing the request that should
be associated with this buffer.
If V4L2_BUF_FLAG_REQUEST_FD is set, then request_fd is used as
the file descriptor.
If a buffer is stored in a request, but not yet queued to the
driver, then V4L2_BUF_FLAG_IN_REQUEST is set.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The PREPARED state becomes a problem with the request API: a buffer
could be PREPARED but dequeued, or PREPARED and in state IN_REQUEST.
PREPARED is really not a state as such, but more a property of the
buffer. So make new 'prepared' and 'synced' bools instead to remember
whether the buffer is prepared and/or synced or not.
V4L2_BUF_FLAG_PREPARED is only set if the buffer is both synced and
prepared and in the DEQUEUED state.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The userspace-provided plane data needs to be stored in
vb2_v4l2_buffer. Currently this information is applied by
__fill_vb2_buffer() which is called by the core prepare_buf
and qbuf functions, but when using requests these functions
aren't called yet since the buffer won't be prepared until
the media request is actually queued.
In the meantime this information has to be stored somewhere
and vb2_v4l2_buffer is a good place for it.
The __fill_vb2_buffer callback now just copies the relevant
information from vb2_v4l2_buffer into the planes array.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
If a driver needs to find/inspect the controls set in a request then
it can use these functions.
E.g. to check if a required control is set in a request use this in the
req_validate() implementation:
int res = -EINVAL;
hdl = v4l2_ctrl_request_hdl_find(req, parent_hdl);
if (hdl) {
if (v4l2_ctrl_request_hdl_ctrl_find(hdl, ctrl_id))
res = 0;
v4l2_ctrl_request_hdl_put(hdl);
}
return res;
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The v4l2_g/s_ext_ctrls functions now support control handlers that
represent requests.
The v4l2_ctrls_find_req_obj() function is responsible for finding the
request from the fd.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Integrate the request support. This adds the v4l2_ctrl_request_complete
and v4l2_ctrl_request_setup functions to complete a request and (as a
helper function) to apply a request to the hardware.
It takes care of queuing requests and correctly chaining control values
in the request queue.
Note that when a request is marked completed it will copy control values
to the internal request state. This can be optimized in the future since
this is sub-optimal when dealing with large compound and/or array controls.
For the initial 'stateless codec' use-case the current implementation is
sufficient.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Embed and initialize a media_request_object in struct v4l2_ctrl_handler.
Add a p_req field to struct v4l2_ctrl_ref that will store the
request value.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add a 'bool from_other_dev' argument: set to true if the two
handlers refer to different devices (e.g. it is true when
inheriting controls from a subdev into a main v4l2 bridge
driver).
This will be used later when implementing support for the
request API since we need to skip such controls.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add media_request_object_find to find a request object inside a
request based on ops and priv values.
Objects of the same type (vb2 buffer, control handler) will have
the same ops value. And objects that refer to the same 'parent'
object (e.g. the v4l2_ctrl_handler that has the current driver
state) will have the same priv value.
The caller has to call media_request_object_put() for the returned
object since this function increments the refcount.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add media_request_get_by_fd() to find a request based on the file
descriptor.
The caller has to call media_request_put() for the returned
request since this function increments the refcount.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add initial media request support:
1) Add MEDIA_IOC_REQUEST_ALLOC ioctl support to media-device.c
2) Add struct media_request to store request objects.
3) Add struct media_request_object to represent a request object.
4) Add MEDIA_REQUEST_IOC_QUEUE/REINIT ioctl support.
Basic lifecycle: the application allocates a request, adds
objects to it, queues the request, polls until it is completed
and can then read the final values of the objects at the time
of completion. When it closes the file descriptor the request
memory will be freed (actually, when the last user of that request
releases the request).
Drivers will bind an object to a request (the 'adds objects to it'
phase), when MEDIA_REQUEST_IOC_QUEUE is called the request is
validated (req_validate op), then queued (the req_queue op).
When done with an object it can either be unbound from the request
(e.g. when the driver has finished with a vb2 buffer) or marked as
completed (e.g. for controls associated with a buffer). When all
objects in the request are completed (or unbound), then the request
fd will signal an exception (poll).
Co-developed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Co-developed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Co-developed-by: Alexandre Courbot <acourbot@chromium.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Current ASoC is supporting snd_soc_dai_link_component for binding,
it is more useful than current legacy style.
Currently only codec is supporting it as multicodec (= codecs).
CPU will support multi style in the future.
We want to have it on Platform too in the future.
If all Codec/CPU/Platform are replaced into snd_soc_dai_link_component
style, we can remove legacy complex style.
This patch supports snd_soc_dai_link_component style
for simple-card-util for platform.
[current]
struct snd_soc_dai_link {
...
*cpu_name;
*cpu_of_node;
*cpu_dai_name;
*codec_name;
*codec_of_node;
*codec_dai_name;
*codecs;
num_codecs;
*platform_name;
*platform_of_node;
...
}
[in the future]
struct snd_soc_dai_link {
...
*cpus
num_cpus;
*codecs;
num_codecs;
*platform;
...
}
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Current struct snd_soc_dai_link is supporting multicodec,
and it is supporting legacy style of
codec_name
codec_of_node
code_dai_name
This is handled as single entry of multicodec.
We don't have multicpu support yet, but in the future we will.
In such case, we can use snd_soc_dai_link_component for both
cpu/codec. Then the code will be more simple and readble.
As next step, we want to use it for platform, too.
This patch adds snd_soc_dai_link_component style for platform.
We might have multiplatform support in the future, but we
don't know yet. To avoid un-known issue / complex code,
this patch supports just single-platform as 1st step.
If we could use snd_soc_dai_link_component for all CPU/Codec/Platform,
we will switch to new style, and remove legacy code.
This is prepare for it.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Current ASoC is supporting snd_soc_dai_link_component for binding,
it is more useful than current legacy style.
Currently only codec is supporting it as multicodec (= codecs).
CPU will support multi style in the future.
We want to have it on Platform too in the future.
If all Codec/CPU/Platform are replaced into snd_soc_dai_link_component
style, we can remove legacy complex style.
This patch supports snd_soc_dai_link_component style
for simple_card_utils for codec.
[current]
struct snd_soc_dai_link {
...
*cpu_name;
*cpu_of_node;
*cpu_dai_name;
*codec_name;
*codec_of_node;
*codec_dai_name;
*codecs;
num_codecs;
*platform_name;
*platform_of_node;
...
}
[in the future]
struct snd_soc_dai_link {
...
*cpus
num_cpus;
*codecs;
num_codecs;
*platform;
...
}
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Commit 1c892e38ce ("regulator: da9063: Handle less LDOs on DA9063L")
reordered the da9063_regulator_info[] array, but not the DA9063_ID_*
regulator ids and not the da9063_matches[] array, because ids are used
as indices in the array initializer. This mismatch between regulator id
and da9063_regulator_info[] array index causes the driver probe to fail
because constraints from DT are not applied to the correct regulator:
da9063 0-0058: Device detected (chip-ID: 0x61, var-ID: 0x50)
DA9063_BMEM: Bringing 900000uV into 3300000-3300000uV
DA9063_LDO9: Bringing 3300000uV into 2500000-2500000uV
DA9063_LDO1: Bringing 900000uV into 3300000-3300000uV
DA9063_LDO1: failed to apply 3300000-3300000uV constraint(-22)
This patch reorders the DA9063_ID_* as apparently intended, and with
them the entries in the da90630_matches[] array.
Fixes: 1c892e38ce ("regulator: da9063: Handle less LDOs on DA9063L")
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Marek Vasut <marek.vasut@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
A new helper function was introduced to facilitate the calculation
of time per frame value whenever we have access to the full
v4l2_dv_timings structure.
This should be used only for receivers and only when there is
enough accuracy in the measured pixel clock value as well as in
the horizontal/vertical values.
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add a new flag to UAPI for DV timings which, whenever set,
indicates that hardware can detect the difference between
regular FPS and 1000/1001 FPS.
This is specific to HDMI receivers. Also, it is only valid
when V4L2_DV_FL_CAN_REDUCE_FPS is set.
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In preparation to remove direct access to device_node.type, add
of_node_is_type() and of_node_get_device_type() helpers to check and
retrieve the device type.
Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Add device tree bindings for camera clock controller for
Qualcomm Technology Inc's SDM845 SoCs.
Signed-off-by: Amit Nischal <anischal@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Allocating a list_head structure that is almost never used, and, when
used, is used only during early boot (rcu_init() and earlier), is a bit
wasteful. This commit therefore eliminates that list_head in favor of
the one in the work_struct structure. This is safe because the work_struct
structure cannot be used until after rcu_init() returns.
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Event tracing is moving to SRCU in order to take advantage of the fact
that SRCU may be safely used from idle and even offline CPUs. However,
event tracing can invoke call_srcu() very early in the boot process,
even before workqueue_init_early() is invoked (let alone rcu_init()).
Therefore, call_srcu()'s attempts to queue work fail miserably.
This commit therefore detects this situation, and refrains from attempting
to queue work before rcu_init() time, but does everything else that it
would have done, and in addition, adds the srcu_struct to a global list.
The rcu_init() function now invokes a new srcu_init() function, which
is empty if CONFIG_SRCU=n. Otherwise, srcu_init() queues work for
each srcu_struct on the list. This all happens early enough in boot
that there is but a single CPU with interrupts disabled, which allows
synchronization to be dispensed with.
Of course, the queued work won't actually be invoked until after
workqueue_init() is invoked, which happens shortly after the scheduler
is up and running. This means that although call_srcu() may be invoked
any time after per-CPU variables have been set up, there is still a very
narrow window when synchronize_srcu() won't work, and this window
extends from the time that the scheduler starts until the time that
workqueue_init() returns. This can be fixed in a manner similar to
the fix for synchronize_rcu_expedited() and friends, but until someone
actually needs to use synchronize_srcu() during this window, this fix
is added churn for no benefit.
Finally, note that Tree SRCU's new srcu_init() function invokes
queue_work() rather than the queue_delayed_work() function that is
invoked post-boot. The reason is that queue_delayed_work() will (as you
would expect) post a timer, and timers have not yet been initialized.
So use of queue_work() avoids the complaints about use of uninitialized
spinlocks that would otherwise result. Besides, some delay is already
provide by the aforementioned fact that the queued work won't actually
be invoked until after the scheduler is up and running.
Requested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The rcu_dynticks_snap() function is defined in include/linux/rcutiny.h,
but is no longer used by Tiny RCU. This commit therefore removes it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit adds rcu_head_init() and rcu_head_after_call_rcu() functions
to help RCU users detect when another CPU has passed the specified
rcu_head structure and function to call_rcu(). The rcu_head_init()
should be invoked before making the structure visible to RCU readers,
and then the rcu_head_after_call_rcu() may be invoked from within
an RCU read-side critical section on an rcu_head structure that
was obtained during a traversal of the data structure in question.
The rcu_head_after_call_rcu() function will return true if the rcu_head
structure has already been passed (with the specified function) to
call_rcu(), otherwise it will return false.
If rcu_head_init() has not been invoked on the rcu_head structure
or if the rcu_head (AKA callback) has already been invoked, then
rcu_head_after_call_rcu() will do WARN_ON_ONCE().
Reported-by: NeilBrown <neilb@suse.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Apply neilb naming feedback. ]
The ->rcu_qs_ctr counter was intended to allow providing a lightweight
report of a quiescent state to all RCU flavors. But now that there is
only one flavor of RCU in any one running kernel, there is no point in
having this feature. This commit therefore removes the ->rcu_qs_ctr
field from the rcu_dynticks structure and the ->rcu_qs_ctr_snap field
from the rcu_data structure. This results in the "rqc" option to the
rcu_fqs trace event no longer being used, so this commit also removes the
"rqc" description from the header comment.
While in the neighborhood, this commit also causes the forward-progress
request .rcu_need_heavy_qs be set one jiffies_till_sched_qs interval
later in the grace period than the first setting of .rcu_urgent_qs.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Because rcu_barrier() is a one-line wrapper function for _rcu_barrier()
and because nothing else calls _rcu_barrier(), this commit inlines
_rcu_barrier() into rcu_barrier().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Now that rcu_all_qs() is used only in !PREEMPT builds, move it to
tree_plugin.h so that it is defined only in those builds. This in
turn means that rcu_momentary_dyntick_idle() is only used in !PREEMPT
builds, but it is simply marked __maybe_unused in order to keep it
near the rest of the dyntick-idle code.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Because RCU-tasks exists only in PREEMPT kernels and because RCU-sched
no longer exists in PREEMPT kernels, it is no longer necessary for the
rcu_note_voluntary_context_switch() macro to do anything for !PREEMPT
kernels. This commit therefore removes !PREEMPT-related code from
this macro, namely, the rcu_all_qs().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit saves a few lines by consolidating the RCU-sched function
definitions at the end of include/linux/rcupdate.h. This consolidation
also makes it easier to remove them all when the time comes.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit saves a few lines by consolidating the RCU-bh function
definitions at the end of include/linux/rcupdate.h. This consolidation
also makes it easier to remove them all when the time comes.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
