Commit Graph

19 Commits

Author SHA1 Message Date
Tejun Heo
44d69dd9ad greybus: Use alloc_ordered_workqueue() to create ordered workqueues
BACKGROUND
==========

When multiple work items are queued to a workqueue, their execution order
doesn't match the queueing order. They may get executed in any order and
simultaneously. When fully serialized execution - one by one in the queueing
order - is needed, an ordered workqueue should be used which can be created
with alloc_ordered_workqueue().

However, alloc_ordered_workqueue() was a later addition. Before it, an
ordered workqueue could be obtained by creating an UNBOUND workqueue with
@max_active==1. This originally was an implementation side-effect which was
broken by 4c16bd327c ("workqueue: restore WQ_UNBOUND/max_active==1 to be
ordered"). Because there were users that depended on the ordered execution,
5c0338c687 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered")
made workqueue allocation path to implicitly promote UNBOUND workqueues w/
@max_active==1 to ordered workqueues.

While this has worked okay, overloading the UNBOUND allocation interface
this way creates other issues. It's difficult to tell whether a given
workqueue actually needs to be ordered and users that legitimately want a
min concurrency level wq unexpectedly gets an ordered one instead. With
planned UNBOUND workqueue updates to improve execution locality and more
prevalence of chiplet designs which can benefit from such improvements, this
isn't a state we wanna be in forever.

This patch series audits all callsites that create an UNBOUND workqueue w/
@max_active==1 and converts them to alloc_ordered_workqueue() as necessary.

WHAT TO LOOK FOR
================

The conversions are from

  alloc_workqueue(WQ_UNBOUND | flags, 1, args..)

to 

  alloc_ordered_workqueue(flags, args...)

which don't cause any functional changes. If you know that fully ordered
execution is not ncessary, please let me know. I'll drop the conversion and
instead add a comment noting the fact to reduce confusion while conversion
is in progress.

If you aren't fully sure, it's completely fine to let the conversion
through. The behavior will stay exactly the same and we can always
reconsider later.

As there are follow-up workqueue core changes, I'd really appreciate if the
patch can be routed through the workqueue tree w/ your acks. Thanks.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Alex Elder <elder@kernel.org>
Cc: greybus-dev@lists.linaro.org
2023-05-08 13:52:27 -10:00
Greg Kroah-Hartman
2a81ada32f driver core: make struct bus_type.uevent() take a const *
The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.

Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-27 13:45:52 +01:00
Christophe JAILLET
0d4a030b3d greybus: svc: Use kstrtobool() instead of strtobool()
strtobool() is the same as kstrtobool().
However, the latter is more used within the kernel.

In order to remove strtobool() and slightly simplify kstrtox.h, switch to
the other function name.

While at it, include the corresponding header file (<linux/kstrtox.h>)

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/ebf1e6988a53a455990230a37cf759ee542ea7ec.1667336095.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10 19:03:58 +01:00
Johan Hovold
a74e7263b5 greybus: svc: clean up link configuration hack at hello
Commit ee2f2074fd ("greybus: svc: reconfig APBridgeA-Switch link to
handle required load") added a temporary hack which reconfigures the
link at HELLO by abusing the deferred request processing mechanism.

Restructure the HELLO request processing so that the link-configuration
work is queued before creating the debugfs files and add a comment
explaining why it's there.

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20220202113347.1288-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-04 15:27:44 +01:00
Johan Hovold
5f648e00f5 greybus: svc: clean up hello error path
While currently safe, it is unnecessary (and confusing) to try to
destroy the watchdog when watchdog creation fails.

Change the corresponding error path to only deregister the svc.

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20220202113347.1288-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-04 15:27:44 +01:00
Dan Carpenter
5f8583a3b7 greybus: svc: fix an error handling bug in gb_svc_hello()
Cleanup if gb_svc_queue_deferred_request() fails.

Link: https://lore.kernel.org/r/20220202072016.GA6748@kili
Fixes: ee2f2074fd ("greybus: svc: reconfig APBridgeA-Switch link to handle required load")
Cc: stable@vger.kernel.org      # 4.9
[johan: fix commit summary prefix and rename label ]
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20220202113347.1288-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-04 15:27:44 +01:00
Jason Wang
909c648e03 greybus: es2: fix typo in a comment
The double `for' in the comment in line 81 is repeated. Remove one
of them from the comment.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Link: https://lore.kernel.org/r/20211212031657.41169-1-wangborong@cdjrlc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-21 10:13:26 +01:00
Randy Dunlap
39d2a7898d greybus: es2: fix kernel-doc warnings
Fix these kernel-doc complaints:

../drivers/greybus/es2.c:79: warning: bad line:
../drivers/greybus/es2.c💯 warning: cannot understand function prototype: 'struct es2_ap_dev '
es2.c:126: warning: Function parameter or member 'cdsi1_in_use' not described in 'es2_ap_dev'

Cc: Johan Hovold <johan@kernel.org>
Cc: Alex Elder <elder@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: greybus-dev@lists.linaro.org (moderated for non-subscribers)
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210415054338.2223-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-16 07:26:50 +02:00
Rasmus Villemoes
012ac583aa greybus: remove stray nul byte in apb_log_enable_read output
Including a nul byte in the otherwise human-readable ascii output
from this debugfs file is probably not intended.

Acked-by: Alex Elder <elder@linaro.org>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20210326152254.733066-1-linux@rasmusvillemoes.dk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-02 16:24:56 +02:00
Johan Hovold
e4240253ac greybus: es2: drop short control-transfer checks
There's no need to check for short USB control transfers when sending
data using so remove the redundant sanity checks.

Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210118144629.25533-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-26 19:20:11 +01:00
Tom Rix
4c5a6a7b71 greybus: remove h from printk format specifier
See Documentation/core-api/printk-formats.rst.
h should no longer be used in the format specifier for printk.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20201215145306.1901598-1-trix@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-05 15:18:23 +01:00
Wang Qing
947bece14b drivers/greybus: Use kobj_to_dev()
Use kobj_to_dev() instead of container_of()

Signed-off-by: Wang Qing <wangqing@vivo.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/1597289690-22857-1-git-send-email-wangqing@vivo.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04 18:06:01 +02:00
Gustavo A. R. Silva
37b8b73f64 greybus: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1].

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200727183258.GA28571@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-29 16:58:08 +02:00
Masahiro Yamada
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Gustavo A. R. Silva
84c1e51d7d greybus: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200507185318.GA14393@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-13 13:59:13 +02:00
Zenyu Sy
7aa428dfc8 greybus: fix typos in GREYBUS/GREYBUS_ES2 help text
Fix typos ("an" -> "a", "chose" -> "choose") in Kconfig

Signed-off-by: Zenyu Sy <zenyu@tuta.io>
Link: https://lore.kernel.org/r/20200426060048.14019-1-zenyu@tuta.io
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29 12:05:45 +02:00
Denis Efremov
32a738704d greybus: remove excessive check in gb_connection_hd_cport_quiesce()
Function pointer "hd->driver->cport_quiesce" is already checked
at the beginning of gb_connection_hd_cport_quiesce(). Thus, the
second check can be removed.

Signed-off-by: Denis Efremov <efremov@linux.com>
Acked-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20190925213656.8950-1-efremov@linux.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-10 15:24:19 +02:00
Greg Kroah-Hartman
b81beec9cb staging: greybus: move es2 to drivers/greybus/
The es2 Greybus host controller has long been stable, so move it out of
drivers/staging/ to drivers/greybus/

Cc: Johan Hovold <johan@kernel.org>
Cc: greybus-dev@lists.linaro.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Alex Elder <elder@kernel.org>
Link: https://lore.kernel.org/r/20190825055429.18547-10-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-27 19:03:08 +02:00
Greg Kroah-Hartman
8465def499 staging: greybus: move the greybus core to drivers/greybus
The Greybus core code has been stable for a long time, and has been
shipping for many years in millions of phones.  With the advent of a
recent Google Summer of Code project, and a number of new devices in the
works from various companies, it is time to get the core greybus code
out of staging as it really is going to be with us for a while.

Cc: Johan Hovold <johan@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: greybus-dev@lists.linaro.org
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Alex Elder <elder@kernel.org>
Link: https://lore.kernel.org/r/20190825055429.18547-9-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-27 19:03:04 +02:00