All of lore.kernel.org
 help / color / mirror / Atom feed
From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
To: stefan.wahren@i2se.com, eric@anholt.net, dave.stevenson@raspberrypi.org
Cc: nsaenzjulienne@suse.de, linux-rpi-kernel@lists.infradead.org,
	gregkh@linuxfoundation.org, linux-arm-kernel@lists.infradead.org,
	devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org
Subject: [PATCH RFC 18/18] staging: vchiq: add more tasks to the TODO list
Date: Fri, 26 Oct 2018 15:48:13 +0200	[thread overview]
Message-ID: <20181026134813.7775-19-nsaenzjulienne@suse.de> (raw)
In-Reply-To: <20181026134813.7775-1-nsaenzjulienne@suse.de>

The more the better.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---
 .../staging/vc04_services/interface/vchi/TODO | 46 ++++++++++++++++++-
 1 file changed, 44 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/vc04_services/interface/vchi/TODO b/drivers/staging/vc04_services/interface/vchi/TODO
index 0b3ec75ff627..bf2135826431 100644
--- a/drivers/staging/vc04_services/interface/vchi/TODO
+++ b/drivers/staging/vc04_services/interface/vchi/TODO
@@ -27,8 +27,8 @@ unused.
 3) Make driver more portable
 
 Building this driver with arm/multi_v7_defconfig or arm64/defconfig
-leads to data corruption during the following command: 
-  
+leads to data corruption during the following command:
+
   vchiq_test -f 1
 
 This should be fixed.
@@ -49,3 +49,45 @@ such as dev_info, dev_dbg, and friends.
 
 A short top-down description of this driver's architecture (function of
 kthreads, userspace, limitations) could be very helpful for reviewers.
+
+7) Review and comment memory barriers
+
+There is a heavy use of memory barriers in this driver, it would be very
+beneficial to go over all of them and, if correct, comment on their merits.
+Extra points to whomever confidently reviews the remote_event_*() family of
+functions.
+
+8) Get rid of custom function return values
+
+Most functions use a custom set of return values, we should force proper Linux
+error numbers. Special care is needed for VCHIQ_RETRY.
+
+9) Reformat core code with more sane indentations
+
+The code follows the 80 characters limitation yet tends to go 3 or 4 levels of
+indentation deep making it very unpleasant to read. This is specially relevant
+in the character driver ioctl code and in the core thread functions.
+
+10) Reorganize file structure: Move char driver to it's own file and join both
+platform files
+
+The cdev is defined alongside with the platform code in vchiq_arm.c. It would
+be nice to completely decouple it from the actual core code. For instance to be
+able to use bcm2835-audio without having /dev/vchiq created. One could argue
+it's better for security reasons or general cleanliness. It could even be
+interesting to create two different kernel modules, something the likes of
+vchiq-core.ko and vchiq-dev.ko. This would also ease the upstreaming process.
+
+The code in vchiq_bcm2835_arm.c should fit in the generic platform file.
+
+12) Get rid of all the struct typedefs
+
+Most structs are typedefd, it's not encouraged in the kernel.
+
+13) Get rid of all non essential global structures and create a proper per
+device structure
+
+The first thing one generally sees in a probe function is a memory allocation
+for all the device specific data. This structure is then passed all over the
+driver. This is good practice since it makes the driver work regardless of the
+number of devices probed.
-- 
2.19.1


WARNING: multiple messages have this Message-ID
From: nsaenzjulienne@suse.de (Nicolas Saenz Julienne)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH RFC 18/18] staging: vchiq: add more tasks to the TODO list
Date: Fri, 26 Oct 2018 15:48:13 +0200	[thread overview]
Message-ID: <20181026134813.7775-19-nsaenzjulienne@suse.de> (raw)
In-Reply-To: <20181026134813.7775-1-nsaenzjulienne@suse.de>

The more the better.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---
 .../staging/vc04_services/interface/vchi/TODO | 46 ++++++++++++++++++-
 1 file changed, 44 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/vc04_services/interface/vchi/TODO b/drivers/staging/vc04_services/interface/vchi/TODO
index 0b3ec75ff627..bf2135826431 100644
--- a/drivers/staging/vc04_services/interface/vchi/TODO
+++ b/drivers/staging/vc04_services/interface/vchi/TODO
@@ -27,8 +27,8 @@ unused.
 3) Make driver more portable
 
 Building this driver with arm/multi_v7_defconfig or arm64/defconfig
-leads to data corruption during the following command: 
-  
+leads to data corruption during the following command:
+
   vchiq_test -f 1
 
 This should be fixed.
@@ -49,3 +49,45 @@ such as dev_info, dev_dbg, and friends.
 
 A short top-down description of this driver's architecture (function of
 kthreads, userspace, limitations) could be very helpful for reviewers.
+
+7) Review and comment memory barriers
+
+There is a heavy use of memory barriers in this driver, it would be very
+beneficial to go over all of them and, if correct, comment on their merits.
+Extra points to whomever confidently reviews the remote_event_*() family of
+functions.
+
+8) Get rid of custom function return values
+
+Most functions use a custom set of return values, we should force proper Linux
+error numbers. Special care is needed for VCHIQ_RETRY.
+
+9) Reformat core code with more sane indentations
+
+The code follows the 80 characters limitation yet tends to go 3 or 4 levels of
+indentation deep making it very unpleasant to read. This is specially relevant
+in the character driver ioctl code and in the core thread functions.
+
+10) Reorganize file structure: Move char driver to it's own file and join both
+platform files
+
+The cdev is defined alongside with the platform code in vchiq_arm.c. It would
+be nice to completely decouple it from the actual core code. For instance to be
+able to use bcm2835-audio without having /dev/vchiq created. One could argue
+it's better for security reasons or general cleanliness. It could even be
+interesting to create two different kernel modules, something the likes of
+vchiq-core.ko and vchiq-dev.ko. This would also ease the upstreaming process.
+
+The code in vchiq_bcm2835_arm.c should fit in the generic platform file.
+
+12) Get rid of all the struct typedefs
+
+Most structs are typedefd, it's not encouraged in the kernel.
+
+13) Get rid of all non essential global structures and create a proper per
+device structure
+
+The first thing one generally sees in a probe function is a memory allocation
+for all the device specific data. This structure is then passed all over the
+driver. This is good practice since it makes the driver work regardless of the
+number of devices probed.
-- 
2.19.1

  parent reply	other threads:[~2018-10-26 13:48 UTC|newest]

Thread overview: 54+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-26 13:47 [PATCH RFC 00/18] staging: vchiq: remove dead code & misc fixes Nicolas Saenz Julienne
2018-10-26 13:47 ` Nicolas Saenz Julienne
2018-10-26 13:47 ` [PATCH RFC 01/18] staging: vchiq_core: rework vchiq_get_config Nicolas Saenz Julienne
2018-10-26 13:47   ` Nicolas Saenz Julienne
2018-10-26 13:47 ` [PATCH RFC 02/18] staging: vchiq_arm: rework close/remove_service IOCTLS Nicolas Saenz Julienne
2018-10-26 13:47   ` Nicolas Saenz Julienne
2018-10-26 13:47 ` [PATCH RFC 03/18] staging: vchiq_shim: delete vchi_service_create Nicolas Saenz Julienne
2018-10-26 13:47   ` Nicolas Saenz Julienne
2018-10-26 13:47 ` [PATCH RFC 04/18] stagning: vchiq_arm: use list_for_each_entry when accessing bulk_waiter_list Nicolas Saenz Julienne
2018-10-26 13:47   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 05/18] staging: vchiq_arm: get rid of vchi_mh.h Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 06/18] staging: vchiq_arm: rework vchiq_ioc_copy_element_data Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 07/18] staging: vchiq-core: get rid of is_master distinction Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 08/18] staging: vchiq_core: remove unnecessary safety checks in vchiq_init_state Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 09/18] staging: vchiq_core: do not initialize semaphores twice Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-28 20:45   ` Stefan Wahren
2018-10-28 20:45     ` Stefan Wahren
2018-11-06 15:41     ` Nicolas Saenz Julienne
2018-11-06 15:41       ` Nicolas Saenz Julienne
2018-11-06 16:06       ` Stefan Wahren
2018-11-06 16:06         ` Stefan Wahren
2018-11-06 18:28         ` Nicolas Saenz Julienne
2018-11-06 18:28           ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 10/18] staging: vchiq_core: don't add a wmb() before remote_event_signal() Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 11/18] staging: vchiq_arm: use completions instead of semaphores Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-28 21:00   ` Stefan Wahren
2018-10-28 21:00     ` Stefan Wahren
2018-10-26 13:48 ` [PATCH RFC 12/18] staging: vchiq_util: " Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 13/18] staging: vchiq_core: " Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 14/18] staging: vchiq_util: get rid of unneeded memory barriers Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` [PATCH RFC 15/18] stagning: vchiq_core: fix logic redundancy in parse_open Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-28 20:58   ` Stefan Wahren
2018-10-28 20:58     ` Stefan Wahren
2018-10-26 13:48 ` [PATCH RFC 16/18] staging: vchiq_arm: rework probe and init functions Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-28 21:02   ` Stefan Wahren
2018-10-28 21:02     ` Stefan Wahren
2018-10-26 13:48 ` [PATCH RFC 17/18] staging: vchiq_arm: fix open/release cdev functions Nicolas Saenz Julienne
2018-10-26 13:48   ` Nicolas Saenz Julienne
2018-10-26 13:48 ` Nicolas Saenz Julienne [this message]
2018-10-26 13:48   ` [PATCH RFC 18/18] staging: vchiq: add more tasks to the TODO list Nicolas Saenz Julienne
2018-10-28 21:11   ` Stefan Wahren
2018-10-28 21:11     ` Stefan Wahren

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20181026134813.7775-19-nsaenzjulienne@suse.de \
    --to=nsaenzjulienne@suse.de \
    --cc=dave.stevenson@raspberrypi.org \
    --cc=devel@driverdev.osuosl.org \
    --cc=eric@anholt.net \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rpi-kernel@lists.infradead.org \
    --cc=stefan.wahren@i2se.com \
    --subject='Re: [PATCH RFC 18/18] staging: vchiq: add more tasks to the TODO list' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.