Re: [PATCH] staging/android: use multiple futex wait queues

Hugo [0] https://lore.kernel.org/patchwork/patch/1039712/ -- Hugo Lefeuvre (hle)|www.owl.eu.com RSA4096_ 360B 03B3 BF27 4F4D 7A3F D5E8 14AA 1EB8 A247 3DFD ed25519_ 37B2 6D38 0B25 B8A2 6B9F 3A65 A36F 5357 5F2D DC4C ___ devel m

Re: [PATCH] staging/android: use multiple futex wait queues

> > + list_for_each_entry(it, >futex_wait_queue_list, list) { > > + if (wait_queue->offset == arg->offset) { > ^^ > You meant "it->offset". Right, this is not good. Fixed in v2. Thanks for the feedback!

[PATCH v2] staging/android: use multiple futex wait queues

Use multiple per-offset wait queues instead of one big wait queue per region. Signed-off-by: Hugo Lefeuvre --- Changes in v2: - dereference the it pointer instead of wait_queue (which is not set yet) in handle_vsoc_cond_wait() --- drivers/staging/android/TODO | 4 --- drivers/staging

Re: [PATCH] staging/android: use multiple futex wait queues

> > Use multiple per-offset wait queues instead of one big wait queue per > > region. > > > > Signed-off-by: Hugo Lefeuvre > > Have you tested this? > > Noticed any performance speedups or slow downs? Not yet. I have started to set up a cuttlefish test env

[PATCH] staging/android: use multiple futex wait queues

Use multiple per-offset wait queues instead of one big wait queue per region. Signed-off-by: Hugo Lefeuvre --- This patch is based on the simplify handle_vsoc_cond_wait patchset, currently under review: https://lkml.org/lkml/2019/2/7/870 --- drivers/staging/android/TODO | 4 --- drivers

Re: [PATCH 1/3] sched/wait: use freezable_schedule when possible

ael (power maintainer) on it. Thanks, I have splitted the patch set[0][1] and submitted the freezable_schedule patch separately (only cc-ing people responsible for the wait api + Rafael). regards, Hugo [0] https://lkml.org/lkml/2019/2/7/802 [1] https://lkml.org/lkml/2019/2/7/870 --

[PATCH v2 2/2] staging/android: simplify handle_vsoc_cond_wait

simplify handle_vsoc_cond_wait (drivers/staging/android/vsoc.c) using newly added wait_event_freezable_hrtimeout helper and remove duplicate include. Signed-off-by: Hugo Lefeuvre --- Changes in v2: - Fix removal of necessary linux/freezer.h include. - Make commit message more precise about

[PATCH v2 1/2] sched/wait: introduce wait_event_freezable_hrtimeout

introduce wait_event_freezable_hrtimeout, an interruptible and freezable version of wait_event_hrtimeout. This helper will allow for simplifications in staging/android/vsoc.c, among others. Signed-off-by: Hugo Lefeuvre --- Changes in v2: - No change. include/linux/wait.h | 25

[PATCH v2 0/2] sched/wait, staging/android: simplification of freeze related code

: use freezable_schedule when possible", it was submitted separately. - Patch 3/3 (now 2/2): Fix removal of a necessary linux/freezer.h include and improve commit message. [1] v1: https://lkml.org/lkml/2019/2/1/19 Hugo Lefeuvre (2): sched/wait: introduce wait_event_freezable_hrtimeout

Re: [PATCH 1/3] sched/wait: use freezable_schedule when possible

lines in kern.log. Results: Without my patch: 448 calls freeze_task, 12 skipped. With my patch: 448 calls, 32 skipped. 2.6x more tasks skipped. Not sure this is the best way to test this patch, though. Any advice? regards, Hugo -- Hugo Lefeuvre (hle)|www.owl.eu.c

Re: [PATCH 1/3] sched/wait: use freezable_schedule when possible

emoves a necessary #include . I will submit an updated version tomorrow. Thanks for the review! regards, Hugo -- Hugo Lefeuvre (hle)|www.owl.eu.com RSA4096_ 360B 03B3 BF27 4F4D 7A3F D5E8 14AA 1EB8 A247 3DFD ed25519_ 37B2 6D38 0B25 B8A2 6B9F 3A65 A36F 5357 5F2

Re: [PATCH] sched/wait: introduce wait_event_freezable_hrtimeout

egards, Hugo -- Hugo Lefeuvre (hle)|www.owl.eu.com RSA4096_ 360B 03B3 BF27 4F4D 7A3F D5E8 14AA 1EB8 A247 3DFD ed25519_ 37B2 6D38 0B25 B8A2 6B9F 3A65 A36F 5357 5F2D DC4C signature.asc Description: PGP signature ___ devel mailing l

[PATCH 3/3] staging/android: simplify handle_vsoc_cond_wait

simplify handle_vsoc_cond_wait (drivers/staging/android/vsoc.c) using newly added wait_event_freezable_hrtimeout helper and remove useless includes. Signed-off-by: Hugo Lefeuvre --- drivers/staging/android/vsoc.c | 69 +- 1 file changed, 10 insertions(+), 59

[PATCH 1/3] sched/wait: use freezable_schedule when possible

try_to_freeze() when they wake up if the freeze is still underway. It is not a problem since sleeping tasks can't do anything which isn't allowed for a frozen task while sleeping. The result is a potential performance gain during freeze, since less tasks have to be awaken. Signed-off-by: Hugo

[PATCH 2/3] sched/wait: introduce wait_event_freezable_hrtimeout

introduce wait_event_freezable_hrtimeout, an interruptible and freezable version of wait_event_hrtimeout. Among others this helper will allow for simplifications in staging/android/vsoc.c. Signed-off-by: Hugo Lefeuvre --- include/linux/wait.h | 25 + 1 file changed, 21

[PATCH 0/3] sched/wait, staging/android: simplification and optimization of freeze related code

[0] https://lkml.org/lkml/2019/1/17/877 [1] https://lkml.org/lkml/2019/1/19/58 Hugo Lefeuvre (3): sched/wait: use freezable_schedule when possible sched/wait: introduce wait_event_freezable_hrtimeout staging/android: simplify handle_vsoc_cond_wait drivers/staging/android/v

Re: [PATCH] sched/wait: introduce wait_event_freezable_hrtimeout

regards, Hugo [0] https://elixir.bootlin.com/linux/latest/source/include/linux/freezer.h#L103 [1] https://elixir.bootlin.com/linux/latest/source/Documentation/power/freezing-of-tasks.txt#L90 [2] https://elixir.bootlin.com/linux/latest/source/kernel/kthread.c#L569 -- Hugo Lefeuvr

Re: [PATCH] sched/wait: introduce wait_event_freezable_hrtimeout

during the schedule() call, but in the end try_to_freeze() is still called so the result is the same, right? I wonder why wait_event_freezable is not calling freezable_schedule(). That being said, I am not sure that the try_to_freeze() call does anything in the vsoc case because there is no

Re: [PATCH] sched/wait: introduce wait_event_freezable_hrtimeout

Hi Greg, > > introduce wait_event_freezable_hrtimeout, an interruptible and freezable > > version of wait_event_hrtimeout. > > > > simplify handle_vsoc_cond_wait (drivers/staging/android/vsoc.c) using this > > newly added helper and remove useless includes. > &g

[PATCH] sched/wait: introduce wait_event_freezable_hrtimeout

introduce wait_event_freezable_hrtimeout, an interruptible and freezable version of wait_event_hrtimeout. simplify handle_vsoc_cond_wait (drivers/staging/android/vsoc.c) using this newly added helper and remove useless includes. Signed-off-by: Hugo Lefeuvre --- drivers/staging/android/vsoc.c

Re: staging/android: questions regarding TODO entries

> It should probably say "address." Thanks. I'm working on a few patches for staging/android, this issue will be addressed as well. regards, Hugo -- Hugo Lefeuvre (hle)|www.owl.eu.com RSA4096_ 360B 03B3 BF27 4F4D 7A3F D5E8 14AA 1EB8 A247 3DFD ed25519_ 3

staging/android: questions regarding TODO entries

. So, once VSOC_SELF_INTERRUPT has been executed once, VSOC_WAIT_FOR_INCOMING_INTERRUPT doesn't work anymore ? Thanks for your work ! cheers, Hugo PS: cc-ing the result of get_maintainer.pl + contacts from todo. Please tell me if this is not the right way to go. -- Hugo Lef

pi433: initialization of tx config in pi433_open()

fault values of the rf69 datasheet[0] ? Also, is there a specific reason why you chose 4711 as a default value for the bit rate ? I couldn't find it anywhere in the datasheet nor on the internet. Thanks ! Regards, Hugo [0] http://www.hoperf.com/upload/rf/RFM69CW-V1.1.pdf -- Hugo L

Re: rf69_set_deviation in rf69.c (pi433 driver)

nted to have your opinion > > on this. > > Agree. I'll prepare a patch addressing both issues. However I don't own test devices so it would be really great if you could test it ! I'm currently thinking of adapting this driver for other HopeRf modules like RFM69HCW or RFM12 so I will pro

Re: [PATCH v2] staging: pi433: fix race condition in pi433_open

On Wed, Jun 20, 2018 at 11:34:39AM +0300, Dan Carpenter wrote: > On Tue, Jun 19, 2018 at 10:33:26PM -0400, Hugo Lefeuvre wrote: > > @@ -1178,6 +1152,11 @@ static int pi433_probe(struct spi_device *spi) > > device->tx_active = false; > > device->i

[PATCH v3] staging: pi433: fix race condition in pi433_open

counter and move rx buffer {de,}allocation to probe() and remove(). Remove associated dead code from open() and release(). Remove related TODO entry from ioctl(). Signed-off-by: Hugo Lefeuvre --- Changes in v3: - add missing free call in probe() (in case of failure during memory allocation

[PATCH v2] staging: pi433: fix race condition in pi433_open

counter and move rx buffer {de,}allocation to probe() and remove(). Remove associated dead code from open() and release(). Remove related TODO entry from ioctl(). Signed-off-by: Hugo Lefeuvre --- Changes in v2: - Remove useless users counter. - Remove unneeded TODO entry in ioctl

Re: [PATCH] staging: pi433: fix race condition in pi433_open

/* make sure ops on existing fds can abort cleanly */ > > 1297 device->spi = NULL; > > That's when we're unloading the module so there aren't any users left. I'll submit an updated version of my patch getting rid of the counter and addressing the remaining race conditions. Thanks

Re: [PATCH] staging: pi433: fix race condition in pi433_open

ces: 1296 /* make sure ops on existing fds can abort cleanly */ 1297 device->spi = NULL; Thanks for your time ! Regards, Hugo -- Hugo Lefeuvre (hle)|www.owl.eu.com 4096/ 9C4F C8BF A4B0 8FC5 48EB 56B8 1962 765B B9A8 BACA ___

[PATCH] staging: pi433: fix race condition in pi433_open

f minor_lock in pi433_open(). Signed-off-by: Hugo Lefeuvre --- drivers/staging/pi433/pi433_if.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/staging/pi433/pi433_if.c b/drivers/staging/pi433/pi433_if.c index 94e0bfcec991..73c511249f7f 100644 --- a/drivers/staging/pi43

Re: [PATCH v3] staging: pi433: fix race condition in pi433_ioctl

fixed in v4. Sorry for the noise. -- Hugo Lefeuvre (hle)|www.owl.eu.com 4096/ 9C4F C8BF A4B0 8FC5 48EB 56B8 1962 765B B9A8 BACA signature.asc Description: PGP signature ___ devel mailing list de...@linuxdriv

Re: [PATCH v2] staging: pi433: fix race condition in pi433_ioctl

if (copy_from_user(_cfg_buffer, argp, > > + sizeof(struct pi433_tx_cfg))) { > > Sorry for the duplicate review, but it got sent to both my inboxes... :P Thanks for your review ! Patch updated. Please tell me if you don't to be CC-ed anymore. :) regard

[PATCH v4] staging: pi433: fix race condition in pi433_ioctl

_CFG case in pi433_ioctl. Also, do not copy data directly from user space to instance->tx_cfg. Instead use a temporary buffer allowing future checks for correctness of copied data and simpler code. Signed-off-by: Hugo Lefeuvre --- Changes in v4: - Fix incorrect buffer name in memcpy. --- drivers/s

[PATCH v3] staging: pi433: fix race condition in pi433_ioctl

_CFG case in pi433_ioctl. Also, do not copy data directly from user space to instance->tx_cfg. Instead use a temporary buffer allowing future checks for correctness of copied data and simpler code. Signed-off-by: Hugo Lefeuvre --- Changes in v3: - Use tx_cfg for the name of temporary buffer (sho

[PATCH v2] staging: pi433: fix race condition in pi433_ioctl

_CFG case in pi433_ioctl. Also, do not copy data directly from user space to instance->tx_cfg. Instead use a temporary buffer allowing future checks for correctness of copied data. Signed-off-by: Hugo Lefeuvre --- Changes in v2: - Use device->tx_fifo_lock instead of introducing a new lock in

Re: [PATCH v2] staging: pi433: add mutex fixing concurrency issues.

en to the fifo by pi433_write. What kind of checks do you want to perform exactly ? But, right, I prefer the idea of the temporary buffer too, and seeing the rest of kernel code it seems to be the usual way to go. Regards, Hugo -- Hugo Lefeuvre (hle)|www.owl.eu.com 4096

Re: [PATCH] staging: pi433: add mutex fixing race condition when accessing tx_cfg

don't even need to introduce a new lock, using device->tx_fifo_lock should be fine. I'll update the patch. -- Hugo Lefeuvre (hle)|www.owl.eu.com 4096/ 9C4F C8BF A4B0 8FC5 48EB 56B8 1962 765B B9A8 BACA signature.asc Descript

[PATCH] staging: pi433: add mutex fixing race condition when accessing tx_cfg

enter in an inconsistent state. Add a mutex making sure that the PI433_IOC_WR_TX_CFG case will never be run by several threads concurrently. Signed-off-by: Hugo Lefeuvre --- drivers/staging/pi433/pi433_if.c | 9 - 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/staging

Re: [PATCH v2] staging: pi433: add mutex fixing concurrency issues.

test it because I don't have test devices. -- Hugo Lefeuvre (hle)|www.owl.eu.com 4096/ 9C4F C8BF A4B0 8FC5 48EB 56B8 1962 765B B9A8 BACA ___ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Re: [PATCH v2] staging: pi433: add mutex fixing concurrency issues.

_data, which > wraps struct pi433_instance and its mutex. > > Make filp->private_data point to a struct pi433_data, allowing to > acquire the lock before accessing the struct pi433_instance. > > Signed-off-by: Hugo Lefeuvre > --- > Changes in v2: > - Use mutex

rf69_set_deviation in rf69.c (pi433 driver)

nything, simply expose API) I'd really prefer going for the first one, but I wanted to have your opinion on this. Thanks for your work ! Best regards, Hugo [0] http://www.hoperf.com/upload/rf/RFM69CW-V1.1.pdf [CC-ing Valentin Vidic, he was quite active on the pi433 driver these last months]

Re: [PATCH] staging: pi433: add rw semaphore fixing concurrency issues

wrapper struct pi433_data which would contain pointers to the pi433_instance and its mutex. I couldn't find any similar situation in the kernel, so I'm not sure it's the right way to go though. Thanks ! Regards, Hugo -- Hugo Lefeuvre (hle)|www.owl.eu.com 4096/ 9C4F C8BF A4B0

[PATCH v2] staging: pi433: add mutex fixing concurrency issues.

ilp->private_data point to a struct pi433_data, allowing to acquire the lock before accessing the struct pi433_instance. Signed-off-by: Hugo Lefeuvre --- Changes in v2: - Use mutex instead of rw semaphore. - Introduce struct pi433_data in order to allow functions t

Re: [PATCH] staging: pi433: add rw semaphore fixing concurrency issues

dn't notice it. Thanks ! Otherwise, do you think the usage of rw semaphore is appropriate in this case ? Regards, Hugo -- Hugo Lefeuvre (hle)|www.owl.eu.com 4096/ 9C4F C8BF A4B0 8FC5 48EB 56B8 1962 765B B9A8 BACA ___ devel mailing

[PATCH] staging: pi433: add rw semaphore fixing concurrency issues

lso affect pi433_write and pi433_read. The newly introduced semaphore makes sure that filp->private_data will not be freed by pi433_release (writer) as long as pi433_write, pi433_read or pi433_ioctl (readers) are still executing. Signed-off-by: Hugo Lefeuvre --- drivers/staging/pi433/pi433_if.