| Message ID | B256D81BAE5131468A838E5D7A24364172FF9685@penmbx01 |
|---|---|
| State | New |
| Headers | show |
Hi, patch applied, it helps. Is this final solution? Thanks Dne 10.3.2014 10:08, Yang, Wenyou napsal(a): > > >> -----Original Message----- >> From: Jiří Prchal [mailto:jiri.prchal@aksignal.cz] >> Sent: Monday, March 10, 2014 4:12 PM >> To: Rabin Vincent; Alexandre Belloni; Yang, Wenyou >> Cc: Ferre, Nicolas; linux-arm-kernel@lists.infradead.org; >> sboyd@codeaurora.org >> Subject: Re: [BUG] atmel: spi: scheduling while atomic >> >> Hi all, >> at first: warning is on all spi devices. >> at second: its with CONFIG_PREEMPT=y, without (# CONFIG_PREEMPT_RCU is >> not set) is OK, but I wonder if this config will be fast enough for our >> usage (nearly RT)? >> >> >> Dne 8.3.2014 01:41, Rabin Vincent napsal(a): >>> 2014-03-07 23:58 GMT+01:00 Alexandre Belloni >>> <alexandre.belloni@free-electrons.com>: >>>> On 05/03/2014 at 07:56:04 +0100, Jiří Prchal wrote : >>>>> [ 0.902343] BUG: scheduling while atomic: spi0/383/0x00000002 >>>>> [ 0.906250] Modules linked in: >>>>> [ 0.906250] CPU: 0 PID: 383 Comm: spi0 Not tainted 3.14.0- >> rc4_cpm9g25+ #1 >>>>> [ 0.906250] [<c000d9f4>] (unwind_backtrace) from [<c000bdc0>] >> (show_stack+0x10/0x14) >>>>> [ 0.906250] [<c000bdc0>] (show_stack) from [<c003a224>] >> (__schedule_bug+0x48/0x60) >>>>> [ 0.906250] [<c003a224>] (__schedule_bug) from [<c0390294>] >> (__schedule+0x60/0x484) >>>>> [ 0.906250] [<c0390294>] (__schedule) from [<c038feac>] >> (schedule_timeout+0x17c/0x1ac) >>>>> [ 0.906250] [<c038feac>] (schedule_timeout) from [<c039111c>] >> (wait_for_common+0x10c/0x1f0) >>>>> [ 0.906250] [<c039111c>] (wait_for_common) from [<c0249228>] >> (atmel_spi_transfer_one_message+0x71c/0xa48) >>>>> [ 0.906250] [<c0249228>] (atmel_spi_transfer_one_message) from >> [<c0246624>] (spi_pump_messages+0x210/0x238) >>>>> [ 0.906250] [<c0246624>] (spi_pump_messages) from [<c00343d0>] >> (kthread_worker_fn+0x15c/0x1b4) >>>>> [ 0.906250] [<c00343d0>] (kthread_worker_fn) from [<c0034534>] >> (kthread+0xb8/0xcc) >>>>> [ 0.906250] [<c0034534>] (kthread) from [<c0009510>] >> (ret_from_fork+0x14/0x24) >>>>> [ 0.906250] at25 spi0.0: 128 KByte at25 eeprom, pagesize 512 >>>> >>>> Actually, I'm not quite sure how spi_pump_messages can be called from >> an >>>> atomic context. >>> >>> spi_pump_messages() is not called from atomic context. Rather, >>> atmel_spi_transfer_one_message() does a spin_lock_irqsave() (via >>> atmel_spi_lock()) and then calls atmel_spi_one_transfer(), which calls >>> wait_for_completion_timeout(). That's why schedule is being called >>> from atomic context. This was introduced by 8090d6d1a4 ("spi: atmel: >>> Refactor spi-atmel to use SPI framework queue"). I think you should >>> see the warning with CONFIG_PREEMPT=y. >>> > > Thanks a lot for the report and analysis. > > --->8-------- > From ba2dd7aee12cb09b9ef159251859443e1b055669 Mon Sep 17 00:00:00 2001 > From: Wenyou Yang <wenyou.yang@atmel.com> > Date: Mon, 10 Mar 2014 16:44:33 +0800 > Subject: [PATCH] spi: atmel: fix BUG: scheduling while atomic with > CONFIG_PREEMPT=y > > introduced by 8090d6d1a415d3ae1a7208995decfab8f60f4f36 > ("spi: atmel: Refactor spi-atmel to use SPI framework queue") > > Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com> > --- > drivers/spi/spi-atmel.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c > index b0842f7..e05c3f2 100644 > --- a/drivers/spi/spi-atmel.c > +++ b/drivers/spi/spi-atmel.c > @@ -1130,8 +1130,12 @@ static int atmel_spi_one_transfer(struct spi_master *master, > atmel_spi_next_xfer_pio(master, xfer); > } > > + atmel_spi_unlock(as); > + > ret = wait_for_completion_timeout(&as->xfer_completion, > SPI_DMA_TIMEOUT); > + atmel_spi_lock(as); > + > if (WARN_ON(ret == 0)) { > dev_err(&spi->dev, > "spi trasfer timeout, err %d\n", ret); >
> -----Original Message----- > From: Jiří Prchal [mailto:jiri.prchal@aksignal.cz] > Sent: Tuesday, March 11, 2014 5:46 PM > To: Yang, Wenyou; Rabin Vincent; Alexandre Belloni > Cc: Ferre, Nicolas; linux-arm-kernel@lists.infradead.org; > sboyd@codeaurora.org > Subject: Re: [BUG] atmel: spi: scheduling while atomic > > Hi, > patch applied, it helps. > Is this final solution? > Thanks Thank for your feedback. There isn't a better solution so far. Best Regards, Wenyou Yang > > Dne 10.3.2014 10:08, Yang, Wenyou napsal(a): > > > > > >> -----Original Message----- > >> From: Jiří Prchal [mailto:jiri.prchal@aksignal.cz] > >> Sent: Monday, March 10, 2014 4:12 PM > >> To: Rabin Vincent; Alexandre Belloni; Yang, Wenyou > >> Cc: Ferre, Nicolas; linux-arm-kernel@lists.infradead.org; > >> sboyd@codeaurora.org > >> Subject: Re: [BUG] atmel: spi: scheduling while atomic > >> > >> Hi all, > >> at first: warning is on all spi devices. > >> at second: its with CONFIG_PREEMPT=y, without (# CONFIG_PREEMPT_RCU > >> is not set) is OK, but I wonder if this config will be fast enough > >> for our usage (nearly RT)? > >> > >> > >> Dne 8.3.2014 01:41, Rabin Vincent napsal(a): > >>> 2014-03-07 23:58 GMT+01:00 Alexandre Belloni > >>> <alexandre.belloni@free-electrons.com>: > >>>> On 05/03/2014 at 07:56:04 +0100, Jiří Prchal wrote : > >>>>> [ 0.902343] BUG: scheduling while atomic: spi0/383/0x00000002 > >>>>> [ 0.906250] Modules linked in: > >>>>> [ 0.906250] CPU: 0 PID: 383 Comm: spi0 Not tainted 3.14.0- > >> rc4_cpm9g25+ #1 > >>>>> [ 0.906250] [<c000d9f4>] (unwind_backtrace) from [<c000bdc0>] > >> (show_stack+0x10/0x14) > >>>>> [ 0.906250] [<c000bdc0>] (show_stack) from [<c003a224>] > >> (__schedule_bug+0x48/0x60) > >>>>> [ 0.906250] [<c003a224>] (__schedule_bug) from [<c0390294>] > >> (__schedule+0x60/0x484) > >>>>> [ 0.906250] [<c0390294>] (__schedule) from [<c038feac>] > >> (schedule_timeout+0x17c/0x1ac) > >>>>> [ 0.906250] [<c038feac>] (schedule_timeout) from [<c039111c>] > >> (wait_for_common+0x10c/0x1f0) > >>>>> [ 0.906250] [<c039111c>] (wait_for_common) from [<c0249228>] > >> (atmel_spi_transfer_one_message+0x71c/0xa48) > >>>>> [ 0.906250] [<c0249228>] (atmel_spi_transfer_one_message) from > >> [<c0246624>] (spi_pump_messages+0x210/0x238) > >>>>> [ 0.906250] [<c0246624>] (spi_pump_messages) from [<c00343d0>] > >> (kthread_worker_fn+0x15c/0x1b4) > >>>>> [ 0.906250] [<c00343d0>] (kthread_worker_fn) from [<c0034534>] > >> (kthread+0xb8/0xcc) > >>>>> [ 0.906250] [<c0034534>] (kthread) from [<c0009510>] > >> (ret_from_fork+0x14/0x24) > >>>>> [ 0.906250] at25 spi0.0: 128 KByte at25 eeprom, pagesize 512 > >>>> > >>>> Actually, I'm not quite sure how spi_pump_messages can be called > >>>> from > >> an > >>>> atomic context. > >>> > >>> spi_pump_messages() is not called from atomic context. Rather, > >>> atmel_spi_transfer_one_message() does a spin_lock_irqsave() (via > >>> atmel_spi_lock()) and then calls atmel_spi_one_transfer(), which > >>> calls wait_for_completion_timeout(). That's why schedule is being > >>> called from atomic context. This was introduced by 8090d6d1a4 ("spi: > atmel: > >>> Refactor spi-atmel to use SPI framework queue"). I think you should > >>> see the warning with CONFIG_PREEMPT=y. > >>> > > > > Thanks a lot for the report and analysis. > > > > --->8-------- > > From ba2dd7aee12cb09b9ef159251859443e1b055669 Mon Sep 17 00:00:00 > > 2001 > > From: Wenyou Yang <wenyou.yang@atmel.com> > > Date: Mon, 10 Mar 2014 16:44:33 +0800 > > Subject: [PATCH] spi: atmel: fix BUG: scheduling while atomic with > > CONFIG_PREEMPT=y > > > > introduced by 8090d6d1a415d3ae1a7208995decfab8f60f4f36 > > ("spi: atmel: Refactor spi-atmel to use SPI framework queue") > > > > Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com> > > --- > > drivers/spi/spi-atmel.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index > > b0842f7..e05c3f2 100644 > > --- a/drivers/spi/spi-atmel.c > > +++ b/drivers/spi/spi-atmel.c > > @@ -1130,8 +1130,12 @@ static int atmel_spi_one_transfer(struct > spi_master *master, > > atmel_spi_next_xfer_pio(master, xfer); > > } > > > > + atmel_spi_unlock(as); > > + > > ret = wait_for_completion_timeout(&as->xfer_completion, > > SPI_DMA_TIMEOUT); > > + atmel_spi_lock(as); > > + > > if (WARN_ON(ret == 0)) { > > dev_err(&spi->dev, > > "spi trasfer timeout, err %d\n", ret); > >
So shouldn't we (you) apply it to mainstream? Dne 11.3.2014 10:54, Yang, Wenyou napsal(a): > >> -----Original Message----- >> From: Jiří Prchal [mailto:jiri.prchal@aksignal.cz] >> Sent: Tuesday, March 11, 2014 5:46 PM >> To: Yang, Wenyou; Rabin Vincent; Alexandre Belloni >> Cc: Ferre, Nicolas; linux-arm-kernel@lists.infradead.org; >> sboyd@codeaurora.org >> Subject: Re: [BUG] atmel: spi: scheduling while atomic >> >> Hi, >> patch applied, it helps. >> Is this final solution? >> Thanks > > Thank for your feedback. > There isn't a better solution so far. > > Best Regards, > Wenyou Yang > >> >> Dne 10.3.2014 10:08, Yang, Wenyou napsal(a): >>> >>> >>>> -----Original Message----- >>>> From: Jiří Prchal [mailto:jiri.prchal@aksignal.cz] >>>> Sent: Monday, March 10, 2014 4:12 PM >>>> To: Rabin Vincent; Alexandre Belloni; Yang, Wenyou >>>> Cc: Ferre, Nicolas; linux-arm-kernel@lists.infradead.org; >>>> sboyd@codeaurora.org >>>> Subject: Re: [BUG] atmel: spi: scheduling while atomic >>>> >>>> Hi all, >>>> at first: warning is on all spi devices. >>>> at second: its with CONFIG_PREEMPT=y, without (# CONFIG_PREEMPT_RCU >>>> is not set) is OK, but I wonder if this config will be fast enough >>>> for our usage (nearly RT)? >>>> >>>> >>>> Dne 8.3.2014 01:41, Rabin Vincent napsal(a): >>>>> 2014-03-07 23:58 GMT+01:00 Alexandre Belloni >>>>> <alexandre.belloni@free-electrons.com>: >>>>>> On 05/03/2014 at 07:56:04 +0100, Jiří Prchal wrote : >>>>>>> [ 0.902343] BUG: scheduling while atomic: spi0/383/0x00000002 >>>>>>> [ 0.906250] Modules linked in: >>>>>>> [ 0.906250] CPU: 0 PID: 383 Comm: spi0 Not tainted 3.14.0- >>>> rc4_cpm9g25+ #1 >>>>>>> [ 0.906250] [<c000d9f4>] (unwind_backtrace) from [<c000bdc0>] >>>> (show_stack+0x10/0x14) >>>>>>> [ 0.906250] [<c000bdc0>] (show_stack) from [<c003a224>] >>>> (__schedule_bug+0x48/0x60) >>>>>>> [ 0.906250] [<c003a224>] (__schedule_bug) from [<c0390294>] >>>> (__schedule+0x60/0x484) >>>>>>> [ 0.906250] [<c0390294>] (__schedule) from [<c038feac>] >>>> (schedule_timeout+0x17c/0x1ac) >>>>>>> [ 0.906250] [<c038feac>] (schedule_timeout) from [<c039111c>] >>>> (wait_for_common+0x10c/0x1f0) >>>>>>> [ 0.906250] [<c039111c>] (wait_for_common) from [<c0249228>] >>>> (atmel_spi_transfer_one_message+0x71c/0xa48) >>>>>>> [ 0.906250] [<c0249228>] (atmel_spi_transfer_one_message) from >>>> [<c0246624>] (spi_pump_messages+0x210/0x238) >>>>>>> [ 0.906250] [<c0246624>] (spi_pump_messages) from [<c00343d0>] >>>> (kthread_worker_fn+0x15c/0x1b4) >>>>>>> [ 0.906250] [<c00343d0>] (kthread_worker_fn) from [<c0034534>] >>>> (kthread+0xb8/0xcc) >>>>>>> [ 0.906250] [<c0034534>] (kthread) from [<c0009510>] >>>> (ret_from_fork+0x14/0x24) >>>>>>> [ 0.906250] at25 spi0.0: 128 KByte at25 eeprom, pagesize 512 >>>>>> >>>>>> Actually, I'm not quite sure how spi_pump_messages can be called >>>>>> from >>>> an >>>>>> atomic context. >>>>> >>>>> spi_pump_messages() is not called from atomic context. Rather, >>>>> atmel_spi_transfer_one_message() does a spin_lock_irqsave() (via >>>>> atmel_spi_lock()) and then calls atmel_spi_one_transfer(), which >>>>> calls wait_for_completion_timeout(). That's why schedule is being >>>>> called from atomic context. This was introduced by 8090d6d1a4 ("spi: >> atmel: >>>>> Refactor spi-atmel to use SPI framework queue"). I think you should >>>>> see the warning with CONFIG_PREEMPT=y. >>>>> >>> >>> Thanks a lot for the report and analysis. >>> >>> --->8-------- >>> From ba2dd7aee12cb09b9ef159251859443e1b055669 Mon Sep 17 00:00:00 >>> 2001 >>> From: Wenyou Yang <wenyou.yang@atmel.com> >>> Date: Mon, 10 Mar 2014 16:44:33 +0800 >>> Subject: [PATCH] spi: atmel: fix BUG: scheduling while atomic with >>> CONFIG_PREEMPT=y >>> >>> introduced by 8090d6d1a415d3ae1a7208995decfab8f60f4f36 >>> ("spi: atmel: Refactor spi-atmel to use SPI framework queue") >>> >>> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com> >>> --- >>> drivers/spi/spi-atmel.c | 4 ++++ >>> 1 file changed, 4 insertions(+) >>> >>> diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index >>> b0842f7..e05c3f2 100644 >>> --- a/drivers/spi/spi-atmel.c >>> +++ b/drivers/spi/spi-atmel.c >>> @@ -1130,8 +1130,12 @@ static int atmel_spi_one_transfer(struct >> spi_master *master, >>> atmel_spi_next_xfer_pio(master, xfer); >>> } >>> >>> + atmel_spi_unlock(as); >>> + >>> ret = wait_for_completion_timeout(&as->xfer_completion, >>> SPI_DMA_TIMEOUT); >>> + atmel_spi_lock(as); >>> + >>> if (WARN_ON(ret == 0)) { >>> dev_err(&spi->dev, >>> "spi trasfer timeout, err %d\n", ret); >>>
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index b0842f7..e05c3f2 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -1130,8 +1130,12 @@ static int atmel_spi_one_transfer(struct spi_master *master, atmel_spi_next_xfer_pio(master, xfer); } + atmel_spi_unlock(as); + ret = wait_for_completion_timeout(&as->xfer_completion, SPI_DMA_TIMEOUT); + atmel_spi_lock(as); + if (WARN_ON(ret == 0)) { dev_err(&spi->dev, "spi trasfer timeout, err %d\n", ret);