| Message ID | ur61ukc3x.wl%morimoto.kuninori@renesas.com (mailing list archive) |
|---|---|
| State | RFC |
| Headers | show |
On Thu, 19 Feb 2009, morimoto.kuninori@renesas.com wrote: > > Dear Guennadi > > > Hm, ok, maybe I can ask you about one more test, if you don't mind. The > > thing is, you only see the problem, if after the ->active buffer has been > > freed in free_buffer(), your DMA engine continues writing to the freed > > memory, but you only notice this, if some other driver manages to grab and > > use it in this time, then its data is going to be overwritten. > (snip) > > Best would be to first try all three loops without the patch from Magnus > > and see if any of them triggers. And use a larger frame (maximum that your > > sensor can deliver) to give the DMA engine more time per frame. > > Hmm. maybe I could understand... > > OK. > I tested with MigoR + ov772x + following way. > > 1) apply patch to kernel > > > diff -u a/drivers/media/video/sh_mobile_ceu_camera.c b/drivers/media/video/sh_mobile_ceu_camera.c > > --- a/drivers/media/video/sh_mobile_ceu_camera.c > > +++ b/drivers/media/video/sh_mobile_ceu_camera.c > > @@ -326,6 +326,7 @@ > > spin_lock_irqsave(&pcdev->lock, flags); > > > > vb = pcdev->active; > > + WARN_ON(vb->state == VIDEOBUF_NEEDS_INIT); > > list_del_init(&vb->queue); > > > > if (!list_empty(&pcdev->capture)) > > 2) apply patch to capture-example > > I think your wanting to say is this... > > diff -u capture_example.c capture_example.c.test > --- capture_example.c 2009-01-24 09:35:12.000000000 +0900 > +++ capture_example.c.test 2009-02-19 18:09:32.000000000 +0900 > @@ -590,6 +590,8 @@ > > int main(int argc, char **argv) > { > + int i; > + > dev_name = "/dev/video0"; > > for (;;) { > @@ -648,11 +650,14 @@ > } > > open_device(); > - init_device(); > - start_capturing(); > - mainloop(); > - stop_capturing(); > - uninit_device(); > + for (i=0 ; i<100 ; i++) { > + printf("%d ", i); > + init_device(); > + start_capturing(); > + mainloop(); > + stop_capturing(); > + uninit_device(); > + } > close_device(); > fprintf(stderr, "\n"); > return 0; > > 3) test this capture_example. > > Then, It say > > ====================================================================== > camera 0-0: SuperH Mobile CEU driver attached to camera 0 > camera_host0: Format 0 not found > .0 ... camera_host0: Format 0 not found > ------------[ cut here ]------------ > Badness at 8c141b9e [verbose debug info unavailable] > > Pid : 869, Comm: c2 > CPU : 0 Not tainted (2.6.29-rc4-00197-g41480ae-dirty #801) > > PC is at sh_mobile_ceu_irq+0x2a/0xc8 > PR is at handle_IRQ_event+0x2e/0x68 > PC : 8c141b9e SP : 8fe15e40 SR : 400001f1 TEA : 2961ba40 > R0 : 8ff05afc R1 : 00000000 R2 : 8fe14000 R3 : 00000000 > R4 : 8ff05a00 R5 : 8ff05a00 R6 : 00000010 R7 : 00000000 > R8 : 8ff416e0 R9 : 000000f0 R10 : 00000000 R11 : 00000034 > R12 : 8ff414d0 R13 : 8ff3a1e0 R14 : 8ff89e74 > MACH: 00000000 MACL: 00000c30 GBR : 29686450 PR : 8c030e0a > > Call trace: > [<8c030e0a>] handle_IRQ_event+0x2e/0x68 > [<8c0326a8>] handle_level_irq+0x6c/0x100 > [<8c00356c>] do_IRQ+0x34/0x5c > [<8c007118>] ret_from_irq+0x0/0x10 > [<8c003538>] do_IRQ+0x0/0x5c > [<8c0f2c44>] memset+0x30/0x4c > [<8c00b25a>] dma_alloc_coherent+0x5e/0x148 > [<8c141742>] __videobuf_mmap_mapper+0xbe/0x1a4 > [<8c13fb88>] videobuf_mmap_mapper+0x3c/0x70 > [<8c050ad8>] mmap_region+0x184/0x34c > [<8c005234>] old_mmap+0x60/0xa8 > [<8c007266>] syscall_call+0xc/0x10 > [<8c0051d4>] old_mmap+0x0/0xa8 Yesss! There you go - this is the race we are hunting. > camera 0-0: SuperH Mobile CEU driver detached from camera 0 > Trace/breakpoint trap > ====================================================================== > > 4) apply Magnus patch > 5) and test it again > > then It say... > > ======================================================== > -bash-3.00# ./c2 -d /dev/video0 -f -c 4 > camera 0-0: SuperH Mobile CEU driver attached to camera 0 > camera_host0: Format 0 not found > .0 ... camera_host0: Format 0 not found > .1 ... camera_host0: Format 0 not found > .2 ... camera_host0: Format 0 not found > .3 ... camera_host0: Format 0 not found > (snip) > .96 ... camera_host0: Format 0 not found > .97 ... camera_host0: Format 0 not found > .98 ... camera_host0: Format 0 not found > .99 ...camera 0-0: SuperH Mobile CEU driver detached from camera 0 > ======================================================== Nice and clean. Good, now I just need a formal patch submission with a "Tested-by" string, please. Thanks Guennadi --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Dear Guennadi > > ------------[ cut here ]------------ > > Badness at 8c141b9e [verbose debug info unavailable] > > > > Pid : 869, Comm: c2 > > CPU : 0 Not tainted (2.6.29-rc4-00197-g41480ae-dirty #801) (snip) > Yesss! There you go - this is the race we are hunting. (snip) > Nice and clean. Good, now I just need a formal patch submission with a > "Tested-by" string, please. Fuuu. good !! Thank you. Tested-by: Kuninori Morimoto <morimoto.kuninori@renesas.com> Best regards -- Kuninori Morimoto -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff -u capture_example.c capture_example.c.test --- capture_example.c 2009-01-24 09:35:12.000000000 +0900 +++ capture_example.c.test 2009-02-19 18:09:32.000000000 +0900 @@ -590,6 +590,8 @@ int main(int argc, char **argv) { + int i; + dev_name = "/dev/video0"; for (;;) { @@ -648,11 +650,14 @@ } open_device(); - init_device(); - start_capturing(); - mainloop(); - stop_capturing(); - uninit_device(); + for (i=0 ; i<100 ; i++) { + printf("%d ", i); + init_device(); + start_capturing(); + mainloop(); + stop_capturing(); + uninit_device(); + } close_device(); fprintf(stderr, "\n"); return 0;