2009/10/3 Jean-Francois Moine <moinejf@xxxxxxx>: > On Thu, 1 Oct 2009 15:23:29 +0200 > Erik Andrén <erik.andren@xxxxxxxxx> wrote: > >> 2009/9/15 Jean-Francois Moine <moinejf@xxxxxxx>: > [snip] >> > I think you may have found a big problem, and this one should exist >> > in all drivers! >> > >> > As I understood, you say that the URB completion routine (isoc_irq) >> > may be run many times at the same time. > [snip] >> > Then, to fix this problem, I see only one solution: have a private >> > tasklet to do the video streaming, as this is done for some bulk >> > transfer... > [snip] >> Are you currently working on anything addressing this issue or do we >> need some further discussion? > > Hi Erik, > > No, I am not working on this problem: I cannot reproduce it (easy test: > have a static variable which is incremented in the irq function - > isoc_irq() in gspca.c - and warn when it is non null at entry). > > May you (or anyone) check it? > > Then, the simplest solution is not a tasklet, but to use only one URB > (change the '#define DEF_NURBS' to 1 instead of 3 in gspca.c). > But this would result in reduced performance for all gspca subdrivers, no? Best regards, Erik > Best regards. > > -- > Ken ar c'hentañ | ** Breizh ha Linux atav! ** > Jef | http://moinejf.free.fr/ > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
