On Mon, 7 Sep 2009 15:58:50 -0700 "Luis R. Rodriguez" <mcgrof@xxxxxxxxx> wrote: > A while ago I had read about an effort to consider removing tasklets > [1] or at least trying to not use them. I'm unaware of the progress in > this respect but since reading that article have always tried to > evaluate whether or not we need tasklets on wireless drivers. I have > also wondered whether work in irq context in other parts of the kernel > can be moved to process context, a curious example being timers. I'll > personally be trying to using only process context on bottom halves on > future drivers but I figured it may be a good time to ask how serious > was avoiding tasklets or using wrappers in the future to avoid irq > context is or is it advised. Do we have a general agreement this is a > good step forward to take? Has anyone made tests or changes on a > specific driver from irq context to process context and proven there > are no significant advantages of using irq context where you would > have expected it? > > Wireless in particular should IMHO not require taskets for anything > time sensitive that I can think about except perhaps changing channels > quickly and to do that appropriately also process pending RX frames > prior to a switch. It remains to be seen experimentally whether or not > using a workqueue for RX processing would affect the time to switch > channels negatively but I doubt it would be significant. I hope to > test that with ath9k_htc. > > What about gigabit or 10 Gigabit Ethernet drivers ? Do they face any > challenges which would yet need to be proven would not face issues > when processing bottom halves in process context? > > [1] http://lwn.net/Articles/239633/ > > Luis > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html Why not use NAPI, which is soft irq? Almost all 1G and 10G drivers use NAPI. Process context is too slow. -- -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
