Hi Frederic, On Thu, Oct 11, 2018 at 01:12:16AM +0200, Frederic Weisbecker wrote: > From: Frederic Weisbecker <fweis...@gmail.com> > > Make do_softirq() re-entrant and allow a vector, being either processed > or disabled, to be interrupted by another vector. This way a vector > won't be able to monopolize the CPU for a long while at the expense of > the others that may rely on some predictable latency, especially on > softirq disabled sections that used to disable all vectors. > I understand that a long running softirq can be preempted/interrupted by other softirqs which is not possible today. I have few questions on your patches.
(1) When softirq processing is pushed to ksoftirqd, then the long running softirq can still block other softirqs (not in SOFTIRQ_NOW_MASK) for a while. correct? (2) When softirqs processing happens asynchronously, a particular softirq like TASKLET can keep interrupting an already running softirq like TIMER/NET_RX, correct? In worse case scenario, a long running softirq like NET_RX interrupt a TIMER softirq. But I guess this is something expected with this. i.e each softirq is independent and whichever comes recent gets to interrupt the previously running softirqs. Thanks, Pavan -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.
