Messages in this thread | | | Date | Thu, 12 Nov 2015 11:32:03 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH v3 0/2] perf/core: rcu fixes |
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On Thu, Nov 12, 2015 at 11:00:02AM +0100, Stephane Eranian wrote: > > This short patch series fixes some issues with RCU locking in the generic > perf layer. > > Patch 1 fixes cgroup switching rcu issues related to the fact that > perf_cgroup_sched_out() and perf_cgroup_sched_in() were missing some > rcu read lock to protect the reference to the cgroup. Consequently, > we moved the rcu readlock out of perf_cgroup_switch() to avoid double > calls. > > Patch 2 reinforces the testing for the rcu locking in perf cgorup code. > Either we have to hold the rcu read lock or we must have the ctx->lock > which guarantees the task cannot leave the cgroup. > > Thanks to Peter and Eric from their suggestions on how to fix this correctly. > > Stephane Eranian (2): > perf/core: fix RCU problem with cgroup context switching code > perf/core: robustify perf_cgroup_from_task rcu checks
Thanks!
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