On Wednesday, October 08, 2014 10:54:41 PM Peter Zijlstra wrote: > On Thu, Sep 25, 2014 at 04:32:02PM +0800, Lan Tianyu wrote: > > This patchset is to parallel enabling nonboot cpus with resuming devices > > during system resume in order to accelerate S2RAM. From test result on > > a 8 logical core Haswell machine, system resume time reduces from 347ms > > to 217ms with this patchset. > > > > In the current world, all nonboot cpus are enabled serially during system > > resume. System resume sequence is that boot cpu enables nonboot cpu one by > > one and then resume devices. Before resuming devices, there are few tasks > > assigned to nonboot cpus after they are brought up. This wastes cpu usage. > > > > This patchset is to allow boot cpu to go forward to resume devices after > > bringing up one nonboot cpu and starting a thread. The thread will be in > > charge of bringing up other frozen cpus. The thread will be scheduled to > > the first online cpu to run . This makes enabling cpu2~x parallel with > > resuming devices. > > So I feel we should really clean up hotplug before doing anything like > this. Its a trainwreck and just piling more and more hacks ontop isn't > going to help any.
Agreed. -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
