Re: [opensuse-arm] CONFIG_PREEMPT for ARM boards?

On 11.10.2012, at 18:46, guillaume.gardet@free.fr wrote:

----- Alexander Graf a écrit :

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On 11.10.2012, at 17:45, Guillaume Gardet wrote:

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Hi,

Does anybody thought about kernel preemption for ARM boards? It could be usefull since kernel preemption is intended to embedded system or (Low-latency) Desktop.

Moreover, If we want to enable openGL on omap4 (pandaboard), we need a preemptible kernel.

Why?

It is a build requirement, otherwise, we get: [ 664s] /home/abuild/rpmbuild/BUILD/pvr-omap4-kernel-1330667111/sgx/eurasiacon/binary2_omap4430_linux_release/target/kbuild/services4/srvkm/env/linux/osfunc.c:85:2: error: #error "A preemptible Linux kernel is required when using workqueues"

That sounds very very wrong :).

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Is there any objection to move to a preemptible kernel for omap2plus? For other ARM boards? For Factory and/or 12.2?

It usually incurs overhead for not too much perceivable gain. Have you run into latency issues?

No, but it may be useful for people using sound or things like that which need low latency.

Well, we can switch _all_ our kernels to PREEMPT_VOLUNTARY. Alex -- To unsubscribe, e-mail: opensuse-arm+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-arm+owner@opensuse.org