On 27/03/13 13:57, Chris Ball wrote: > Hi, > > On Wed, Mar 27 2013, Ulf Hansson wrote: >> I noticed you merged this. I thought the idea was to use the rootwait >> or rootdelay? > > That's necessary before the patch, but it would be better if we didn't > have to pass rootwait, all else being equal. > >> Moreover, this patch will have bad impact on booting the kernel, since >> every host device that has scheduled a detect work from it's probe >> function will also wait for it to finish. Even if it is the boot >> device of not. If this is needed, I would prefer that a host cap is >> used. > > I see, you're worried about a performance regression where every boot > takes longer than it used to while MMC quiesces. That's fair. Do you > think you could tell me how much delay this adds to a boot for you, so > that we can consider whether the usability improvement is worth it? > > If the delay's significant, I agree with you and will revert this patch. On my system it is significant: Before the patch: [ 1.625623] VFS: Mounted root (ext4 filesystem) readonly on device 179:2. After the patch: [ 1.935851] VFS: Mounted root (ext4 filesystem) readonly on device 179:2. That is an addition of 310 ms which is 19% performance degradation. Please revert the patch. -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
