On Wed, 2013-08-21 at 14:32 +0000, Christoph Lameter wrote: > On Tue, 20 Aug 2013, Nicholas A. Bellinger wrote: > > > On Thu, 2013-08-08 at 14:32 +0000, Christoph Lameter wrote: > > > On Wed, 7 Aug 2013, Kent Overstreet wrote: > > > > > > > One thing that was bugging me - I was never able to figure out for sure > > > > if smp_processor_id() returns a number in the range [0, nr_cpu_ids), at > > > > least I couldn't find where it was documented - could you tell me if > > > > that's true? > > > > > > I always assumed that it was in the range 0 ... nr_cpu_ids - 1 and that is > > > the assumption under which the kernel code was written. Things would break > > > horribly if smp_process_id would return nr_cpu_ids or higher. > > > > > > > Hi guys, > > > > Just a heads up that I've put Kent's standalone percpu-ida patch (with > > Christoph's recommend changes) into target-pending/for-next here: > > > > https://git.kernel.org/cgit/linux/kernel/git/nab/target-pending.git/commit/?h=for-next&id=47bd524a5b3eb6429b058b8b562b45329ab2c9e7 > > > > I've got a number of target patches that depend on this code for v3.12, > > and a delay on this particular piece would be painful to endure.. > > > > Sooo, please yell loudly if there is an objection to percpu-ida merge as > > a completely standalone item, that does not effect any existing ida > > code. > > Well the performance is still going to be limited due to the spinlock in > the percpu handling. You do not need the spinlock. Once preempt is off you > should have exclusive access to the per cpu data. This is already > exploited by idr_layer_alloc before the patch. Doing so is going to > reduce the code size of the patch significantly. > > Please post the patch inline so that its easy to comment on it. >
Hi Christoph, The latest version from Kent was posted last week here: http://marc.info/?l=linux-kernel&m=137669878117020&w=2 --nab -- 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/