On Wed, Jun 10, 2015 at 12:42 PM, Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > On Wed, Jun 10, 2015 at 9:17 AM, Linus Torvalds > <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: >> >> So anyway, I like the patch series. I just think that the final patch >> - the one that actually saves the addreses, and limits things to >> BATCH_TLBFLUSH_SIZE, should be limited. > > Oh, and another thing: > > Mel, can you please make that "struct tlbflush_unmap_batch" be just > part of "struct task_struct" rather than a pointer? > > If you are worried about the cpumask size, you could use > > cpumask_var_t cpumask; > > and > > alloc_cpumask_var(..) > ... > free_cpumask_var(..) > > for that. > > That way, sane configurations never have the allocation cost. > > (Of course, sad to say, sane configurations are probably few and far > between. At least Fedora seems to ship with a kernel where NR_CPU's is > 1024 and thus CONFIG_CPUMASK_OFFSTACK=y. Oh well. What a waste of CPU > cycles that is..) The insane part being NR_CPUS = 1024? Or that to have said number requires cpumask being dynamically allocated to avoid stack overflow? (Or both I guess). josh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>