(2012/06/13 8:13), Andi Kleen wrote: > From: Andi Kleen<ak@xxxxxxxxxxxxxxx> > > There was some desire in large applications using MAP_HUGETLB/SHM_HUGETLB > to use 1GB huge pages on some mappings, and stay with 2MB on others. This > is useful together with NUMA policy: use 2MB interleaving on some mappings, > but 1GB on local mappings. > > This patch extends the IPC/SHM syscall interfaces slightly to allow specifying > the page size. > > It borrows some upper bits in the existing flag arguments and allows encoding > the log of the desired page size in addition to the *_HUGETLB flag. > When 0 is specified the default size is used, this makes the change fully > compatible. > > Extending the internal hugetlb code to handle this is straight forward. Instead > of a single mount it just keeps an array of them and selects the right > mount based on the specified page size. > > I also exported the new flags to the user headers > (they were previously under __KERNEL__). Right now only symbols > for x86 and some other architecture for 1GB and 2MB are defined. > The interface should already work for all other architectures > though. > > v2: Port to new tree. Fix unmount. > Signed-off-by: Andi Kleen<ak@xxxxxxxxxxxxxxx> I like this. Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> BTW, do you have any plan to implement 1GB page allocator ? I wonder recent contiguous-memory-allocator works can be used for... -- 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>