Hi > On Tue, 12 Apr 2011, KOSAKI Motohiro wrote: > > > > Benjamin, Hugh, I hope to add your S-O-B to this one because you are original author. > > Can I do? > > Well, now you've fixed the mm/fremap.c omission, you're welcome to my > Acked-by: Hugh Dickins <hughd@xxxxxxxxxx> Thank you! > I happen not to shared Ben's aversion to unsigned long long, I just > don't really care one way or another on that; but I do get irritated by > obfuscatory types which we then have to cast or unfold all over the place, > I don't know if vm_flags_t would have been in that category or not. I agree. > You've made a few different choices than I did, okay: the only place > where it might be worth disagreeing with you, is on mm->def_flags: > I would rather make that an unsigned int than an unsigned long long, > to save 4 bytes on 64-bit (if it were moved) rather than waste 4 bytes > on 32-bit - in the unlikely event that someone adds a high VM_flag to > def_flags, I'd rather hope they would test its effect. However, > it's every mm not every vma, so maybe not worth worrying about. Yeap. I thought it is one of typical easy-read-code vs memory-footprint trade-off. And after I looked size of task_struct, I was lost interest to spned my time to keep small mm_struct size. ;-) off-topic, if mm_struct size is performance important, we have to get rid of mm->cpu_vm_mask from mm_struct at first. cpumask_t use NR_CPUS/8 bytes and NR_CPUS==4096 when we use recent distros. it's one of root cause of mm_struct bloat. > I am surprised that > #define VM_EXEC 0x00000004ULL > does not cause trouble for arch/arm/kernel/asm-offsets.c, > but you tried cross-building it which I never did. > > Does your later addition of __nocast on vm_flags not make trouble > for the unsigned long casts in arch/arm/include/asm/cacheflush.h? > (And if it does not, then just what does __nocast do?) If my understanding is correct, __nocast mean warn _implicit_ narrowing conversion. Thus, arm defconfig cross build doesn't make any warn nor error. :) side note: honestly says, I know arm defconfig doesn't build many subarch specific cacheflush code. But I have no way to confirm it. ;) > > Thanks for seeing this through, > Hugh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>