Hi Michael, Thanks for comment! On 2017/8/1 19:00, Michael Ellerman wrote: > Yisheng Xie <xieyisheng1@xxxxxxxxxx> writes: > >> When ioremap a 67112960 bytes vm_area with the vmallocinfo: >> [..] >> 0xec79b000-0xec7fa000 389120 ftl_add_mtd+0x4d0/0x754 pages=94 vmalloc >> 0xec800000-0xecbe1000 4067328 kbox_proc_mem_write+0x104/0x1c4 phys=8b520000 ioremap >> >> we get the result: >> 0xf1000000-0xf5001000 67112960 devm_ioremap+0x38/0x7c phys=40000000 ioremap >> >> For the align for ioremap must be less than '1 << IOREMAP_MAX_ORDER': >> if (flags & VM_IOREMAP) >> align = 1ul << clamp_t(int, get_count_order_long(size), >> PAGE_SHIFT, IOREMAP_MAX_ORDER); >> >> So it makes idiot like me a litter puzzle why jump the vm_area from >> 0xec800000-0xecbe1000 to 0xf1000000-0xf5001000, and leave >> 0xed000000-0xf1000000 as a big hole. >> >> This is to show all of vm_area, including which is freeing but still in >> vmap_area_list, to make it more clear about why we will get >> 0xf1000000-0xf5001000 int the above case. And we will get the >> vmallocinfo like: >> [..] >> 0xec79b000-0xec7fa000 389120 ftl_add_mtd+0x4d0/0x754 pages=94 vmalloc >> 0xec800000-0xecbe1000 4067328 kbox_proc_mem_write+0x104/0x1c4 phys=8b520000 ioremap >> [..] >> 0xece7c000-0xece7e000 8192 unpurged vm_area >> 0xece7e000-0xece83000 20480 vm_map_ram >> 0xf0099000-0xf00aa000 69632 vm_map_ram > > My vmallocinfo is full of these unpurged areas, should I be worried? The unpurged areas is a lazy free vm area, which maybe free at anytime. e.g. if the nr_lazy(count in pages) is bigger than lazy_max_pages(), these area will be purged and free. So I think you do not have worried about it. Thanks Yisheng Xie > > # grep -c "unpurged" /proc/vmallocinfo > 311 > > cheers > > . > -- 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>
