On 2015/4/20 11:15, Yasuaki Ishimatsu wrote: > > On Mon, 20 Apr 2015 10:59:37 +0800 > Xishi Qiu <qiuxi...@huawei.com> wrote: > >> On 2015/4/20 10:09, Gu Zheng wrote: >> >>> Hi Ishimatsu, Xishi, >>> >>> On 04/20/2015 10:11 AM, Yasuaki Ishimatsu wrote: >>> >>>> >>>>> When hot adding memory and creating new node, the node is offline. >>>>> And after calling node_set_online(), the node becomes online. >>>>> >>>>> Oh, sorry. I misread your ptaches. >>>>> >>>> >>>> Please ignore it... >>> >>> Seems also a misread to me. >>> I clear it (my worry) here: >>> If we set the node size to 0 here, it may hidden more things than we >>> experted. >>> All the init chunks around with the size (spanned/present/managed...) will >>> be non-sense, and the user/caller will not get a summary of the hot added >>> node >>> because of the changes here. >>> I am not sure the worry is necessary, please correct me if I missing >>> something. >>> >>> Regards, >>> Gu >>> >> >> Hi Gu, >> >> My patch is just set size to 0 when hotadd a node(old or new). I know your >> worry, >> but I think it is not necessary. >> > >> When we calculate the size, it uses "arch_zone_lowest_possible_pfn[]" and >> "memblock", >> and they are both from boot time. If we hotadd a new node, the calculated >> size is >> 0 too. When add momery, __add_zone() will grow the size and start. > > If hot adding new node, you are right. But if hot removing a memory which > is presented at boot time, memblock of the memory range is not deleted. > So when hot adding the memory, the calculated size does not become 0. >
Yes, so I just set it to 0, init_currently_empty_zone() and memmap_init() will be called in __add_zone(), and start/size also will be grow there. Thanks, Xishi Qiu > Thanks, > Yasuaki Ishimatsu > >> >> Thanks, >> Xishi Qiu >> > > . > -- 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/
