Hi Hanjun, Rafael, On 04/25/2015 06:14 PM, Hanjun Guo wrote: > On 2015/4/24 22:45, Rafael J. Wysocki wrote: >> On Friday, April 24, 2015 05:58:32 PM Gu Zheng wrote: >>> Yasuaki Ishimatsu found that with node online/offline, cpu<->node relationship >>> is established. Because workqueue uses a info which was established at boot >>> time, but it may be changed by node hotpluging. >>> >>> Once pool->node points to a stale node, following allocation failure >>> happens. >>> == >>> SLUB: Unable to allocate memory on node 2 (gfp=0x80d0) >>> cache: kmalloc-192, object size: 192, buffer size: 192, default >>> order: >>> 1, min order: 0 >>> node 0: slabs: 6172, objs: 259224, free: 245741 >>> node 1: slabs: 3261, objs: 136962, free: 127656 >>> == >>> >>> As the apicid <---> pxm and pxm <--> node relationship are persistent, then >>> the apicid <--> node mapping is persistent, so the root cause is the >>> cpu-id <-> lapicid mapping is not persistent (because the currently implementation >>> always choose the first free cpu id for the new added cpu). If we can build >>> persistent cpu-id <-> lapicid relationship, this problem will be fixed. >>> >>> This patch tries to build the whole world mapping cpuid <-> apicid <-> pxm <-> node >>> for all possible processor at the boot, the detail implementation are 2 steps: >>> Step1: generate a logic cpu id for all the local apic (both enabled and dsiabled) >>> when register local apic >>> Step2: map the cpu to the phyical node via an additional acpi ns walk for processor. >>> >>> Please refer to: >>> https://lkml.org/lkml/2015/2/27/145 >>> https://lkml.org/lkml/2015/3/25/989 >>> for the previous discussion. >>> >>> Reported-by: Yasuaki Ishimatsu <isimatu.yasuaki@xxxxxxxxxxxxxx> >>> Signed-off-by: Gu Zheng <guz.fnst@xxxxxxxxxxxxxx> >> This one will conflict with the ARM64 ACPI material when that goes in, so it'll >> need to be rebased on top of that. > > Yes, please. Then I will take a look too. Thanks for your reminder, will rebase it soon. Regards, Gu > > Thanks > Hanjun > > . > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
