Messages in this thread | | | From | KOSAKI Motohiro <> | Subject | Re: [patch -mm] cpusets: add memory_slab_hardwall flag | Date | Mon, 9 Mar 2009 13:49:27 +0900 (JST) |
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> Adds a per-cpuset `memory_slab_hardwall' flag. > > The slab allocator interface for determining whether an object is allowed > is > > int current_cpuset_object_allowed(int node, gfp_t flags) > > This returns non-zero when the object is allowed, either because > current's cpuset does not have memory_slab_hardwall enabled or because > it allows allocation on the node. Otherwise, it returns zero. > > This interface is lockless because a task's cpuset can always be safely > dereferenced atomically. > > For slab, if the physical node id of the cpu cache is not from an > allowable node, the allocation will fail. If an allocation is targeted > for a node that is not allowed, we allocate from an appropriate one > instead of failing. > > For slob, if the page from the slob list is not from an allowable node, > we continue to scan for an appropriate slab. If none can be used, a new > slab is allocated. > > For slub, if the cpu slab is not from an allowable node, the partial list > is scanned for a replacement. If none can be used, a new slab is > allocated.
Hmmm, this description only explay how to implement this. but no explain why this patch is useful.
Could you please who and why need it?
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