Hello Zhenguo Yao,
The patch 67b2b441dc10: "hugetlbfs: extend the definition of
hugepages parameter to support node allocation" from Sep 29, 2021,
leads to the following
Smatch static checker warning:
mm/hugetlb.c:2957 __alloc_bootmem_huge_page()
warn: ignoring unreachable code.
mm/hugetlb.c
2940 int __alloc_bootmem_huge_page(struct hstate *h, int nid)
2941 {
2942 struct huge_bootmem_page *m;
2943 int nr_nodes, node;
2944
2945 if (nid >= nr_online_nodes)
2946 return 0;
2947 /* do node specific alloc */
2948 if (nid != NUMA_NO_NODE) {
2949 m = memblock_alloc_try_nid_raw(huge_page_size(h), huge_page_size(h),
2950 0, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
2951 if (m)
2952 goto found;
2953 else
2954 return 0;
2955 }
2956 /* do all node balanced alloc */
^^^^^^^^
This says that it's going to loop over "all nodes".
--> 2957 for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) {
2958 m = memblock_alloc_try_nid_raw(
2959 huge_page_size(h), huge_page_size(h),
2960 0, MEMBLOCK_ALLOC_ACCESSIBLE, node);
2961 /*
2962 * Use the beginning of the huge page to store the
2963 * huge_bootmem_page struct (until gather_bootmem
2964 * puts them into the mem_map).
2965 */
2966 if (m)
2967 goto found;
2968 else
2969 return 0;
But it only checks the first node and then returns.
2970 }
2971
2972 found:
2973 /* Put them into a private list first because mem_map is not up yet */
2974 INIT_LIST_HEAD(&m->list);
2975 list_add(&m->list, &huge_boot_pages);
2976 m->hstate = h;
2977 return 1;
2978 }
regards,
dan carpenter
