From: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx> Subject: selftest/vm: fix ksm selftest to run with different NUMA topologies Platforms can have non-contiguous NUMA nodes like below #numactl -H available: 2 nodes (0,8) ..... node distances: node 0 8 0: 10 40 8: 40 10 #numactl -H available: 1 nodes (1) .... node distances: node 1 1: 10 Hence update the test to not assume the presence of Node 0 and 1 and also use numa_num_configured_nodes() instead of numa_max_node for finding whether to skip the test. Link: https://lkml.kernel.org/r/20210914141414.350759-1-aneesh.kumar@xxxxxxxxxxxxx Fixes: 82e717ad3501 ("selftests: vm: add KSM merging across nodes test") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx> Reviewed-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Zhansaya Bagdauletkyzy <zhansayabagdaulet@xxxxxxxxx> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Tyler Hicks <tyhicks@xxxxxxxxxxxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/vm/ksm_tests.c | 29 ++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-) --- a/tools/testing/selftests/vm/ksm_tests.c~selftest-vm-fix-ksm-selftest-to-run-with-different-numa-topologies +++ a/tools/testing/selftests/vm/ksm_tests.c @@ -354,12 +354,34 @@ err_out: return KSFT_FAIL; } +static int get_next_mem_node(int node) +{ + + long node_size; + int mem_node = 0; + int i, max_node = numa_max_node(); + + for (i = node + 1; i <= max_node + node; i++) { + mem_node = i % (max_node + 1); + node_size = numa_node_size(mem_node, NULL); + if (node_size > 0) + break; + } + return mem_node; +} + +static int get_first_mem_node(void) +{ + return get_next_mem_node(numa_max_node()); +} + static int check_ksm_numa_merge(int mapping, int prot, int timeout, bool merge_across_nodes, size_t page_size) { void *numa1_map_ptr, *numa2_map_ptr; struct timespec start_time; int page_count = 2; + int first_node; if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) { perror("clock_gettime"); @@ -370,7 +392,7 @@ static int check_ksm_numa_merge(int mapp perror("NUMA support not enabled"); return KSFT_SKIP; } - if (numa_max_node() < 1) { + if (numa_num_configured_nodes() <= 1) { printf("At least 2 NUMA nodes must be available\n"); return KSFT_SKIP; } @@ -378,8 +400,9 @@ static int check_ksm_numa_merge(int mapp return KSFT_FAIL; /* allocate 2 pages in 2 different NUMA nodes and fill them with the same data */ - numa1_map_ptr = numa_alloc_onnode(page_size, 0); - numa2_map_ptr = numa_alloc_onnode(page_size, 1); + first_node = get_first_mem_node(); + numa1_map_ptr = numa_alloc_onnode(page_size, first_node); + numa2_map_ptr = numa_alloc_onnode(page_size, get_next_mem_node(first_node)); if (!numa1_map_ptr || !numa2_map_ptr) { perror("numa_alloc_onnode"); return KSFT_FAIL; _