xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/set_mempolicy/set_mempolicy04.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2018 Cyril Hrubis <[email protected]>
4  */
5 
6 /*
7  * We are testing set_mempolicy() with MPOL_INTERLEAVE on mmaped buffers backed
8  * by files.
9  *
10  * Apparently it takes a larger sample for the allocations to be correctly
11  * interleaved. The reason for this is that buffers for file metadata are
12  * allocated in batches in order not to loose performance. Also the pages
13  * cannot be interleaved completely evenly unless the number of pages is
14  * divideable by the number of nodes, which will not happen even if we tried
15  * hard since we do not have controll over metadata blocks for instance. Hence
16  * we cannot really expect to allocate a single file and have the memory
17  * interleaved precisely but it works well if we allocate statistic for a more
18  * than a few files.
19  */
20 
21 #include <stdio.h>
22 #include <errno.h>
23 #include "config.h"
24 #ifdef HAVE_NUMA_V2
25 # include <numa.h>
26 # include <numaif.h>
27 #endif
28 #include "tst_test.h"
29 #include "tst_numa.h"
30 
31 #define MNTPOINT "mntpoint"
32 #define FILES 10
33 
34 #ifdef HAVE_NUMA_V2
35 
36 #include "set_mempolicy.h"
37 
38 static size_t page_size;
39 static struct tst_nodemap *nodes;
40 
setup(void)41 static void setup(void)
42 {
43 	int node_min_pages = FILES * (FILES + 1) / 2 * 10 + FILES * 10;
44 
45 	page_size = getpagesize();
46 
47 	nodes = tst_get_nodemap(TST_NUMA_MEM, node_min_pages * page_size / 1024);
48 	if (nodes->cnt <= 1)
49 		tst_brk(TCONF, "Test requires at least two NUMA memory nodes");
50 }
51 
cleanup(void)52 static void cleanup(void)
53 {
54 	tst_nodemap_free(nodes);
55 }
56 
alloc_and_check(void)57 static void alloc_and_check(void)
58 {
59 	unsigned int i, j;
60 	char path[1024];
61 	unsigned int total_pages = 0;
62 	unsigned int sum_pages = 0;
63 
64 	tst_nodemap_reset_counters(nodes);
65 
66 	/*
67 	 * The inner loop loops node->cnt times to ensure the sum could
68 	 * be evenly distributed among the nodes.
69 	 */
70 	for (i = 1; i <= FILES; i++) {
71 		for (j = 1; j <= nodes->cnt; j++) {
72 			size_t size = 10 * i + j % 10;
73 			snprintf(path, sizeof(path), MNTPOINT "/numa-test-file-%i-%i", i, j);
74 			alloc_fault_count(nodes, path, size * page_size);
75 			total_pages += size;
76 		}
77 	}
78 
79 	for (i = 0; i < nodes->cnt; i++) {
80 		float treshold = 1.00 * total_pages / 60; /* five percents */
81 		float min_pages = 1.00 * total_pages / nodes->cnt - treshold;
82 		float max_pages = 1.00 * total_pages / nodes->cnt + treshold;
83 
84 		if (nodes->counters[i] > min_pages && nodes->counters[i] < max_pages) {
85 			tst_res(TPASS, "Node %u allocated %u <%.2f,%.2f>",
86 			        nodes->map[i], nodes->counters[i], min_pages, max_pages);
87 		} else {
88 			tst_res(TFAIL, "Node %u allocated %u, expected <%.2f,%.2f>",
89 			        nodes->map[i], nodes->counters[i], min_pages, max_pages);
90 		}
91 
92 		sum_pages += nodes->counters[i];
93 	}
94 
95 	if (sum_pages != total_pages) {
96 		tst_res(TFAIL, "Sum of nodes %u != allocated pages %u",
97 		        sum_pages, total_pages);
98 		return;
99 	}
100 
101 	tst_res(TPASS, "Sum of nodes equals to allocated pages (%u)", total_pages);
102 }
103 
verify_set_mempolicy(void)104 static void verify_set_mempolicy(void)
105 {
106 	struct bitmask *bm = numa_allocate_nodemask();
107 	unsigned int alloc_on_nodes = nodes->cnt;
108 	unsigned int i;
109 
110 	for (i = 0; i < alloc_on_nodes; i++)
111 		numa_bitmask_setbit(bm, nodes->map[i]);
112 
113 	TEST(set_mempolicy(MPOL_INTERLEAVE, bm->maskp, bm->size+1));
114 
115 	if (TST_RET) {
116 		tst_res(TFAIL | TTERRNO,
117 		        "set_mempolicy(MPOL_INTERLEAVE)");
118 		return;
119 	}
120 
121 	tst_res(TPASS, "set_mempolicy(MPOL_INTERLEAVE)");
122 
123 	alloc_and_check();
124 
125 	numa_free_nodemask(bm);
126 }
127 
128 static struct tst_test test = {
129 	.setup = setup,
130 	.cleanup = cleanup,
131 	.test_all = verify_set_mempolicy,
132 	.forks_child = 1,
133 	.needs_root = 1,
134 	.all_filesystems = 1,
135 	.mntpoint = MNTPOINT,
136 	.needs_checkpoints = 1,
137 };
138 
139 #else
140 
141 TST_TEST_TCONF(NUMA_ERROR_MSG);
142 
143 #endif /* HAVE_NUMA_V2 */
144