xref: /openbmc/linux/fs/proc/meminfo.c (revision 2572f00d)
1 #include <linux/fs.h>
2 #include <linux/init.h>
3 #include <linux/kernel.h>
4 #include <linux/mm.h>
5 #include <linux/hugetlb.h>
6 #include <linux/mman.h>
7 #include <linux/mmzone.h>
8 #include <linux/proc_fs.h>
9 #include <linux/quicklist.h>
10 #include <linux/seq_file.h>
11 #include <linux/swap.h>
12 #include <linux/vmstat.h>
13 #include <linux/atomic.h>
14 #include <linux/vmalloc.h>
15 #ifdef CONFIG_CMA
16 #include <linux/cma.h>
17 #endif
18 #include <asm/page.h>
19 #include <asm/pgtable.h>
20 #include "internal.h"
21 
22 void __attribute__((weak)) arch_report_meminfo(struct seq_file *m)
23 {
24 }
25 
26 static int meminfo_proc_show(struct seq_file *m, void *v)
27 {
28 	struct sysinfo i;
29 	unsigned long committed;
30 	long cached;
31 	long available;
32 	unsigned long pagecache;
33 	unsigned long wmark_low = 0;
34 	unsigned long pages[NR_LRU_LISTS];
35 	struct zone *zone;
36 	int lru;
37 
38 /*
39  * display in kilobytes.
40  */
41 #define K(x) ((x) << (PAGE_SHIFT - 10))
42 	si_meminfo(&i);
43 	si_swapinfo(&i);
44 	committed = percpu_counter_read_positive(&vm_committed_as);
45 
46 	cached = global_page_state(NR_FILE_PAGES) -
47 			total_swapcache_pages() - i.bufferram;
48 	if (cached < 0)
49 		cached = 0;
50 
51 	for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++)
52 		pages[lru] = global_page_state(NR_LRU_BASE + lru);
53 
54 	for_each_zone(zone)
55 		wmark_low += zone->watermark[WMARK_LOW];
56 
57 	/*
58 	 * Estimate the amount of memory available for userspace allocations,
59 	 * without causing swapping.
60 	 *
61 	 * Free memory cannot be taken below the low watermark, before the
62 	 * system starts swapping.
63 	 */
64 	available = i.freeram - wmark_low;
65 
66 	/*
67 	 * Not all the page cache can be freed, otherwise the system will
68 	 * start swapping. Assume at least half of the page cache, or the
69 	 * low watermark worth of cache, needs to stay.
70 	 */
71 	pagecache = pages[LRU_ACTIVE_FILE] + pages[LRU_INACTIVE_FILE];
72 	pagecache -= min(pagecache / 2, wmark_low);
73 	available += pagecache;
74 
75 	/*
76 	 * Part of the reclaimable slab consists of items that are in use,
77 	 * and cannot be freed. Cap this estimate at the low watermark.
78 	 */
79 	available += global_page_state(NR_SLAB_RECLAIMABLE) -
80 		     min(global_page_state(NR_SLAB_RECLAIMABLE) / 2, wmark_low);
81 
82 	if (available < 0)
83 		available = 0;
84 
85 	/*
86 	 * Tagged format, for easy grepping and expansion.
87 	 */
88 	seq_printf(m,
89 		"MemTotal:       %8lu kB\n"
90 		"MemFree:        %8lu kB\n"
91 		"MemAvailable:   %8lu kB\n"
92 		"Buffers:        %8lu kB\n"
93 		"Cached:         %8lu kB\n"
94 		"SwapCached:     %8lu kB\n"
95 		"Active:         %8lu kB\n"
96 		"Inactive:       %8lu kB\n"
97 		"Active(anon):   %8lu kB\n"
98 		"Inactive(anon): %8lu kB\n"
99 		"Active(file):   %8lu kB\n"
100 		"Inactive(file): %8lu kB\n"
101 		"Unevictable:    %8lu kB\n"
102 		"Mlocked:        %8lu kB\n"
103 #ifdef CONFIG_HIGHMEM
104 		"HighTotal:      %8lu kB\n"
105 		"HighFree:       %8lu kB\n"
106 		"LowTotal:       %8lu kB\n"
107 		"LowFree:        %8lu kB\n"
108 #endif
109 #ifndef CONFIG_MMU
110 		"MmapCopy:       %8lu kB\n"
111 #endif
112 		"SwapTotal:      %8lu kB\n"
113 		"SwapFree:       %8lu kB\n"
114 		"Dirty:          %8lu kB\n"
115 		"Writeback:      %8lu kB\n"
116 		"AnonPages:      %8lu kB\n"
117 		"Mapped:         %8lu kB\n"
118 		"Shmem:          %8lu kB\n"
119 		"Slab:           %8lu kB\n"
120 		"SReclaimable:   %8lu kB\n"
121 		"SUnreclaim:     %8lu kB\n"
122 		"KernelStack:    %8lu kB\n"
123 		"PageTables:     %8lu kB\n"
124 #ifdef CONFIG_QUICKLIST
125 		"Quicklists:     %8lu kB\n"
126 #endif
127 		"NFS_Unstable:   %8lu kB\n"
128 		"Bounce:         %8lu kB\n"
129 		"WritebackTmp:   %8lu kB\n"
130 		"CommitLimit:    %8lu kB\n"
131 		"Committed_AS:   %8lu kB\n"
132 		"VmallocTotal:   %8lu kB\n"
133 		"VmallocUsed:    %8lu kB\n"
134 		"VmallocChunk:   %8lu kB\n"
135 #ifdef CONFIG_MEMORY_FAILURE
136 		"HardwareCorrupted: %5lu kB\n"
137 #endif
138 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
139 		"AnonHugePages:  %8lu kB\n"
140 #endif
141 #ifdef CONFIG_CMA
142 		"CmaTotal:       %8lu kB\n"
143 		"CmaFree:        %8lu kB\n"
144 #endif
145 		,
146 		K(i.totalram),
147 		K(i.freeram),
148 		K(available),
149 		K(i.bufferram),
150 		K(cached),
151 		K(total_swapcache_pages()),
152 		K(pages[LRU_ACTIVE_ANON]   + pages[LRU_ACTIVE_FILE]),
153 		K(pages[LRU_INACTIVE_ANON] + pages[LRU_INACTIVE_FILE]),
154 		K(pages[LRU_ACTIVE_ANON]),
155 		K(pages[LRU_INACTIVE_ANON]),
156 		K(pages[LRU_ACTIVE_FILE]),
157 		K(pages[LRU_INACTIVE_FILE]),
158 		K(pages[LRU_UNEVICTABLE]),
159 		K(global_page_state(NR_MLOCK)),
160 #ifdef CONFIG_HIGHMEM
161 		K(i.totalhigh),
162 		K(i.freehigh),
163 		K(i.totalram-i.totalhigh),
164 		K(i.freeram-i.freehigh),
165 #endif
166 #ifndef CONFIG_MMU
167 		K((unsigned long) atomic_long_read(&mmap_pages_allocated)),
168 #endif
169 		K(i.totalswap),
170 		K(i.freeswap),
171 		K(global_page_state(NR_FILE_DIRTY)),
172 		K(global_page_state(NR_WRITEBACK)),
173 		K(global_page_state(NR_ANON_PAGES)),
174 		K(global_page_state(NR_FILE_MAPPED)),
175 		K(i.sharedram),
176 		K(global_page_state(NR_SLAB_RECLAIMABLE) +
177 				global_page_state(NR_SLAB_UNRECLAIMABLE)),
178 		K(global_page_state(NR_SLAB_RECLAIMABLE)),
179 		K(global_page_state(NR_SLAB_UNRECLAIMABLE)),
180 		global_page_state(NR_KERNEL_STACK) * THREAD_SIZE / 1024,
181 		K(global_page_state(NR_PAGETABLE)),
182 #ifdef CONFIG_QUICKLIST
183 		K(quicklist_total_size()),
184 #endif
185 		K(global_page_state(NR_UNSTABLE_NFS)),
186 		K(global_page_state(NR_BOUNCE)),
187 		K(global_page_state(NR_WRITEBACK_TEMP)),
188 		K(vm_commit_limit()),
189 		K(committed),
190 		(unsigned long)VMALLOC_TOTAL >> 10,
191 		0ul, // used to be vmalloc 'used'
192 		0ul  // used to be vmalloc 'largest_chunk'
193 #ifdef CONFIG_MEMORY_FAILURE
194 		, atomic_long_read(&num_poisoned_pages) << (PAGE_SHIFT - 10)
195 #endif
196 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
197 		, K(global_page_state(NR_ANON_TRANSPARENT_HUGEPAGES) *
198 		   HPAGE_PMD_NR)
199 #endif
200 #ifdef CONFIG_CMA
201 		, K(totalcma_pages)
202 		, K(global_page_state(NR_FREE_CMA_PAGES))
203 #endif
204 		);
205 
206 	hugetlb_report_meminfo(m);
207 
208 	arch_report_meminfo(m);
209 
210 	return 0;
211 #undef K
212 }
213 
214 static int meminfo_proc_open(struct inode *inode, struct file *file)
215 {
216 	return single_open(file, meminfo_proc_show, NULL);
217 }
218 
219 static const struct file_operations meminfo_proc_fops = {
220 	.open		= meminfo_proc_open,
221 	.read		= seq_read,
222 	.llseek		= seq_lseek,
223 	.release	= single_release,
224 };
225 
226 static int __init proc_meminfo_init(void)
227 {
228 	proc_create("meminfo", 0, NULL, &meminfo_proc_fops);
229 	return 0;
230 }
231 fs_initcall(proc_meminfo_init);
232