xref: /linux/mm/debug.c (revision f79e4d5f92a129a1159c973735007d4ddc8541f3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * mm/debug.c
4  *
5  * mm/ specific debug routines.
6  *
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/mm.h>
11 #include <linux/trace_events.h>
12 #include <linux/memcontrol.h>
13 #include <trace/events/mmflags.h>
14 #include <linux/migrate.h>
15 #include <linux/page_owner.h>
16 
17 #include "internal.h"
18 
19 char *migrate_reason_names[MR_TYPES] = {
20 	"compaction",
21 	"memory_failure",
22 	"memory_hotplug",
23 	"syscall_or_cpuset",
24 	"mempolicy_mbind",
25 	"numa_misplaced",
26 	"cma",
27 };
28 
29 const struct trace_print_flags pageflag_names[] = {
30 	__def_pageflag_names,
31 	{0, NULL}
32 };
33 
34 const struct trace_print_flags gfpflag_names[] = {
35 	__def_gfpflag_names,
36 	{0, NULL}
37 };
38 
39 const struct trace_print_flags vmaflag_names[] = {
40 	__def_vmaflag_names,
41 	{0, NULL}
42 };
43 
44 void __dump_page(struct page *page, const char *reason)
45 {
46 	bool page_poisoned = PagePoisoned(page);
47 	int mapcount;
48 
49 	/*
50 	 * If struct page is poisoned don't access Page*() functions as that
51 	 * leads to recursive loop. Page*() check for poisoned pages, and calls
52 	 * dump_page() when detected.
53 	 */
54 	if (page_poisoned) {
55 		pr_emerg("page:%px is uninitialized and poisoned", page);
56 		goto hex_only;
57 	}
58 
59 	/*
60 	 * Avoid VM_BUG_ON() in page_mapcount().
61 	 * page->_mapcount space in struct page is used by sl[aou]b pages to
62 	 * encode own info.
63 	 */
64 	mapcount = PageSlab(page) ? 0 : page_mapcount(page);
65 
66 	pr_emerg("page:%px count:%d mapcount:%d mapping:%px index:%#lx",
67 		  page, page_ref_count(page), mapcount,
68 		  page->mapping, page_to_pgoff(page));
69 	if (PageCompound(page))
70 		pr_cont(" compound_mapcount: %d", compound_mapcount(page));
71 	pr_cont("\n");
72 	BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
73 
74 	pr_emerg("flags: %#lx(%pGp)\n", page->flags, &page->flags);
75 
76 hex_only:
77 	print_hex_dump(KERN_ALERT, "raw: ", DUMP_PREFIX_NONE, 32,
78 			sizeof(unsigned long), page,
79 			sizeof(struct page), false);
80 
81 	if (reason)
82 		pr_alert("page dumped because: %s\n", reason);
83 
84 #ifdef CONFIG_MEMCG
85 	if (!page_poisoned && page->mem_cgroup)
86 		pr_alert("page->mem_cgroup:%px\n", page->mem_cgroup);
87 #endif
88 }
89 
90 void dump_page(struct page *page, const char *reason)
91 {
92 	__dump_page(page, reason);
93 	dump_page_owner(page);
94 }
95 EXPORT_SYMBOL(dump_page);
96 
97 #ifdef CONFIG_DEBUG_VM
98 
99 void dump_vma(const struct vm_area_struct *vma)
100 {
101 	pr_emerg("vma %px start %px end %px\n"
102 		"next %px prev %px mm %px\n"
103 		"prot %lx anon_vma %px vm_ops %px\n"
104 		"pgoff %lx file %px private_data %px\n"
105 		"flags: %#lx(%pGv)\n",
106 		vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_next,
107 		vma->vm_prev, vma->vm_mm,
108 		(unsigned long)pgprot_val(vma->vm_page_prot),
109 		vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
110 		vma->vm_file, vma->vm_private_data,
111 		vma->vm_flags, &vma->vm_flags);
112 }
113 EXPORT_SYMBOL(dump_vma);
114 
115 void dump_mm(const struct mm_struct *mm)
116 {
117 	pr_emerg("mm %px mmap %px seqnum %d task_size %lu\n"
118 #ifdef CONFIG_MMU
119 		"get_unmapped_area %px\n"
120 #endif
121 		"mmap_base %lu mmap_legacy_base %lu highest_vm_end %lu\n"
122 		"pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
123 		"hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
124 		"pinned_vm %lx data_vm %lx exec_vm %lx stack_vm %lx\n"
125 		"start_code %lx end_code %lx start_data %lx end_data %lx\n"
126 		"start_brk %lx brk %lx start_stack %lx\n"
127 		"arg_start %lx arg_end %lx env_start %lx env_end %lx\n"
128 		"binfmt %px flags %lx core_state %px\n"
129 #ifdef CONFIG_AIO
130 		"ioctx_table %px\n"
131 #endif
132 #ifdef CONFIG_MEMCG
133 		"owner %px "
134 #endif
135 		"exe_file %px\n"
136 #ifdef CONFIG_MMU_NOTIFIER
137 		"mmu_notifier_mm %px\n"
138 #endif
139 #ifdef CONFIG_NUMA_BALANCING
140 		"numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
141 #endif
142 		"tlb_flush_pending %d\n"
143 		"def_flags: %#lx(%pGv)\n",
144 
145 		mm, mm->mmap, mm->vmacache_seqnum, mm->task_size,
146 #ifdef CONFIG_MMU
147 		mm->get_unmapped_area,
148 #endif
149 		mm->mmap_base, mm->mmap_legacy_base, mm->highest_vm_end,
150 		mm->pgd, atomic_read(&mm->mm_users),
151 		atomic_read(&mm->mm_count),
152 		mm_pgtables_bytes(mm),
153 		mm->map_count,
154 		mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,
155 		mm->pinned_vm, mm->data_vm, mm->exec_vm, mm->stack_vm,
156 		mm->start_code, mm->end_code, mm->start_data, mm->end_data,
157 		mm->start_brk, mm->brk, mm->start_stack,
158 		mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,
159 		mm->binfmt, mm->flags, mm->core_state,
160 #ifdef CONFIG_AIO
161 		mm->ioctx_table,
162 #endif
163 #ifdef CONFIG_MEMCG
164 		mm->owner,
165 #endif
166 		mm->exe_file,
167 #ifdef CONFIG_MMU_NOTIFIER
168 		mm->mmu_notifier_mm,
169 #endif
170 #ifdef CONFIG_NUMA_BALANCING
171 		mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
172 #endif
173 		atomic_read(&mm->tlb_flush_pending),
174 		mm->def_flags, &mm->def_flags
175 	);
176 }
177 
178 #endif		/* CONFIG_DEBUG_VM */
179