1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_MM_TYPES_TASK_H
3#define _LINUX_MM_TYPES_TASK_H
4
5/*
6 * Here are the definitions of the MM data types that are embedded in 'struct task_struct'.
7 *
8 * (These are defined separately to decouple sched.h from mm_types.h as much as possible.)
9 */
10
11#include <linux/types.h>
12#include <linux/threads.h>
13#include <linux/atomic.h>
14#include <linux/cpumask.h>
15
16#include <asm/page.h>
17
18#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
19#include <asm/tlbbatch.h>
20#endif
21
22#define USE_SPLIT_PTE_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
23#define USE_SPLIT_PMD_PTLOCKS (USE_SPLIT_PTE_PTLOCKS && \
24 IS_ENABLED(CONFIG_ARCH_ENABLE_SPLIT_PMD_PTLOCK))
25#define ALLOC_SPLIT_PTLOCKS (SPINLOCK_SIZE > BITS_PER_LONG/8)
26
27/*
28 * The per task VMA cache array:
29 */
30#define VMACACHE_BITS 2
31#define VMACACHE_SIZE (1U << VMACACHE_BITS)
32#define VMACACHE_MASK (VMACACHE_SIZE - 1)
33
34struct vmacache {
35 u64 seqnum;
36 struct vm_area_struct *vmas[VMACACHE_SIZE];
37};
38
39/*
40 * When updating this, please also update struct resident_page_types[] in
41 * kernel/fork.c
42 */
43enum {
44 MM_FILEPAGES, /* Resident file mapping pages */
45 MM_ANONPAGES, /* Resident anonymous pages */
46 MM_SWAPENTS, /* Anonymous swap entries */
47 MM_SHMEMPAGES, /* Resident shared memory pages */
48 NR_MM_COUNTERS
49};
50
51#if USE_SPLIT_PTE_PTLOCKS && defined(CONFIG_MMU)
52#define SPLIT_RSS_COUNTING
53/* per-thread cached information, */
54struct task_rss_stat {
55 int events; /* for synchronization threshold */
56 int count[NR_MM_COUNTERS];
57};
58#endif /* USE_SPLIT_PTE_PTLOCKS */
59
60struct mm_rss_stat {
61 atomic_long_t count[NR_MM_COUNTERS];
62};
63
64struct page_frag {
65 struct page *page;
66#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
67 __u32 offset;
68 __u32 size;
69#else
70 __u16 offset;
71 __u16 size;
72#endif
73};
74
75/* Track pages that require TLB flushes */
76struct tlbflush_unmap_batch {
77#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
78 /*
79 * The arch code makes the following promise: generic code can modify a
80 * PTE, then call arch_tlbbatch_add_mm() (which internally provides all
81 * needed barriers), then call arch_tlbbatch_flush(), and the entries
82 * will be flushed on all CPUs by the time that arch_tlbbatch_flush()
83 * returns.
84 */
85 struct arch_tlbflush_unmap_batch arch;
86
87 /* True if a flush is needed. */
88 bool flush_required;
89
90 /*
91 * If true then the PTE was dirty when unmapped. The entry must be
92 * flushed before IO is initiated or a stale TLB entry potentially
93 * allows an update without redirtying the page.
94 */
95 bool writable;
96#endif
97};
98
99#endif /* _LINUX_MM_TYPES_TASK_H */
100

source code of linux/include/linux/mm_types_task.h