Add zero_buffers option
[fio.git] / memory.c
... / ...
CommitLineData
1/*
2 * Memory helpers
3 */
4#include <unistd.h>
5#include <sys/shm.h>
6#include <sys/mman.h>
7
8#include "fio.h"
9
10static void *pinned_mem;
11
12void fio_unpin_memory(void)
13{
14 if (pinned_mem) {
15 if (munlock(pinned_mem, mlock_size) < 0)
16 perror("munlock");
17 munmap(pinned_mem, mlock_size);
18 pinned_mem = NULL;
19 }
20}
21
22int fio_pin_memory(void)
23{
24 unsigned long long phys_mem;
25
26 if (!mlock_size)
27 return 0;
28
29 /*
30 * Don't allow mlock of more than real_mem-128MB
31 */
32 phys_mem = os_phys_mem();
33 if (phys_mem) {
34 if ((mlock_size + 128 * 1024 * 1024) > phys_mem) {
35 mlock_size = phys_mem - 128 * 1024 * 1024;
36 log_info("fio: limiting mlocked memory to %lluMiB\n", mlock_size >> 20);
37 }
38 }
39
40 pinned_mem = mmap(NULL, mlock_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | OS_MAP_ANON, 0, 0);
41 if (pinned_mem == MAP_FAILED) {
42 perror("malloc locked mem");
43 pinned_mem = NULL;
44 return 1;
45 }
46 if (mlock(pinned_mem, mlock_size) < 0) {
47 perror("mlock");
48 munmap(pinned_mem, mlock_size);
49 pinned_mem = NULL;
50 return 1;
51 }
52
53 return 0;
54}
55
56/*
57 * Setup the buffer area we need for io.
58 */
59int allocate_io_mem(struct thread_data *td)
60{
61 if (td->o.mem_type == MEM_MALLOC)
62 td->orig_buffer = malloc(td->orig_buffer_size);
63 else if (td->o.mem_type == MEM_SHM || td->o.mem_type == MEM_SHMHUGE) {
64 int flags = IPC_CREAT | SHM_R | SHM_W;
65
66 if (td->o.mem_type == MEM_SHMHUGE)
67 flags |= SHM_HUGETLB;
68
69 td->shm_id = shmget(IPC_PRIVATE, td->orig_buffer_size, flags);
70 if (td->shm_id < 0) {
71 td_verror(td, errno, "shmget");
72 if (geteuid() != 0 && errno == ENOMEM)
73 log_err("fio: you may need to run this job as root\n");
74 if (errno == EINVAL && td->o.mem_type == MEM_SHMHUGE)
75 log_err("fio: check that you have free huge pages and that hugepage-size is correct.\n");
76
77 return 1;
78 }
79
80 td->orig_buffer = shmat(td->shm_id, NULL, 0);
81 if (td->orig_buffer == (void *) -1) {
82 td_verror(td, errno, "shmat");
83 td->orig_buffer = NULL;
84 return 1;
85 }
86 } else if (td->o.mem_type == MEM_MMAP ||
87 td->o.mem_type == MEM_MMAPHUGE) {
88 int flags = MAP_PRIVATE;
89
90 td->mmapfd = 0;
91
92 if (td->mmapfile) {
93 td->mmapfd = open(td->mmapfile, O_RDWR|O_CREAT, 0644);
94
95 if (td->mmapfd < 0) {
96 td_verror(td, errno, "open mmap file");
97 td->orig_buffer = NULL;
98 return 1;
99 }
100 if (ftruncate(td->mmapfd, td->orig_buffer_size) < 0) {
101 td_verror(td, errno, "truncate mmap file");
102 td->orig_buffer = NULL;
103 return 1;
104 }
105 } else
106 flags |= OS_MAP_ANON;
107
108 td->orig_buffer = mmap(NULL, td->orig_buffer_size, PROT_READ | PROT_WRITE, flags, td->mmapfd, 0);
109 if (td->orig_buffer == MAP_FAILED) {
110 td_verror(td, errno, "mmap");
111 td->orig_buffer = NULL;
112 if (td->mmapfd) {
113 close(td->mmapfd);
114 unlink(td->mmapfile);
115 }
116
117 return 1;
118 }
119 }
120
121 return 0;
122}
123
124void free_io_mem(struct thread_data *td)
125{
126 if (td->o.mem_type == MEM_MALLOC)
127 free(td->orig_buffer);
128 else if (td->o.mem_type == MEM_SHM || td->o.mem_type == MEM_SHMHUGE) {
129 struct shmid_ds sbuf;
130
131 shmdt(td->orig_buffer);
132 shmctl(td->shm_id, IPC_RMID, &sbuf);
133 } else if (td->o.mem_type == MEM_MMAP ||
134 td->o.mem_type == MEM_MMAPHUGE) {
135 munmap(td->orig_buffer, td->orig_buffer_size);
136 if (td->mmapfile) {
137 close(td->mmapfd);
138 unlink(td->mmapfile);
139 free(td->mmapfile);
140 }
141 } else
142 log_err("Bad memory type %u\n", td->o.mem_type);
143
144 td->orig_buffer = NULL;
145}