memory.c revision 83ea422a62b8a42b14c362db61c2e7bf53862e80 
1/*
2 * Memory helpers
3 */
4#include <sys/types.h>
5#include <sys/stat.h>
6#include <fcntl.h>
7#include <unistd.h>
8#include <sys/shm.h>
9#include <sys/mman.h>
10
11#include "fio.h"
12
13static void *pinned_mem;
14
15void fio_unpin_memory(void)
16{
17	if (pinned_mem) {
18		dprint(FD_MEM, "unpinning %llu bytes\n", mlock_size);
19		if (munlock(pinned_mem, mlock_size) < 0)
20			perror("munlock");
21		munmap(pinned_mem, mlock_size);
22		pinned_mem = NULL;
23	}
24}
25
26int fio_pin_memory(void)
27{
28	unsigned long long phys_mem;
29
30	if (!mlock_size)
31		return 0;
32
33	dprint(FD_MEM, "pinning %llu bytes\n", mlock_size);
34
35	/*
36	 * Don't allow mlock of more than real_mem-128MB
37	 */
38	phys_mem = os_phys_mem();
39	if (phys_mem) {
40		if ((mlock_size + 128 * 1024 * 1024) > phys_mem) {
41			mlock_size = phys_mem - 128 * 1024 * 1024;
42			log_info("fio: limiting mlocked memory to %lluMB\n",
43							mlock_size >> 20);
44		}
45	}
46
47	pinned_mem = mmap(NULL, mlock_size, PROT_READ | PROT_WRITE,
48				MAP_PRIVATE | OS_MAP_ANON, -1, 0);
49	if (pinned_mem == MAP_FAILED) {
50		perror("malloc locked mem");
51		pinned_mem = NULL;
52		return 1;
53	}
54	if (mlock(pinned_mem, mlock_size) < 0) {
55		perror("mlock");
56		munmap(pinned_mem, mlock_size);
57		pinned_mem = NULL;
58		return 1;
59	}
60
61	return 0;
62}
63
64static int alloc_mem_shm(struct thread_data *td, unsigned int total_mem)
65{
66	int flags = IPC_CREAT | S_IRUSR | S_IWUSR;
67
68	if (td->o.mem_type == MEM_SHMHUGE) {
69		unsigned long mask = td->o.hugepage_size - 1;
70
71		flags |= SHM_HUGETLB;
72		total_mem = (total_mem + mask) & ~mask;
73	}
74
75	td->shm_id = shmget(IPC_PRIVATE, total_mem, flags);
76	dprint(FD_MEM, "shmget %u, %d\n", total_mem, td->shm_id);
77	if (td->shm_id < 0) {
78		td_verror(td, errno, "shmget");
79		if (geteuid() != 0 && (errno == ENOMEM || errno == EPERM))
80			log_err("fio: you may need to run this job as root\n");
81		if (td->o.mem_type == MEM_SHMHUGE) {
82			if (errno == EINVAL) {
83				log_err("fio: check that you have free huge"
84					" pages and that hugepage-size is"
85					" correct.\n");
86			} else if (errno == ENOSYS) {
87				log_err("fio: your system does not appear to"
88					" support huge pages.\n");
89			} else if (errno == ENOMEM) {
90				log_err("fio: no huge pages available, do you"
91					" need to alocate some? See HOWTO.\n");
92			}
93		}
94
95		return 1;
96	}
97
98	td->orig_buffer = shmat(td->shm_id, NULL, 0);
99	dprint(FD_MEM, "shmat %d, %p\n", td->shm_id, td->orig_buffer);
100	if (td->orig_buffer == (void *) -1) {
101		td_verror(td, errno, "shmat");
102		td->orig_buffer = NULL;
103		return 1;
104	}
105
106	return 0;
107}
108
109static void free_mem_shm(struct thread_data *td)
110{
111	struct shmid_ds sbuf;
112
113	dprint(FD_MEM, "shmdt/ctl %d %p\n", td->shm_id, td->orig_buffer);
114	shmdt(td->orig_buffer);
115	shmctl(td->shm_id, IPC_RMID, &sbuf);
116}
117
118static int alloc_mem_mmap(struct thread_data *td, size_t total_mem)
119{
120	int flags = MAP_PRIVATE;
121
122	td->mmapfd = 1;
123
124	if (td->o.mmapfile) {
125		td->mmapfd = open(td->o.mmapfile, O_RDWR|O_CREAT, 0644);
126
127		if (td->mmapfd < 0) {
128			td_verror(td, errno, "open mmap file");
129			td->orig_buffer = NULL;
130			return 1;
131		}
132		if (ftruncate(td->mmapfd, total_mem) < 0) {
133			td_verror(td, errno, "truncate mmap file");
134			td->orig_buffer = NULL;
135			return 1;
136		}
137	} else
138		flags |= OS_MAP_ANON;
139
140	td->orig_buffer = mmap(NULL, total_mem, PROT_READ | PROT_WRITE, flags,
141				td->mmapfd, 0);
142	dprint(FD_MEM, "mmap %u/%d %p\n", total_mem, td->mmapfd,
143						td->orig_buffer);
144	if (td->orig_buffer == MAP_FAILED) {
145		td_verror(td, errno, "mmap");
146		td->orig_buffer = NULL;
147		if (td->mmapfd) {
148			close(td->mmapfd);
149			unlink(td->o.mmapfile);
150		}
151
152		return 1;
153	}
154
155	return 0;
156}
157
158static void free_mem_mmap(struct thread_data *td, size_t total_mem)
159{
160	dprint(FD_MEM, "munmap %u %p\n", total_mem, td->orig_buffer);
161	munmap(td->orig_buffer, td->orig_buffer_size);
162	if (td->o.mmapfile) {
163		close(td->mmapfd);
164		unlink(td->o.mmapfile);
165		free(td->o.mmapfile);
166	}
167}
168
169static int alloc_mem_malloc(struct thread_data *td, size_t total_mem)
170{
171	td->orig_buffer = malloc(total_mem);
172	dprint(FD_MEM, "malloc %u %p\n", total_mem, td->orig_buffer);
173
174	return td->orig_buffer == NULL;
175}
176
177static void free_mem_malloc(struct thread_data *td)
178{
179	dprint(FD_MEM, "free malloc mem %p\n", td->orig_buffer);
180	free(td->orig_buffer);
181}
182
183/*
184 * Set up the buffer area we need for io.
185 */
186int allocate_io_mem(struct thread_data *td)
187{
188	size_t total_mem;
189	int ret = 0;
190
191	if (td->io_ops->flags & FIO_NOIO)
192		return 0;
193
194	total_mem = td->orig_buffer_size;
195
196	if (td->o.odirect || td->o.mem_align ||
197	    (td->io_ops->flags & FIO_MEMALIGN)) {
198		total_mem += page_mask;
199		if (td->o.mem_align && td->o.mem_align > page_size)
200			total_mem += td->o.mem_align - page_size;
201	}
202
203	dprint(FD_MEM, "Alloc %lu for buffers\n", (size_t) total_mem);
204
205	if (td->o.mem_type == MEM_MALLOC)
206		ret = alloc_mem_malloc(td, total_mem);
207	else if (td->o.mem_type == MEM_SHM || td->o.mem_type == MEM_SHMHUGE)
208		ret = alloc_mem_shm(td, total_mem);
209	else if (td->o.mem_type == MEM_MMAP || td->o.mem_type == MEM_MMAPHUGE)
210		ret = alloc_mem_mmap(td, total_mem);
211	else {
212		log_err("fio: bad mem type: %d\n", td->o.mem_type);
213		ret = 1;
214	}
215
216	if (ret)
217		td_verror(td, ENOMEM, "iomem allocation");
218
219	return ret;
220}
221
222void free_io_mem(struct thread_data *td)
223{
224	unsigned int total_mem;
225
226	total_mem = td->orig_buffer_size;
227	if (td->o.odirect)
228		total_mem += page_mask;
229
230	if (td->o.mem_type == MEM_MALLOC)
231		free_mem_malloc(td);
232	else if (td->o.mem_type == MEM_SHM || td->o.mem_type == MEM_SHMHUGE)
233		free_mem_shm(td);
234	else if (td->o.mem_type == MEM_MMAP || td->o.mem_type == MEM_MMAPHUGE)
235		free_mem_mmap(td, total_mem);
236	else
237		log_err("Bad memory type %u\n", td->o.mem_type);
238
239	td->orig_buffer = NULL;
240	td->orig_buffer_size = 0;
241}
242