Mercurial > hg > nginx
annotate src/os/unix/ngx_linux_aio_read.c @ 5245:711fa02afae8
Valgrind: supressed complaints about uninitialized bytes.
Valgrind complains if we pass uninitialized memory to a syscall:
==36492== Syscall param sendmsg(msg.msg_iov[0]) points to uninitialised byte(s)
==36492== at 0x6B5E6A: sendmsg (in /usr/lib/system/libsystem_kernel.dylib)
==36492== by 0x10004288E: ngx_signal_worker_processes (ngx_process_cycle.c:527)
==36492== by 0x1000417A7: ngx_master_process_cycle (ngx_process_cycle.c:203)
==36492== by 0x100001F10: main (nginx.c:410)
==36492== Address 0x7fff5fbff71c is on thread 1's stack
Even initialization of all members of the structure passed isn't enough, as
there is padding which still remains uninitialized and results in Valgrind
complaint. Note there is no real problem here as data from uninitialized
memory isn't used.
| author | Maxim Dounin <mdounin@mdounin.ru> |
|---|---|
| date | Wed, 05 Jun 2013 19:44:22 +0400 |
| parents | d620f497c50f |
| children | ccad84a174e0 |
| rev | line source |
|---|---|
| 3052 | 1 |
| 2 /* | |
| 3 * Copyright (C) Igor Sysoev | |
| 4412 | 4 * Copyright (C) Nginx, Inc. |
| 3052 | 5 */ |
| 6 | |
| 7 | |
| 8 #include <ngx_config.h> | |
| 9 #include <ngx_core.h> | |
| 10 #include <ngx_event.h> | |
| 11 | |
| 12 | |
| 13 extern int ngx_eventfd; | |
| 14 extern aio_context_t ngx_aio_ctx; | |
| 15 | |
| 16 | |
| 17 static void ngx_file_aio_event_handler(ngx_event_t *ev); | |
| 18 | |
| 19 | |
|
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
|
20 static int |
| 3052 | 21 io_submit(aio_context_t ctx, long n, struct iocb **paiocb) |
| 22 { | |
| 23 return syscall(SYS_io_submit, ctx, n, paiocb); | |
| 24 } | |
| 25 | |
| 26 | |
| 27 ssize_t | |
| 28 ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset, | |
| 29 ngx_pool_t *pool) | |
| 30 { | |
|
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
|
31 ngx_err_t err; |
|
3294
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
diff
changeset
|
32 struct iocb *piocb[1]; |
|
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
diff
changeset
|
33 ngx_event_t *ev; |
|
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
diff
changeset
|
34 ngx_event_aio_t *aio; |
| 3052 | 35 |
|
3294
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
diff
changeset
|
36 if (!ngx_file_aio) { |
| 3052 | 37 return ngx_read_file(file, buf, size, offset); |
| 38 } | |
| 39 | |
| 40 aio = file->aio; | |
| 41 | |
| 42 if (aio == NULL) { | |
| 43 aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t)); | |
| 44 if (aio == NULL) { | |
| 45 return NGX_ERROR; | |
| 46 } | |
| 47 | |
| 48 aio->file = file; | |
| 49 aio->fd = file->fd; | |
| 50 aio->event.data = aio; | |
| 51 aio->event.ready = 1; | |
| 52 aio->event.log = file->log; | |
| 53 file->aio = aio; | |
| 54 } | |
| 55 | |
| 56 ev = &aio->event; | |
| 57 | |
| 58 if (!ev->ready) { | |
| 59 ngx_log_error(NGX_LOG_ALERT, file->log, 0, | |
| 60 "second aio post for \"%V\"", &file->name); | |
| 61 return NGX_AGAIN; | |
| 62 } | |
| 63 | |
| 64 ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0, | |
| 65 "aio complete:%d @%O:%z %V", | |
| 66 ev->complete, offset, size, &file->name); | |
| 67 | |
| 68 if (ev->complete) { | |
| 69 ev->active = 0; | |
| 70 ev->complete = 0; | |
| 71 | |
| 72 if (aio->res >= 0) { | |
| 73 ngx_set_errno(0); | |
| 74 return aio->res; | |
| 75 } | |
| 76 | |
| 77 ngx_set_errno(-aio->res); | |
|
4076
37da005a5808
Bugfix: open_file_cache lost is_directio flag.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3777
diff
changeset
|
78 |
|
37da005a5808
Bugfix: open_file_cache lost is_directio flag.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3777
diff
changeset
|
79 ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, |
|
37da005a5808
Bugfix: open_file_cache lost is_directio flag.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3777
diff
changeset
|
80 "aio read \"%s\" failed", file->name.data); |
|
37da005a5808
Bugfix: open_file_cache lost is_directio flag.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3777
diff
changeset
|
81 |
| 3052 | 82 return NGX_ERROR; |
| 83 } | |
| 84 | |
| 85 ngx_memzero(&aio->aiocb, sizeof(struct iocb)); | |
| 86 | |
| 87 aio->aiocb.aio_data = (uint64_t) (uintptr_t) ev; | |
| 88 aio->aiocb.aio_lio_opcode = IOCB_CMD_PREAD; | |
| 89 aio->aiocb.aio_fildes = file->fd; | |
| 90 aio->aiocb.aio_buf = (uint64_t) (uintptr_t) buf; | |
| 91 aio->aiocb.aio_nbytes = size; | |
| 92 aio->aiocb.aio_offset = offset; | |
| 93 aio->aiocb.aio_flags = IOCB_FLAG_RESFD; | |
| 94 aio->aiocb.aio_resfd = ngx_eventfd; | |
| 95 | |
| 96 ev->handler = ngx_file_aio_event_handler; | |
| 97 | |
| 98 piocb[0] = &aio->aiocb; | |
| 99 | |
|
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
|
100 if (io_submit(ngx_aio_ctx, 1, piocb) == 1) { |
|
3777
cd04f652478c
update event flags after successful io_submit()
Igor Sysoev <igor@sysoev.ru>
parents:
3294
diff
changeset
|
101 ev->active = 1; |
|
cd04f652478c
update event flags after successful io_submit()
Igor Sysoev <igor@sysoev.ru>
parents:
3294
diff
changeset
|
102 ev->ready = 0; |
|
cd04f652478c
update event flags after successful io_submit()
Igor Sysoev <igor@sysoev.ru>
parents:
3294
diff
changeset
|
103 ev->complete = 0; |
|
cd04f652478c
update event flags after successful io_submit()
Igor Sysoev <igor@sysoev.ru>
parents:
3294
diff
changeset
|
104 |
| 3052 | 105 return NGX_AGAIN; |
| 106 } | |
| 107 | |
|
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
|
108 err = ngx_errno; |
| 3052 | 109 |
|
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
|
110 if (err == NGX_EAGAIN) { |
| 3052 | 111 return ngx_read_file(file, buf, size, offset); |
| 112 } | |
| 113 | |
|
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
|
114 ngx_log_error(NGX_LOG_CRIT, file->log, err, |
| 3052 | 115 "io_submit(\"%V\") failed", &file->name); |
| 116 | |
|
4129
6903dac6ad19
Fixing Linux AIO syscalls return value handling:
Igor Sysoev <igor@sysoev.ru>
parents:
4076
diff
changeset
|
117 if (err == NGX_ENOSYS) { |
|
3294
04cfc09b8b8d
export aio presence knowledge to prevent using "aio sendfile",
Igor Sysoev <igor@sysoev.ru>
parents:
3052
diff
changeset
|
118 ngx_file_aio = 0; |
| 3052 | 119 return ngx_read_file(file, buf, size, offset); |
| 120 } | |
| 121 | |
| 122 return NGX_ERROR; | |
| 123 } | |
| 124 | |
| 125 | |
| 126 static void | |
| 127 ngx_file_aio_event_handler(ngx_event_t *ev) | |
| 128 { | |
| 129 ngx_event_aio_t *aio; | |
| 130 | |
| 131 aio = ev->data; | |
| 132 | |
| 133 ngx_log_debug2(NGX_LOG_DEBUG_CORE, ev->log, 0, | |
| 134 "aio event handler fd:%d %V", aio->fd, &aio->file->name); | |
| 135 | |
| 136 aio->handler(ev); | |
| 137 } |