2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; only version 2
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 #include <lttng/ust-ctl.h>
22 #include <lttng/ust-abi.h>
23 #include <lttng/ust-events.h>
26 #include <usterr-signal-safe.h>
29 #include "../libringbuffer/backend.h"
30 #include "../libringbuffer/frontend.h"
32 volatile enum ust_loglevel ust_loglevel
;
35 void init_object(struct lttng_ust_object_data
*data
)
40 data
->memory_map_size
= 0;
43 int ustctl_release_handle(int sock
, int handle
)
45 struct ustcomm_ust_msg lum
;
46 struct ustcomm_ust_reply lur
;
50 memset(&lum
, 0, sizeof(lum
));
52 lum
.cmd
= LTTNG_UST_RELEASE
;
53 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
61 * If sock is negative, it means we don't have to notify the other side
62 * (e.g. application has already vanished).
64 int ustctl_release_object(int sock
, struct lttng_ust_object_data
*data
)
68 if (data
->shm_fd
>= 0) {
69 ret
= close(data
->shm_fd
);
74 if (data
->wait_fd
>= 0) {
75 ret
= close(data
->wait_fd
);
80 return ustctl_release_handle(sock
, data
->handle
);
84 * Send registration done packet to the application.
86 int ustctl_register_done(int sock
)
88 struct ustcomm_ust_msg lum
;
89 struct ustcomm_ust_reply lur
;
92 DBG("Sending register done command to %d", sock
);
93 memset(&lum
, 0, sizeof(lum
));
94 lum
.handle
= LTTNG_UST_ROOT_HANDLE
;
95 lum
.cmd
= LTTNG_UST_REGISTER_DONE
;
96 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
99 if (lur
.ret_code
!= USTCOMM_OK
) {
100 DBG("Return code: %s", ustcomm_get_readable_code(lur
.ret_code
));
110 * returns session handle.
112 int ustctl_create_session(int sock
)
114 struct ustcomm_ust_msg lum
;
115 struct ustcomm_ust_reply lur
;
116 int ret
, session_handle
;
119 memset(&lum
, 0, sizeof(lum
));
120 lum
.handle
= LTTNG_UST_ROOT_HANDLE
;
121 lum
.cmd
= LTTNG_UST_SESSION
;
122 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
125 session_handle
= lur
.ret_val
;
126 DBG("received session handle %u", session_handle
);
127 return session_handle
;
130 /* open the metadata global channel */
131 int ustctl_open_metadata(int sock
, int session_handle
,
132 struct lttng_ust_channel_attr
*chops
,
133 struct lttng_ust_object_data
**_metadata_data
)
135 struct ustcomm_ust_msg lum
;
136 struct ustcomm_ust_reply lur
;
137 struct lttng_ust_object_data
*metadata_data
;
140 metadata_data
= malloc(sizeof(*metadata_data
));
143 init_object(metadata_data
);
144 /* Create metadata channel */
145 memset(&lum
, 0, sizeof(lum
));
146 lum
.handle
= session_handle
;
147 lum
.cmd
= LTTNG_UST_METADATA
;
148 lum
.u
.channel
.overwrite
= chops
->overwrite
;
149 lum
.u
.channel
.subbuf_size
= chops
->subbuf_size
;
150 lum
.u
.channel
.num_subbuf
= chops
->num_subbuf
;
151 lum
.u
.channel
.switch_timer_interval
= chops
->switch_timer_interval
;
152 lum
.u
.channel
.read_timer_interval
= chops
->read_timer_interval
;
153 lum
.u
.channel
.output
= chops
->output
;
154 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
159 if (lur
.ret_code
!= USTCOMM_OK
) {
163 metadata_data
->handle
= lur
.ret_val
;
164 DBG("received metadata handle %u", metadata_data
->handle
);
165 metadata_data
->memory_map_size
= lur
.u
.channel
.memory_map_size
;
167 ret
= ustcomm_recv_fd(sock
);
171 metadata_data
->shm_fd
= ret
;
173 * We need to get the second FD even if the first fails, because
174 * libust expects us to read the two FDs.
177 ret
= ustcomm_recv_fd(sock
);
181 metadata_data
->wait_fd
= ret
;
184 *_metadata_data
= metadata_data
;
188 (void) ustctl_release_object(sock
, metadata_data
);
193 int ustctl_create_channel(int sock
, int session_handle
,
194 struct lttng_ust_channel_attr
*chops
,
195 struct lttng_ust_object_data
**_channel_data
)
197 struct ustcomm_ust_msg lum
;
198 struct ustcomm_ust_reply lur
;
199 struct lttng_ust_object_data
*channel_data
;
202 channel_data
= malloc(sizeof(*channel_data
));
205 init_object(channel_data
);
206 /* Create metadata channel */
207 memset(&lum
, 0, sizeof(lum
));
208 lum
.handle
= session_handle
;
209 lum
.cmd
= LTTNG_UST_CHANNEL
;
210 lum
.u
.channel
.overwrite
= chops
->overwrite
;
211 lum
.u
.channel
.subbuf_size
= chops
->subbuf_size
;
212 lum
.u
.channel
.num_subbuf
= chops
->num_subbuf
;
213 lum
.u
.channel
.switch_timer_interval
= chops
->switch_timer_interval
;
214 lum
.u
.channel
.read_timer_interval
= chops
->read_timer_interval
;
215 lum
.u
.channel
.output
= chops
->output
;
216 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
221 if (lur
.ret_code
!= USTCOMM_OK
) {
225 channel_data
->handle
= lur
.ret_val
;
226 DBG("received channel handle %u", channel_data
->handle
);
227 channel_data
->memory_map_size
= lur
.u
.channel
.memory_map_size
;
229 ret
= ustcomm_recv_fd(sock
);
233 channel_data
->shm_fd
= ret
;
235 * We need to get the second FD even if the first fails, because
236 * libust expects us to read the two FDs.
239 ret
= ustcomm_recv_fd(sock
);
243 channel_data
->wait_fd
= ret
;
246 *_channel_data
= channel_data
;
250 (void) ustctl_release_object(sock
, channel_data
);
256 * Return -ENOENT if no more stream is available for creation.
257 * Return 0 on success.
258 * Return negative error value on error.
260 int ustctl_create_stream(int sock
, struct lttng_ust_object_data
*channel_data
,
261 struct lttng_ust_object_data
**_stream_data
)
263 struct ustcomm_ust_msg lum
;
264 struct ustcomm_ust_reply lur
;
265 struct lttng_ust_object_data
*stream_data
;
266 int ret
, fd
, err
= 0;
268 stream_data
= malloc(sizeof(*stream_data
));
271 init_object(stream_data
);
272 memset(&lum
, 0, sizeof(lum
));
273 lum
.handle
= channel_data
->handle
;
274 lum
.cmd
= LTTNG_UST_STREAM
;
275 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
280 if (lur
.ret_code
!= USTCOMM_OK
) {
285 stream_data
->handle
= lur
.ret_val
;
286 DBG("received stream handle %u", stream_data
->handle
);
287 stream_data
->memory_map_size
= lur
.u
.stream
.memory_map_size
;
289 fd
= ustcomm_recv_fd(sock
);
293 stream_data
->shm_fd
= fd
;
295 * We need to get the second FD even if the first fails, because
296 * libust expects us to read the two FDs.
299 fd
= ustcomm_recv_fd(sock
);
303 stream_data
->wait_fd
= fd
;
306 *_stream_data
= stream_data
;
310 (void) ustctl_release_object(sock
, stream_data
);
315 int ustctl_create_event(int sock
, struct lttng_ust_event
*ev
,
316 struct lttng_ust_object_data
*channel_data
,
317 struct lttng_ust_object_data
**_event_data
)
319 struct ustcomm_ust_msg lum
;
320 struct ustcomm_ust_reply lur
;
321 struct lttng_ust_object_data
*event_data
;
324 event_data
= malloc(sizeof(*event_data
));
327 init_object(event_data
);
328 memset(&lum
, 0, sizeof(lum
));
329 lum
.handle
= channel_data
->handle
;
330 lum
.cmd
= LTTNG_UST_EVENT
;
331 strncpy(lum
.u
.event
.name
, ev
->name
,
332 LTTNG_UST_SYM_NAME_LEN
);
333 lum
.u
.event
.instrumentation
= ev
->instrumentation
;
334 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
339 event_data
->handle
= lur
.ret_val
;
340 DBG("received event handle %u", event_data
->handle
);
341 *_event_data
= event_data
;
345 int ustctl_add_context(int sock
, struct lttng_ust_context
*ctx
,
346 struct lttng_ust_object_data
*obj_data
,
347 struct lttng_ust_object_data
**_context_data
)
349 struct ustcomm_ust_msg lum
;
350 struct ustcomm_ust_reply lur
;
351 struct lttng_ust_object_data
*context_data
;
354 context_data
= malloc(sizeof(*context_data
));
357 init_object(context_data
);
358 memset(&lum
, 0, sizeof(lum
));
359 lum
.handle
= obj_data
->handle
;
360 lum
.cmd
= LTTNG_UST_CONTEXT
;
361 lum
.u
.context
.ctx
= ctx
->ctx
;
362 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
367 context_data
->handle
= lur
.ret_val
;
368 DBG("received context handle %u", context_data
->handle
);
369 *_context_data
= context_data
;
373 /* Enable event, channel and session ioctl */
374 int ustctl_enable(int sock
, struct lttng_ust_object_data
*object
)
376 struct ustcomm_ust_msg lum
;
377 struct ustcomm_ust_reply lur
;
380 memset(&lum
, 0, sizeof(lum
));
381 lum
.handle
= object
->handle
;
382 lum
.cmd
= LTTNG_UST_ENABLE
;
383 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
386 DBG("enabled handle %u", object
->handle
);
390 /* Disable event, channel and session ioctl */
391 int ustctl_disable(int sock
, struct lttng_ust_object_data
*object
)
393 struct ustcomm_ust_msg lum
;
394 struct ustcomm_ust_reply lur
;
397 memset(&lum
, 0, sizeof(lum
));
398 lum
.handle
= object
->handle
;
399 lum
.cmd
= LTTNG_UST_DISABLE
;
400 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
403 DBG("disable handle %u", object
->handle
);
407 int ustctl_start_session(int sock
, int handle
)
409 struct lttng_ust_object_data obj
;
412 return ustctl_enable(sock
, &obj
);
415 int ustctl_stop_session(int sock
, int handle
)
417 struct lttng_ust_object_data obj
;
420 return ustctl_disable(sock
, &obj
);
423 int ustctl_tracepoint_list(int sock
)
425 struct ustcomm_ust_msg lum
;
426 struct ustcomm_ust_reply lur
;
427 int ret
, tp_list_handle
;
429 memset(&lum
, 0, sizeof(lum
));
430 lum
.handle
= LTTNG_UST_ROOT_HANDLE
;
431 lum
.cmd
= LTTNG_UST_TRACEPOINT_LIST
;
432 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
435 tp_list_handle
= lur
.ret_val
;
436 DBG("received tracepoint list handle %u", tp_list_handle
);
437 return tp_list_handle
;
440 int ustctl_tracepoint_list_get(int sock
, int tp_list_handle
,
441 struct lttng_ust_tracepoint_iter
*iter
)
443 struct ustcomm_ust_msg lum
;
444 struct ustcomm_ust_reply lur
;
447 memset(&lum
, 0, sizeof(lum
));
448 lum
.handle
= tp_list_handle
;
449 lum
.cmd
= LTTNG_UST_TRACEPOINT_LIST_GET
;
450 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
453 DBG("received tracepoint list entry name %s loglevel %s loglevel_value %lld",
454 lur
.u
.tracepoint
.name
,
455 lur
.u
.tracepoint
.loglevel
,
456 (unsigned long long) lur
.u
.tracepoint
.loglevel_value
);
457 memcpy(iter
, &lur
.u
.tracepoint
, sizeof(*iter
));
461 int ustctl_tracer_version(int sock
, struct lttng_ust_tracer_version
*v
)
463 struct ustcomm_ust_msg lum
;
464 struct ustcomm_ust_reply lur
;
467 memset(&lum
, 0, sizeof(lum
));
468 lum
.handle
= LTTNG_UST_ROOT_HANDLE
;
469 lum
.cmd
= LTTNG_UST_TRACER_VERSION
;
470 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
473 memcpy(v
, &lur
.u
.version
, sizeof(*v
));
474 DBG("received tracer version");
478 int ustctl_wait_quiescent(int sock
)
480 struct ustcomm_ust_msg lum
;
481 struct ustcomm_ust_reply lur
;
484 memset(&lum
, 0, sizeof(lum
));
485 lum
.handle
= LTTNG_UST_ROOT_HANDLE
;
486 lum
.cmd
= LTTNG_UST_WAIT_QUIESCENT
;
487 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
490 DBG("waited for quiescent state");
494 int ustctl_calibrate(int sock
, struct lttng_ust_calibrate
*calibrate
)
499 int ustctl_sock_flush_buffer(int sock
, struct lttng_ust_object_data
*object
)
501 struct ustcomm_ust_msg lum
;
502 struct ustcomm_ust_reply lur
;
505 memset(&lum
, 0, sizeof(lum
));
506 lum
.handle
= object
->handle
;
507 lum
.cmd
= LTTNG_UST_FLUSH_BUFFER
;
508 ret
= ustcomm_send_app_cmd(sock
, &lum
, &lur
);
511 DBG("flushed buffer handle %u", object
->handle
);
515 /* Buffer operations */
517 /* Map channel shm into process memory */
518 struct lttng_ust_shm_handle
*ustctl_map_channel(struct lttng_ust_object_data
*chan_data
)
520 struct lttng_ust_shm_handle
*handle
;
521 struct channel
*chan
;
523 struct lttng_ust_lib_ring_buffer_config
*config
;
526 handle
= channel_handle_create(chan_data
->shm_fd
,
528 chan_data
->memory_map_size
);
530 ERR("create handle error");
534 * Set to -1, and then close the shm fd, and set the handle shm
535 * fd to -1 too. We don't need the shm fds after they have been
537 * The wait_fd is set to -1 in chan_data because it is now owned
540 chan_data
->shm_fd
= -1;
541 chan_data
->wait_fd
= -1;
543 /* chan is object 0. This is hardcoded. */
544 if (handle
->table
->objects
[0].shm_fd
>= 0) {
545 ret
= close(handle
->table
->objects
[0].shm_fd
);
547 perror("Error closing shm_fd");
549 handle
->table
->objects
[0].shm_fd
= -1;
553 * TODO: add consistency checks to be resilient if the
554 * application try to feed us with incoherent channel structure
557 chan
= shmp(handle
, handle
->chan
);
558 /* chan is object 0. This is hardcoded. */
559 chan_size
= handle
->table
->objects
[0].allocated_len
;
560 handle
->shadow_chan
= malloc(chan_size
);
561 if (!handle
->shadow_chan
) {
562 channel_destroy(chan
, handle
, 1);
565 memcpy(handle
->shadow_chan
, chan
, chan_size
);
567 * The callback pointers in the producer are invalid in the
568 * consumer. We need to look them up here.
570 config
= &handle
->shadow_chan
->backend
.config
;
571 switch (config
->client_type
) {
572 case LTTNG_CLIENT_METADATA
:
573 memcpy(&config
->cb
, lttng_client_callbacks_metadata
,
576 case LTTNG_CLIENT_DISCARD
:
577 memcpy(&config
->cb
, lttng_client_callbacks_discard
,
580 case LTTNG_CLIENT_OVERWRITE
:
581 memcpy(&config
->cb
, lttng_client_callbacks_overwrite
,
585 ERR("Unknown client type %d", config
->client_type
);
586 channel_destroy(chan
, handle
, 1);
589 /* Replace the object table pointer. */
590 ret
= munmap(handle
->table
->objects
[0].memory_map
,
591 handle
->table
->objects
[0].memory_map_size
);
596 handle
->table
->objects
[0].memory_map
= (char *) handle
->shadow_chan
;
597 handle
->table
->objects
[0].is_shadow
= 1;
601 /* Add stream to channel shm and map its shm into process memory */
602 int ustctl_add_stream(struct lttng_ust_shm_handle
*handle
,
603 struct lttng_ust_object_data
*stream_data
)
607 if (!stream_data
->handle
)
610 ret
= channel_handle_add_stream(handle
,
612 stream_data
->wait_fd
,
613 stream_data
->memory_map_size
);
615 ERR("add stream error\n");
619 * Set to -1 because the lttng_ust_shm_handle destruction will take care
620 * of closing shm_fd and wait_fd.
622 stream_data
->shm_fd
= -1;
623 stream_data
->wait_fd
= -1;
627 void ustctl_unmap_channel(struct lttng_ust_shm_handle
*handle
)
629 struct channel
*chan
;
631 chan
= shmp(handle
, handle
->chan
);
632 channel_destroy(chan
, handle
, 1);
636 * ustctl closes the shm_fd fds after mapping it.
638 struct lttng_ust_lib_ring_buffer
*ustctl_open_stream_read(struct lttng_ust_shm_handle
*handle
,
641 struct channel
*chan
= handle
->shadow_chan
;
642 int *shm_fd
, *wait_fd
;
643 uint64_t *memory_map_size
;
644 struct lttng_ust_lib_ring_buffer
*buf
;
647 buf
= channel_get_ring_buffer(&chan
->backend
.config
,
648 chan
, cpu
, handle
, &shm_fd
, &wait_fd
, &memory_map_size
);
651 ret
= lib_ring_buffer_open_read(buf
, handle
, 1);
655 * We can close shm_fd early, right after is has been mapped.
658 ret
= close(*shm_fd
);
660 perror("Error closing shm_fd");
667 void ustctl_close_stream_read(struct lttng_ust_shm_handle
*handle
,
668 struct lttng_ust_lib_ring_buffer
*buf
)
670 lib_ring_buffer_release_read(buf
, handle
, 1);
673 /* For mmap mode, readable without "get" operation */
675 void *ustctl_get_mmap_base(struct lttng_ust_shm_handle
*handle
,
676 struct lttng_ust_lib_ring_buffer
*buf
)
678 return shmp(handle
, buf
->backend
.memory_map
);
681 /* returns the length to mmap. */
682 int ustctl_get_mmap_len(struct lttng_ust_shm_handle
*handle
,
683 struct lttng_ust_lib_ring_buffer
*buf
,
686 unsigned long mmap_buf_len
;
687 struct channel
*chan
= handle
->shadow_chan
;
689 if (chan
->backend
.config
.output
!= RING_BUFFER_MMAP
)
691 mmap_buf_len
= chan
->backend
.buf_size
;
692 if (chan
->backend
.extra_reader_sb
)
693 mmap_buf_len
+= chan
->backend
.subbuf_size
;
694 if (mmap_buf_len
> INT_MAX
)
700 /* returns the maximum size for sub-buffers. */
701 int ustctl_get_max_subbuf_size(struct lttng_ust_shm_handle
*handle
,
702 struct lttng_ust_lib_ring_buffer
*buf
,
705 struct channel
*chan
= handle
->shadow_chan
;
707 *len
= chan
->backend
.subbuf_size
;
712 * For mmap mode, operate on the current packet (between get/put or
713 * get_next/put_next).
716 /* returns the offset of the subbuffer belonging to the mmap reader. */
717 int ustctl_get_mmap_read_offset(struct lttng_ust_shm_handle
*handle
,
718 struct lttng_ust_lib_ring_buffer
*buf
, unsigned long *off
)
720 struct channel
*chan
= handle
->shadow_chan
;
721 unsigned long sb_bindex
;
723 if (chan
->backend
.config
.output
!= RING_BUFFER_MMAP
)
725 sb_bindex
= subbuffer_id_get_index(&chan
->backend
.config
,
726 buf
->backend
.buf_rsb
.id
);
727 *off
= shmp(handle
, shmp_index(handle
, buf
->backend
.array
, sb_bindex
)->shmp
)->mmap_offset
;
731 /* returns the size of the current sub-buffer, without padding (for mmap). */
732 int ustctl_get_subbuf_size(struct lttng_ust_shm_handle
*handle
,
733 struct lttng_ust_lib_ring_buffer
*buf
, unsigned long *len
)
735 struct channel
*chan
= handle
->shadow_chan
;
737 *len
= lib_ring_buffer_get_read_data_size(&chan
->backend
.config
, buf
,
742 /* returns the size of the current sub-buffer, without padding (for mmap). */
743 int ustctl_get_padded_subbuf_size(struct lttng_ust_shm_handle
*handle
,
744 struct lttng_ust_lib_ring_buffer
*buf
, unsigned long *len
)
746 struct channel
*chan
= handle
->shadow_chan
;
748 *len
= lib_ring_buffer_get_read_data_size(&chan
->backend
.config
, buf
,
750 *len
= PAGE_ALIGN(*len
);
754 /* Get exclusive read access to the next sub-buffer that can be read. */
755 int ustctl_get_next_subbuf(struct lttng_ust_shm_handle
*handle
,
756 struct lttng_ust_lib_ring_buffer
*buf
)
758 return lib_ring_buffer_get_next_subbuf(buf
, handle
);
762 /* Release exclusive sub-buffer access, move consumer forward. */
763 int ustctl_put_next_subbuf(struct lttng_ust_shm_handle
*handle
,
764 struct lttng_ust_lib_ring_buffer
*buf
)
766 lib_ring_buffer_put_next_subbuf(buf
, handle
);
772 /* Get a snapshot of the current ring buffer producer and consumer positions */
773 int ustctl_snapshot(struct lttng_ust_shm_handle
*handle
,
774 struct lttng_ust_lib_ring_buffer
*buf
)
776 return lib_ring_buffer_snapshot(buf
, &buf
->cons_snapshot
,
777 &buf
->prod_snapshot
, handle
);
780 /* Get the consumer position (iteration start) */
781 int ustctl_snapshot_get_consumed(struct lttng_ust_shm_handle
*handle
,
782 struct lttng_ust_lib_ring_buffer
*buf
, unsigned long *pos
)
784 *pos
= buf
->cons_snapshot
;
788 /* Get the producer position (iteration end) */
789 int ustctl_snapshot_get_produced(struct lttng_ust_shm_handle
*handle
,
790 struct lttng_ust_lib_ring_buffer
*buf
, unsigned long *pos
)
792 *pos
= buf
->prod_snapshot
;
796 /* Get exclusive read access to the specified sub-buffer position */
797 int ustctl_get_subbuf(struct lttng_ust_shm_handle
*handle
,
798 struct lttng_ust_lib_ring_buffer
*buf
, unsigned long *pos
)
800 return lib_ring_buffer_get_subbuf(buf
, *pos
, handle
);
803 /* Release exclusive sub-buffer access */
804 int ustctl_put_subbuf(struct lttng_ust_shm_handle
*handle
,
805 struct lttng_ust_lib_ring_buffer
*buf
)
807 lib_ring_buffer_put_subbuf(buf
, handle
);
811 void ustctl_flush_buffer(struct lttng_ust_shm_handle
*handle
,
812 struct lttng_ust_lib_ring_buffer
*buf
,
815 lib_ring_buffer_switch_slow(buf
,
816 producer_active
? SWITCH_ACTIVE
: SWITCH_FLUSH
,