2 * Copyright (C) 2008-2011 Mathieu Desnoyers
3 * Copyright (C) 2009 Pierre-Marc Fournier
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation;
8 * version 2.1 of the License.
10 * This library 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 GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 * Ported to userspace by Pierre-Marc Fournier.
28 #include <urcu/arch.h>
30 #include <urcu/hlist.h>
31 #include <urcu/uatomic.h>
32 #include <urcu/compiler.h>
33 #include <urcu/system.h>
35 #include <lttng/tracepoint.h>
36 #include <lttng/ust-abi.h> /* for LTTNG_UST_SYM_NAME_LEN */
38 #include <usterr-signal-safe.h>
41 #include "tracepoint-internal.h"
42 #include "lttng-tracer-core.h"
46 /* Set to 1 to enable tracepoint debug output */
47 static const int tracepoint_debug
;
48 static int initialized
;
49 static void (*new_tracepoint_cb
)(struct lttng_ust_tracepoint
*);
52 * tracepoint_mutex nests inside UST mutex.
54 * Note about interaction with fork/clone: UST does not hold the
55 * tracepoint mutex across fork/clone because it is either:
56 * - nested within UST mutex, in which case holding the UST mutex across
58 * - taken by a library constructor, which should never race with a
59 * fork/clone if the application is expected to continue running with
60 * the same memory layout (no following exec()).
62 static pthread_mutex_t tracepoint_mutex
= PTHREAD_MUTEX_INITIALIZER
;
65 * libraries that contain tracepoints (struct tracepoint_lib).
66 * Protected by tracepoint mutex.
68 static CDS_LIST_HEAD(libs
);
71 * The tracepoint mutex protects the library tracepoints, the hash table, and
73 * All calls to the tracepoint API must be protected by the tracepoint mutex,
74 * excepts calls to tracepoint_register_lib and
75 * tracepoint_unregister_lib, which take the tracepoint mutex themselves.
79 * Tracepoint hash table, containing the active tracepoints.
80 * Protected by tracepoint mutex.
82 #define TRACEPOINT_HASH_BITS 12
83 #define TRACEPOINT_TABLE_SIZE (1 << TRACEPOINT_HASH_BITS)
84 static struct cds_hlist_head tracepoint_table
[TRACEPOINT_TABLE_SIZE
];
86 static CDS_LIST_HEAD(old_probes
);
87 static int need_update
;
91 * It is used to to delay the free of multiple probes array until a quiescent
93 * Tracepoint entries modifications are protected by the tracepoint mutex.
95 struct tracepoint_entry
{
96 struct cds_hlist_node hlist
;
97 struct lttng_ust_tracepoint_probe
*probes
;
98 int refcount
; /* Number of times armed. 0 if disarmed. */
99 int callsite_refcount
; /* how many libs use this tracepoint */
100 const char *signature
;
106 struct cds_list_head list
;
107 /* Field below only used for call_rcu scheme */
108 /* struct rcu_head head; */
110 struct lttng_ust_tracepoint_probe probes
[0];
114 * Callsite hash table, containing the tracepoint call sites.
115 * Protected by tracepoint mutex.
117 #define CALLSITE_HASH_BITS 12
118 #define CALLSITE_TABLE_SIZE (1 << CALLSITE_HASH_BITS)
119 static struct cds_hlist_head callsite_table
[CALLSITE_TABLE_SIZE
];
121 struct callsite_entry
{
122 struct cds_hlist_node hlist
; /* hash table node */
123 struct cds_list_head node
; /* lib list of callsites node */
124 struct lttng_ust_tracepoint
*tp
;
127 /* coverity[+alloc] */
128 static void *allocate_probes(int count
)
130 struct tp_probes
*p
=
131 zmalloc(count
* sizeof(struct lttng_ust_tracepoint_probe
)
132 + sizeof(struct tp_probes
));
133 return p
== NULL
? NULL
: p
->probes
;
136 /* coverity[+free : arg-0] */
137 static void release_probes(void *old
)
140 struct tp_probes
*tp_probes
= caa_container_of(old
,
141 struct tp_probes
, probes
[0]);
147 static void debug_print_probes(struct tracepoint_entry
*entry
)
151 if (!tracepoint_debug
|| !entry
->probes
)
154 for (i
= 0; entry
->probes
[i
].func
; i
++)
155 DBG("Probe %d : %p", i
, entry
->probes
[i
].func
);
159 tracepoint_entry_add_probe(struct tracepoint_entry
*entry
,
160 void (*probe
)(void), void *data
)
163 struct lttng_ust_tracepoint_probe
*old
, *new;
167 return ERR_PTR(-EINVAL
);
169 debug_print_probes(entry
);
172 /* (N -> N+1), (N != 0, 1) probes */
173 for (nr_probes
= 0; old
[nr_probes
].func
; nr_probes
++)
174 if (old
[nr_probes
].func
== probe
&&
175 old
[nr_probes
].data
== data
)
176 return ERR_PTR(-EEXIST
);
178 /* + 2 : one for new probe, one for NULL func */
179 new = allocate_probes(nr_probes
+ 2);
181 return ERR_PTR(-ENOMEM
);
184 nr_probes
* sizeof(struct lttng_ust_tracepoint_probe
));
185 new[nr_probes
].func
= probe
;
186 new[nr_probes
].data
= data
;
187 new[nr_probes
+ 1].func
= NULL
;
188 entry
->refcount
= nr_probes
+ 1;
190 debug_print_probes(entry
);
195 tracepoint_entry_remove_probe(struct tracepoint_entry
*entry
,
196 void (*probe
)(void), void *data
)
198 int nr_probes
= 0, nr_del
= 0, i
;
199 struct lttng_ust_tracepoint_probe
*old
, *new;
204 return ERR_PTR(-ENOENT
);
206 debug_print_probes(entry
);
207 /* (N -> M), (N > 1, M >= 0) probes */
209 for (nr_probes
= 0; old
[nr_probes
].func
; nr_probes
++) {
210 if (old
[nr_probes
].func
== probe
&&
211 old
[nr_probes
].data
== data
)
216 if (nr_probes
- nr_del
== 0) {
217 /* N -> 0, (N > 1) */
218 entry
->probes
= NULL
;
220 debug_print_probes(entry
);
224 /* N -> M, (N > 1, M > 0) */
226 new = allocate_probes(nr_probes
- nr_del
+ 1);
228 return ERR_PTR(-ENOMEM
);
229 for (i
= 0; old
[i
].func
; i
++)
230 if (old
[i
].func
!= probe
|| old
[i
].data
!= data
)
232 new[nr_probes
- nr_del
].func
= NULL
;
233 entry
->refcount
= nr_probes
- nr_del
;
236 debug_print_probes(entry
);
241 * Get tracepoint if the tracepoint is present in the tracepoint hash table.
242 * Must be called with tracepoint mutex held.
243 * Returns NULL if not present.
245 static struct tracepoint_entry
*get_tracepoint(const char *name
)
247 struct cds_hlist_head
*head
;
248 struct cds_hlist_node
*node
;
249 struct tracepoint_entry
*e
;
250 size_t name_len
= strlen(name
);
253 if (name_len
> LTTNG_UST_SYM_NAME_LEN
- 1) {
254 WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name
, LTTNG_UST_SYM_NAME_LEN
- 1);
255 name_len
= LTTNG_UST_SYM_NAME_LEN
- 1;
257 hash
= jhash(name
, name_len
, 0);
258 head
= &tracepoint_table
[hash
& (TRACEPOINT_TABLE_SIZE
- 1)];
259 cds_hlist_for_each_entry(e
, node
, head
, hlist
) {
260 if (!strncmp(name
, e
->name
, LTTNG_UST_SYM_NAME_LEN
- 1))
267 * Add the tracepoint to the tracepoint hash table. Must be called with
268 * tracepoint mutex held.
270 static struct tracepoint_entry
*add_tracepoint(const char *name
,
271 const char *signature
)
273 struct cds_hlist_head
*head
;
274 struct cds_hlist_node
*node
;
275 struct tracepoint_entry
*e
;
276 size_t name_len
= strlen(name
);
279 if (name_len
> LTTNG_UST_SYM_NAME_LEN
- 1) {
280 WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name
, LTTNG_UST_SYM_NAME_LEN
- 1);
281 name_len
= LTTNG_UST_SYM_NAME_LEN
- 1;
283 hash
= jhash(name
, name_len
, 0);
284 head
= &tracepoint_table
[hash
& (TRACEPOINT_TABLE_SIZE
- 1)];
285 cds_hlist_for_each_entry(e
, node
, head
, hlist
) {
286 if (!strncmp(name
, e
->name
, LTTNG_UST_SYM_NAME_LEN
- 1)) {
287 DBG("tracepoint %s busy", name
);
288 return ERR_PTR(-EEXIST
); /* Already there */
292 * Using zmalloc here to allocate a variable length element. Could
293 * cause some memory fragmentation if overused.
295 e
= zmalloc(sizeof(struct tracepoint_entry
) + name_len
+ 1);
297 return ERR_PTR(-ENOMEM
);
298 memcpy(&e
->name
[0], name
, name_len
+ 1);
299 e
->name
[name_len
] = '\0';
302 e
->callsite_refcount
= 0;
303 e
->signature
= signature
;
304 cds_hlist_add_head(&e
->hlist
, head
);
309 * Remove the tracepoint from the tracepoint hash table. Must be called with
310 * tracepoint mutex held.
312 static void remove_tracepoint(struct tracepoint_entry
*e
)
314 cds_hlist_del(&e
->hlist
);
319 * Sets the probe callback corresponding to one tracepoint.
321 static void set_tracepoint(struct tracepoint_entry
**entry
,
322 struct lttng_ust_tracepoint
*elem
, int active
)
324 WARN_ON(strncmp((*entry
)->name
, elem
->name
, LTTNG_UST_SYM_NAME_LEN
- 1) != 0);
326 * Check that signatures match before connecting a probe to a
327 * tracepoint. Warn the user if they don't.
329 if (strcmp(elem
->signature
, (*entry
)->signature
) != 0) {
330 static int warned
= 0;
332 /* Only print once, don't flood console. */
334 WARN("Tracepoint signature mismatch, not enabling one or more tracepoints. Ensure that the tracepoint probes prototypes match the application.");
335 WARN("Tracepoint \"%s\" signatures: call: \"%s\" vs probe: \"%s\".",
336 elem
->name
, elem
->signature
, (*entry
)->signature
);
339 /* Don't accept connecting non-matching signatures. */
344 * rcu_assign_pointer has a cmm_smp_wmb() which makes sure that the new
345 * probe callbacks array is consistent before setting a pointer to it.
346 * This array is referenced by __DO_TRACE from
347 * include/linux/tracepoints.h. A matching cmm_smp_read_barrier_depends()
350 rcu_assign_pointer(elem
->probes
, (*entry
)->probes
);
351 CMM_STORE_SHARED(elem
->state
, active
);
355 * Disable a tracepoint and its probe callback.
356 * Note: only waiting an RCU period after setting elem->call to the empty
357 * function insures that the original callback is not used anymore. This insured
358 * by preempt_disable around the call site.
360 static void disable_tracepoint(struct lttng_ust_tracepoint
*elem
)
362 CMM_STORE_SHARED(elem
->state
, 0);
363 rcu_assign_pointer(elem
->probes
, NULL
);
367 * Add the callsite to the callsite hash table. Must be called with
368 * tracepoint mutex held.
370 static void add_callsite(struct tracepoint_lib
* lib
, struct lttng_ust_tracepoint
*tp
)
372 struct cds_hlist_head
*head
;
373 struct callsite_entry
*e
;
374 const char *name
= tp
->name
;
375 size_t name_len
= strlen(name
);
377 struct tracepoint_entry
*tp_entry
;
379 if (name_len
> LTTNG_UST_SYM_NAME_LEN
- 1) {
380 WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name
, LTTNG_UST_SYM_NAME_LEN
- 1);
381 name_len
= LTTNG_UST_SYM_NAME_LEN
- 1;
383 hash
= jhash(name
, name_len
, 0);
384 head
= &callsite_table
[hash
& (CALLSITE_TABLE_SIZE
- 1)];
385 e
= zmalloc(sizeof(struct callsite_entry
));
387 PERROR("Unable to add callsite for tracepoint \"%s\"", name
);
390 cds_hlist_add_head(&e
->hlist
, head
);
392 cds_list_add(&e
->node
, &lib
->callsites
);
394 tp_entry
= get_tracepoint(name
);
397 tp_entry
->callsite_refcount
++;
401 * Remove the callsite from the callsite hash table and from lib
402 * callsite list. Must be called with tracepoint mutex held.
404 static void remove_callsite(struct callsite_entry
*e
)
406 struct tracepoint_entry
*tp_entry
;
408 tp_entry
= get_tracepoint(e
->tp
->name
);
410 tp_entry
->callsite_refcount
--;
411 if (tp_entry
->callsite_refcount
== 0)
412 disable_tracepoint(e
->tp
);
414 cds_hlist_del(&e
->hlist
);
415 cds_list_del(&e
->node
);
420 * Enable/disable all callsites based on the state of a specific
422 * Must be called with tracepoint mutex held.
424 static void tracepoint_sync_callsites(const char *name
)
426 struct cds_hlist_head
*head
;
427 struct cds_hlist_node
*node
;
428 struct callsite_entry
*e
;
429 size_t name_len
= strlen(name
);
431 struct tracepoint_entry
*tp_entry
;
433 tp_entry
= get_tracepoint(name
);
434 if (name_len
> LTTNG_UST_SYM_NAME_LEN
- 1) {
435 WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name
, LTTNG_UST_SYM_NAME_LEN
- 1);
436 name_len
= LTTNG_UST_SYM_NAME_LEN
- 1;
438 hash
= jhash(name
, name_len
, 0);
439 head
= &callsite_table
[hash
& (CALLSITE_TABLE_SIZE
- 1)];
440 cds_hlist_for_each_entry(e
, node
, head
, hlist
) {
441 struct lttng_ust_tracepoint
*tp
= e
->tp
;
443 if (strncmp(name
, tp
->name
, LTTNG_UST_SYM_NAME_LEN
- 1))
446 set_tracepoint(&tp_entry
, tp
,
447 !!tp_entry
->refcount
);
449 disable_tracepoint(tp
);
455 * tracepoint_update_probe_range - Update a probe range
456 * @begin: beginning of the range
457 * @end: end of the range
459 * Updates the probe callback corresponding to a range of tracepoints.
462 void tracepoint_update_probe_range(struct lttng_ust_tracepoint
* const *begin
,
463 struct lttng_ust_tracepoint
* const *end
)
465 struct lttng_ust_tracepoint
* const *iter
;
466 struct tracepoint_entry
*mark_entry
;
468 for (iter
= begin
; iter
< end
; iter
++) {
470 continue; /* skip dummy */
471 if (!(*iter
)->name
) {
472 disable_tracepoint(*iter
);
475 mark_entry
= get_tracepoint((*iter
)->name
);
477 set_tracepoint(&mark_entry
, *iter
,
478 !!mark_entry
->refcount
);
480 disable_tracepoint(*iter
);
485 static void lib_update_tracepoints(struct tracepoint_lib
*lib
)
487 tracepoint_update_probe_range(lib
->tracepoints_start
,
488 lib
->tracepoints_start
+ lib
->tracepoints_count
);
491 static void lib_register_callsites(struct tracepoint_lib
*lib
)
493 struct lttng_ust_tracepoint
* const *begin
;
494 struct lttng_ust_tracepoint
* const *end
;
495 struct lttng_ust_tracepoint
* const *iter
;
497 begin
= lib
->tracepoints_start
;
498 end
= lib
->tracepoints_start
+ lib
->tracepoints_count
;
500 for (iter
= begin
; iter
< end
; iter
++) {
502 continue; /* skip dummy */
503 if (!(*iter
)->name
) {
506 add_callsite(lib
, *iter
);
510 static void lib_unregister_callsites(struct tracepoint_lib
*lib
)
512 struct callsite_entry
*callsite
, *tmp
;
514 cds_list_for_each_entry_safe(callsite
, tmp
, &lib
->callsites
, node
)
515 remove_callsite(callsite
);
519 * Update probes, removing the faulty probes.
521 static void tracepoint_update_probes(void)
523 struct tracepoint_lib
*lib
;
525 /* tracepoints registered from libraries and executable. */
526 cds_list_for_each_entry(lib
, &libs
, list
)
527 lib_update_tracepoints(lib
);
530 static struct lttng_ust_tracepoint_probe
*
531 tracepoint_add_probe(const char *name
, void (*probe
)(void), void *data
,
532 const char *signature
)
534 struct tracepoint_entry
*entry
;
535 struct lttng_ust_tracepoint_probe
*old
;
537 entry
= get_tracepoint(name
);
539 entry
= add_tracepoint(name
, signature
);
541 return (struct lttng_ust_tracepoint_probe
*)entry
;
543 old
= tracepoint_entry_add_probe(entry
, probe
, data
);
544 if (IS_ERR(old
) && !entry
->refcount
)
545 remove_tracepoint(entry
);
550 * __tracepoint_probe_register - Connect a probe to a tracepoint
551 * @name: tracepoint name
552 * @probe: probe handler
554 * Returns 0 if ok, error value on error.
555 * The probe address must at least be aligned on the architecture pointer size.
556 * Called with the tracepoint mutex held.
558 int __tracepoint_probe_register(const char *name
, void (*probe
)(void),
559 void *data
, const char *signature
)
564 DBG("Registering probe to tracepoint %s", name
);
566 pthread_mutex_lock(&tracepoint_mutex
);
567 old
= tracepoint_add_probe(name
, probe
, data
, signature
);
573 tracepoint_sync_callsites(name
);
576 pthread_mutex_unlock(&tracepoint_mutex
);
580 static void *tracepoint_remove_probe(const char *name
, void (*probe
)(void),
583 struct tracepoint_entry
*entry
;
586 entry
= get_tracepoint(name
);
588 return ERR_PTR(-ENOENT
);
589 old
= tracepoint_entry_remove_probe(entry
, probe
, data
);
592 if (!entry
->refcount
)
593 remove_tracepoint(entry
);
598 * tracepoint_probe_unregister - Disconnect a probe from a tracepoint
599 * @name: tracepoint name
600 * @probe: probe function pointer
601 * @probe: probe data pointer
603 int __tracepoint_probe_unregister(const char *name
, void (*probe
)(void),
609 DBG("Un-registering probe from tracepoint %s", name
);
611 pthread_mutex_lock(&tracepoint_mutex
);
612 old
= tracepoint_remove_probe(name
, probe
, data
);
617 tracepoint_sync_callsites(name
);
620 pthread_mutex_unlock(&tracepoint_mutex
);
624 static void tracepoint_add_old_probes(void *old
)
628 struct tp_probes
*tp_probes
= caa_container_of(old
,
629 struct tp_probes
, probes
[0]);
630 cds_list_add(&tp_probes
->u
.list
, &old_probes
);
635 * tracepoint_probe_register_noupdate - register a probe but not connect
636 * @name: tracepoint name
637 * @probe: probe handler
639 * caller must call tracepoint_probe_update_all()
641 int tracepoint_probe_register_noupdate(const char *name
, void (*probe
)(void),
642 void *data
, const char *signature
)
647 pthread_mutex_lock(&tracepoint_mutex
);
648 old
= tracepoint_add_probe(name
, probe
, data
, signature
);
653 tracepoint_add_old_probes(old
);
655 pthread_mutex_unlock(&tracepoint_mutex
);
660 * tracepoint_probe_unregister_noupdate - remove a probe but not disconnect
661 * @name: tracepoint name
662 * @probe: probe function pointer
664 * caller must call tracepoint_probe_update_all()
665 * Called with the tracepoint mutex held.
667 int tracepoint_probe_unregister_noupdate(const char *name
, void (*probe
)(void),
673 DBG("Un-registering probe from tracepoint %s", name
);
675 pthread_mutex_lock(&tracepoint_mutex
);
676 old
= tracepoint_remove_probe(name
, probe
, data
);
681 tracepoint_add_old_probes(old
);
683 pthread_mutex_unlock(&tracepoint_mutex
);
688 * tracepoint_probe_update_all - update tracepoints
690 void tracepoint_probe_update_all(void)
692 CDS_LIST_HEAD(release_probes
);
693 struct tp_probes
*pos
, *next
;
695 pthread_mutex_lock(&tracepoint_mutex
);
699 if (!cds_list_empty(&old_probes
))
700 cds_list_replace_init(&old_probes
, &release_probes
);
703 tracepoint_update_probes();
704 cds_list_for_each_entry_safe(pos
, next
, &release_probes
, u
.list
) {
705 cds_list_del(&pos
->u
.list
);
710 pthread_mutex_unlock(&tracepoint_mutex
);
713 void tracepoint_set_new_tracepoint_cb(void (*cb
)(struct lttng_ust_tracepoint
*))
715 new_tracepoint_cb
= cb
;
718 static void new_tracepoints(struct lttng_ust_tracepoint
* const *start
,
719 struct lttng_ust_tracepoint
* const *end
)
721 if (new_tracepoint_cb
) {
722 struct lttng_ust_tracepoint
* const *t
;
724 for (t
= start
; t
< end
; t
++) {
726 new_tracepoint_cb(*t
);
731 int tracepoint_register_lib(struct lttng_ust_tracepoint
* const *tracepoints_start
,
732 int tracepoints_count
)
734 struct tracepoint_lib
*pl
, *iter
;
738 pl
= (struct tracepoint_lib
*) zmalloc(sizeof(struct tracepoint_lib
));
740 PERROR("Unable to register tracepoint lib");
743 pl
->tracepoints_start
= tracepoints_start
;
744 pl
->tracepoints_count
= tracepoints_count
;
745 CDS_INIT_LIST_HEAD(&pl
->callsites
);
747 pthread_mutex_lock(&tracepoint_mutex
);
749 * We sort the libs by struct lib pointer address.
751 cds_list_for_each_entry_reverse(iter
, &libs
, list
) {
752 BUG_ON(iter
== pl
); /* Should never be in the list twice */
754 /* We belong to the location right after iter. */
755 cds_list_add(&pl
->list
, &iter
->list
);
759 /* We should be added at the head of the list */
760 cds_list_add(&pl
->list
, &libs
);
762 new_tracepoints(tracepoints_start
, tracepoints_start
+ tracepoints_count
);
763 lib_register_callsites(pl
);
764 lib_update_tracepoints(pl
);
765 pthread_mutex_unlock(&tracepoint_mutex
);
767 DBG("just registered a tracepoints section from %p and having %d tracepoints",
768 tracepoints_start
, tracepoints_count
);
772 for (i
= 0; i
< tracepoints_count
; i
++) {
773 DBG("registered tracepoint: %s", tracepoints_start
[i
]->name
);
780 int tracepoint_unregister_lib(struct lttng_ust_tracepoint
* const *tracepoints_start
)
782 struct tracepoint_lib
*lib
;
784 pthread_mutex_lock(&tracepoint_mutex
);
785 cds_list_for_each_entry(lib
, &libs
, list
) {
786 if (lib
->tracepoints_start
!= tracepoints_start
)
789 cds_list_del(&lib
->list
);
791 * Unregistering a callsite also decreases the
792 * callsite reference count of the corresponding
793 * tracepoint, and disables the tracepoint if
794 * the reference count drops to zero.
796 lib_unregister_callsites(lib
);
797 DBG("just unregistered a tracepoints section from %p",
798 lib
->tracepoints_start
);
802 pthread_mutex_unlock(&tracepoint_mutex
);
806 void init_tracepoint(void)
808 if (uatomic_xchg(&initialized
, 1) == 1)
813 void exit_tracepoint(void)
819 * Create the wrapper symbols.
821 #undef tp_rcu_read_lock_bp
822 #undef tp_rcu_read_unlock_bp
823 #undef tp_rcu_dereference_bp
825 void tp_rcu_read_lock_bp(void)
830 void tp_rcu_read_unlock_bp(void)
832 rcu_read_unlock_bp();
835 void *tp_rcu_dereference_sym_bp(void *p
)
837 return rcu_dereference_bp(p
);