[lttng-ust.git] / liblttng-ust-libc-wrapper / lttng-ust-malloc.c

/*
 * Copyright (C) 2009  Pierre-Marc Fournier
 * Copyright (C) 2011  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 */

#define _GNU_SOURCE
#include <lttng/ust-dlfcn.h>
#include <sys/types.h>
#include <stdio.h>
#include <assert.h>
#include <urcu/system.h>
#include <urcu/uatomic.h>
#include <urcu/compiler.h>
#include <urcu/tls-compat.h>
#include <urcu/arch.h>
#include <lttng/align.h>

#define TRACEPOINT_DEFINE
#define TRACEPOINT_CREATE_PROBES
#define TP_IP_PARAM ip
#include "ust_libc.h"

#define STATIC_CALLOC_LEN 4096
static char static_calloc_buf[STATIC_CALLOC_LEN];
static unsigned long static_calloc_buf_offset;

struct alloc_functions {
	void *(*calloc)(size_t nmemb, size_t size);
	void *(*malloc)(size_t size);
	void (*free)(void *ptr);
	void *(*realloc)(void *ptr, size_t size);
	void *(*memalign)(size_t alignment, size_t size);
	int (*posix_memalign)(void **memptr, size_t alignment, size_t size);
};

static
struct alloc_functions cur_alloc;

/*
 * Make sure our own use of the LTS compat layer will not cause infinite
 * recursion by calling calloc.
 */

static
void *static_calloc(size_t nmemb, size_t size);

/*
 * pthread mutex replacement for URCU tls compat layer.
 */
static int ust_malloc_lock;

static __attribute__((unused))
void ust_malloc_spin_lock(pthread_mutex_t *lock)
{
	/*
	 * The memory barrier within cmpxchg takes care of ordering
	 * memory accesses with respect to the start of the critical
	 * section.
	 */
	while (uatomic_cmpxchg(&ust_malloc_lock, 0, 1) != 0)
		caa_cpu_relax();
}

static __attribute__((unused))
void ust_malloc_spin_unlock(pthread_mutex_t *lock)
{
	/*
	 * Ensure memory accesses within the critical section do not
	 * leak outside.
	 */
	cmm_smp_mb();
	uatomic_set(&ust_malloc_lock, 0);
}

#define calloc static_calloc
#define pthread_mutex_lock ust_malloc_spin_lock
#define pthread_mutex_unlock ust_malloc_spin_unlock
static DEFINE_URCU_TLS(int, malloc_nesting);
#undef ust_malloc_spin_unlock
#undef ust_malloc_spin_lock
#undef calloc

/*
 * Static allocator to use when initially executing dlsym(). It keeps a
 * size_t value of each object size prior to the object.
 */
static
void *static_calloc_aligned(size_t nmemb, size_t size, size_t alignment)
{
	size_t prev_offset, new_offset, res_offset, aligned_offset;

	if (nmemb * size == 0) {
		return NULL;
	}

	/*
	 * Protect static_calloc_buf_offset from concurrent updates
	 * using a cmpxchg loop rather than a mutex to remove a
	 * dependency on pthread. This will minimize the risk of bad
	 * interaction between mutex and malloc instrumentation.
	 */
	res_offset = CMM_LOAD_SHARED(static_calloc_buf_offset);
	do {
		prev_offset = res_offset;
		aligned_offset = ALIGN(prev_offset + sizeof(size_t), alignment);
		new_offset = aligned_offset + nmemb * size;
		if (new_offset > sizeof(static_calloc_buf)) {
			abort();
		}
	} while ((res_offset = uatomic_cmpxchg(&static_calloc_buf_offset,
			prev_offset, new_offset)) != prev_offset);
	*(size_t *) &static_calloc_buf[aligned_offset - sizeof(size_t)] = size;
	return &static_calloc_buf[aligned_offset];
}

static
void *static_calloc(size_t nmemb, size_t size)
{
	void *retval;

	retval = static_calloc_aligned(nmemb, size, 1);
	return retval;
}

static
void *static_malloc(size_t size)
{
	void *retval;

	retval = static_calloc_aligned(1, size, 1);
	return retval;
}

static
void static_free(void *ptr)
{
	/* no-op. */
}

static
void *static_realloc(void *ptr, size_t size)
{
	size_t *old_size = NULL;
	void *retval;

	if (size == 0) {
		retval = NULL;
		goto end;
	}

	if (ptr) {
		old_size = (size_t *) ptr - 1;
		if (size <= *old_size) {
			/* We can re-use the old entry. */
			*old_size = size;
			retval = ptr;
			goto end;
		}
	}
	/* We need to expand. Don't free previous memory location. */
	retval = static_calloc_aligned(1, size, 1);
	assert(retval);
	if (ptr)
		memcpy(retval, ptr, *old_size);
end:
	return retval;
}

static
void *static_memalign(size_t alignment, size_t size)
{
	void *retval;

	retval = static_calloc_aligned(1, size, alignment);
	return retval;
}

static
int static_posix_memalign(void **memptr, size_t alignment, size_t size)
{
	void *ptr;

	/* Check for power of 2, larger than void *. */
	if (alignment & (alignment - 1)
			|| alignment < sizeof(void *)
			|| alignment == 0) {
		goto end;
	}
	ptr = static_calloc_aligned(1, size, alignment);
	*memptr = ptr;
end:
	return 0;
}

static
void setup_static_allocator(void)
{
	assert(cur_alloc.calloc == NULL);
	cur_alloc.calloc = static_calloc;
	assert(cur_alloc.malloc == NULL);
	cur_alloc.malloc = static_malloc;
	assert(cur_alloc.free == NULL);
	cur_alloc.free = static_free;
	assert(cur_alloc.realloc == NULL);
	cur_alloc.realloc = static_realloc;
	assert(cur_alloc.memalign == NULL);
	cur_alloc.memalign = static_memalign;
	assert(cur_alloc.posix_memalign == NULL);
	cur_alloc.posix_memalign = static_posix_memalign;
}

static
void lookup_all_symbols(void)
{
	struct alloc_functions af;

	/*
	 * Temporarily redirect allocation functions to
	 * static_calloc_aligned, and free function to static_free
	 * (no-op), until the dlsym lookup has completed.
	 */
	setup_static_allocator();

	/* Perform the actual lookups */
	af.calloc = dlsym(RTLD_NEXT, "calloc");
	af.malloc = dlsym(RTLD_NEXT, "malloc");
	af.free = dlsym(RTLD_NEXT, "free");
	af.realloc = dlsym(RTLD_NEXT, "realloc");
	af.memalign = dlsym(RTLD_NEXT, "memalign");
	af.posix_memalign = dlsym(RTLD_NEXT, "posix_memalign");

	/* Populate the new allocator functions */
	memcpy(&cur_alloc, &af, sizeof(cur_alloc));
}

void *malloc(size_t size)
{
	void *retval;

	URCU_TLS(malloc_nesting)++;
	if (cur_alloc.malloc == NULL) {
		lookup_all_symbols();
		if (cur_alloc.malloc == NULL) {
			fprintf(stderr, "mallocwrap: unable to find malloc\n");
			abort();
		}
	}
	retval = cur_alloc.malloc(size);
	if (URCU_TLS(malloc_nesting) == 1) {
		tracepoint(ust_libc, malloc, size, retval,
			__builtin_return_address(0));
	}
	URCU_TLS(malloc_nesting)--;
	return retval;
}

void free(void *ptr)
{
	URCU_TLS(malloc_nesting)++;
	/*
	 * Check whether the memory was allocated with
	 * static_calloc_align, in which case there is nothing to free.
	 */
	if (caa_unlikely((char *)ptr >= static_calloc_buf &&
			(char *)ptr < static_calloc_buf + STATIC_CALLOC_LEN)) {
		goto end;
	}

	if (URCU_TLS(malloc_nesting) == 1) {
		tracepoint(ust_libc, free, ptr,
			__builtin_return_address(0));
	}

	if (cur_alloc.free == NULL) {
		lookup_all_symbols();
		if (cur_alloc.free == NULL) {
			fprintf(stderr, "mallocwrap: unable to find free\n");
			abort();
		}
	}
	cur_alloc.free(ptr);
end:
	URCU_TLS(malloc_nesting)--;
}

void *calloc(size_t nmemb, size_t size)
{
	void *retval;

	URCU_TLS(malloc_nesting)++;
	if (cur_alloc.calloc == NULL) {
		lookup_all_symbols();
		if (cur_alloc.calloc == NULL) {
			fprintf(stderr, "callocwrap: unable to find calloc\n");
			abort();
		}
	}
	retval = cur_alloc.calloc(nmemb, size);
	if (URCU_TLS(malloc_nesting) == 1) {
		tracepoint(ust_libc, calloc, nmemb, size, retval,
			__builtin_return_address(0));
	}
	URCU_TLS(malloc_nesting)--;
	return retval;
}

void *realloc(void *ptr, size_t size)
{
	void *retval;

	URCU_TLS(malloc_nesting)++;
	/*
	 * Check whether the memory was allocated with
	 * static_calloc_align, in which case there is nothing
	 * to free, and we need to copy the old data.
	 */
	if (caa_unlikely((char *)ptr >= static_calloc_buf &&
			(char *)ptr < static_calloc_buf + STATIC_CALLOC_LEN)) {
		size_t *old_size;

		old_size = (size_t *) ptr - 1;
		if (cur_alloc.calloc == NULL) {
			lookup_all_symbols();
			if (cur_alloc.calloc == NULL) {
				fprintf(stderr, "reallocwrap: unable to find calloc\n");
				abort();
			}
		}
		retval = cur_alloc.calloc(1, size);
		if (retval) {
			memcpy(retval, ptr, *old_size);
		}
		/*
		 * Mimick that a NULL pointer has been received, so
		 * memory allocation analysis based on the trace don't
		 * get confused by the address from the static
		 * allocator.
		 */
		ptr = NULL;
		goto end;
	}

	if (cur_alloc.realloc == NULL) {
		lookup_all_symbols();
		if (cur_alloc.realloc == NULL) {
			fprintf(stderr, "reallocwrap: unable to find realloc\n");
			abort();
		}
	}
	retval = cur_alloc.realloc(ptr, size);
end:
	if (URCU_TLS(malloc_nesting) == 1) {
		tracepoint(ust_libc, realloc, ptr, size, retval,
			__builtin_return_address(0));
	}
	URCU_TLS(malloc_nesting)--;
	return retval;
}

void *memalign(size_t alignment, size_t size)
{
	void *retval;

	URCU_TLS(malloc_nesting)++;
	if (cur_alloc.memalign == NULL) {
		lookup_all_symbols();
		if (cur_alloc.memalign == NULL) {
			fprintf(stderr, "memalignwrap: unable to find memalign\n");
			abort();
		}
	}
	retval = cur_alloc.memalign(alignment, size);
	if (URCU_TLS(malloc_nesting) == 1) {
		tracepoint(ust_libc, memalign, alignment, size, retval,
			__builtin_return_address(0));
	}
	URCU_TLS(malloc_nesting)--;
	return retval;
}

int posix_memalign(void **memptr, size_t alignment, size_t size)
{
	int retval;

	URCU_TLS(malloc_nesting)++;
	if (cur_alloc.posix_memalign == NULL) {
		lookup_all_symbols();
		if (cur_alloc.posix_memalign == NULL) {
			fprintf(stderr, "posix_memalignwrap: unable to find posix_memalign\n");
			abort();
		}
	}
	retval = cur_alloc.posix_memalign(memptr, alignment, size);
	if (URCU_TLS(malloc_nesting) == 1) {
		tracepoint(ust_libc, posix_memalign, *memptr, alignment, size,
			retval, __builtin_return_address(0));
	}
	URCU_TLS(malloc_nesting)--;
	return retval;
}

__attribute__((constructor))
void lttng_ust_malloc_wrapper_init(void)
{
	/* Initialization already done */
	if (cur_alloc.calloc) {
		return;
	}
	/*
	 * Ensure the allocator is in place before the process becomes
	 * multithreaded.
	 */
	lookup_all_symbols();
}
Commit	Line	Data
b27f8e75 MD	1	/*
b27f8e75 MD	2	* Copyright (C) 2009 Pierre-Marc Fournier
1622ba22	3	* Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
c39c72ee PMF	4	*
	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; either
	8	* version 2.1 of the License, or (at your option) any later version.
	9	*
	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.
	14	*
	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
	18	*/
	19
e541a28d	20	#define _GNU_SOURCE
f02baefb	21	#include <lttng/ust-dlfcn.h>
e541a28d PMF	22	#include <sys/types.h>
e541a28d PMF	23	#include <stdio.h>
2594a5b4	24	#include <assert.h>
4c3536e0 MD	25	#include <urcu/system.h>
4c3536e0 MD	26	#include <urcu/uatomic.h>
2594a5b4	27	#include <urcu/compiler.h>
8c06ba6f	28	#include <urcu/tls-compat.h>
20ef5166	29	#include <urcu/arch.h>
2594a5b4	30	#include <lttng/align.h>
1622ba22 MD	31
	32	#define TRACEPOINT_DEFINE
	33	#define TRACEPOINT_CREATE_PROBES
b221a2d2	34	#define TP_IP_PARAM ip
1622ba22	35	#include "ust_libc.h"
fbd8191b	36
f95b2888 SS	37	#define STATIC_CALLOC_LEN 4096
f95b2888 SS	38	static char static_calloc_buf[STATIC_CALLOC_LEN];
4c3536e0	39	static unsigned long static_calloc_buf_offset;
f95b2888	40
2594a5b4 MD	41	struct alloc_functions {
	42	void (calloc)(size_t nmemb, size_t size);
	43	void (malloc)(size_t size);
	44	void (free)(void ptr);
	45	void (realloc)(void *ptr, size_t size);
	46	void (memalign)(size_t alignment, size_t size);
	47	int (posix_memalign)(void *memptr, size_t alignment, size_t size);
	48	};
	49
	50	static
	51	struct alloc_functions cur_alloc;
	52
8c06ba6f MD	53	/*
	54	* Make sure our own use of the LTS compat layer will not cause infinite
	55	* recursion by calling calloc.
	56	*/
	57
	58	static
	59	void *static_calloc(size_t nmemb, size_t size);
	60
20ef5166 MD	61	/*
	62	* pthread mutex replacement for URCU tls compat layer.
	63	*/
	64	static int ust_malloc_lock;
	65
	66	static __attribute__((unused))
	67	void ust_malloc_spin_lock(pthread_mutex_t *lock)
	68	{
	69	/*
	70	* The memory barrier within cmpxchg takes care of ordering
	71	* memory accesses with respect to the start of the critical
	72	* section.
	73	*/
	74	while (uatomic_cmpxchg(&ust_malloc_lock, 0, 1) != 0)
	75	caa_cpu_relax();
	76	}
	77
	78	static __attribute__((unused))
	79	void ust_malloc_spin_unlock(pthread_mutex_t *lock)
	80	{
	81	/*
	82	* Ensure memory accesses within the critical section do not
	83	* leak outside.
	84	*/
	85	cmm_smp_mb();
	86	uatomic_set(&ust_malloc_lock, 0);
	87	}
	88
8c06ba6f	89	#define calloc static_calloc
20ef5166 MD	90	#define pthread_mutex_lock ust_malloc_spin_lock
20ef5166 MD	91	#define pthread_mutex_unlock ust_malloc_spin_unlock
8c06ba6f	92	static DEFINE_URCU_TLS(int, malloc_nesting);
20ef5166 MD	93	#undef ust_malloc_spin_unlock
20ef5166 MD	94	#undef ust_malloc_spin_lock
8c06ba6f MD	95	#undef calloc
8c06ba6f MD	96
2594a5b4 MD	97	/*
	98	* Static allocator to use when initially executing dlsym(). It keeps a
	99	* size_t value of each object size prior to the object.
	100	*/
	101	static
	102	void *static_calloc_aligned(size_t nmemb, size_t size, size_t alignment)
f95b2888	103	{
2594a5b4 MD	104	size_t prev_offset, new_offset, res_offset, aligned_offset;
	105
	106	if (nmemb * size == 0) {
	107	return NULL;
	108	}
f95b2888	109
4c3536e0 MD	110	/*
	111	* Protect static_calloc_buf_offset from concurrent updates
	112	* using a cmpxchg loop rather than a mutex to remove a
	113	* dependency on pthread. This will minimize the risk of bad
	114	* interaction between mutex and malloc instrumentation.
	115	*/
	116	res_offset = CMM_LOAD_SHARED(static_calloc_buf_offset);
	117	do {
	118	prev_offset = res_offset;
2594a5b4 MD	119	aligned_offset = ALIGN(prev_offset + sizeof(size_t), alignment);
	120	new_offset = aligned_offset + nmemb * size;
	121	if (new_offset > sizeof(static_calloc_buf)) {
	122	abort();
4c3536e0	123	}
4c3536e0 MD	124	} while ((res_offset = uatomic_cmpxchg(&static_calloc_buf_offset,
4c3536e0 MD	125	prev_offset, new_offset)) != prev_offset);
2594a5b4 MD	126	(size_t ) &static_calloc_buf[aligned_offset - sizeof(size_t)] = size;
	127	return &static_calloc_buf[aligned_offset];
	128	}
	129
	130	static
	131	void *static_calloc(size_t nmemb, size_t size)
	132	{
	133	void *retval;
	134
	135	retval = static_calloc_aligned(nmemb, size, 1);
2594a5b4 MD	136	return retval;
	137	}
	138
	139	static
	140	void *static_malloc(size_t size)
	141	{
	142	void *retval;
	143
	144	retval = static_calloc_aligned(1, size, 1);
2594a5b4 MD	145	return retval;
	146	}
	147
	148	static
	149	void static_free(void *ptr)
	150	{
	151	/* no-op. */
2594a5b4 MD	152	}
	153
	154	static
	155	void static_realloc(void ptr, size_t size)
	156	{
	157	size_t *old_size = NULL;
	158	void *retval;
	159
	160	if (size == 0) {
	161	retval = NULL;
	162	goto end;
	163	}
	164
	165	if (ptr) {
	166	old_size = (size_t *) ptr - 1;
	167	if (size <= *old_size) {
	168	/* We can re-use the old entry. */
	169	*old_size = size;
	170	retval = ptr;
	171	goto end;
	172	}
	173	}
	174	/* We need to expand. Don't free previous memory location. */
	175	retval = static_calloc_aligned(1, size, 1);
	176	assert(retval);
	177	if (ptr)
	178	memcpy(retval, ptr, *old_size);
	179	end:
2594a5b4 MD	180	return retval;
	181	}
	182
	183	static
	184	void *static_memalign(size_t alignment, size_t size)
	185	{
	186	void *retval;
	187
	188	retval = static_calloc_aligned(1, size, alignment);
2594a5b4 MD	189	return retval;
	190	}
	191
	192	static
	193	int static_posix_memalign(void **memptr, size_t alignment, size_t size)
	194	{
2594a5b4 MD	195	void *ptr;
	196
	197	/* Check for power of 2, larger than void . /
	198	if (alignment & (alignment - 1)
	199	\|\| alignment < sizeof(void *)
	200	\|\| alignment == 0) {
2594a5b4 MD	201	goto end;
	202	}
	203	ptr = static_calloc_aligned(1, size, alignment);
	204	*memptr = ptr;
2594a5b4	205	end:
2594a5b4 MD	206	return 0;
	207	}
	208
	209	static
	210	void setup_static_allocator(void)
	211	{
	212	assert(cur_alloc.calloc == NULL);
	213	cur_alloc.calloc = static_calloc;
	214	assert(cur_alloc.malloc == NULL);
	215	cur_alloc.malloc = static_malloc;
	216	assert(cur_alloc.free == NULL);
	217	cur_alloc.free = static_free;
	218	assert(cur_alloc.realloc == NULL);
	219	cur_alloc.realloc = static_realloc;
	220	assert(cur_alloc.memalign == NULL);
	221	cur_alloc.memalign = static_memalign;
	222	assert(cur_alloc.posix_memalign == NULL);
	223	cur_alloc.posix_memalign = static_posix_memalign;
	224	}
	225
	226	static
	227	void lookup_all_symbols(void)
	228	{
	229	struct alloc_functions af;
	230
	231	/*
	232	* Temporarily redirect allocation functions to
	233	* static_calloc_aligned, and free function to static_free
	234	* (no-op), until the dlsym lookup has completed.
	235	*/
	236	setup_static_allocator();
	237
	238	/* Perform the actual lookups */
	239	af.calloc = dlsym(RTLD_NEXT, "calloc");
	240	af.malloc = dlsym(RTLD_NEXT, "malloc");
	241	af.free = dlsym(RTLD_NEXT, "free");
	242	af.realloc = dlsym(RTLD_NEXT, "realloc");
	243	af.memalign = dlsym(RTLD_NEXT, "memalign");
	244	af.posix_memalign = dlsym(RTLD_NEXT, "posix_memalign");
	245
	246	/* Populate the new allocator functions */
	247	memcpy(&cur_alloc, &af, sizeof(cur_alloc));
f95b2888 SS	248	}
f95b2888 SS	249
e541a28d PMF	250	void *malloc(size_t size)
e541a28d PMF	251	{
1c184644 PMF	252	void *retval;
1c184644 PMF	253
8c06ba6f	254	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	255	if (cur_alloc.malloc == NULL) {
	256	lookup_all_symbols();
	257	if (cur_alloc.malloc == NULL) {
e541a28d	258	fprintf(stderr, "mallocwrap: unable to find malloc\n");
2594a5b4	259	abort();
e541a28d PMF	260	}
e541a28d PMF	261	}
2594a5b4	262	retval = cur_alloc.malloc(size);
8c06ba6f	263	if (URCU_TLS(malloc_nesting) == 1) {
b221a2d2 MD	264	tracepoint(ust_libc, malloc, size, retval,
b221a2d2 MD	265	__builtin_return_address(0));
8c06ba6f MD	266	}
8c06ba6f MD	267	URCU_TLS(malloc_nesting)--;
1c184644 PMF	268	return retval;
	269	}
	270
	271	void free(void *ptr)
	272	{
8c06ba6f	273	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	274	/*
	275	* Check whether the memory was allocated with
	276	* static_calloc_align, in which case there is nothing to free.
f95b2888	277	*/
2594a5b4 MD	278	if (caa_unlikely((char *)ptr >= static_calloc_buf &&
2594a5b4 MD	279	(char *)ptr < static_calloc_buf + STATIC_CALLOC_LEN)) {
8c06ba6f MD	280	goto end;
	281	}
	282
	283	if (URCU_TLS(malloc_nesting) == 1) {
b221a2d2 MD	284	tracepoint(ust_libc, free, ptr,
b221a2d2 MD	285	__builtin_return_address(0));
f95b2888	286	}
1c184644	287
2594a5b4 MD	288	if (cur_alloc.free == NULL) {
	289	lookup_all_symbols();
	290	if (cur_alloc.free == NULL) {
1c184644	291	fprintf(stderr, "mallocwrap: unable to find free\n");
2594a5b4	292	abort();
1c184644 PMF	293	}
1c184644 PMF	294	}
2594a5b4	295	cur_alloc.free(ptr);
8c06ba6f MD	296	end:
8c06ba6f MD	297	URCU_TLS(malloc_nesting)--;
e541a28d	298	}
f95b2888 SS	299
	300	void *calloc(size_t nmemb, size_t size)
	301	{
f95b2888 SS	302	void *retval;
f95b2888 SS	303
8c06ba6f	304	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	305	if (cur_alloc.calloc == NULL) {
	306	lookup_all_symbols();
	307	if (cur_alloc.calloc == NULL) {
f95b2888	308	fprintf(stderr, "callocwrap: unable to find calloc\n");
2594a5b4	309	abort();
f95b2888 SS	310	}
f95b2888 SS	311	}
2594a5b4	312	retval = cur_alloc.calloc(nmemb, size);
8c06ba6f	313	if (URCU_TLS(malloc_nesting) == 1) {
b221a2d2 MD	314	tracepoint(ust_libc, calloc, nmemb, size, retval,
b221a2d2 MD	315	__builtin_return_address(0));
8c06ba6f MD	316	}
8c06ba6f MD	317	URCU_TLS(malloc_nesting)--;
f95b2888 SS	318	return retval;
	319	}
	320
	321	void realloc(void ptr, size_t size)
	322	{
f95b2888 SS	323	void *retval;
f95b2888 SS	324
8c06ba6f MD	325	URCU_TLS(malloc_nesting)++;
	326	/*
	327	* Check whether the memory was allocated with
2594a5b4 MD	328	* static_calloc_align, in which case there is nothing
	329	* to free, and we need to copy the old data.
	330	*/
	331	if (caa_unlikely((char *)ptr >= static_calloc_buf &&
	332	(char *)ptr < static_calloc_buf + STATIC_CALLOC_LEN)) {
	333	size_t *old_size;
	334
	335	old_size = (size_t *) ptr - 1;
	336	if (cur_alloc.calloc == NULL) {
	337	lookup_all_symbols();
	338	if (cur_alloc.calloc == NULL) {
	339	fprintf(stderr, "reallocwrap: unable to find calloc\n");
	340	abort();
	341	}
	342	}
	343	retval = cur_alloc.calloc(1, size);
	344	if (retval) {
	345	memcpy(retval, ptr, *old_size);
	346	}
8c06ba6f MD	347	/*
	348	* Mimick that a NULL pointer has been received, so
	349	* memory allocation analysis based on the trace don't
	350	* get confused by the address from the static
	351	* allocator.
	352	*/
	353	ptr = NULL;
2594a5b4 MD	354	goto end;
	355	}
	356
	357	if (cur_alloc.realloc == NULL) {
	358	lookup_all_symbols();
	359	if (cur_alloc.realloc == NULL) {
f95b2888	360	fprintf(stderr, "reallocwrap: unable to find realloc\n");
2594a5b4	361	abort();
f95b2888 SS	362	}
f95b2888 SS	363	}
2594a5b4 MD	364	retval = cur_alloc.realloc(ptr, size);
2594a5b4 MD	365	end:
8c06ba6f	366	if (URCU_TLS(malloc_nesting) == 1) {
b221a2d2 MD	367	tracepoint(ust_libc, realloc, ptr, size, retval,
b221a2d2 MD	368	__builtin_return_address(0));
8c06ba6f MD	369	}
8c06ba6f MD	370	URCU_TLS(malloc_nesting)--;
f95b2888 SS	371	return retval;
f95b2888 SS	372	}
9d34b226 SS	373
	374	void *memalign(size_t alignment, size_t size)
	375	{
9d34b226 SS	376	void *retval;
9d34b226 SS	377
8c06ba6f	378	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	379	if (cur_alloc.memalign == NULL) {
	380	lookup_all_symbols();
	381	if (cur_alloc.memalign == NULL) {
9d34b226	382	fprintf(stderr, "memalignwrap: unable to find memalign\n");
2594a5b4	383	abort();
9d34b226 SS	384	}
9d34b226 SS	385	}
2594a5b4	386	retval = cur_alloc.memalign(alignment, size);
8c06ba6f	387	if (URCU_TLS(malloc_nesting) == 1) {
b221a2d2 MD	388	tracepoint(ust_libc, memalign, alignment, size, retval,
b221a2d2 MD	389	__builtin_return_address(0));
8c06ba6f MD	390	}
8c06ba6f MD	391	URCU_TLS(malloc_nesting)--;
9d34b226 SS	392	return retval;
	393	}
	394
	395	int posix_memalign(void **memptr, size_t alignment, size_t size)
	396	{
9d34b226 SS	397	int retval;
9d34b226 SS	398
8c06ba6f	399	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	400	if (cur_alloc.posix_memalign == NULL) {
	401	lookup_all_symbols();
	402	if (cur_alloc.posix_memalign == NULL) {
9d34b226	403	fprintf(stderr, "posix_memalignwrap: unable to find posix_memalign\n");
2594a5b4	404	abort();
9d34b226 SS	405	}
9d34b226 SS	406	}
2594a5b4	407	retval = cur_alloc.posix_memalign(memptr, alignment, size);
8c06ba6f MD	408	if (URCU_TLS(malloc_nesting) == 1) {
8c06ba6f MD	409	tracepoint(ust_libc, posix_memalign, *memptr, alignment, size,
b221a2d2	410	retval, __builtin_return_address(0));
8c06ba6f MD	411	}
8c06ba6f MD	412	URCU_TLS(malloc_nesting)--;
9d34b226 SS	413	return retval;
9d34b226 SS	414	}
2594a5b4 MD	415
	416	__attribute__((constructor))
	417	void lttng_ust_malloc_wrapper_init(void)
	418	{
	419	/* Initialization already done */
	420	if (cur_alloc.calloc) {
	421	return;
	422	}
	423	/*
	424	* Ensure the allocator is in place before the process becomes
	425	* multithreaded.
	426	*/
	427	lookup_all_symbols();
	428	}