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

/*
 * SPDX-License-Identifier: LGPL-2.1-or-later
 *
 * Copyright (C) 2009 Pierre-Marc Fournier
 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

/*
 * Do _not_ define _LGPL_SOURCE because we don't want to create a
 * circular dependency loop between this malloc wrapper, liburcu and
 * libc.
 */
#include <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 <ust-helper.h>
#include "ust-compat.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
void ust_malloc_spin_lock(pthread_mutex_t *lock)
	__attribute__((unused));
static
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
void ust_malloc_spin_unlock(pthread_mutex_t *lock)
	__attribute__((unused));
static
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 pthread_mutex_unlock
#undef pthread_mutex_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 = LTTNG_UST_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(lttng_ust_libc, malloc,
			size, retval, LTTNG_UST_CALLER_IP());
	}
	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(lttng_ust_libc, free,
			ptr, LTTNG_UST_CALLER_IP());
	}

	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(lttng_ust_libc, calloc,
			nmemb, size, retval, LTTNG_UST_CALLER_IP());
	}
	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(lttng_ust_libc, realloc,
			ptr, size, retval, LTTNG_UST_CALLER_IP());
	}
	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(lttng_ust_libc, memalign,
			alignment, size, retval,
			LTTNG_UST_CALLER_IP());
	}
	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(lttng_ust_libc, posix_memalign,
			*memptr, alignment, size,
			retval, LTTNG_UST_CALLER_IP());
	}
	URCU_TLS(malloc_nesting)--;
	return retval;
}

static
void lttng_ust_fixup_malloc_nesting_tls(void)
{
	asm volatile ("" : : "m" (URCU_TLS(malloc_nesting)));
}

void lttng_ust_libc_wrapper_malloc_init(void)
{
	/* Initialization already done */
	if (cur_alloc.calloc) {
		return;
	}
	lttng_ust_fixup_malloc_nesting_tls();
	/*
	 * Ensure the allocator is in place before the process becomes
	 * multithreaded.
	 */
	lookup_all_symbols();
}
Commit	Line	Data
b27f8e75	1	/*
c0c0989a	2	* SPDX-License-Identifier: LGPL-2.1-or-later
c39c72ee	3	*
c0c0989a MJ	4	* Copyright (C) 2009 Pierre-Marc Fournier
c0c0989a MJ	5	* Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
c39c72ee PMF	6	*/
c39c72ee PMF	7
d7e89462 MD	8	/*
	9	* Do _not_ define _LGPL_SOURCE because we don't want to create a
	10	* circular dependency loop between this malloc wrapper, liburcu and
	11	* libc.
	12	*/
ae4b659d	13	#include <ust-dlfcn.h>
e541a28d PMF	14	#include <sys/types.h>
e541a28d PMF	15	#include <stdio.h>
2594a5b4	16	#include <assert.h>
4c3536e0 MD	17	#include <urcu/system.h>
4c3536e0 MD	18	#include <urcu/uatomic.h>
2594a5b4	19	#include <urcu/compiler.h>
8c06ba6f	20	#include <urcu/tls-compat.h>
20ef5166	21	#include <urcu/arch.h>
864a1eda	22	#include <ust-helper.h>
cd61d9bf	23	#include "ust-compat.h"
1622ba22 MD	24
	25	#define TRACEPOINT_DEFINE
	26	#define TRACEPOINT_CREATE_PROBES
52c95399	27	#define TP_IP_PARAM ip
1622ba22	28	#include "ust_libc.h"
fbd8191b	29
f95b2888 SS	30	#define STATIC_CALLOC_LEN 4096
f95b2888 SS	31	static char static_calloc_buf[STATIC_CALLOC_LEN];
4c3536e0	32	static unsigned long static_calloc_buf_offset;
f95b2888	33
2594a5b4 MD	34	struct alloc_functions {
	35	void (calloc)(size_t nmemb, size_t size);
	36	void (malloc)(size_t size);
	37	void (free)(void ptr);
	38	void (realloc)(void *ptr, size_t size);
	39	void (memalign)(size_t alignment, size_t size);
	40	int (posix_memalign)(void *memptr, size_t alignment, size_t size);
	41	};
	42
	43	static
	44	struct alloc_functions cur_alloc;
	45
8c06ba6f MD	46	/*
	47	* Make sure our own use of the LTS compat layer will not cause infinite
	48	* recursion by calling calloc.
	49	*/
	50
	51	static
	52	void *static_calloc(size_t nmemb, size_t size);
	53
20ef5166 MD	54	/*
	55	* pthread mutex replacement for URCU tls compat layer.
	56	*/
	57	static int ust_malloc_lock;
	58
8da9deee MJ	59	static
	60	void ust_malloc_spin_lock(pthread_mutex_t *lock)
	61	__attribute__((unused));
	62	static
20ef5166 MD	63	void ust_malloc_spin_lock(pthread_mutex_t *lock)
	64	{
	65	/*
	66	* The memory barrier within cmpxchg takes care of ordering
	67	* memory accesses with respect to the start of the critical
	68	* section.
	69	*/
	70	while (uatomic_cmpxchg(&ust_malloc_lock, 0, 1) != 0)
	71	caa_cpu_relax();
	72	}
	73
8da9deee MJ	74	static
	75	void ust_malloc_spin_unlock(pthread_mutex_t *lock)
	76	__attribute__((unused));
	77	static
20ef5166 MD	78	void ust_malloc_spin_unlock(pthread_mutex_t *lock)
	79	{
	80	/*
	81	* Ensure memory accesses within the critical section do not
	82	* leak outside.
	83	*/
	84	cmm_smp_mb();
	85	uatomic_set(&ust_malloc_lock, 0);
	86	}
	87
8c06ba6f	88	#define calloc static_calloc
20ef5166 MD	89	#define pthread_mutex_lock ust_malloc_spin_lock
20ef5166 MD	90	#define pthread_mutex_unlock ust_malloc_spin_unlock
16adecf1	91	static DEFINE_URCU_TLS(int, malloc_nesting);
50170875 CB	92	#undef pthread_mutex_unlock
50170875 CB	93	#undef pthread_mutex_lock
8c06ba6f MD	94	#undef calloc
8c06ba6f MD	95
2594a5b4 MD	96	/*
	97	* Static allocator to use when initially executing dlsym(). It keeps a
	98	* size_t value of each object size prior to the object.
	99	*/
	100	static
	101	void *static_calloc_aligned(size_t nmemb, size_t size, size_t alignment)
f95b2888	102	{
2594a5b4 MD	103	size_t prev_offset, new_offset, res_offset, aligned_offset;
	104
	105	if (nmemb * size == 0) {
	106	return NULL;
	107	}
f95b2888	108
4c3536e0 MD	109	/*
	110	* Protect static_calloc_buf_offset from concurrent updates
	111	* using a cmpxchg loop rather than a mutex to remove a
	112	* dependency on pthread. This will minimize the risk of bad
	113	* interaction between mutex and malloc instrumentation.
	114	*/
	115	res_offset = CMM_LOAD_SHARED(static_calloc_buf_offset);
	116	do {
	117	prev_offset = res_offset;
b72687b8	118	aligned_offset = LTTNG_UST_ALIGN(prev_offset + sizeof(size_t), alignment);
2594a5b4 MD	119	new_offset = aligned_offset + nmemb * size;
	120	if (new_offset > sizeof(static_calloc_buf)) {
	121	abort();
4c3536e0	122	}
4c3536e0 MD	123	} while ((res_offset = uatomic_cmpxchg(&static_calloc_buf_offset,
4c3536e0 MD	124	prev_offset, new_offset)) != prev_offset);
2594a5b4 MD	125	(size_t ) &static_calloc_buf[aligned_offset - sizeof(size_t)] = size;
	126	return &static_calloc_buf[aligned_offset];
	127	}
	128
	129	static
	130	void *static_calloc(size_t nmemb, size_t size)
	131	{
	132	void *retval;
	133
	134	retval = static_calloc_aligned(nmemb, size, 1);
2594a5b4 MD	135	return retval;
	136	}
	137
	138	static
	139	void *static_malloc(size_t size)
	140	{
	141	void *retval;
	142
	143	retval = static_calloc_aligned(1, size, 1);
2594a5b4 MD	144	return retval;
	145	}
	146
	147	static
	148	void static_free(void *ptr)
	149	{
	150	/* no-op. */
2594a5b4 MD	151	}
	152
	153	static
	154	void static_realloc(void ptr, size_t size)
	155	{
	156	size_t *old_size = NULL;
	157	void *retval;
	158
	159	if (size == 0) {
	160	retval = NULL;
	161	goto end;
	162	}
	163
	164	if (ptr) {
	165	old_size = (size_t *) ptr - 1;
	166	if (size <= *old_size) {
	167	/* We can re-use the old entry. */
	168	*old_size = size;
	169	retval = ptr;
	170	goto end;
	171	}
	172	}
	173	/* We need to expand. Don't free previous memory location. */
	174	retval = static_calloc_aligned(1, size, 1);
	175	assert(retval);
	176	if (ptr)
	177	memcpy(retval, ptr, *old_size);
	178	end:
2594a5b4 MD	179	return retval;
	180	}
	181
	182	static
	183	void *static_memalign(size_t alignment, size_t size)
	184	{
	185	void *retval;
	186
	187	retval = static_calloc_aligned(1, size, alignment);
2594a5b4 MD	188	return retval;
	189	}
	190
	191	static
	192	int static_posix_memalign(void **memptr, size_t alignment, size_t size)
	193	{
2594a5b4 MD	194	void *ptr;
	195
	196	/* Check for power of 2, larger than void . /
	197	if (alignment & (alignment - 1)
	198	\|\| alignment < sizeof(void *)
	199	\|\| alignment == 0) {
2594a5b4 MD	200	goto end;
	201	}
	202	ptr = static_calloc_aligned(1, size, alignment);
	203	*memptr = ptr;
2594a5b4	204	end:
2594a5b4 MD	205	return 0;
	206	}
	207
	208	static
	209	void setup_static_allocator(void)
	210	{
	211	assert(cur_alloc.calloc == NULL);
	212	cur_alloc.calloc = static_calloc;
	213	assert(cur_alloc.malloc == NULL);
	214	cur_alloc.malloc = static_malloc;
	215	assert(cur_alloc.free == NULL);
	216	cur_alloc.free = static_free;
	217	assert(cur_alloc.realloc == NULL);
	218	cur_alloc.realloc = static_realloc;
	219	assert(cur_alloc.memalign == NULL);
	220	cur_alloc.memalign = static_memalign;
	221	assert(cur_alloc.posix_memalign == NULL);
	222	cur_alloc.posix_memalign = static_posix_memalign;
	223	}
	224
	225	static
	226	void lookup_all_symbols(void)
	227	{
	228	struct alloc_functions af;
	229
	230	/*
	231	* Temporarily redirect allocation functions to
	232	* static_calloc_aligned, and free function to static_free
	233	* (no-op), until the dlsym lookup has completed.
	234	*/
	235	setup_static_allocator();
	236
	237	/* Perform the actual lookups */
	238	af.calloc = dlsym(RTLD_NEXT, "calloc");
	239	af.malloc = dlsym(RTLD_NEXT, "malloc");
	240	af.free = dlsym(RTLD_NEXT, "free");
	241	af.realloc = dlsym(RTLD_NEXT, "realloc");
	242	af.memalign = dlsym(RTLD_NEXT, "memalign");
	243	af.posix_memalign = dlsym(RTLD_NEXT, "posix_memalign");
	244
	245	/* Populate the new allocator functions */
	246	memcpy(&cur_alloc, &af, sizeof(cur_alloc));
f95b2888 SS	247	}
f95b2888 SS	248
e541a28d PMF	249	void *malloc(size_t size)
e541a28d PMF	250	{
1c184644 PMF	251	void *retval;
1c184644 PMF	252
8c06ba6f	253	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	254	if (cur_alloc.malloc == NULL) {
	255	lookup_all_symbols();
	256	if (cur_alloc.malloc == NULL) {
e541a28d	257	fprintf(stderr, "mallocwrap: unable to find malloc\n");
2594a5b4	258	abort();
e541a28d PMF	259	}
e541a28d PMF	260	}
2594a5b4	261	retval = cur_alloc.malloc(size);
8c06ba6f	262	if (URCU_TLS(malloc_nesting) == 1) {
6d4658aa	263	tracepoint(lttng_ust_libc, malloc,
171fcc6f	264	size, retval, LTTNG_UST_CALLER_IP());
8c06ba6f MD	265	}
8c06ba6f MD	266	URCU_TLS(malloc_nesting)--;
1c184644 PMF	267	return retval;
	268	}
	269
	270	void free(void *ptr)
	271	{
8c06ba6f	272	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	273	/*
	274	* Check whether the memory was allocated with
	275	* static_calloc_align, in which case there is nothing to free.
f95b2888	276	*/
2594a5b4 MD	277	if (caa_unlikely((char *)ptr >= static_calloc_buf &&
2594a5b4 MD	278	(char *)ptr < static_calloc_buf + STATIC_CALLOC_LEN)) {
8c06ba6f MD	279	goto end;
	280	}
	281
	282	if (URCU_TLS(malloc_nesting) == 1) {
6d4658aa	283	tracepoint(lttng_ust_libc, free,
171fcc6f	284	ptr, LTTNG_UST_CALLER_IP());
f95b2888	285	}
1c184644	286
2594a5b4 MD	287	if (cur_alloc.free == NULL) {
	288	lookup_all_symbols();
	289	if (cur_alloc.free == NULL) {
1c184644	290	fprintf(stderr, "mallocwrap: unable to find free\n");
2594a5b4	291	abort();
1c184644 PMF	292	}
1c184644 PMF	293	}
2594a5b4	294	cur_alloc.free(ptr);
8c06ba6f MD	295	end:
8c06ba6f MD	296	URCU_TLS(malloc_nesting)--;
e541a28d	297	}
f95b2888 SS	298
	299	void *calloc(size_t nmemb, size_t size)
	300	{
f95b2888 SS	301	void *retval;
f95b2888 SS	302
8c06ba6f	303	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	304	if (cur_alloc.calloc == NULL) {
	305	lookup_all_symbols();
	306	if (cur_alloc.calloc == NULL) {
f95b2888	307	fprintf(stderr, "callocwrap: unable to find calloc\n");
2594a5b4	308	abort();
f95b2888 SS	309	}
f95b2888 SS	310	}
2594a5b4	311	retval = cur_alloc.calloc(nmemb, size);
8c06ba6f	312	if (URCU_TLS(malloc_nesting) == 1) {
6d4658aa	313	tracepoint(lttng_ust_libc, calloc,
171fcc6f	314	nmemb, size, retval, LTTNG_UST_CALLER_IP());
8c06ba6f MD	315	}
8c06ba6f MD	316	URCU_TLS(malloc_nesting)--;
f95b2888 SS	317	return retval;
	318	}
	319
	320	void realloc(void ptr, size_t size)
	321	{
f95b2888 SS	322	void *retval;
f95b2888 SS	323
8c06ba6f MD	324	URCU_TLS(malloc_nesting)++;
	325	/*
	326	* Check whether the memory was allocated with
2594a5b4 MD	327	* static_calloc_align, in which case there is nothing
	328	* to free, and we need to copy the old data.
	329	*/
	330	if (caa_unlikely((char *)ptr >= static_calloc_buf &&
	331	(char *)ptr < static_calloc_buf + STATIC_CALLOC_LEN)) {
	332	size_t *old_size;
	333
	334	old_size = (size_t *) ptr - 1;
	335	if (cur_alloc.calloc == NULL) {
	336	lookup_all_symbols();
	337	if (cur_alloc.calloc == NULL) {
	338	fprintf(stderr, "reallocwrap: unable to find calloc\n");
	339	abort();
	340	}
	341	}
	342	retval = cur_alloc.calloc(1, size);
	343	if (retval) {
	344	memcpy(retval, ptr, *old_size);
	345	}
8c06ba6f MD	346	/*
	347	* Mimick that a NULL pointer has been received, so
	348	* memory allocation analysis based on the trace don't
	349	* get confused by the address from the static
	350	* allocator.
	351	*/
	352	ptr = NULL;
2594a5b4 MD	353	goto end;
	354	}
	355
	356	if (cur_alloc.realloc == NULL) {
	357	lookup_all_symbols();
	358	if (cur_alloc.realloc == NULL) {
f95b2888	359	fprintf(stderr, "reallocwrap: unable to find realloc\n");
2594a5b4	360	abort();
f95b2888 SS	361	}
f95b2888 SS	362	}
2594a5b4 MD	363	retval = cur_alloc.realloc(ptr, size);
2594a5b4 MD	364	end:
8c06ba6f	365	if (URCU_TLS(malloc_nesting) == 1) {
6d4658aa	366	tracepoint(lttng_ust_libc, realloc,
171fcc6f	367	ptr, size, retval, LTTNG_UST_CALLER_IP());
8c06ba6f MD	368	}
8c06ba6f MD	369	URCU_TLS(malloc_nesting)--;
f95b2888 SS	370	return retval;
f95b2888 SS	371	}
9d34b226 SS	372
	373	void *memalign(size_t alignment, size_t size)
	374	{
9d34b226 SS	375	void *retval;
9d34b226 SS	376
8c06ba6f	377	URCU_TLS(malloc_nesting)++;
2594a5b4 MD	378	if (cur_alloc.memalign == NULL) {
	379	lookup_all_symbols();
	380	if (cur_alloc.memalign == NULL) {
9d34b226	381	fprintf(stderr, "memalignwrap: unable to find memalign\n");
2594a5b4	382	abort();
9d34b226 SS	383	}
9d34b226 SS	384	}
2594a5b4	385	retval = cur_alloc.memalign(alignment, size);
8c06ba6f	386	if (URCU_TLS(malloc_nesting) == 1) {
6d4658aa AB	387	tracepoint(lttng_ust_libc, memalign,
6d4658aa AB	388	alignment, size, retval,
171fcc6f	389	LTTNG_UST_CALLER_IP());
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	408	if (URCU_TLS(malloc_nesting) == 1) {
6d4658aa AB	409	tracepoint(lttng_ust_libc, posix_memalign,
6d4658aa AB	410	*memptr, alignment, size,
171fcc6f	411	retval, LTTNG_UST_CALLER_IP());
8c06ba6f MD	412	}
8c06ba6f MD	413	URCU_TLS(malloc_nesting)--;
9d34b226 SS	414	return retval;
9d34b226 SS	415	}
2594a5b4	416
f4a90c3e MD	417	static
	418	void lttng_ust_fixup_malloc_nesting_tls(void)
	419	{
	420	asm volatile ("" : : "m" (URCU_TLS(malloc_nesting)));
	421	}
	422
d1f1110f	423	void lttng_ust_libc_wrapper_malloc_init(void)
2594a5b4 MD	424	{
	425	/* Initialization already done */
	426	if (cur_alloc.calloc) {
	427	return;
	428	}
f4a90c3e	429	lttng_ust_fixup_malloc_nesting_tls();
2594a5b4 MD	430	/*
	431	* Ensure the allocator is in place before the process becomes
	432	* multithreaded.
	433	*/
	434	lookup_all_symbols();
	435	}