X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust-libc-wrapper%2Flttng-ust-malloc.c;h=f3e1e19e28e52d8d5fe07d399f6c4741d0d87282;hb=HEAD;hp=d407985f58c9d6abd306bd32ba1d3ebddfc885be;hpb=4b4a133740c87d9a851023a7aeb06b78d887e51b;p=lttng-ust.git

diff --git a/liblttng-ust-libc-wrapper/lttng-ust-malloc.c b/liblttng-ust-libc-wrapper/lttng-ust-malloc.c
deleted file mode 100644
index d407985f..00000000
--- a/liblttng-ust-libc-wrapper/lttng-ust-malloc.c
+++ /dev/null
@@ -1,440 +0,0 @@
-/*
- * 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 <malloc.h>
-
-#include <urcu/system.h>
-#include <urcu/uatomic.h>
-#include <urcu/compiler.h>
-#include <urcu/tls-compat.h>
-#include <urcu/arch.h>
-
-#include <lttng/ust-libc-wrapper.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();
-}