Add a generic malloc test for MALLOC_ALIGNMENT
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Commit Message
On Thu, Jul 8, 2021 at 6:46 PM Siddhesh Poyarekar <siddhesh@gotplt.org> wrote:
>
> On 7/9/21 5:36 AM, H.J. Lu wrote:
> >> It also caused:
> >>
> >> https://sourceware.org/bugzilla/show_bug.cgi?id=28068
> >>
> >> on x32.
> >
> > mcheck.c doesn't take MALLOC_ALIGNMENT into account. Will it be removed
> > or fixed?
>
> Very interesting, I think it's best to exclude the test for mcheck on
> x32 for now. I'll fix mcheck once the malloc hooks patchset[1] is in.
>
> On a separate note, this test probably deserves to be run on all
> architectures for MALLOC_ALIGNMENT.
>
> Siddhesh
Like this?
--
H.J.
Comments
> diff --git a/malloc/Makefile b/malloc/Makefile
> index 37a9a4efab..b685ed6d61 100644
> --- a/malloc/Makefile
> +++ b/malloc/Makefile
> @@ -42,6 +42,7 @@ tests := mallocbug tst-malloc tst-valloc tst-calloc tst-obstack \
> tst-malloc-stats-cancellation \
> tst-tcfree1 tst-tcfree2 tst-tcfree3 \
> tst-safe-linking \
> + tst-mallocalign1 \
>
Please remove the trailing '\'. OK otherwise.
Thanks,
Siddhesh
From dfe77e157c8edc48a27b7c72c880b2a0d8a9859a Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 8 Jul 2021 20:48:14 -0700
Subject: [PATCH] Add a generic malloc test for MALLOC_ALIGNMENT
1. Add sysdeps/generic/malloc-size.h to define size related macros for
malloc.
2. Move x86_64/tst-mallocalign1.c malloc and replace ALIGN_MASK with
MALLOC_ALIGN_MASK.
---
malloc/Makefile | 1 +
malloc/malloc-internal.h | 41 +-----------
{sysdeps/x86_64 => malloc}/tst-mallocalign1.c | 28 ++++----
sysdeps/generic/malloc-machine.h | 1 -
sysdeps/generic/malloc-size.h | 65 +++++++++++++++++++
sysdeps/x86_64/Makefile | 4 --
6 files changed, 80 insertions(+), 60 deletions(-)
rename {sysdeps/x86_64 => malloc}/tst-mallocalign1.c (69%)
create mode 100644 sysdeps/generic/malloc-size.h
@@ -42,6 +42,7 @@ tests := mallocbug tst-malloc tst-valloc tst-calloc tst-obstack \
tst-malloc-stats-cancellation \
tst-tcfree1 tst-tcfree2 tst-tcfree3 \
tst-safe-linking \
+ tst-mallocalign1 \
tests-static := \
tst-interpose-static-nothread \
@@ -21,46 +21,7 @@
#include <malloc-machine.h>
#include <malloc-sysdep.h>
-
-/* INTERNAL_SIZE_T is the word-size used for internal bookkeeping of
- chunk sizes.
-
- The default version is the same as size_t.
-
- While not strictly necessary, it is best to define this as an
- unsigned type, even if size_t is a signed type. This may avoid some
- artificial size limitations on some systems.
-
- On a 64-bit machine, you may be able to reduce malloc overhead by
- defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' at the
- expense of not being able to handle more than 2^32 of malloced
- space. If this limitation is acceptable, you are encouraged to set
- this unless you are on a platform requiring 16byte alignments. In
- this case the alignment requirements turn out to negate any
- potential advantages of decreasing size_t word size.
-
- Implementors: Beware of the possible combinations of:
- - INTERNAL_SIZE_T might be signed or unsigned, might be 32 or 64 bits,
- and might be the same width as int or as long
- - size_t might have different width and signedness as INTERNAL_SIZE_T
- - int and long might be 32 or 64 bits, and might be the same width
-
- To deal with this, most comparisons and difference computations
- among INTERNAL_SIZE_Ts should cast them to unsigned long, being
- aware of the fact that casting an unsigned int to a wider long does
- not sign-extend. (This also makes checking for negative numbers
- awkward.) Some of these casts result in harmless compiler warnings
- on some systems. */
-#ifndef INTERNAL_SIZE_T
-# define INTERNAL_SIZE_T size_t
-#endif
-
-/* The corresponding word size. */
-#define SIZE_SZ (sizeof (INTERNAL_SIZE_T))
-
-/* The corresponding bit mask value. */
-#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1)
-
+#include <malloc-size.h>
/* Called in the parent process before a fork. */
void __malloc_fork_lock_parent (void) attribute_hidden;
similarity index 69%
rename from sysdeps/x86_64/tst-mallocalign1.c
rename to malloc/tst-mallocalign1.c
@@ -17,17 +17,16 @@
#include <stdio.h>
#include <stdlib.h>
+#include <inttypes.h>
+#include <malloc-size.h>
-/* Specified by x86-64 psABI. */
-#define ALIGN_MASK (16 - 1)
-
-void *
+static void *
test (size_t s)
{
void *p = malloc (s);
- printf ("malloc: %ld, %p: %ld\n", (unsigned long) s, p,
- ((unsigned long) p) & ALIGN_MASK);
+ printf ("malloc: %zu, %p: %zu\n", s, p,
+ ((uintptr_t) p) & MALLOC_ALIGN_MASK);
return p;
}
@@ -38,35 +37,34 @@ do_test (void)
int ret = 0;
p = test (2);
- ret |= (unsigned long) p & ALIGN_MASK;
+ ret |= (uintptr_t) p & MALLOC_ALIGN_MASK;
free (p);
p = test (8);
- ret |= (unsigned long) p & ALIGN_MASK;
+ ret |= (uintptr_t) p & MALLOC_ALIGN_MASK;
free (p);
p = test (13);
- ret |= (unsigned long) p & ALIGN_MASK;
+ ret |= (uintptr_t) p & MALLOC_ALIGN_MASK;
free (p);
p = test (16);
- ret |= (unsigned long) p & ALIGN_MASK;
+ ret |= (uintptr_t) p & MALLOC_ALIGN_MASK;
free (p);
p = test (23);
- ret |= (unsigned long) p & ALIGN_MASK;
+ ret |= (uintptr_t) p & MALLOC_ALIGN_MASK;
free (p);
p = test (43);
- ret |= (unsigned long) p & ALIGN_MASK;
+ ret |= (uintptr_t) p & MALLOC_ALIGN_MASK;
free (p);
p = test (123);
- ret |= (unsigned long) p & ALIGN_MASK;
+ ret |= (uintptr_t) p & MALLOC_ALIGN_MASK;
free (p);
return ret;
}
-#define TEST_FUNCTION do_test ()
-#include "../test-skeleton.c"
+#include <support/test-driver.c>
@@ -21,7 +21,6 @@
#define _GENERIC_MALLOC_MACHINE_H
#include <atomic.h>
-#include <malloc-alignment.h>
#ifndef atomic_full_barrier
# define atomic_full_barrier() __asm ("" ::: "memory")
new file mode 100644
@@ -0,0 +1,65 @@
+/* Define INTERNAL_SIZE_T, SIZE_SZ, MALLOC_ALIGNMENT and MALLOC_ALIGN_MASK
+ for malloc.
+ Copyright (C) 2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C 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.
+
+ The GNU C 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 the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _GENERIC_MALLOC_SIZE_H
+#define _GENERIC_MALLOC_SIZE_H
+
+#include <malloc-alignment.h>
+
+/* INTERNAL_SIZE_T is the word-size used for internal bookkeeping of
+ chunk sizes.
+
+ The default version is the same as size_t.
+
+ While not strictly necessary, it is best to define this as an
+ unsigned type, even if size_t is a signed type. This may avoid some
+ artificial size limitations on some systems.
+
+ On a 64-bit machine, you may be able to reduce malloc overhead by
+ defining INTERNAL_SIZE_T to be a 32 bit `unsigned int' at the
+ expense of not being able to handle more than 2^32 of malloced
+ space. If this limitation is acceptable, you are encouraged to set
+ this unless you are on a platform requiring 16byte alignments. In
+ this case the alignment requirements turn out to negate any
+ potential advantages of decreasing size_t word size.
+
+ Implementors: Beware of the possible combinations of:
+ - INTERNAL_SIZE_T might be signed or unsigned, might be 32 or 64 bits,
+ and might be the same width as int or as long
+ - size_t might have different width and signedness as INTERNAL_SIZE_T
+ - int and long might be 32 or 64 bits, and might be the same width
+
+ To deal with this, most comparisons and difference computations
+ among INTERNAL_SIZE_Ts should cast them to unsigned long, being
+ aware of the fact that casting an unsigned int to a wider long does
+ not sign-extend. (This also makes checking for negative numbers
+ awkward.) Some of these casts result in harmless compiler warnings
+ on some systems. */
+#ifndef INTERNAL_SIZE_T
+# define INTERNAL_SIZE_T size_t
+#endif
+
+/* The corresponding word size. */
+#define SIZE_SZ (sizeof (INTERNAL_SIZE_T))
+
+/* The corresponding bit mask value. */
+#define MALLOC_ALIGN_MASK (MALLOC_ALIGNMENT - 1)
+
+
+#endif /* _GENERIC_MALLOC_SIZE_H */
@@ -13,10 +13,6 @@ sysdep_routines += _mcount
sysdep_noprof += _mcount
endif
-ifeq ($(subdir),malloc)
-tests += tst-mallocalign1
-endif
-
ifeq ($(subdir),string)
sysdep_routines += strcasecmp_l-nonascii strncase_l-nonascii
gen-as-const-headers += locale-defines.sym
--
2.31.1