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Re: PING: PATCH: Automatically test IFUNC implementations
On Tue, Oct 09, 2012 at 01:30:45PM -0700, Roland McGrath wrote:
> > + * Rules (tests): Filter out $(tests-ifunc) if multi-arch isn't
> > + enabled.
> > + (xtests): Filter out $(xtests-ifunc) if multi-arch isn't enabled.
> > + * include/libc-func.h: New file.
> > + * misc/libc-func.c: Likewise.
> > + * misc/Makefile (routines): Add libc-func if multi-arch is
> > + enabled.
>
> Be technically precise about conditionals:
>
> * Rules [$(multi-arch) = no] (tests): Filter out $(tests-ifunc).
>
> etc.
>
> > + * misc/Versions: Add __libc_supported_implementations to
> > + GLIBC_PRIVATE
>
> * misc/Versions (GLIBC_PRIVATE): Add __libc_supported_implementations.
>
> > + * string/test-string.h: Include <libc-func.h>.
> > + (func_list): New. Defined only if TEST_IFUNC and TEST_NAME are
> > + defined.
> > + (func_count): Likewise.
> > + (impl_count): Likewise.
> > + (impl_array): Likewise.
>
> New what?!?! And we have a convention for conditionals. Use it!
>
> [TEST_IFUNC && TEST_NAME] (func_list, func_count): New variables.
>
> etc.
>
> > +++ b/include/libc-func.h
>
> This is a pretty poor name given the function's renaming.
> Since this purely for IFUNC cases, lets have ifunc in the name.
> How about libc-ifunc-impl-list.h, struct libc_ifunc_impl, and
> __libc_ifunc_impl_list (ifunc-impl-list.c)?
>
> > +ifneq ($(multi-arch),no)
> > +routines += libc-func
> > +endif
>
> Let's just make it unconditional and let the trivial stub version be built
> when multiarch is not enabled.
>
> > +/* Default __libc_supported_implementations.
>
> /* Enumerate available IFUNC implementations of a function. Stub version.
>
> > +/* Fill ARRAY of MAX elements with IFUNC implementations for function
> > + NAME supported on target machine and return the number of valid
>
> "on this machine"
>
> This whole scheme doesn't include any way to notice which or how many
> implementations you aren't testing because your machine is incompatbile.
>
> I'm a bit inclined to make the struct include a "bool usable" field, have
> the array always filled with all function pointers, and let the testers
> skip the ones with usable==false. Then the testers can emit output saying
> "there were N variants of foo I could not test". Eventually we can feed
> this into some more full scheme to ensure that all the variants have really
> been tested well.
> > + for (impl = __start_impls; impl < __stop_impls; ++impl) \
> > + impl_count++; \
>
> A loop is a lousy way to calculate a subtraction.
>
> > +#if defined TEST_IFUNC && defined TEST_NAME
> > +# define SIZEOF_ARRAY(array) (sizeof array / sizeof array[0])
> > + func_count = __libc_supported_implementations (TEST_NAME, func_list,
> > + SIZEOF_ARRAY (func_list));
>
> Don't define a macro to use it only once.
Here is the updated patch. OK to install?
Thanks.
H.J.
---
ChangeLog | 16 +++++++++++++
Rules | 5 ++++
include/ifunc-impl-list.h | 61 +++++++++++++++++++++++++++++++++++++++++++++++
misc/Makefile | 2 +-
misc/Versions | 1 +
misc/ifunc-impl-list.c | 32 +++++++++++++++++++++++++
string/test-string.h | 58 +++++++++++++++++++++++++++++++++++++++++++-
7 files changed, 173 insertions(+), 2 deletions(-)
create mode 100644 include/ifunc-impl-list.h
create mode 100644 misc/ifunc-impl-list.c
* Rules [$(multi-arch) = no] (tests): Filter out $(tests-ifunc).
[$(multi-arch) = no] (xtests): Filter out $(xtests-ifunc).
* include/ifunc-impl-list.h: New file.
* misc/ifunc-impl-list.c: Likewise.
* misc/Makefile (routines): Add ifunc-impl-list.
* misc/Versions (GLIBC_PRIVATE): __libc_ifunc_impl_list.
* string/test-string.h: Include <ifunc-impl-list.h>.
[TEST_IFUNC && TEST_NAME] (func_list, func_count, impl_count,
impl_array): New variables.
(FOR_EACH_IMPL): Support func_list if TEST_IFUNC and TEST_NAME
are defined.
(test_init): Call __libc_ifunc_impl_list to initialize
func_list if TEST_IFUNC and TEST_NAME are defined.
diff --git a/Rules b/Rules
index 17d938e..5e33610 100644
--- a/Rules
+++ b/Rules
@@ -84,6 +84,11 @@ common-generated += dummy.o dummy.c
# This makes all the auxiliary and test programs.
.PHONY: others tests
+ifeq ($(multi-arch),no)
+tests := $(filter-out $(tests-ifunc), $(tests))
+xtests := $(filter-out $(xtests-ifunc), $(xtests))
+endif
+
ifeq ($(build-programs),yes)
others: $(addprefix $(objpfx),$(others) $(sysdep-others) $(extra-objs))
else
diff --git a/include/ifunc-impl-list.h b/include/ifunc-impl-list.h
new file mode 100644
index 0000000..36444d3
--- /dev/null
+++ b/include/ifunc-impl-list.h
@@ -0,0 +1,56 @@
+/* Internal header file for __libc_supported_implementations.
+ Copyright (C) 2012 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _IFUNC_IMPL_LIST_H
+#define _IFUNC_IMPL_LIST_H 1
+
+#include <stdbool.h>
+#include <stddef.h>
+
+struct libc_ifunc_impl
+{
+ /* The name of function to be tested. */
+ const char *name;
+ /* The address of function to be tested. */
+ void (*fn) (void);
+ /* True if this implementation is usable on this machine. */
+ bool usable;
+};
+
+/* Add an IFUNC implementation, IMPL, for function FUNC, to ARRAY with
+ USABLE at index I and advance I by one. */
+#define IFUNC_IMPL_ADD(array, i, func, usable, impl) \
+ extern __typeof (func) impl attribute_hidden; \
+ (array)[i++] = (struct libc_ifunc_impl) { #impl, (void (*) (void)) impl, (usable) };
+
+/* Return the number of IFUNC implementations, N, for function FUNC if
+ string NAME matches FUNC. */
+#define IFUNC_IMPL(n, name, func, ...) \
+ if (strcmp (name, #func) == 0) \
+ { \
+ __VA_ARGS__; \
+ return n; \
+ }
+
+/* Fill ARRAY of MAX elements with IFUNC implementations for function
+ NAME and return the number of valid entries. */
+extern size_t __libc_ifunc_impl_list (const char *name,
+ struct libc_ifunc_impl *array,
+ size_t max);
+
+#endif /* ifunc-impl-list.h */
diff --git a/misc/Makefile b/misc/Makefile
index e5e9b9f..ea68d26 100644
--- a/misc/Makefile
+++ b/misc/Makefile
@@ -65,7 +65,7 @@ routines := brk sbrk sstk ioctl \
getloadavg getclktck \
fgetxattr flistxattr fremovexattr fsetxattr getxattr \
listxattr lgetxattr llistxattr lremovexattr lsetxattr \
- removexattr setxattr getauxval
+ removexattr setxattr getauxval ifunc-impl-list
generated := tst-error1.mtrace tst-error1-mem
diff --git a/misc/Versions b/misc/Versions
index b2a9147..64632f0 100644
--- a/misc/Versions
+++ b/misc/Versions
@@ -151,5 +151,6 @@ libc {
}
GLIBC_PRIVATE {
__madvise;
+ __libc_ifunc_impl_list;
}
}
diff --git a/misc/ifunc-impl-list.c b/misc/ifunc-impl-list.c
new file mode 100644
index 0000000..c4b460d
--- /dev/null
+++ b/misc/ifunc-impl-list.c
@@ -0,0 +1,32 @@
+/* Enumerate available IFUNC implementations of a function. Stub version.
+ Copyright (C) 2012 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
+ <http://www.gnu.org/licenses/>. */
+
+#include <ifunc-impl-list.h>
+
+/* Fill ARRAY of MAX elements with IFUNC implementations for function
+ NAME supported on target machine and return the number of valid
+ entries. */
+
+size_t
+__libc_ifunc_impl_list
+ (const char *name __attribute__ ((unused)),
+ struct libc_ifunc_impl *array __attribute__ ((unused)),
+ size_t max __attribute__ ((unused)))
+{
+ return 0;
+}
diff --git a/string/test-string.h b/string/test-string.h
index c94d822..5da11fb 100644
--- a/string/test-string.h
+++ b/string/test-string.h
@@ -50,6 +50,7 @@ extern impl_t __start_impls[], __stop_impls[];
#include <error.h>
#include <errno.h>
#include <time.h>
+#include <ifunc-impl-list.h>
#define GL(x) _##x
#define GLRO(x) _##x
#include <hp-timing.h>
@@ -106,9 +107,57 @@ size_t iterations = 100000;
#define CALL(impl, ...) \
(* (proto_t) (impl)->fn) (__VA_ARGS__)
-#define FOR_EACH_IMPL(impl, notall) \
+#if defined TEST_IFUNC && defined TEST_NAME
+/* Increase size of FUNC_LIST if assert is triggered at run-time. */
+static struct libc_ifunc_impl func_list[32];
+static int func_count;
+static int impl_count = -1;
+static impl_t *impl_array;
+
+# define FOR_EACH_IMPL(impl, notall) \
+ impl_t *impl; \
+ int count; \
+ if (impl_count == -1) \
+ { \
+ impl_count = 0; \
+ if (func_count != 0) \
+ { \
+ int f; \
+ impl_t *skip = NULL, *a; \
+ for (impl = __start_impls; impl < __stop_impls; ++impl) \
+ if (strcmp (impl->name, TEST_NAME) == 0) \
+ skip = impl; \
+ else \
+ impl_count++; \
+ a = impl_array = malloc ((impl_count + func_count) * \
+ sizeof (impl_t)); \
+ for (impl = __start_impls; impl < __stop_impls; ++impl) \
+ if (impl != skip) \
+ *a++ = *impl; \
+ for (f = 0; f < func_count; f++) \
+ if (func_list[f].usable) \
+ { \
+ a->name = func_list[f].name; \
+ a->fn = func_list[f].fn; \
+ a->test = 1; \
+ a++; \
+ } \
+ impl_count = a - impl_array; \
+ } \
+ else \
+ { \
+ impl_count = __stop_impls - __start_impls; \
+ impl_array = __start_impls; \
+ } \
+ } \
+ impl = impl_array; \
+ for (count = 0; count < impl_count; ++count, ++impl) \
+ if (!notall || impl->test)
+#else
+# define FOR_EACH_IMPL(impl, notall) \
for (impl_t *impl = __start_impls; impl < __stop_impls; ++impl) \
if (!notall || impl->test)
+#endif
#define HP_TIMING_BEST(best_time, start, end) \
do \
@@ -127,6 +176,13 @@ size_t iterations = 100000;
static void
test_init (void)
{
+#if defined TEST_IFUNC && defined TEST_NAME
+# define SIZEOF_ARRAY(array) (sizeof array / sizeof array[0])
+ func_count = __libc_ifunc_impl_list (TEST_NAME, func_list,
+ (sizeof func_list
+ / sizeof func_list[0]));
+#endif
+
page_size = 2 * getpagesize ();
#ifdef MIN_PAGE_SIZE
if (page_size < MIN_PAGE_SIZE)
--
1.7.11.4