* configure.ac: Add check for fallocate.
	* configure: Regenerate.
	* config.in: Regenerate.

	* options.h (class General_options): Add --mmap-output-file and
	--posix-fallocate options.
	* output.cc: (posix_fallocate): Remove; replace with...
	(gold_fallocate): New function.
	(Output_file::map_no_anonymous): Call gold_fallocate.
	(Output_file::map): Check --mmap-output-file option.
This commit is contained in:
Cary Coutant 2012-06-06 22:12:47 +00:00
parent 8fe6640e15
commit 7c0640fa36
6 changed files with 52 additions and 18 deletions

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@ -1,3 +1,16 @@
2012-06-06 Cary Coutant <ccoutant@google.com>
* configure.ac: Add check for fallocate.
* configure: Regenerate.
* config.in: Regenerate.
* options.h (class General_options): Add --mmap-output-file and
--posix-fallocate options.
* output.cc: (posix_fallocate): Remove; replace with...
(gold_fallocate): New function.
(Output_file::map_no_anonymous): Call gold_fallocate.
(Output_file::map): Check --mmap-output-file option.
2012-06-05 Jing Yu <jingyu@google.com>
* gold.h (textdomain): Add do {} to empty while(0).

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@ -79,6 +79,9 @@
/* Define to 1 if you have the <ext/hash_set> header file. */
#undef HAVE_EXT_HASH_SET
/* Define to 1 if you have the `fallocate' function. */
#undef HAVE_FALLOCATE
/* Define to 1 if you have the `ffsll' function. */
#undef HAVE_FFSLL

3
gold/configure vendored
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@ -3222,6 +3222,7 @@ am__tar='${AMTAR} chof - "$$tardir"'; am__untar='${AMTAR} xf -'
ac_config_headers="$ac_config_headers config.h:config.in"
# PR 14072
@ -7123,7 +7124,7 @@ fi
done
for ac_func in mallinfo posix_fallocate readv sysconf times
for ac_func in mallinfo posix_fallocate fallocate readv sysconf times
do :
as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
ac_fn_cxx_check_func "$LINENO" "$ac_func" "$as_ac_var"

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@ -499,7 +499,7 @@ AC_LANG_PUSH(C++)
AC_CHECK_HEADERS(tr1/unordered_set tr1/unordered_map)
AC_CHECK_HEADERS(ext/hash_map ext/hash_set)
AC_CHECK_HEADERS(byteswap.h)
AC_CHECK_FUNCS(mallinfo posix_fallocate readv sysconf times)
AC_CHECK_FUNCS(mallinfo posix_fallocate fallocate readv sysconf times)
AC_CHECK_DECLS([basename, ffs, asprintf, vasprintf, snprintf, vsnprintf, strverscmp, strndup, memmem])
# Use of ::std::tr1::unordered_map::rehash causes undefined symbols

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@ -889,6 +889,10 @@ class General_options
DEFINE_string(m, options::EXACTLY_ONE_DASH, 'm', "",
N_("Set GNU linker emulation; obsolete"), N_("EMULATION"));
DEFINE_bool(mmap_output_file, options::TWO_DASHES, '\0', true,
N_("Map the output file for writing (default)."),
N_("Do not map the output file for writing."));
DEFINE_bool(print_map, options::TWO_DASHES, 'M', false,
N_("Write map file on standard output"), NULL);
DEFINE_string(Map, options::ONE_DASH, '\0', NULL, N_("Write map file"),
@ -939,6 +943,11 @@ class General_options
N_("Pass an option to the plugin"), N_("OPTION"));
#endif
DEFINE_bool(posix_fallocate, options::TWO_DASHES, '\0', true,
N_("Use posix_fallocate to reserve space in the output file"
" (default)."),
N_("Use fallocate or ftruncate to reserve space."));
DEFINE_bool(preread_archive_symbols, options::TWO_DASHES, '\0', false,
N_("Preread archive symbols when multi-threaded"), NULL);

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@ -111,20 +111,6 @@ extern "C" void *gold_mremap(void *, size_t, size_t, int);
# define MREMAP_MAYMOVE 1
#endif
#ifndef HAVE_POSIX_FALLOCATE
// A dummy, non general, version of posix_fallocate. Here we just set
// the file size and hope that there is enough disk space. FIXME: We
// could allocate disk space by walking block by block and writing a
// zero byte into each block.
static int
posix_fallocate(int o, off_t offset, off_t len)
{
if (ftruncate(o, offset + len) < 0)
return errno;
return 0;
}
#endif // !defined(HAVE_POSIX_FALLOCATE)
// Mingw does not have S_ISLNK.
#ifndef S_ISLNK
# define S_ISLNK(mode) 0
@ -133,6 +119,27 @@ posix_fallocate(int o, off_t offset, off_t len)
namespace gold
{
// A wrapper around posix_fallocate. If we don't have posix_fallocate,
// or the --no-posix-fallocate option is set, we try the fallocate
// system call directly. If that fails, we use ftruncate to set
// the file size and hope that there is enough disk space.
static int
gold_fallocate(int o, off_t offset, off_t len)
{
#ifdef HAVE_POSIX_FALLOCATE
if (parameters->options().posix_fallocate())
return ::posix_fallocate(o, offset, len);
#endif // defined(HAVE_POSIX_FALLOCATE)
#ifdef HAVE_FALLOCATE
if (::fallocate(o, 0, offset, len) == 0)
return 0;
#endif // defined(HAVE_FALLOCATE)
if (::ftruncate(o, offset + len) < 0)
return errno;
return 0;
}
// Output_data variables.
bool Output_data::allocated_sizes_are_fixed;
@ -5014,7 +5021,7 @@ Output_file::map_no_anonymous(bool writable)
// but that would be a more significant performance hit.
if (writable)
{
int err = ::posix_fallocate(o, 0, this->file_size_);
int err = gold_fallocate(o, 0, this->file_size_);
if (err != 0)
gold_fatal(_("%s: %s"), this->name_, strerror(err));
}
@ -5041,7 +5048,8 @@ Output_file::map_no_anonymous(bool writable)
void
Output_file::map()
{
if (this->map_no_anonymous(true))
if (parameters->options().mmap_output_file()
&& this->map_no_anonymous(true))
return;
// The mmap call might fail because of file system issues: the file