MIPS/o32: Fix internal_syscall5/6/7
Fix a commit cc25c8b4c119 ("New pthread rwlock that is more scalable.")
regression and prevent uncontrolled stack space usage from happening
when a 5-, 6- or 7-argument syscall wrapper is placed in a loop.
The cause of the problem is the use of `alloca' in regular MIPS/Linux
wrappers to force the use of the frame pointer register in any function
using one or more of these wrappers. Using the frame pointer register
is required so as not to break frame unwinding as the the stack pointer
is lowered within the inline asm used by these wrappers to make room for
the stack arguments, which 5-, 6- and 7-argument syscalls use with the
o32 ABI.
The regular MIPS/Linux wrappers are macros however, expanded inline, and
stack allocations made with `alloca' are not discarded until the return
of the function they are made in. Consequently if called in a loop,
then virtual memory is wasted, and if the loop goes through enough
iterations, then ultimately available memory can get exhausted causing
the program to crash.
Address the issue by replacing the inline code with standalone assembly
functions, which rely on the compiler arranging syscall arguments
according to the o32 function calling convention, which MIPS/Linux
syscalls also use, except for the syscall number passed and the error
flag returned. This way there is no need to fiddle with the stack
pointer anymore and all that has to be handled in the new standalone
functions is the special handling of the syscall number and the error
flag.
Redirect 5-, 6- or 7-argument MIPS16/Linux syscall wrappers to these new
functions as well, so as to avoid an unnecessary double call the
existing wrappers would cause with the new arrangement.
[BZ #21956]
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Makefile
[subdir = misc] (sysdep_routines): Remove `mips16-syscall5',
`mips16-syscall6' and `mips16-syscall7'.
(CFLAGS-mips16-syscall5.c, CFLAGS-mips16-syscall6.c)
(CFLAGS-mips16-syscall7.c): Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Versions (libc):
Remove `__mips16_syscall5', `__mips16_syscall6' and
`__mips16_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall0.c
(__mips16_syscall0): Rename `__mips16_syscall_return' to
`__mips_syscall_return'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall1.c
(__mips16_syscall1): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall2.c
(__mips16_syscall2): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall3.c
(__mips16_syscall3): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall4.c
(__mips16_syscall4): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall5.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall6.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall7.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall.h
(__mips16_syscall5): Expand to `__mips_syscall5' rather than
`__mips16_syscall5'. Remove prototype.
(__mips16_syscall6): Expand to `__mips_syscall6' rather than
`__mips16_syscall6'. Remove prototype.
(__mips16_syscall7): Expand to `__mips_syscall7' rather than
`__mips16_syscall7'. Remove prototype.
(__nomips16, __mips16_syscall_return): Move to...
* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
(__nomips16, __mips_syscall_return): ... here.
[__mips16] (INTERNAL_SYSCALL_NCS): Rename
`__mips16_syscall_return' to `__mips_syscall_return'.
[__mips16] (INTERNAL_SYSCALL_MIPS16): Pass `number' to
`internal_syscall##nr'.
[!__mips16] (INTERNAL_SYSCALL): Pass `SYS_ify (name)' to
`internal_syscall##nr'.
(FORCE_FRAME_POINTER): Remove.
(__mips_syscall5): New prototype.
(internal_syscall5): Rewrite to call `__mips_syscall5'.
(__mips_syscall6): New prototype.
(internal_syscall6): Rewrite to call `__mips_syscall6'.
(__mips_syscall7): New prototype.
(internal_syscall7): Rewrite to call `__mips_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall5.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall6.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall7.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/Makefile [subdir = misc]
(sysdep_routines): Add libc-do-syscall.
* sysdeps/unix/sysv/linux/mips/mips32/Versions (libc): Add
`__mips_syscall5', `__mips_syscall6' and `__mips_syscall7'.
2017-08-29 17:31:08 +00:00
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/* MIPS syscall wrappers.
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2024-01-01 18:12:26 +00:00
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Copyright (C) 2017-2024 Free Software Foundation, Inc.
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2013-02-27 23:45:07 +00:00
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
|
MIPS/o32: Fix internal_syscall5/6/7
Fix a commit cc25c8b4c119 ("New pthread rwlock that is more scalable.")
regression and prevent uncontrolled stack space usage from happening
when a 5-, 6- or 7-argument syscall wrapper is placed in a loop.
The cause of the problem is the use of `alloca' in regular MIPS/Linux
wrappers to force the use of the frame pointer register in any function
using one or more of these wrappers. Using the frame pointer register
is required so as not to break frame unwinding as the the stack pointer
is lowered within the inline asm used by these wrappers to make room for
the stack arguments, which 5-, 6- and 7-argument syscalls use with the
o32 ABI.
The regular MIPS/Linux wrappers are macros however, expanded inline, and
stack allocations made with `alloca' are not discarded until the return
of the function they are made in. Consequently if called in a loop,
then virtual memory is wasted, and if the loop goes through enough
iterations, then ultimately available memory can get exhausted causing
the program to crash.
Address the issue by replacing the inline code with standalone assembly
functions, which rely on the compiler arranging syscall arguments
according to the o32 function calling convention, which MIPS/Linux
syscalls also use, except for the syscall number passed and the error
flag returned. This way there is no need to fiddle with the stack
pointer anymore and all that has to be handled in the new standalone
functions is the special handling of the syscall number and the error
flag.
Redirect 5-, 6- or 7-argument MIPS16/Linux syscall wrappers to these new
functions as well, so as to avoid an unnecessary double call the
existing wrappers would cause with the new arrangement.
[BZ #21956]
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Makefile
[subdir = misc] (sysdep_routines): Remove `mips16-syscall5',
`mips16-syscall6' and `mips16-syscall7'.
(CFLAGS-mips16-syscall5.c, CFLAGS-mips16-syscall6.c)
(CFLAGS-mips16-syscall7.c): Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Versions (libc):
Remove `__mips16_syscall5', `__mips16_syscall6' and
`__mips16_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall0.c
(__mips16_syscall0): Rename `__mips16_syscall_return' to
`__mips_syscall_return'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall1.c
(__mips16_syscall1): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall2.c
(__mips16_syscall2): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall3.c
(__mips16_syscall3): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall4.c
(__mips16_syscall4): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall5.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall6.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall7.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall.h
(__mips16_syscall5): Expand to `__mips_syscall5' rather than
`__mips16_syscall5'. Remove prototype.
(__mips16_syscall6): Expand to `__mips_syscall6' rather than
`__mips16_syscall6'. Remove prototype.
(__mips16_syscall7): Expand to `__mips_syscall7' rather than
`__mips16_syscall7'. Remove prototype.
(__nomips16, __mips16_syscall_return): Move to...
* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
(__nomips16, __mips_syscall_return): ... here.
[__mips16] (INTERNAL_SYSCALL_NCS): Rename
`__mips16_syscall_return' to `__mips_syscall_return'.
[__mips16] (INTERNAL_SYSCALL_MIPS16): Pass `number' to
`internal_syscall##nr'.
[!__mips16] (INTERNAL_SYSCALL): Pass `SYS_ify (name)' to
`internal_syscall##nr'.
(FORCE_FRAME_POINTER): Remove.
(__mips_syscall5): New prototype.
(internal_syscall5): Rewrite to call `__mips_syscall5'.
(__mips_syscall6): New prototype.
(internal_syscall6): Rewrite to call `__mips_syscall6'.
(__mips_syscall7): New prototype.
(internal_syscall7): Rewrite to call `__mips_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall5.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall6.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall7.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/Makefile [subdir = misc]
(sysdep_routines): Add libc-do-syscall.
* sysdeps/unix/sysv/linux/mips/mips32/Versions (libc): Add
`__mips_syscall5', `__mips_syscall6' and `__mips_syscall7'.
2017-08-29 17:31:08 +00:00
|
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|
License along with the GNU C Library. If not, see
|
Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:
sed -ri '
s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
$(find $(git ls-files) -prune -type f \
! -name '*.po' \
! -name 'ChangeLog*' \
! -path COPYING ! -path COPYING.LIB \
! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
! -path manual/texinfo.tex ! -path scripts/config.guess \
! -path scripts/config.sub ! -path scripts/install-sh \
! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
! -path INSTALL ! -path locale/programs/charmap-kw.h \
! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
! '(' -name configure \
-execdir test -f configure.ac -o -f configure.in ';' ')' \
! '(' -name preconfigure \
-execdir test -f preconfigure.ac ';' ')' \
-print)
and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:
chmod a+x sysdeps/unix/sysv/linux/riscv/configure
# Omit irrelevant whitespace and comment-only changes,
# perhaps from a slightly-different Autoconf version.
git checkout -f \
sysdeps/csky/configure \
sysdeps/hppa/configure \
sysdeps/riscv/configure \
sysdeps/unix/sysv/linux/csky/configure
# Omit changes that caused a pre-commit check to fail like this:
# remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
git checkout -f \
sysdeps/powerpc/powerpc64/ppc-mcount.S \
sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
# Omit change that caused a pre-commit check to fail like this:
# remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 05:40:42 +00:00
|
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|
<https://www.gnu.org/licenses/>. */
|
2013-02-27 23:45:07 +00:00
|
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|
|
|
#include <sysdep.h>
|
MIPS/o32: Fix internal_syscall5/6/7
Fix a commit cc25c8b4c119 ("New pthread rwlock that is more scalable.")
regression and prevent uncontrolled stack space usage from happening
when a 5-, 6- or 7-argument syscall wrapper is placed in a loop.
The cause of the problem is the use of `alloca' in regular MIPS/Linux
wrappers to force the use of the frame pointer register in any function
using one or more of these wrappers. Using the frame pointer register
is required so as not to break frame unwinding as the the stack pointer
is lowered within the inline asm used by these wrappers to make room for
the stack arguments, which 5-, 6- and 7-argument syscalls use with the
o32 ABI.
The regular MIPS/Linux wrappers are macros however, expanded inline, and
stack allocations made with `alloca' are not discarded until the return
of the function they are made in. Consequently if called in a loop,
then virtual memory is wasted, and if the loop goes through enough
iterations, then ultimately available memory can get exhausted causing
the program to crash.
Address the issue by replacing the inline code with standalone assembly
functions, which rely on the compiler arranging syscall arguments
according to the o32 function calling convention, which MIPS/Linux
syscalls also use, except for the syscall number passed and the error
flag returned. This way there is no need to fiddle with the stack
pointer anymore and all that has to be handled in the new standalone
functions is the special handling of the syscall number and the error
flag.
Redirect 5-, 6- or 7-argument MIPS16/Linux syscall wrappers to these new
functions as well, so as to avoid an unnecessary double call the
existing wrappers would cause with the new arrangement.
[BZ #21956]
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Makefile
[subdir = misc] (sysdep_routines): Remove `mips16-syscall5',
`mips16-syscall6' and `mips16-syscall7'.
(CFLAGS-mips16-syscall5.c, CFLAGS-mips16-syscall6.c)
(CFLAGS-mips16-syscall7.c): Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Versions (libc):
Remove `__mips16_syscall5', `__mips16_syscall6' and
`__mips16_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall0.c
(__mips16_syscall0): Rename `__mips16_syscall_return' to
`__mips_syscall_return'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall1.c
(__mips16_syscall1): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall2.c
(__mips16_syscall2): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall3.c
(__mips16_syscall3): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall4.c
(__mips16_syscall4): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall5.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall6.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall7.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall.h
(__mips16_syscall5): Expand to `__mips_syscall5' rather than
`__mips16_syscall5'. Remove prototype.
(__mips16_syscall6): Expand to `__mips_syscall6' rather than
`__mips16_syscall6'. Remove prototype.
(__mips16_syscall7): Expand to `__mips_syscall7' rather than
`__mips16_syscall7'. Remove prototype.
(__nomips16, __mips16_syscall_return): Move to...
* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
(__nomips16, __mips_syscall_return): ... here.
[__mips16] (INTERNAL_SYSCALL_NCS): Rename
`__mips16_syscall_return' to `__mips_syscall_return'.
[__mips16] (INTERNAL_SYSCALL_MIPS16): Pass `number' to
`internal_syscall##nr'.
[!__mips16] (INTERNAL_SYSCALL): Pass `SYS_ify (name)' to
`internal_syscall##nr'.
(FORCE_FRAME_POINTER): Remove.
(__mips_syscall5): New prototype.
(internal_syscall5): Rewrite to call `__mips_syscall5'.
(__mips_syscall6): New prototype.
(internal_syscall6): Rewrite to call `__mips_syscall6'.
(__mips_syscall7): New prototype.
(internal_syscall7): Rewrite to call `__mips_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall5.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall6.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall7.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/Makefile [subdir = misc]
(sysdep_routines): Add libc-do-syscall.
* sysdeps/unix/sysv/linux/mips/mips32/Versions (libc): Add
`__mips_syscall5', `__mips_syscall6' and `__mips_syscall7'.
2017-08-29 17:31:08 +00:00
|
|
|
#include <sys/asm.h>
|
2013-02-27 23:45:07 +00:00
|
|
|
|
MIPS/o32: Fix internal_syscall5/6/7
Fix a commit cc25c8b4c119 ("New pthread rwlock that is more scalable.")
regression and prevent uncontrolled stack space usage from happening
when a 5-, 6- or 7-argument syscall wrapper is placed in a loop.
The cause of the problem is the use of `alloca' in regular MIPS/Linux
wrappers to force the use of the frame pointer register in any function
using one or more of these wrappers. Using the frame pointer register
is required so as not to break frame unwinding as the the stack pointer
is lowered within the inline asm used by these wrappers to make room for
the stack arguments, which 5-, 6- and 7-argument syscalls use with the
o32 ABI.
The regular MIPS/Linux wrappers are macros however, expanded inline, and
stack allocations made with `alloca' are not discarded until the return
of the function they are made in. Consequently if called in a loop,
then virtual memory is wasted, and if the loop goes through enough
iterations, then ultimately available memory can get exhausted causing
the program to crash.
Address the issue by replacing the inline code with standalone assembly
functions, which rely on the compiler arranging syscall arguments
according to the o32 function calling convention, which MIPS/Linux
syscalls also use, except for the syscall number passed and the error
flag returned. This way there is no need to fiddle with the stack
pointer anymore and all that has to be handled in the new standalone
functions is the special handling of the syscall number and the error
flag.
Redirect 5-, 6- or 7-argument MIPS16/Linux syscall wrappers to these new
functions as well, so as to avoid an unnecessary double call the
existing wrappers would cause with the new arrangement.
[BZ #21956]
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Makefile
[subdir = misc] (sysdep_routines): Remove `mips16-syscall5',
`mips16-syscall6' and `mips16-syscall7'.
(CFLAGS-mips16-syscall5.c, CFLAGS-mips16-syscall6.c)
(CFLAGS-mips16-syscall7.c): Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Versions (libc):
Remove `__mips16_syscall5', `__mips16_syscall6' and
`__mips16_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall0.c
(__mips16_syscall0): Rename `__mips16_syscall_return' to
`__mips_syscall_return'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall1.c
(__mips16_syscall1): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall2.c
(__mips16_syscall2): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall3.c
(__mips16_syscall3): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall4.c
(__mips16_syscall4): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall5.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall6.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall7.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall.h
(__mips16_syscall5): Expand to `__mips_syscall5' rather than
`__mips16_syscall5'. Remove prototype.
(__mips16_syscall6): Expand to `__mips_syscall6' rather than
`__mips16_syscall6'. Remove prototype.
(__mips16_syscall7): Expand to `__mips_syscall7' rather than
`__mips16_syscall7'. Remove prototype.
(__nomips16, __mips16_syscall_return): Move to...
* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
(__nomips16, __mips_syscall_return): ... here.
[__mips16] (INTERNAL_SYSCALL_NCS): Rename
`__mips16_syscall_return' to `__mips_syscall_return'.
[__mips16] (INTERNAL_SYSCALL_MIPS16): Pass `number' to
`internal_syscall##nr'.
[!__mips16] (INTERNAL_SYSCALL): Pass `SYS_ify (name)' to
`internal_syscall##nr'.
(FORCE_FRAME_POINTER): Remove.
(__mips_syscall5): New prototype.
(internal_syscall5): Rewrite to call `__mips_syscall5'.
(__mips_syscall6): New prototype.
(internal_syscall6): Rewrite to call `__mips_syscall6'.
(__mips_syscall7): New prototype.
(internal_syscall7): Rewrite to call `__mips_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall5.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall6.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall7.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/Makefile [subdir = misc]
(sysdep_routines): Add libc-do-syscall.
* sysdeps/unix/sysv/linux/mips/mips32/Versions (libc): Add
`__mips_syscall5', `__mips_syscall6' and `__mips_syscall7'.
2017-08-29 17:31:08 +00:00
|
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.text
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|
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|
.set nomips16
|
2013-02-27 23:45:07 +00:00
|
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2020-02-12 16:57:02 +00:00
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/* long long int __mips_syscall6 (long int arg1, long int arg2, long int arg3,
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long int arg4, long int arg5, long int arg6,
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|
long int number) */
|
MIPS/o32: Fix internal_syscall5/6/7
Fix a commit cc25c8b4c119 ("New pthread rwlock that is more scalable.")
regression and prevent uncontrolled stack space usage from happening
when a 5-, 6- or 7-argument syscall wrapper is placed in a loop.
The cause of the problem is the use of `alloca' in regular MIPS/Linux
wrappers to force the use of the frame pointer register in any function
using one or more of these wrappers. Using the frame pointer register
is required so as not to break frame unwinding as the the stack pointer
is lowered within the inline asm used by these wrappers to make room for
the stack arguments, which 5-, 6- and 7-argument syscalls use with the
o32 ABI.
The regular MIPS/Linux wrappers are macros however, expanded inline, and
stack allocations made with `alloca' are not discarded until the return
of the function they are made in. Consequently if called in a loop,
then virtual memory is wasted, and if the loop goes through enough
iterations, then ultimately available memory can get exhausted causing
the program to crash.
Address the issue by replacing the inline code with standalone assembly
functions, which rely on the compiler arranging syscall arguments
according to the o32 function calling convention, which MIPS/Linux
syscalls also use, except for the syscall number passed and the error
flag returned. This way there is no need to fiddle with the stack
pointer anymore and all that has to be handled in the new standalone
functions is the special handling of the syscall number and the error
flag.
Redirect 5-, 6- or 7-argument MIPS16/Linux syscall wrappers to these new
functions as well, so as to avoid an unnecessary double call the
existing wrappers would cause with the new arrangement.
[BZ #21956]
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Makefile
[subdir = misc] (sysdep_routines): Remove `mips16-syscall5',
`mips16-syscall6' and `mips16-syscall7'.
(CFLAGS-mips16-syscall5.c, CFLAGS-mips16-syscall6.c)
(CFLAGS-mips16-syscall7.c): Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/Versions (libc):
Remove `__mips16_syscall5', `__mips16_syscall6' and
`__mips16_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall0.c
(__mips16_syscall0): Rename `__mips16_syscall_return' to
`__mips_syscall_return'.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall1.c
(__mips16_syscall1): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall2.c
(__mips16_syscall2): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall3.c
(__mips16_syscall3): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall4.c
(__mips16_syscall4): Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall5.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall6.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall7.c:
Remove.
* sysdeps/unix/sysv/linux/mips/mips32/mips16/mips16-syscall.h
(__mips16_syscall5): Expand to `__mips_syscall5' rather than
`__mips16_syscall5'. Remove prototype.
(__mips16_syscall6): Expand to `__mips_syscall6' rather than
`__mips16_syscall6'. Remove prototype.
(__mips16_syscall7): Expand to `__mips_syscall7' rather than
`__mips16_syscall7'. Remove prototype.
(__nomips16, __mips16_syscall_return): Move to...
* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
(__nomips16, __mips_syscall_return): ... here.
[__mips16] (INTERNAL_SYSCALL_NCS): Rename
`__mips16_syscall_return' to `__mips_syscall_return'.
[__mips16] (INTERNAL_SYSCALL_MIPS16): Pass `number' to
`internal_syscall##nr'.
[!__mips16] (INTERNAL_SYSCALL): Pass `SYS_ify (name)' to
`internal_syscall##nr'.
(FORCE_FRAME_POINTER): Remove.
(__mips_syscall5): New prototype.
(internal_syscall5): Rewrite to call `__mips_syscall5'.
(__mips_syscall6): New prototype.
(internal_syscall6): Rewrite to call `__mips_syscall6'.
(__mips_syscall7): New prototype.
(internal_syscall7): Rewrite to call `__mips_syscall7'.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall5.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall6.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/mips-syscall7.S: New file.
* sysdeps/unix/sysv/linux/mips/mips32/Makefile [subdir = misc]
(sysdep_routines): Add libc-do-syscall.
* sysdeps/unix/sysv/linux/mips/mips32/Versions (libc): Add
`__mips_syscall5', `__mips_syscall6' and `__mips_syscall7'.
2017-08-29 17:31:08 +00:00
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ENTRY(__mips_syscall6)
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lw v0, 24(sp)
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syscall
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move v1, a3
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jr ra
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END(__mips_syscall6)
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libc_hidden_def (__mips_syscall6)
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