[PATCH] cancellation support for linux-mips

Guido Guenther agx@sigxcpu.org
Mon Jan 20 04:57:00 GMT 2003


Hi,
attached is a first version of cancelation support for linux mips. glibc
passes make check with one additional error:

 make[2]: *** [/var/scratch/glibc/linuxthreads/tst-cancel-wrappers.out] Error 1
in /var/scratch/glibc//libc_pic.a(pread.os) pread's cancellation missing
in /var/scratch/glibc//libc_pic.a(pwrite.os) pwrite's cancellation missing
in /var/scratch/glibc//libc_pic.a(pread64.os) pread64's cancellation missing
in /var/scratch/glibc//libc_pic.a(pwrite64.os) pwrite64's cancellation missing

...but I think this is to be expected since I didn't bother to change
these s/u/s/l/mips/p{read,write}{,64}.c files yet. 
I had to remove the setting of the global errno in
sysdeps/unix/mips/sysdep.S for the _LIBC_REENTRANT case in order to
avoid an undefined reference - this doesn't seem to cause any visible
problems for linux-mips but I'm not sure about other mips ports (is this
o.k. to do? Shall I better move a copy of this file to
sysdeps/unix/sysv/linux/mips?). Comments welcome.
 -- Guido
-------------- next part --------------
--- /dev/null	Sat Mar 16 18:32:44 2002
+++ linuxthreads/sysdeps/unix/sysv/linux/mips/sysdep-cancel.h	Sun Jan 19 17:12:45 2003
@@ -0,0 +1,135 @@
+/* Copyright (C) 2003 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Guido Guenther <agx@sigxcpu.org>, 2003.
+
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <sysdep.h>
+#ifndef __ASSEMBLER__
+# include <linuxthreads/internals.h>
+#endif
+
+#if !defined NOT_IN_libc || defined IS_IN_libpthread
+
+#ifdef __PIC__
+# undef PSEUDO
+# define PSEUDO(name, syscall_name, args)				      \
+  .align 2;								      \
+  99: la t9,__syscall_error;						      \
+  jr t9;								      \
+  ENTRY (name)								      \
+    .set noreorder;							      \
+    .cpload t9;								      \
+    .set reorder;							      \
+    SINGLE_THREAD_P(t0);						      \
+    bne zero, t0, Lpseudo_cancel;					      \
+    .set noreorder;							      \
+    li v0, SYS_ify(syscall_name);					      \
+    syscall;								      \
+    .set reorder;							      \
+    bne a3, zero, SYSCALL_ERROR_LABEL;			       		      \
+    ret;								      \
+  Lpseudo_cancel:							      \
+    SAVESTK;							              \
+    sw ra, 28(sp);							      \
+    sw gp, 32(sp);							      \
+    PUSHARGS_##args;			/* save syscall args */	      	      \
+    CENABLE;								      \
+    lw gp, 32(sp);							      \
+    sw v0, 44(sp);			/* save mask */			      \
+    POPARGS_##args;			/* restore syscall args */	      \
+    .set noreorder;							      \
+    li v0, SYS_ify (syscall_name);				      	      \
+    syscall;								      \
+    .set reorder;							      \
+    sw v0, 36(sp);			/* save syscall result */             \
+    sw a3, 40(sp);			/* save syscall error flag */	      \
+    lw a0, 44(sp);			/* pass mask as arg0 */		      \
+    CDISABLE;								      \
+    lw gp, 32(sp);							      \
+    lw v0, 36(sp);			/* restore syscall result */          \
+    lw a3, 40(sp);			/* restore syscall error flag */      \
+    lw ra, 28(sp);			/* restore return address */	      \
+    RESTORESTK;							              \
+    bne a3, zero, SYSCALL_ERROR_LABEL;					      \
+  Lpseudo_end:
+#endif
+
+/* -------- sp_old
+44 _ mask _
+40 _ a3_s _
+36 _ v0_s _
+32 _  gp  _
+28 _  ra  _
+24 _ arg6 _
+20 _ arg5 _
+16 _ arg4 _
+12 _ arg3 _
+ 8 _ arg2 _
+ 4 _ arg1 _
+ 0 _ arg0 _
+   -------- sp */
+
+# define PUSHARGS_0	/* nothing to do */
+# define PUSHARGS_1	PUSHARGS_0 sw a0, 0(sp);
+# define PUSHARGS_2	PUSHARGS_1 sw a1, 4(sp);
+# define PUSHARGS_3	PUSHARGS_2 sw a2, 8(sp);
+# define PUSHARGS_4	PUSHARGS_3 sw a3, 12(sp);
+# define PUSHARGS_5	PUSHARGS_4 lw t0, 64(sp); sw t0, 16(sp);
+# define PUSHARGS_6	PUSHARGS_5 lw t1, 68(sp); sw t1, 20(sp);
+# define PUSHARGS_7	PUSHARGS_6 lw t2, 72(sp); sw,t2, 24(sp);
+
+# define POPARGS_0	/* nothing to do */
+# define POPARGS_1	POPARGS_0 lw a0, 0(sp);
+# define POPARGS_2	POPARGS_1 lw a1, 4(sp);
+# define POPARGS_3	POPARGS_2 lw a2, 8(sp);
+# define POPARGS_4	POPARGS_3 lw a3, 12(sp);
+# define POPARGS_5	POPARGS_4 /* args already in new stackframe */
+# define POPARGS_6	POPARGS_5
+# define POPARGS_7	POPARGS_6
+
+# define SAVESTK 	subu sp, 48
+# define RESTORESTK 	addu sp, 48
+
+# ifdef IS_IN_libpthread
+#  define CENABLE	la t9, __pthread_enable_asynccancel; jalr t9;
+#  define CDISABLE	la t9, __pthread_disable_asynccancel; jalr t9;
+#  define __local_multiple_threads __pthread_multiple_threads
+# else
+#  define CENABLE	la t9, __libc_enable_asynccancel; jalr t9;
+#  define CDISABLE	la t9, __libc_disable_asynccancel; jalr t9;
+#  define __local_multiple_threads __libc_multiple_threads
+# endif
+
+# if !defined NOT_IN_libc
+#  define __local_multiple_threads __libc_multiple_threads
+# else
+#  define __local_multiple_threads __pthread_multiple_threads
+# endif
+
+# ifndef __ASSEMBLER__
+extern int __local_multiple_threads attribute_hidden;
+#  define SINGLE_THREAD_P __builtin_expect (__local_multiple_threads == 0, 1)
+# else
+#  define SINGLE_THREAD_P(reg) lw reg, __local_multiple_threads
+#endif
+
+#elif !defined __ASSEMBLER__
+
+/* This code should never be used but we define it anyhow.  */
+# define SINGLE_THREAD_P (1)
+
+#endif
--- /dev/null	Sat Mar 16 18:32:44 2002
+++ linuxthreads/sysdeps/unix/sysv/linux/mips/Makefile	Thu Jan  9 16:12:16 2003
@@ -0,0 +1,2 @@
+# pull in __syscall_error routine
+libpthread-routines += sysdep
Index: sysdeps/unix/mips/sysdep.S
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/unix/mips/sysdep.S,v
retrieving revision 1.12
diff -u -u -r1.12 sysdep.S
--- sysdeps/unix/mips/sysdep.S	6 Jul 2001 04:56:11 -0000	1.12
+++ sysdeps/unix/mips/sysdep.S	20 Jan 2003 01:01:27 -0000
@@ -51,9 +56,6 @@
 	li	v0, EAGAIN
 skip:
 #endif
-	/* Store it in the "real" variable ... */
-	sw v0, errno
-
 	/* Find our per-thread errno address  */
 	jal	__errno_location
 
Index: sysdeps/unix/sysv/linux/mips/sysdep.h
===================================================================
RCS file: /cvs/glibc/libc/sysdeps/unix/sysv/linux/mips/sysdep.h,v
retrieving revision 1.3
diff -u -r1.3 sysdep.h
--- sysdeps/unix/sysv/linux/mips/sysdep.h	15 Jan 2003 01:02:03 -0000	1.3
+++ sysdeps/unix/sysv/linux/mips/sysdep.h	20 Jan 2003 01:19:54 -0000
@@ -33,7 +33,15 @@
 # define SYS_ify(syscall_name)	__NR_/**/syscall_name
 #endif
 
-#ifndef __ASSEMBLER__
+#ifdef __ASSEMBLER__
+
+/* We don't want the label for the error handler to be visible in the symbol
+   table when we define it here.  */
+#ifdef __PIC__
+# define SYSCALL_ERROR_LABEL 99b
+#endif
+
+#else   /* ! __ASSEMBLER__ */
 
 /* Define a macro which expands into the inline wrapper code for a system
    call.  */
@@ -269,6 +277,6 @@
 
 #define __SYSCALL_CLOBBERS "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24", "$25"
 
-#endif /* __ASSEMBLER__ */
+#endif /* ! __ASSEMBLER__ */
 
 #endif /* linux/mips/sysdep.h */


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