* [libgo] Account for 32-bit fds_bits on Solaris 2
@ 2011-03-31 15:50 Rainer Orth
2011-03-31 16:05 ` Ian Lance Taylor
2011-03-31 20:53 ` Ian Lance Taylor
0 siblings, 2 replies; 8+ messages in thread
From: Rainer Orth @ 2011-03-31 15:50 UTC (permalink / raw)
To: gcc-patches; +Cc: Ian Lance Taylor
While debugging why several libgo tests on Solaris 2/SPARC were hanging
in select (cf. PR go/48242, go/48243), I found that fd_set is
typedef struct fd_set {
long fds_bits[__howmany(FD_SETSIZE, FD_NFDBITS)];
} fd_set;
The current implementation of the FD* funcs in sysfile_posix.go assumes
64-bit fds_bits. While this doesn't make a difference on little-endian
hosts, on big-endian SPARC the wrong bits are set, leading to the
observed hang since there is no activity on those random fds.
The following patch fixes this by moving the FD* implementation to two
new sysfile_fdset{32, 64}.go files to fix this. There's almost
certainly a cleaner/shorter implemenation, but this worked for me.
While the affected tests don't hang anymore now, they still don't finish
successfully, among others due to PR go/48222.
Rainer
2011-03-24 Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>
* syscalls/sysfile_posix.go (FdSet_t, FDSet, FDClr, FDIsSet)
(FDZero): Move ...
* syscalls/sysfile_fdset64.go: ... here.
New file.
* syscalls/sysfile_fdset32.go: New file.
* Makefile.am (syscall_fdset_file): Use them.
(go_syscall_files): Add $(syscall_fdset_file).
* Makefile.in: Regenerate.
diff -r e65d996c30c7 libgo/Makefile.am
--- a/libgo/Makefile.am Thu Mar 24 17:24:32 2011 +0100
+++ b/libgo/Makefile.am Thu Mar 24 20:25:57 2011 +0100
@@ -1214,6 +1214,20 @@
endif # !LIBGO_IS_SOLARIS
endif # !LIBGO_IS_LINUX
+# Define for struct fd_set.
+if LIBGO_IS_SOLARIS
+if LIBGO_IS_386
+syscall_fdset_file = syscalls/sysfile_fdset32.go
+else # !LIBGO_IS_386
+if LIBGO_IS_SPARC
+syscall_fdset_file = syscalls/sysfile_fdset32.go
+else # !LIBGO_IS_386 && !LIBGO_IS_SPARC
+syscall_fdset_file = syscalls/sysfile_fdset64.go
+endif # !LIBGO_IS_386 && !LIBGO_IS_SPARC
+endif # !LIBGO_IS_386 && !LIBGO_IS_SPARC
+else # !LIBGO_IS_SOLARIS
+syscall_fdset_file = syscalls/sysfile_fdset64.go
+endif # !LIBGO_IS_SOLARIS
# Define ForkExec, PtraceForkExec, Exec, and Waitpid.
if LIBGO_IS_RTEMS
@@ -1307,6 +1321,7 @@
syscalls/syscall_$(GOOS).go \
$(GO_SYSCALLS_SYSCALL_OS_ARCH_FILE) \
syscalls/sysfile_posix.go \
+ $(syscall_fdset_file) \
sysinfo.go \
syscall_arch.go
go_syscall_c_files = \
diff -r e65d996c30c7 libgo/syscalls/sysfile_fdset32.go
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/libgo/syscalls/sysfile_fdset32.go Thu Mar 24 20:25:57 2011 +0100
@@ -0,0 +1,35 @@
+// sysfile_fdset.go -- POSIX fd_set handling for 32-bit fds_bits.
+
+// Copyright 2010, 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Support for struct fd_set.
+
+package syscall
+
+type FdSet_t struct {
+ Fds_bits [(FD_SETSIZE + 31) / 32]int32;
+}
+
+func FDSet(fd int, set *FdSet_t) {
+ set.Fds_bits[fd / 32] |= (1 << (uint)(fd % 32))
+}
+
+func FDClr(fd int, set *FdSet_t) {
+ set.Fds_bits[fd / 32] &= ^(1 << (uint)(fd % 32))
+}
+
+func FDIsSet(fd int, set *FdSet_t) bool {
+ if set.Fds_bits[fd / 32] & (1 << (uint)(fd % 32)) != 0 {
+ return true
+ } else {
+ return false
+ }
+}
+
+func FDZero(set *FdSet_t) {
+ for i := 0; i < ((FD_SETSIZE + 63) / 32); i++ {
+ set.Fds_bits[i] = 0
+ }
+}
diff -r e65d996c30c7 libgo/syscalls/sysfile_fdset64.go
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/libgo/syscalls/sysfile_fdset64.go Thu Mar 24 20:25:57 2011 +0100
@@ -0,0 +1,35 @@
+// sysfile_fdset.go -- POSIX fd_set handling for 64-bit fds_bits.
+
+// Copyright 2010, 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Support for struct fd_set.
+
+package syscall
+
+type FdSet_t struct {
+ Fds_bits [(FD_SETSIZE + 63) / 64]int64;
+}
+
+func FDSet(fd int, set *FdSet_t) {
+ set.Fds_bits[fd / 64] |= (1 << (uint)(fd % 64))
+}
+
+func FDClr(fd int, set *FdSet_t) {
+ set.Fds_bits[fd / 64] &= ^(1 << (uint)(fd % 64))
+}
+
+func FDIsSet(fd int, set *FdSet_t) bool {
+ if set.Fds_bits[fd / 64] & (1 << (uint)(fd % 64)) != 0 {
+ return true
+ } else {
+ return false
+ }
+}
+
+func FDZero(set *FdSet_t) {
+ for i := 0; i < ((FD_SETSIZE + 63) / 64); i++ {
+ set.Fds_bits[i] = 0
+ }
+}
diff -r e65d996c30c7 libgo/syscalls/sysfile_posix.go
--- a/libgo/syscalls/sysfile_posix.go Thu Mar 24 17:24:32 2011 +0100
+++ b/libgo/syscalls/sysfile_posix.go Thu Mar 24 20:25:57 2011 +0100
@@ -181,32 +181,6 @@
return;
}
-type FdSet_t struct {
- Fds_bits [(FD_SETSIZE + 63) / 64]int64;
-}
-
-func FDSet(fd int, set *FdSet_t) {
- set.Fds_bits[fd / 64] |= (1 << (uint)(fd % 64))
-}
-
-func FDClr(fd int, set *FdSet_t) {
- set.Fds_bits[fd / 64] &= ^(1 << (uint)(fd % 64))
-}
-
-func FDIsSet(fd int, set *FdSet_t) bool {
- if set.Fds_bits[fd / 64] & (1 << (uint)(fd % 64)) != 0 {
- return true
- } else {
- return false
- }
-}
-
-func FDZero(set *FdSet_t) {
- for i := 0; i < ((FD_SETSIZE + 63) / 64); i++ {
- set.Fds_bits[i] = 0
- }
-}
-
func Select(nfds int, r *FdSet_t, w *FdSet_t, e *FdSet_t, timeout *Timeval) (n int, errno int) {
n = libc_select(nfds, (*byte)(unsafe.Pointer(r)),
(*byte)(unsafe.Pointer(e)),
--
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [libgo] Account for 32-bit fds_bits on Solaris 2
2011-03-31 15:50 [libgo] Account for 32-bit fds_bits on Solaris 2 Rainer Orth
@ 2011-03-31 16:05 ` Ian Lance Taylor
2011-03-31 16:12 ` Rainer Orth
2011-03-31 20:09 ` Richard Henderson
2011-03-31 20:53 ` Ian Lance Taylor
1 sibling, 2 replies; 8+ messages in thread
From: Ian Lance Taylor @ 2011-03-31 16:05 UTC (permalink / raw)
To: Rainer Orth; +Cc: gcc-patches
Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE> writes:
> While debugging why several libgo tests on Solaris 2/SPARC were hanging
> in select (cf. PR go/48242, go/48243), I found that fd_set is
>
> typedef struct fd_set {
> long fds_bits[__howmany(FD_SETSIZE, FD_NFDBITS)];
> } fd_set;
>
> The current implementation of the FD* funcs in sysfile_posix.go assumes
> 64-bit fds_bits. While this doesn't make a difference on little-endian
> hosts, on big-endian SPARC the wrong bits are set, leading to the
> observed hang since there is no activity on those random fds.
>
> The following patch fixes this by moving the FD* implementation to two
> new sysfile_fdset{32, 64}.go files to fix this. There's almost
> certainly a cleaner/shorter implemenation, but this worked for me.
> While the affected tests don't hang anymore now, they still don't finish
> successfully, among others due to PR go/48222.
What an annoying problem. Sorry about that. But why don't we just
change to byte?
Ian
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [libgo] Account for 32-bit fds_bits on Solaris 2
2011-03-31 16:05 ` Ian Lance Taylor
@ 2011-03-31 16:12 ` Rainer Orth
2011-03-31 20:09 ` Richard Henderson
1 sibling, 0 replies; 8+ messages in thread
From: Rainer Orth @ 2011-03-31 16:12 UTC (permalink / raw)
To: Ian Lance Taylor; +Cc: gcc-patches
Ian Lance Taylor <iant@google.com> writes:
> What an annoying problem. Sorry about that. But why don't we just
> change to byte?
If this causes the right bits to be set for big and little-endian hosts,
certainly fine with me. I haven't tried yet, but the less different
code paths, the better.
Rainer
--
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [libgo] Account for 32-bit fds_bits on Solaris 2
2011-03-31 16:05 ` Ian Lance Taylor
2011-03-31 16:12 ` Rainer Orth
@ 2011-03-31 20:09 ` Richard Henderson
2011-03-31 20:12 ` Ian Lance Taylor
1 sibling, 1 reply; 8+ messages in thread
From: Richard Henderson @ 2011-03-31 20:09 UTC (permalink / raw)
To: Ian Lance Taylor; +Cc: Rainer Orth, gcc-patches
On 03/31/2011 09:03 AM, Ian Lance Taylor wrote:
> What an annoying problem. Sorry about that. But why don't we just
> change to byte?
That would work for little-endian, but not big-endian, at least not
without even worse ugliness in two different files.
r~
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [libgo] Account for 32-bit fds_bits on Solaris 2
2011-03-31 20:09 ` Richard Henderson
@ 2011-03-31 20:12 ` Ian Lance Taylor
0 siblings, 0 replies; 8+ messages in thread
From: Ian Lance Taylor @ 2011-03-31 20:12 UTC (permalink / raw)
To: Richard Henderson; +Cc: Rainer Orth, gcc-patches
Richard Henderson <rth@redhat.com> writes:
> On 03/31/2011 09:03 AM, Ian Lance Taylor wrote:
>> What an annoying problem. Sorry about that. But why don't we just
>> change to byte?
>
> That would work for little-endian, but not big-endian, at least not
> without even worse ugliness in two different files.
Yeah, I figured that out. Different systems use different sizes for the
bitfield. Ugh.
Ian
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [libgo] Account for 32-bit fds_bits on Solaris 2
2011-03-31 15:50 [libgo] Account for 32-bit fds_bits on Solaris 2 Rainer Orth
2011-03-31 16:05 ` Ian Lance Taylor
@ 2011-03-31 20:53 ` Ian Lance Taylor
2011-04-01 7:53 ` Rainer Orth
1 sibling, 1 reply; 8+ messages in thread
From: Ian Lance Taylor @ 2011-03-31 20:53 UTC (permalink / raw)
To: Rainer Orth; +Cc: gcc-patches, gofrontend-dev
[-- Attachment #1: Type: text/plain, Size: 1160 bytes --]
Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE> writes:
> While debugging why several libgo tests on Solaris 2/SPARC were hanging
> in select (cf. PR go/48242, go/48243), I found that fd_set is
>
> typedef struct fd_set {
> long fds_bits[__howmany(FD_SETSIZE, FD_NFDBITS)];
> } fd_set;
>
> The current implementation of the FD* funcs in sysfile_posix.go assumes
> 64-bit fds_bits. While this doesn't make a difference on little-endian
> hosts, on big-endian SPARC the wrong bits are set, leading to the
> observed hang since there is no activity on those random fds.
>
> The following patch fixes this by moving the FD* implementation to two
> new sysfile_fdset{32, 64}.go files to fix this. There's almost
> certainly a cleaner/shorter implemenation, but this worked for me.
> While the affected tests don't hang anymore now, they still don't finish
> successfully, among others due to PR go/48222.
Thanks. I'm going to try gambling that every uses the type "long" for
the fds_bits array. If so, I think this patch will work. Bootstrapped
and ran Go testsuite on x86_64-unknown-linux-gnu (forcing the use of
select). Committed to mainline.
Ian
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: patch --]
[-- Type: text/x-diff, Size: 1085 bytes --]
diff -r bc59115c58cf libgo/syscalls/sysfile_posix.go
--- a/libgo/syscalls/sysfile_posix.go Thu Mar 31 09:48:32 2011 -0700
+++ b/libgo/syscalls/sysfile_posix.go Thu Mar 31 13:35:30 2011 -0700
@@ -181,20 +181,22 @@
return;
}
+const nfdbits = unsafe.Sizeof(_C_long) * 8
+
type FdSet_t struct {
- Fds_bits [(FD_SETSIZE + 63) / 64]int64;
+ Fds_bits [(FD_SETSIZE + nfdbits - 1) / nfdbits]_C_long
}
func FDSet(fd int, set *FdSet_t) {
- set.Fds_bits[fd / 64] |= (1 << (uint)(fd % 64))
+ set.Fds_bits[fd / nfdbits] |= (1 << (uint)(fd % nfdbits))
}
func FDClr(fd int, set *FdSet_t) {
- set.Fds_bits[fd / 64] &= ^(1 << (uint)(fd % 64))
+ set.Fds_bits[fd / nfdbits] &^= (1 << (uint)(fd % nfdbits))
}
func FDIsSet(fd int, set *FdSet_t) bool {
- if set.Fds_bits[fd / 64] & (1 << (uint)(fd % 64)) != 0 {
+ if set.Fds_bits[fd / nfdbits] & (1 << (uint)(fd % nfdbits)) != 0 {
return true
} else {
return false
@@ -202,7 +204,7 @@
}
func FDZero(set *FdSet_t) {
- for i := 0; i < ((FD_SETSIZE + 63) / 64); i++ {
+ for i := range set.Fds_bits {
set.Fds_bits[i] = 0
}
}
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [libgo] Account for 32-bit fds_bits on Solaris 2
2011-03-31 20:53 ` Ian Lance Taylor
@ 2011-04-01 7:53 ` Rainer Orth
2011-04-01 22:54 ` Ian Lance Taylor
0 siblings, 1 reply; 8+ messages in thread
From: Rainer Orth @ 2011-04-01 7:53 UTC (permalink / raw)
To: Ian Lance Taylor; +Cc: gcc-patches, gofrontend-dev
Ian Lance Taylor <iant@google.com> writes:
> Thanks. I'm going to try gambling that every uses the type "long" for
> the fds_bits array. If so, I think this patch will work. Bootstrapped
> and ran Go testsuite on x86_64-unknown-linux-gnu (forcing the use of
> select). Committed to mainline.
I fear you lost ;-)
* On Solaris, it's always long (i.e. either 32 or 64-bit).
* On IRIX 6.5, it's long for 32-bit and int for 64-bit (i.e. always
32-bit), while 64-bit long is 64-bit.
* On Tru64 UNIX V5.1, it's always int (i.e. 32-bit), while long is
64-bit.
This has to be system-dependent, I fear.
Rainer
--
-----------------------------------------------------------------------------
Rainer Orth, Center for Biotechnology, Bielefeld University
^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [libgo] Account for 32-bit fds_bits on Solaris 2
2011-04-01 7:53 ` Rainer Orth
@ 2011-04-01 22:54 ` Ian Lance Taylor
0 siblings, 0 replies; 8+ messages in thread
From: Ian Lance Taylor @ 2011-04-01 22:54 UTC (permalink / raw)
To: Rainer Orth; +Cc: gcc-patches, gofrontend-dev
[-- Attachment #1: Type: text/plain, Size: 931 bytes --]
Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE> writes:
> Ian Lance Taylor <iant@google.com> writes:
>
>> Thanks. I'm going to try gambling that every uses the type "long" for
>> the fds_bits array. If so, I think this patch will work. Bootstrapped
>> and ran Go testsuite on x86_64-unknown-linux-gnu (forcing the use of
>> select). Committed to mainline.
>
> I fear you lost ;-)
>
> * On Solaris, it's always long (i.e. either 32 or 64-bit).
>
> * On IRIX 6.5, it's long for 32-bit and int for 64-bit (i.e. always
> 32-bit), while 64-bit long is 64-bit.
>
> * On Tru64 UNIX V5.1, it's always int (i.e. 32-bit), while long is
> 64-bit.
>
> This has to be system-dependent, I fear.
Bother.
OK, for my next attempt I committed the appended patch, in which
mksysinfo tries to guess the right type to use. Let me know where this
fails. Bootstrapped and ran Go testsuite on x86_64-unknown-linux-gnu.
Committed to mainline.
Ian
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: patch --]
[-- Type: text/x-diff, Size: 1744 bytes --]
diff -r fa0bb5137d66 libgo/configure.ac
--- a/libgo/configure.ac Thu Mar 31 22:09:27 2011 -0700
+++ b/libgo/configure.ac Fri Apr 01 15:47:05 2011 -0700
@@ -417,7 +417,7 @@
;;
esac
-AC_CHECK_HEADERS(sys/mman.h syscall.h sys/epoll.h sys/ptrace.h sys/syscall.h sys/user.h sys/utsname.h)
+AC_CHECK_HEADERS(sys/mman.h syscall.h sys/epoll.h sys/ptrace.h sys/syscall.h sys/user.h sys/utsname.h sys/select.h)
AM_CONDITIONAL(HAVE_SYS_MMAN_H, test "$ac_cv_header_sys_mman_h" = yes)
AC_CHECK_FUNCS(srandom random strerror_r strsignal wait4)
diff -r fa0bb5137d66 libgo/mksysinfo.sh
--- a/libgo/mksysinfo.sh Thu Mar 31 22:09:27 2011 -0700
+++ b/libgo/mksysinfo.sh Fri Apr 01 15:47:05 2011 -0700
@@ -73,6 +73,9 @@
#if defined(HAVE_SYS_UTSNAME_H)
#include <sys/utsname.h>
#endif
+#if defined(HAVE_SYS_SELECT_H)
+#include <sys/select.h>
+#endif
#include <unistd.h>
EOF
@@ -438,4 +441,12 @@
-e 's/_in_addr/[4]byte/g' \
>> ${OUT}
+# Try to guess the type to use for fd_set.
+fd_set=`grep '^type _fd_set ' gen-sysinfo.go || true`
+fds_bits_type="_C_long"
+if test "$fd_set" != ""; then
+ fds_bits_type=`echo $fd_set | sed -e 's/.*[]]\([^;]*\); }$/\1/'`
+fi
+echo "type fds_bits_type $fds_bits_type" >> ${OUT}
+
exit $?
diff -r fa0bb5137d66 libgo/syscalls/sysfile_posix.go
--- a/libgo/syscalls/sysfile_posix.go Thu Mar 31 22:09:27 2011 -0700
+++ b/libgo/syscalls/sysfile_posix.go Fri Apr 01 15:47:05 2011 -0700
@@ -181,10 +181,10 @@
return;
}
-const nfdbits = unsafe.Sizeof(_C_long) * 8
+const nfdbits = unsafe.Sizeof(fds_bits_type) * 8
type FdSet_t struct {
- Fds_bits [(FD_SETSIZE + nfdbits - 1) / nfdbits]_C_long
+ Fds_bits [(FD_SETSIZE + nfdbits - 1) / nfdbits]fds_bits_type
}
func FDSet(fd int, set *FdSet_t) {
^ permalink raw reply [flat|nested] 8+ messages in thread
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Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
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2011-03-31 15:50 [libgo] Account for 32-bit fds_bits on Solaris 2 Rainer Orth
2011-03-31 16:05 ` Ian Lance Taylor
2011-03-31 16:12 ` Rainer Orth
2011-03-31 20:09 ` Richard Henderson
2011-03-31 20:12 ` Ian Lance Taylor
2011-03-31 20:53 ` Ian Lance Taylor
2011-04-01 7:53 ` Rainer Orth
2011-04-01 22:54 ` Ian Lance Taylor
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