From 2bf45345dbb001c5cb1e808a007ad08d54dfff58 Mon Sep 17 00:00:00 2001 From: jruoho Date: Wed, 7 Jul 2010 11:04:52 +0000 Subject: [PATCH] Move the thread stack attribute functions to a separate page. In addition, document pthread_attr_getstack() and pthread_attr_setstack(). Try to also document these a little better (in particular, note some items in the long list of caveats and questions related to application-controlled thread stack). --- distrib/sets/lists/comp/mi | 8 +- lib/libpthread/Makefile | 12 +- lib/libpthread/pthread_attr.3 | 29 +--- lib/libpthread/pthread_attr_getstack.3 | 177 +++++++++++++++++++++++++ 4 files changed, 193 insertions(+), 33 deletions(-) create mode 100644 lib/libpthread/pthread_attr_getstack.3 diff --git a/distrib/sets/lists/comp/mi b/distrib/sets/lists/comp/mi index 4ecce734422b..21045bb3ee3c 100644 --- a/distrib/sets/lists/comp/mi +++ b/distrib/sets/lists/comp/mi @@ -1,4 +1,4 @@ -# $NetBSD: mi,v 1.1479 2010/07/06 21:36:34 jruoho Exp $ +# $NetBSD: mi,v 1.1480 2010/07/07 11:04:52 jruoho Exp $ # # Note: don't delete entries from here - mark them as "obsolete" instead. # @@ -7571,6 +7571,7 @@ ./usr/share/man/cat3/pthread_attr_getschedparam.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_getschedpolicy.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_getscope.0 comp-c-catman .cat +./usr/share/man/cat3/pthread_attr_getstack.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_getstackaddr.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_getstacksize.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_init.0 comp-c-catman .cat @@ -7582,6 +7583,7 @@ ./usr/share/man/cat3/pthread_attr_setschedparam.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_setschedpolicy.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_setscope.0 comp-c-catman .cat +./usr/share/man/cat3/pthread_attr_setstack.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_setstackaddr.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_attr_setstacksize.0 comp-c-catman .cat ./usr/share/man/cat3/pthread_barierattr_destroy.0 comp-obsolete obsolete @@ -13409,6 +13411,7 @@ ./usr/share/man/html3/pthread_attr_getschedparam.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_getschedpolicy.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_getscope.html comp-c-htmlman html +./usr/share/man/html3/pthread_attr_getstack.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_getstackaddr.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_getstacksize.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_init.html comp-c-htmlman html @@ -13420,6 +13423,7 @@ ./usr/share/man/html3/pthread_attr_setschedparam.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_setschedpolicy.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_setscope.html comp-c-htmlman html +./usr/share/man/html3/pthread_attr_setstack.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_setstackaddr.html comp-c-htmlman html ./usr/share/man/html3/pthread_attr_setstacksize.html comp-c-htmlman html ./usr/share/man/html3/pthread_barrier_destroy.html comp-c-htmlman html @@ -19241,6 +19245,7 @@ ./usr/share/man/man3/pthread_attr_getschedparam.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_getschedpolicy.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_getscope.3 comp-c-man .man +./usr/share/man/man3/pthread_attr_getstack.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_getstackaddr.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_getstacksize.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_init.3 comp-c-man .man @@ -19252,6 +19257,7 @@ ./usr/share/man/man3/pthread_attr_setschedparam.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_setschedpolicy.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_setscope.3 comp-c-man .man +./usr/share/man/man3/pthread_attr_setstack.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_setstackaddr.3 comp-c-man .man ./usr/share/man/man3/pthread_attr_setstacksize.3 comp-c-man .man ./usr/share/man/man3/pthread_barierattr_destroy.3 comp-obsolete obsolete diff --git a/lib/libpthread/Makefile b/lib/libpthread/Makefile index 7c778797c44f..263f4cd03177 100644 --- a/lib/libpthread/Makefile +++ b/lib/libpthread/Makefile @@ -1,4 +1,4 @@ -# $NetBSD: Makefile,v 1.60 2010/07/07 08:57:36 jruoho Exp $ +# $NetBSD: Makefile,v 1.61 2010/07/07 11:04:54 jruoho Exp $ # WARNS= 4 @@ -93,6 +93,7 @@ MAN+= affinity.3 pthread.3 \ pthread_attr_getdetachstate.3 \ pthread_attr_getname_np.3 \ pthread_attr_getscope.3 \ + pthread_attr_getstack.3 \ pthread_attr_setcreatesuspend_np.3 \ pthread_attr_setname_np.3 \ pthread_barrier_destroy.3 pthread_barrier_init.3 \ @@ -121,12 +122,8 @@ MLINKS+= affinity.3 pthread_getaffinity_np.3 MLINKS+= pthread_attr.3 pthread_attr_init.3 MLINKS+= pthread_attr.3 pthread_attr_destroy.3 -MLINKS+= pthread_attr.3 pthread_attr_setstacksize.3 -MLINKS+= pthread_attr.3 pthread_attr_getstacksize.3 MLINKS+= pthread_attr.3 pthread_attr_setguardsize.3 MLINKS+= pthread_attr.3 pthread_attr_getguardsize.3 -MLINKS+= pthread_attr.3 pthread_attr_setstackaddr.3 -MLINKS+= pthread_attr.3 pthread_attr_getstackaddr.3 MLINKS+= pthread_attr.3 pthread_attr_setinheritsched.3 MLINKS+= pthread_attr.3 pthread_attr_getinheritsched.3 MLINKS+= pthread_attr.3 pthread_attr_setschedparam.3 @@ -136,6 +133,11 @@ MLINKS+= pthread_attr.3 pthread_attr_getschedpolicy.3 MLINKS+= pthread_attr_getdetachstate.3 pthread_attr_setdetachstate.3 MLINKS+= pthread_attr_getscope.3 pthread_attr_setscope.3 +MLINKS+= pthread_attr_getstack.3 pthread_attr_setstack.3 \ + pthread_attr_getstack.3 pthread_attr_getstacksize.3 \ + pthread_attr_getstack.3 pthread_attr_setstacksize.3 \ + pthread_attr_getstack.3 pthread_attr_getstackaddr.3 \ + pthread_attr_getstack.3 pthread_attr_setstackaddr.3 MLINKS+= pthread_barrierattr.3 pthread_barrierattr_init.3 MLINKS+= pthread_barrierattr.3 pthread_barrierattr_destroy.3 diff --git a/lib/libpthread/pthread_attr.3 b/lib/libpthread/pthread_attr.3 index ad12c0bd68fa..98e1c6e6319e 100644 --- a/lib/libpthread/pthread_attr.3 +++ b/lib/libpthread/pthread_attr.3 @@ -1,4 +1,4 @@ -.\" $NetBSD: pthread_attr.3,v 1.13 2010/07/07 08:57:36 jruoho Exp $ +.\" $NetBSD: pthread_attr.3,v 1.14 2010/07/07 11:04:54 jruoho Exp $ .\" .\" Copyright (c) 2002 The NetBSD Foundation, Inc. .\" All rights reserved. @@ -59,12 +59,8 @@ .Sh NAME .Nm pthread_attr_init , .Nm pthread_attr_destroy , -.Nm pthread_attr_setstacksize , -.Nm pthread_attr_getstacksize , .Nm pthread_attr_setguardsize , .Nm pthread_attr_getguardsize , -.Nm pthread_attr_setstackaddr , -.Nm pthread_attr_getstackaddr , .Nm pthread_attr_setinheritsched , .Nm pthread_attr_getinheritsched , .Nm pthread_attr_setschedparam , @@ -81,18 +77,10 @@ .Ft int .Fn pthread_attr_destroy "pthread_attr_t *attr" .Ft int -.Fn pthread_attr_setstacksize "pthread_attr_t *attr" "size_t stacksize" -.Ft int -.Fn pthread_attr_getstacksize "const pthread_attr_t * restrict attr" "size_t * restrict stacksize" -.Ft int .Fn pthread_attr_setguardsize "pthread_attr_t *attr" "size_t guardsize" .Ft int .Fn pthread_attr_getguardsize "const pthread_attr_t * restrict attr" "size_t * restrict guardsize" .Ft int -.Fn pthread_attr_setstackaddr "pthread_attr_t *attr" "void *stackaddr" -.Ft int -.Fn pthread_attr_getstackaddr "const pthread_attr_t * restrict attr" "void ** restrict stackaddr" -.Ft int .Fn pthread_attr_setinheritsched "pthread_attr_t *attr" "int inheritsched" .Ft int .Fn pthread_attr_getinheritsched "const pthread_attr_t * restrict attr" "int * restrict inheritsched" @@ -150,16 +138,7 @@ The value specified by is invalid. .El .Pp -.Fn pthread_attr_setstacksize -may fail if: -.Bl -tag -width Er -.It Bq Er EINVAL -.Fa stacksize -is less than -.Dv PTHREAD_STACK_MIN . -.El -.Pp -Fn pthread_attr_setinheritsched +.Fn pthread_attr_setinheritsched may fail if: .Bl -tag -width Er .It Bq Er EINVAL @@ -196,10 +175,6 @@ Invalid or unsupported value for .Sh STANDARDS .Fn pthread_attr_init , .Fn pthread_attr_destroy , -.Fn pthread_attr_setstacksize , -.Fn pthread_attr_getstacksize , -.Fn pthread_attr_setstackaddr , -.Fn pthread_attr_getstackaddr , .Fn pthread_attr_setinheritsched , .Fn pthread_attr_getinheritsched , .Fn pthread_attr_setschedparam , diff --git a/lib/libpthread/pthread_attr_getstack.3 b/lib/libpthread/pthread_attr_getstack.3 new file mode 100644 index 000000000000..e76a89db29a6 --- /dev/null +++ b/lib/libpthread/pthread_attr_getstack.3 @@ -0,0 +1,177 @@ +.\" $NetBSD: pthread_attr_getstack.3,v 1.1 2010/07/07 11:04:54 jruoho Exp $ +.\" +.\" Copyright (c) 2010 Jukka Ruohonen +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS +.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED +.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS +.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR +.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF +.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS +.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN +.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) +.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +.\" POSSIBILITY OF SUCH DAMAGE. +.\" +.Dd July 7, 2010 +.Dt PTHREAD_ATTR_GETSTACK 3 +.Os +.Sh NAME +.Nm pthread_attr_getstack +.Nd get and set thread stack attributes +.Sh LIBRARY +.Lb libpthread +.Sh SYNOPSIS +.In pthread.h +.Ft int +.Fn pthread_attr_getstack \ +"const pthread_attr_t * restrict attr" \ +"void ** restrict stackaddr, size_t * restrict stacksize" +.Ft int +.Fn pthread_attr_setstack \ +"pthread_attr_t * restrict attr" "void *stackaddr, size_t stacksize" +.Ft int +.Fn pthread_attr_getstacksize \ +"const pthread_attr_t * restrict attr" "size_t * restrict stacksize" +.Ft int +.Fn pthread_attr_setstacksize \ +"pthread_attr_t *attr" "size_t stacksize" +.Ft int +.Fn pthread_attr_getstackaddr \ +"const pthread_attr_t * restrict attr" "void ** restrict stackaddr" +.Ft int +.Fn pthread_attr_setstackaddr \ +"pthread_attr_t *attr" "void *stackaddr" +.Sh DESCRIPTION +The +.Fn pthread_attr_getstack +and +.Fn pthread_attr_setstack +functions get and set, respectively, the thread stack attributes +.Fa stackaddr +and +.Fa stacksize +in the +.Fa attr +object. +The remaining four functions behave similarly, +but instead of getting or setting both +.Fa stackaddr +and +.Fa stacksize , +these get and set the values individually. +.Pp +The +.Fa stacksize +parameter is defined to be the minimum stack size (in bytes) +allocated for the thread's stack during the creation of the thread. +The +.Fa stackaddr +attribute specifies the location of storage to be used for the thread's stack. +All pages within the stack described by +.Fa stackaddr +and +.Fa stacksize +are both readable and writable by the thread. +.Pp +The behavior is undefined in all functions if the +.Fa attr +parameter does not refer to an attribute object initialized by using +.Xr pthread_attr_init 3 +prior to the call. +In addition, undefined behavior may follow if the +.Fn pthread_attr_getstack +function is called before the +.Fa stackaddr +attribute has been set. +.Sh RATIONALE +The rationale behind these functions is to address cases where an application +may be used in an environment where the stack of a thread must be placed to +some particular region of memory. +For the majority of applications, this is seldom necessary, +and the use of these functions should be generally avoided. +At least few potential caveats can be mentioned. +.Bl -bullet -offset 2n +.It +There is a certain degree of ambiguity in the +.Tn POSIX +standard with respect to thread stack. +.It +The exact behavior of the functions may vary +both across machines and operating systems. +In particular, the address specified by +.Fa stackaddr +should be suitably aligned. +The system page size, as specified by +.Xr sysconf 3 , +and the use of +.Xr posix_memalign 3 +may guarantee some degree of portability. +.It +If the application modifies the stack address, it claims also +the responsibility of allocating the stack area and guarding it against +possible stack overflow. +This implies that the application may need to also allocate a suitable +guard area that is protected from reading and writing. +.It +Moreoever, if +.Fa attr +is used to create multiple threads, the stack address must be changed +by the application between successive calls to +.Xr pthread_create 3 . +.El +.Sh RETURN VALUES +If successful, these functions return 0. +Otherwise, an error number is returned to indicate the error. +.Sh ERRORS +No errors are defined for the three functions that obtain the stack values. +The three functions that set the stack values may fail if: +.Bl -tag -width Er +.It Bq Er ENOMEM +There was insufficient memory to complete the operation. +.El +.Pp +The +.Fn pthread_attr_setstacksize +function may additionally fail if: +.Bl -tag -width Er +.It Bq Er EINVAL +The specified +.Fa stacksize +is less than +.Dv PTHREAD_STACK_MIN +or exceeds some system-imposed limit. +.El +.Sh SEE ALSO +.Xr pthread_attr 3 +.Sh STANDARDS +The +.Fn pthread_attr_getstack +and +.Fn pthread_attr_setstack +functions as well as +.Fn pthread_attr_getstacksize +and +.Fn pthread_attr_setstacksize +conform to +.St -p1003.1-2008 . +The +.Fn pthread_attr_getstackaddr +and +.Fn pthread_attr_setstackaddr +conform to +.St -p1003.1-2004 , +where these were marked as obsolescent due concerns about portability. +The 2008 revision removed these two functions from the specification.