Re: [Qemu-devel] [Patch] Make usermode stacksize (-s) configurable at compile-time

[Riku Voipio <riku.voipio@iki.fi>]

On Sun, Oct 25, 2009 at 06:49:44PM +0100, Jan-Simon Möller wrote:
> We encontered problems with the low default value for the stacksize in usermode (ok, whats "low"). 
> For environments like scratchbox, its hard to use "-s" as qemu is called by binfmt mechanism.
> The attached patch makes this configurable at compile-time.

fwiw in scratchbox we have a wrapper in between binfmt and qemu (called misc_runner) that sets any
necessary command line parameters for qemu. You might want to consider a similar approach so we
don't need to add a configure option (and thus hardcode the setting) to qemu for every command
line option that might need changing.

> Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
> 
> diff --git a/configure b/configure                                     
> index 43d87c5..dad9175 100755                                          
> --- a/configure                                                        
> +++ b/configure                                                        
> @@ -220,6 +220,7 @@ uname_release=""                                   
>  io_thread="no"                                                        
>  mixemu="no"                                                           
>  kerneldir=""                                                          
> +user_mode_stacksize=""                                                
>  aix="no"                                                              
>  blobs="yes"                                                           
>  pkgversion=""                                                         
> @@ -557,6 +558,8 @@ for opt do                                         
>    ;;                                                                  
>    --kerneldir=*) kerneldir="$optarg"                                  
>    ;;                                                                  
> +  --user-mode-stacksize=*) user_mode_stacksize="$optarg"              
> +  ;;                                                                  
>    --with-pkgversion=*) pkgversion=" ($optarg)"                        
>    ;;                                                                  
>    --disable-docs) docs="no"                                           
> @@ -713,6 +716,7 @@ echo "  --enable-linux-aio       enable Linux AIO support"
>  echo "  --enable-io-thread       enable IO thread"
>  echo "  --disable-blobs          disable installing provided firmware blobs"
>  echo "  --kerneldir=PATH         look for kernel includes in PATH"
> +echo "  --user-mode-stacksize=   set default stack size in bytes (as -s, only in usermode)"
>  echo ""
>  echo "NOTE: The object files are built at the place where configure is launched"
>  exit 1
> @@ -2481,6 +2485,16 @@ if test "$target_user_only" = "yes" -a "$static" = "no" -a \
>    ldflags="-pie $ldflags"
>  fi
> 
> +# change default stacksize in usermode
> +#
> +if test "$target_user_only" = "yes" -a "$user_mode_stacksize" != "" ; then
> + cflags="-DUSER_MODE_STACKSIZE=$user_mode_stacksize $cflags"
> + echo "user_mode_stack   $user_mode_stacksize"
> +else
> + echo "user_mode_stack   default"
> +fi
> +
> +
>  if test "$target_softmmu" = "yes" -a \( \
>          "$TARGET_ARCH" = "microblaze" -o \
>          "$TARGET_ARCH" = "cris" \) ; then
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 81a1ada..9ac2421 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -51,7 +51,10 @@ const char *qemu_uname_release = CONFIG_UNAME_RELEASE;
>  /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
>     we allocate a bigger stack. Need a better solution, for example
>     by remapping the process stack directly at the right place */
> -unsigned long x86_stack_size = 512 * 1024;
> +#ifndef USER_MODE_STACKSIZE
> +#define USER_MODE_STACKSIZE (512 * 1024)
> +#endif
> +unsigned long x86_stack_size = USER_MODE_STACKSIZE;
> 
>  void gemu_log(const char *fmt, ...)
>  {
> 

> diff --git a/configure b/configure
> index 43d87c5..dad9175 100755
> --- a/configure
> +++ b/configure
> @@ -220,6 +220,7 @@ uname_release=""
>  io_thread="no"
>  mixemu="no"
>  kerneldir=""
> +user_mode_stacksize=""
>  aix="no"
>  blobs="yes"
>  pkgversion=""
> @@ -557,6 +558,8 @@ for opt do
>    ;;
>    --kerneldir=*) kerneldir="$optarg"
>    ;;
> +  --user-mode-stacksize=*) user_mode_stacksize="$optarg"
> +  ;;
>    --with-pkgversion=*) pkgversion=" ($optarg)"
>    ;;
>    --disable-docs) docs="no"
> @@ -713,6 +716,7 @@ echo "  --enable-linux-aio       enable Linux AIO support"
>  echo "  --enable-io-thread       enable IO thread"
>  echo "  --disable-blobs          disable installing provided firmware blobs"
>  echo "  --kerneldir=PATH         look for kernel includes in PATH"
> +echo "  --user-mode-stacksize=   set default stack size in bytes (as -s, only in usermode)"
>  echo ""
>  echo "NOTE: The object files are built at the place where configure is launched"
>  exit 1
> @@ -2481,6 +2485,16 @@ if test "$target_user_only" = "yes" -a "$static" = "no" -a \
>    ldflags="-pie $ldflags"
>  fi
>  
> +# change default stacksize in usermode
> +#
> +if test "$target_user_only" = "yes" -a "$user_mode_stacksize" != "" ; then
> + cflags="-DUSER_MODE_STACKSIZE=$user_mode_stacksize $cflags"
> + echo "user_mode_stack   $user_mode_stacksize"
> +else
> + echo "user_mode_stack   default"
> +fi
> +
> +
>  if test "$target_softmmu" = "yes" -a \( \
>          "$TARGET_ARCH" = "microblaze" -o \
>          "$TARGET_ARCH" = "cris" \) ; then
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 81a1ada..9ac2421 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -51,7 +51,10 @@ const char *qemu_uname_release = CONFIG_UNAME_RELEASE;
>  /* XXX: on x86 MAP_GROWSDOWN only works if ESP <= address + 32, so
>     we allocate a bigger stack. Need a better solution, for example
>     by remapping the process stack directly at the right place */
> -unsigned long x86_stack_size = 512 * 1024;
> +#ifndef USER_MODE_STACKSIZE
> +#define USER_MODE_STACKSIZE (512 * 1024)
> +#endif
> +unsigned long x86_stack_size = USER_MODE_STACKSIZE;
>  
>  void gemu_log(const char *fmt, ...)
>  {