diff mbox

[RFC,v7,12/16] configure: Use slow-path for atomic only when the softmmu is enabled

Message ID 1454059965-23402-13-git-send-email-a.rigo@virtualopensystems.com (mailing list archive)
State New, archived
Headers show

Commit Message

alvise rigo Jan. 29, 2016, 9:32 a.m. UTC
Use the new slow path for atomic instruction translation when the
softmmu is enabled.

At the moment only arm and aarch64 use the new LL/SC backend. It is
possible to disable such backed with --disable-arm-llsc-backend.

Suggested-by: Jani Kokkonen <jani.kokkonen@huawei.com>
Suggested-by: Claudio Fontana <claudio.fontana@huawei.com>
Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
---
 configure | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

Comments

Alex Bennée Feb. 18, 2016, 4:40 p.m. UTC | #1
Alvise Rigo <a.rigo@virtualopensystems.com> writes:

> Use the new slow path for atomic instruction translation when the
> softmmu is enabled.
>
> At the moment only arm and aarch64 use the new LL/SC backend. It is
> possible to disable such backed with --disable-arm-llsc-backend.

Do we want to disable the backend once it is merged? Does it serve a
purpose other than to confuse the user?

>
> Suggested-by: Jani Kokkonen <jani.kokkonen@huawei.com>
> Suggested-by: Claudio Fontana <claudio.fontana@huawei.com>
> Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
> ---
>  configure | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
>
> diff --git a/configure b/configure
> index 44ac9ab..915efcc 100755
> --- a/configure
> +++ b/configure
> @@ -294,6 +294,7 @@ solaris="no"
>  profiler="no"
>  cocoa="no"
>  softmmu="yes"
> +arm_tcg_use_llsc="yes"
>  linux_user="no"
>  bsd_user="no"
>  aix="no"
> @@ -880,6 +881,10 @@ for opt do
>    ;;
>    --disable-debug-tcg) debug_tcg="no"
>    ;;
> +  --enable-arm-llsc-backend) arm_tcg_use_llsc="yes"
> +  ;;
> +  --disable-arm-llsc-backend) arm_tcg_use_llsc="no"
> +  ;;
>    --enable-debug)
>        # Enable debugging options that aren't excessively noisy
>        debug_tcg="yes"
> @@ -4751,6 +4756,7 @@ echo "host CPU          $cpu"
>  echo "host big endian   $bigendian"
>  echo "target list       $target_list"
>  echo "tcg debug enabled $debug_tcg"
> +echo "arm use llsc backend" $arm_tcg_use_llsc
>  echo "gprof enabled     $gprof"
>  echo "sparse enabled    $sparse"
>  echo "strip binaries    $strip_opt"
> @@ -4806,6 +4812,7 @@ echo "Install blobs     $blobs"
>  echo "KVM support       $kvm"
>  echo "RDMA support      $rdma"
>  echo "TCG interpreter   $tcg_interpreter"
> +echo "use ld/st excl    $softmmu"

I think we can drop everything above here.

>  echo "fdt support       $fdt"
>  echo "preadv support    $preadv"
>  echo "fdatasync         $fdatasync"
> @@ -5863,6 +5870,13 @@ fi
>  echo "LDFLAGS+=$ldflags" >> $config_target_mak
>  echo "QEMU_CFLAGS+=$cflags" >> $config_target_mak
>
> +# Use tcg LL/SC tcg backend for exclusive instruction is arm/aarch64
> +# softmmus targets
> +if test "$arm_tcg_use_llsc" = "yes" ; then
> +  if test "$target" = "arm-softmmu" ; then
> +    echo "CONFIG_ARM_USE_LDST_EXCL=y" >> $config_target_mak
> +  fi
> +fi

This isn't going to be just ARM specific and it will be progressively
turned on for other arches. So perhaps with the CONFIG_SOFTMMU section:

if test "$target_softmmu" = "yes" ; then
    echo "CONFIG_SOFTMMU=y" >> $config_target_mak

    # Use SoftMMU LL/SC primitives?
    case "$target_name" in
        arm | aarch64)
            echo "CONFIG_USE_LDST_EXCL=y" >> $config_target_mak
            ;;
    esac
fi


>  done # for target in $targets
>
>  if [ "$pixman" = "internal" ]; then


--
Alex Bennée
Alex Bennée Feb. 18, 2016, 4:43 p.m. UTC | #2
Alex Bennée <alex.bennee@linaro.org> writes:

> Alvise Rigo <a.rigo@virtualopensystems.com> writes:
>
>> Use the new slow path for atomic instruction translation when the
>> softmmu is enabled.
>>
>> At the moment only arm and aarch64 use the new LL/SC backend. It is
>> possible to disable such backed with --disable-arm-llsc-backend.
>
> Do we want to disable the backend once it is merged? Does it serve a
> purpose other than to confuse the user?

Also this needs to be after the actual implementation has been filled in
or you'll have a broken build!

>
>>
>> Suggested-by: Jani Kokkonen <jani.kokkonen@huawei.com>
>> Suggested-by: Claudio Fontana <claudio.fontana@huawei.com>
>> Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
>> ---
>>  configure | 14 ++++++++++++++
>>  1 file changed, 14 insertions(+)
>>
>> diff --git a/configure b/configure
>> index 44ac9ab..915efcc 100755
>> --- a/configure
>> +++ b/configure
>> @@ -294,6 +294,7 @@ solaris="no"
>>  profiler="no"
>>  cocoa="no"
>>  softmmu="yes"
>> +arm_tcg_use_llsc="yes"
>>  linux_user="no"
>>  bsd_user="no"
>>  aix="no"
>> @@ -880,6 +881,10 @@ for opt do
>>    ;;
>>    --disable-debug-tcg) debug_tcg="no"
>>    ;;
>> +  --enable-arm-llsc-backend) arm_tcg_use_llsc="yes"
>> +  ;;
>> +  --disable-arm-llsc-backend) arm_tcg_use_llsc="no"
>> +  ;;
>>    --enable-debug)
>>        # Enable debugging options that aren't excessively noisy
>>        debug_tcg="yes"
>> @@ -4751,6 +4756,7 @@ echo "host CPU          $cpu"
>>  echo "host big endian   $bigendian"
>>  echo "target list       $target_list"
>>  echo "tcg debug enabled $debug_tcg"
>> +echo "arm use llsc backend" $arm_tcg_use_llsc
>>  echo "gprof enabled     $gprof"
>>  echo "sparse enabled    $sparse"
>>  echo "strip binaries    $strip_opt"
>> @@ -4806,6 +4812,7 @@ echo "Install blobs     $blobs"
>>  echo "KVM support       $kvm"
>>  echo "RDMA support      $rdma"
>>  echo "TCG interpreter   $tcg_interpreter"
>> +echo "use ld/st excl    $softmmu"
>
> I think we can drop everything above here.
>
>>  echo "fdt support       $fdt"
>>  echo "preadv support    $preadv"
>>  echo "fdatasync         $fdatasync"
>> @@ -5863,6 +5870,13 @@ fi
>>  echo "LDFLAGS+=$ldflags" >> $config_target_mak
>>  echo "QEMU_CFLAGS+=$cflags" >> $config_target_mak
>>
>> +# Use tcg LL/SC tcg backend for exclusive instruction is arm/aarch64
>> +# softmmus targets
>> +if test "$arm_tcg_use_llsc" = "yes" ; then
>> +  if test "$target" = "arm-softmmu" ; then
>> +    echo "CONFIG_ARM_USE_LDST_EXCL=y" >> $config_target_mak
>> +  fi
>> +fi
>
> This isn't going to be just ARM specific and it will be progressively
> turned on for other arches. So perhaps with the CONFIG_SOFTMMU section:
>
> if test "$target_softmmu" = "yes" ; then
>     echo "CONFIG_SOFTMMU=y" >> $config_target_mak
>
>     # Use SoftMMU LL/SC primitives?
>     case "$target_name" in
>         arm | aarch64)
>             echo "CONFIG_USE_LDST_EXCL=y" >> $config_target_mak
>             ;;
>     esac
> fi
>
>
>>  done # for target in $targets
>>
>>  if [ "$pixman" = "internal" ]; then


--
Alex Bennée
alvise rigo March 7, 2016, 5:21 p.m. UTC | #3
On Thu, Feb 18, 2016 at 5:40 PM, Alex Bennée <alex.bennee@linaro.org> wrote:
>
> Alvise Rigo <a.rigo@virtualopensystems.com> writes:
>
>> Use the new slow path for atomic instruction translation when the
>> softmmu is enabled.
>>
>> At the moment only arm and aarch64 use the new LL/SC backend. It is
>> possible to disable such backed with --disable-arm-llsc-backend.
>
> Do we want to disable the backend once it is merged? Does it serve a
> purpose other than to confuse the user?

I added this option in order to have a quick way to compile a binary
with an without backend, it has been useful in the development
process. Now it's probably time to drop it.

Thank you,
alvise

>
>>
>> Suggested-by: Jani Kokkonen <jani.kokkonen@huawei.com>
>> Suggested-by: Claudio Fontana <claudio.fontana@huawei.com>
>> Signed-off-by: Alvise Rigo <a.rigo@virtualopensystems.com>
>> ---
>>  configure | 14 ++++++++++++++
>>  1 file changed, 14 insertions(+)
>>
>> diff --git a/configure b/configure
>> index 44ac9ab..915efcc 100755
>> --- a/configure
>> +++ b/configure
>> @@ -294,6 +294,7 @@ solaris="no"
>>  profiler="no"
>>  cocoa="no"
>>  softmmu="yes"
>> +arm_tcg_use_llsc="yes"
>>  linux_user="no"
>>  bsd_user="no"
>>  aix="no"
>> @@ -880,6 +881,10 @@ for opt do
>>    ;;
>>    --disable-debug-tcg) debug_tcg="no"
>>    ;;
>> +  --enable-arm-llsc-backend) arm_tcg_use_llsc="yes"
>> +  ;;
>> +  --disable-arm-llsc-backend) arm_tcg_use_llsc="no"
>> +  ;;
>>    --enable-debug)
>>        # Enable debugging options that aren't excessively noisy
>>        debug_tcg="yes"
>> @@ -4751,6 +4756,7 @@ echo "host CPU          $cpu"
>>  echo "host big endian   $bigendian"
>>  echo "target list       $target_list"
>>  echo "tcg debug enabled $debug_tcg"
>> +echo "arm use llsc backend" $arm_tcg_use_llsc
>>  echo "gprof enabled     $gprof"
>>  echo "sparse enabled    $sparse"
>>  echo "strip binaries    $strip_opt"
>> @@ -4806,6 +4812,7 @@ echo "Install blobs     $blobs"
>>  echo "KVM support       $kvm"
>>  echo "RDMA support      $rdma"
>>  echo "TCG interpreter   $tcg_interpreter"
>> +echo "use ld/st excl    $softmmu"
>
> I think we can drop everything above here.
>
>>  echo "fdt support       $fdt"
>>  echo "preadv support    $preadv"
>>  echo "fdatasync         $fdatasync"
>> @@ -5863,6 +5870,13 @@ fi
>>  echo "LDFLAGS+=$ldflags" >> $config_target_mak
>>  echo "QEMU_CFLAGS+=$cflags" >> $config_target_mak
>>
>> +# Use tcg LL/SC tcg backend for exclusive instruction is arm/aarch64
>> +# softmmus targets
>> +if test "$arm_tcg_use_llsc" = "yes" ; then
>> +  if test "$target" = "arm-softmmu" ; then
>> +    echo "CONFIG_ARM_USE_LDST_EXCL=y" >> $config_target_mak
>> +  fi
>> +fi
>
> This isn't going to be just ARM specific and it will be progressively
> turned on for other arches. So perhaps with the CONFIG_SOFTMMU section:
>
> if test "$target_softmmu" = "yes" ; then
>     echo "CONFIG_SOFTMMU=y" >> $config_target_mak
>
>     # Use SoftMMU LL/SC primitives?
>     case "$target_name" in
>         arm | aarch64)
>             echo "CONFIG_USE_LDST_EXCL=y" >> $config_target_mak
>             ;;
>     esac
> fi
>
>
>>  done # for target in $targets
>>
>>  if [ "$pixman" = "internal" ]; then
>
>
> --
> Alex Bennée
diff mbox

Patch

diff --git a/configure b/configure
index 44ac9ab..915efcc 100755
--- a/configure
+++ b/configure
@@ -294,6 +294,7 @@  solaris="no"
 profiler="no"
 cocoa="no"
 softmmu="yes"
+arm_tcg_use_llsc="yes"
 linux_user="no"
 bsd_user="no"
 aix="no"
@@ -880,6 +881,10 @@  for opt do
   ;;
   --disable-debug-tcg) debug_tcg="no"
   ;;
+  --enable-arm-llsc-backend) arm_tcg_use_llsc="yes"
+  ;;
+  --disable-arm-llsc-backend) arm_tcg_use_llsc="no"
+  ;;
   --enable-debug)
       # Enable debugging options that aren't excessively noisy
       debug_tcg="yes"
@@ -4751,6 +4756,7 @@  echo "host CPU          $cpu"
 echo "host big endian   $bigendian"
 echo "target list       $target_list"
 echo "tcg debug enabled $debug_tcg"
+echo "arm use llsc backend" $arm_tcg_use_llsc
 echo "gprof enabled     $gprof"
 echo "sparse enabled    $sparse"
 echo "strip binaries    $strip_opt"
@@ -4806,6 +4812,7 @@  echo "Install blobs     $blobs"
 echo "KVM support       $kvm"
 echo "RDMA support      $rdma"
 echo "TCG interpreter   $tcg_interpreter"
+echo "use ld/st excl    $softmmu"
 echo "fdt support       $fdt"
 echo "preadv support    $preadv"
 echo "fdatasync         $fdatasync"
@@ -5863,6 +5870,13 @@  fi
 echo "LDFLAGS+=$ldflags" >> $config_target_mak
 echo "QEMU_CFLAGS+=$cflags" >> $config_target_mak
 
+# Use tcg LL/SC tcg backend for exclusive instruction is arm/aarch64
+# softmmus targets
+if test "$arm_tcg_use_llsc" = "yes" ; then
+  if test "$target" = "arm-softmmu" ; then
+    echo "CONFIG_ARM_USE_LDST_EXCL=y" >> $config_target_mak
+  fi
+fi
 done # for target in $targets
 
 if [ "$pixman" = "internal" ]; then