This routine is a one-liner and doesn't really need to be function and
can be implemented as a macro.
Suggested-by: Dave Martin <[email protected]>
Reviewed-by: Dave Martin <[email protected]>
Signed-off-by: Viresh Kumar <[email protected]>
---
V2->V3:
- Pass "vqs" instead of "&vqs" to vq_present().
- Added Reviewed-by from Dave.
V1->V2:
- The previous implementation was fixing a compilation error that
occurred only with old compilers (from 2015) due to a bug in the
compiler itself.
- Dave suggested to rather implement this as a macro which made more
sense.
arch/arm64/kvm/guest.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 3ae2f82fca46..ae734fcfd4ea 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -207,13 +207,7 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64)
#define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64)
-
-static bool vq_present(
- const u64 (*const vqs)[KVM_ARM64_SVE_VLS_WORDS],
- unsigned int vq)
-{
- return (*vqs)[vq_word(vq)] & vq_mask(vq);
-}
+#define vq_present(vqs, vq) ((vqs)[vq_word(vq)] & vq_mask(vq))
static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
@@ -258,7 +252,7 @@ static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
max_vq = 0;
for (vq = SVE_VQ_MIN; vq <= SVE_VQ_MAX; ++vq)
- if (vq_present(&vqs, vq))
+ if (vq_present(vqs, vq))
max_vq = vq;
if (max_vq > sve_vq_from_vl(kvm_sve_max_vl))
@@ -272,7 +266,7 @@ static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
* maximum:
*/
for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
- if (vq_present(&vqs, vq) != sve_vq_available(vq))
+ if (vq_present(vqs, vq) != sve_vq_available(vq))
return -EINVAL;
/* Can't run with no vector lengths at all: */
--
2.21.0.rc0.269.g1a574e7a288b
Hi guys,
I can't start up KVM guest os with SVE feature with your patch.
The error message is
qemu-system-aarch64: kvm_init_vcpu failed: Invalid argument.
My test enviroment.
kernel linux-5.2-rc6
qemu [Qemu-devel] [PATCH v2 00/14] target/arm/kvm: enable SVE in guests https://lists.gnu.org/archive/html/qemu-devel/2019-06/msg04945.html
KVM start up option
-machine virt,gic-version=host,accel=kvm \
-cpu host \
-machine type=virt \
-nographic \
-smp 16 \ -m 4096 \
-drive if=none,file=/root/image.qcow2,id=hd0,format=qcow2 \
-device virtio-blk-device,drive=hd0 \
-netdev user,id=mynet0,restrict=off,hostfwd=tcp::38001-:22 \
-device virtio-net-device,netdev=mynet0 \
-bios /root/QEMU_EFI.fd
sve_vq_available function's return value' type is bool.
But vq_present is macro, so the value is not only TRUE, FALSE but also some numbers.
So It failed at
if (vq_present(vqs, vq) != sve_vq_available(vq)).
I think it is nessary to make vq_present macro's value only TRUE and FALSE.
arch/arm64/kvm/guest.c
static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
if (vq_present(vqs, vq) != sve_vq_available(vq))$B!!(B// It failed at here.
return -EINVAL;
My patch as follows.
I have started up KVM guest os successfully with SVE feature with this patch.
Could you review and merge my patch?
Signed-off-by: Zhang Lei <[email protected]>
---
arch/arm64/kvm/guest.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index c2afa79..dfd6264 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -208,7 +208,7 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
#define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64) #define vq_mask(vq) ((u64)1 << ((vq) - SVE_VQ_MIN) % 64) -#define vq_present(vqs, vq) ((vqs)[vq_word(vq)] & vq_mask(vq))
+#define vq_present(vqs, vq) (!!((vqs)[vq_word(vq)] & vq_mask(vq)))
static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) {
--
1.8.3.1
> -----Original Message-----
> From: linux-arm-kernel <[email protected]> On
> Behalf Of Viresh Kumar
> Sent: Monday, June 10, 2019 7:00 PM
> To: Marc Zyngier <[email protected]>; James Morse
> <[email protected]>; Julien Thierry <[email protected]>; Suzuki K
> Pouloze <[email protected]>; Catalin Marinas
> <[email protected]>; Will Deacon <[email protected]>
> Cc: Viresh Kumar <[email protected]>; [email protected];
> [email protected]; Dave Martin <[email protected]>;
> [email protected]
> Subject: [PATCH V3] KVM: arm64: Implement vq_present() as a macro
>
> This routine is a one-liner and doesn't really need to be function and can be
> implemented as a macro.
>
> Suggested-by: Dave Martin <[email protected]>
> Reviewed-by: Dave Martin <[email protected]>
> Signed-off-by: Viresh Kumar <[email protected]>
> ---
> V2->V3:
> - Pass "vqs" instead of "&vqs" to vq_present().
> - Added Reviewed-by from Dave.
>
> V1->V2:
> - The previous implementation was fixing a compilation error that
> occurred only with old compilers (from 2015) due to a bug in the
> compiler itself.
>
> - Dave suggested to rather implement this as a macro which made more
> sense.
>
> arch/arm64/kvm/guest.c | 12 +++---------
> 1 file changed, 3 insertions(+), 9 deletions(-)
>
> diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index
> 3ae2f82fca46..ae734fcfd4ea 100644
> --- a/arch/arm64/kvm/guest.c
> +++ b/arch/arm64/kvm/guest.c
> @@ -207,13 +207,7 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const
> struct kvm_one_reg *reg)
>
> #define vq_word(vq) (((vq) - SVE_VQ_MIN) / 64) #define vq_mask(vq)
> ((u64)1 << ((vq) - SVE_VQ_MIN) % 64)
> -
> -static bool vq_present(
> - const u64 (*const vqs)[KVM_ARM64_SVE_VLS_WORDS],
> - unsigned int vq)
> -{
> - return (*vqs)[vq_word(vq)] & vq_mask(vq);
> -}
> +#define vq_present(vqs, vq) ((vqs)[vq_word(vq)] & vq_mask(vq))
>
> static int get_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
> { @@ -258,7 +252,7 @@ static int set_sve_vls(struct kvm_vcpu *vcpu, const
> struct kvm_one_reg *reg)
>
> max_vq = 0;
> for (vq = SVE_VQ_MIN; vq <= SVE_VQ_MAX; ++vq)
> - if (vq_present(&vqs, vq))
> + if (vq_present(vqs, vq))
> max_vq = vq;
>
> if (max_vq > sve_vq_from_vl(kvm_sve_max_vl)) @@ -272,7 +266,7
> @@ static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg
> *reg)
> * maximum:
> */
> for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
> - if (vq_present(&vqs, vq) != sve_vq_available(vq))
> + if (vq_present(vqs, vq) != sve_vq_available(vq))
> return -EINVAL;
>
> /* Can't run with no vector lengths at all: */
> --
> 2.21.0.rc0.269.g1a574e7a288b
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Wed, Jul 03, 2019 at 12:04:11PM +0000, Zhang, Lei wrote:
> Hi guys,
>
> I can't start up KVM guest os with SVE feature with your patch.
> The error message is
> qemu-system-aarch64: kvm_init_vcpu failed: Invalid argument.
>
> My test enviroment.
> kernel linux-5.2-rc6
> qemu [Qemu-devel] [PATCH v2 00/14] target/arm/kvm: enable SVE in guests https://lists.gnu.org/archive/html/qemu-devel/2019-06/msg04945.html
> KVM start up option
> -machine virt,gic-version=host,accel=kvm \
> -cpu host \
> -machine type=virt \
> -nographic \
> -smp 16 \ -m 4096 \
> -drive if=none,file=/root/image.qcow2,id=hd0,format=qcow2 \
> -device virtio-blk-device,drive=hd0 \
> -netdev user,id=mynet0,restrict=off,hostfwd=tcp::38001-:22 \
> -device virtio-net-device,netdev=mynet0 \
> -bios /root/QEMU_EFI.fd
>
> sve_vq_available function's return value' type is bool.
> But vq_present is macro, so the value is not only TRUE, FALSE but also some numbers.
> So It failed at
> if (vq_present(vqs, vq) != sve_vq_available(vq)).
> I think it is nessary to make vq_present macro's value only TRUE and FALSE.
>
> arch/arm64/kvm/guest.c
> static int set_sve_vls(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
> for (vq = SVE_VQ_MIN; vq <= max_vq; ++vq)
> if (vq_present(vqs, vq) != sve_vq_available(vq)) // It failed at here.
> return -EINVAL;
>
> My patch as follows.
> I have started up KVM guest os successfully with SVE feature with this patch.
>
> Could you review and merge my patch?
[...]
Thanks for reporting this! It looks like we didn't realise we dropped
the implicit cast to bool when the result was returned from the original
version of vq_present().
Your fix looks sensible to me.
For the future, see Documentation/process/submitting-patches.rst for
guidance on how to prepare a patch for submission.
However, due to the fact that we're already at -rc7 I've written a
commit message for the patch and reposted [1]. Since the fix is yours,
I'll keep your authorship and S-o-B.
Please retest when you can (though the diff should be the same).
Note, your mail seems to be corrupted, but since the diff is a one-line
fix, I'm pretty confident I decoded it correctly. If anything looks
wrong, please let me know.
[...]
Cheers
---Dave
[1] [PATCH] KVM: arm64/sve: Fix vq_present() macro to yield a bool
http://lists.infradead.org/pipermail/linux-arm-kernel/2019-July/664745.html