Re: [PATCH 1/8] iommu/vt-d: Clean up unused PASID updating functions

2021-09-29 Thread Fenghua Yu
Hi, Baolu,

On Wed, Sep 29, 2021 at 03:34:51PM +0800, Lu Baolu wrote:
> On 2021/9/21 3:23, Fenghua Yu wrote:
> > update_pasid() and its call chain are currently unused in the tree because
> > Thomas disabled the ENQCMD feature. The feature will be re-enabled shortly
> > using a different approach and update_pasid() and its call chain will not
> > be used in the new approach.
> > 
> > Remove the useless functions.
> > 
> > Signed-off-by: Fenghua Yu 
> > Reviewed-by: Tony Luck 
> 
> Thanks for this cleanup. I have queued it for v5.16.

Thank you for pushing this patch to 5.16!

-Fenghua
___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu


Re: [PATCH 1/8] iommu/vt-d: Clean up unused PASID updating functions

2021-09-29 Thread Lu Baolu

Hi Fenghua,

On 2021/9/21 3:23, Fenghua Yu wrote:

update_pasid() and its call chain are currently unused in the tree because
Thomas disabled the ENQCMD feature. The feature will be re-enabled shortly
using a different approach and update_pasid() and its call chain will not
be used in the new approach.

Remove the useless functions.

Signed-off-by: Fenghua Yu 
Reviewed-by: Tony Luck 


Thanks for this cleanup. I have queued it for v5.16.

Best regards,
baolu


---
  arch/x86/include/asm/fpu/api.h |  2 --
  drivers/iommu/intel/svm.c  | 24 +---
  2 files changed, 1 insertion(+), 25 deletions(-)

diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h
index 23bef08a8388..ca4d0dee1ecd 100644
--- a/arch/x86/include/asm/fpu/api.h
+++ b/arch/x86/include/asm/fpu/api.h
@@ -106,6 +106,4 @@ extern int cpu_has_xfeatures(u64 xfeatures_mask, const char 
**feature_name);
   */
  #define PASID_DISABLED0
  
-static inline void update_pasid(void) { }

-
  #endif /* _ASM_X86_FPU_API_H */
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 0c228787704f..5b5d69b04fcc 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -505,21 +505,6 @@ int intel_svm_unbind_gpasid(struct device *dev, u32 pasid)
return ret;
  }
  
-static void _load_pasid(void *unused)

-{
-   update_pasid();
-}
-
-static void load_pasid(struct mm_struct *mm, u32 pasid)
-{
-   mutex_lock(&mm->context.lock);
-
-   /* Update PASID MSR on all CPUs running the mm's tasks. */
-   on_each_cpu_mask(mm_cpumask(mm), _load_pasid, NULL, true);
-
-   mutex_unlock(&mm->context.lock);
-}
-
  static int intel_svm_alloc_pasid(struct device *dev, struct mm_struct *mm,
 unsigned int flags)
  {
@@ -614,10 +599,6 @@ static struct iommu_sva *intel_svm_bind_mm(struct 
intel_iommu *iommu,
if (ret)
goto free_sdev;
  
-	/* The newly allocated pasid is loaded to the mm. */

-   if (!(flags & SVM_FLAG_SUPERVISOR_MODE) && list_empty(&svm->devs))
-   load_pasid(mm, svm->pasid);
-
list_add_rcu(&sdev->list, &svm->devs);
  success:
return &sdev->sva;
@@ -670,11 +651,8 @@ static int intel_svm_unbind_mm(struct device *dev, u32 
pasid)
kfree_rcu(sdev, rcu);
  
  			if (list_empty(&svm->devs)) {

-   if (svm->notifier.ops) {
+   if (svm->notifier.ops)
mmu_notifier_unregister(&svm->notifier, 
mm);
-   /* Clear mm's pasid. */
-   load_pasid(mm, PASID_DISABLED);
-   }
pasid_private_remove(svm->pasid);
/* We mandate that no page faults may be 
outstanding
 * for the PASID when intel_svm_unbind_mm() is 
called.


___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu


[PATCH 1/8] iommu/vt-d: Clean up unused PASID updating functions

2021-09-20 Thread Fenghua Yu
update_pasid() and its call chain are currently unused in the tree because
Thomas disabled the ENQCMD feature. The feature will be re-enabled shortly
using a different approach and update_pasid() and its call chain will not
be used in the new approach.

Remove the useless functions.

Signed-off-by: Fenghua Yu 
Reviewed-by: Tony Luck 
---
 arch/x86/include/asm/fpu/api.h |  2 --
 drivers/iommu/intel/svm.c  | 24 +---
 2 files changed, 1 insertion(+), 25 deletions(-)

diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h
index 23bef08a8388..ca4d0dee1ecd 100644
--- a/arch/x86/include/asm/fpu/api.h
+++ b/arch/x86/include/asm/fpu/api.h
@@ -106,6 +106,4 @@ extern int cpu_has_xfeatures(u64 xfeatures_mask, const char 
**feature_name);
  */
 #define PASID_DISABLED 0
 
-static inline void update_pasid(void) { }
-
 #endif /* _ASM_X86_FPU_API_H */
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 0c228787704f..5b5d69b04fcc 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -505,21 +505,6 @@ int intel_svm_unbind_gpasid(struct device *dev, u32 pasid)
return ret;
 }
 
-static void _load_pasid(void *unused)
-{
-   update_pasid();
-}
-
-static void load_pasid(struct mm_struct *mm, u32 pasid)
-{
-   mutex_lock(&mm->context.lock);
-
-   /* Update PASID MSR on all CPUs running the mm's tasks. */
-   on_each_cpu_mask(mm_cpumask(mm), _load_pasid, NULL, true);
-
-   mutex_unlock(&mm->context.lock);
-}
-
 static int intel_svm_alloc_pasid(struct device *dev, struct mm_struct *mm,
 unsigned int flags)
 {
@@ -614,10 +599,6 @@ static struct iommu_sva *intel_svm_bind_mm(struct 
intel_iommu *iommu,
if (ret)
goto free_sdev;
 
-   /* The newly allocated pasid is loaded to the mm. */
-   if (!(flags & SVM_FLAG_SUPERVISOR_MODE) && list_empty(&svm->devs))
-   load_pasid(mm, svm->pasid);
-
list_add_rcu(&sdev->list, &svm->devs);
 success:
return &sdev->sva;
@@ -670,11 +651,8 @@ static int intel_svm_unbind_mm(struct device *dev, u32 
pasid)
kfree_rcu(sdev, rcu);
 
if (list_empty(&svm->devs)) {
-   if (svm->notifier.ops) {
+   if (svm->notifier.ops)
mmu_notifier_unregister(&svm->notifier, 
mm);
-   /* Clear mm's pasid. */
-   load_pasid(mm, PASID_DISABLED);
-   }
pasid_private_remove(svm->pasid);
/* We mandate that no page faults may be 
outstanding
 * for the PASID when intel_svm_unbind_mm() is 
called.
-- 
2.33.0

___
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu