[v3,2/2] PCI: hv: Refactor hv_irq_unmask() to use cpumask_to_vpset()

Message ID 00e13af711510001e589c7b1ddd75beb99f58db5.1548745212.git.m.maya.nakamura@gmail.com
State Accepted
Delegated to: Lorenzo Pieralisi
Headers show
Series
  • PCI: hv: Refactor hv_irq_unmask() to use hv_vpset and cpumask_to_vpset()
Related show

Commit Message

Maya Nakamura Jan. 29, 2019, 7:20 a.m.
Remove the duplicate implementation of cpumask_to_vpset() and use the
shared implementation. Export hv_max_vp_index, which is required by
cpumask_to_vpset().

Apply changes to hv_irq_unmask() based on feedback.

Signed-off-by: Maya Nakamura <m.maya.nakamura@gmail.com>
---
Changes in v3:
 - Modify to catch all failures from cpumask_to_vpset().
 - Correct the v2 change log about the commit message.

Changes in v2:
 - Remove unnecessary nr_bank initialization.
 - Delete two unnecessary dev_err()'s.
 - Unlock before returning.
 - Update the commit message.

 arch/x86/hyperv/hv_init.c           |  1 +
 drivers/pci/controller/pci-hyperv.c | 38 +++++++++++++----------------
 2 files changed, 18 insertions(+), 21 deletions(-)

Comments

Vitaly Kuznetsov Feb. 27, 2019, 12:34 p.m. | #1
Maya Nakamura <m.maya.nakamura@gmail.com> writes:

> Remove the duplicate implementation of cpumask_to_vpset() and use the
> shared implementation. Export hv_max_vp_index, which is required by
> cpumask_to_vpset().
>
> Apply changes to hv_irq_unmask() based on feedback.
>

I just noticed an issue with this patch, sorry I've missed it before. I
don't see the commit in Linus' tree, not sure if we should amend this
one or a follow-up patch is needed.

> Signed-off-by: Maya Nakamura <m.maya.nakamura@gmail.com>
> ---
> Changes in v3:
>  - Modify to catch all failures from cpumask_to_vpset().
>  - Correct the v2 change log about the commit message.
>
> Changes in v2:
>  - Remove unnecessary nr_bank initialization.
>  - Delete two unnecessary dev_err()'s.
>  - Unlock before returning.
>  - Update the commit message.
>
>  arch/x86/hyperv/hv_init.c           |  1 +
>  drivers/pci/controller/pci-hyperv.c | 38 +++++++++++++----------------
>  2 files changed, 18 insertions(+), 21 deletions(-)
>
> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> index 7abb09e2eeb8..7f2eed1fc81b 100644
> --- a/arch/x86/hyperv/hv_init.c
> +++ b/arch/x86/hyperv/hv_init.c
> @@ -96,6 +96,7 @@ void  __percpu **hyperv_pcpu_input_arg;
>  EXPORT_SYMBOL_GPL(hyperv_pcpu_input_arg);
>  
>  u32 hv_max_vp_index;
> +EXPORT_SYMBOL_GPL(hv_max_vp_index);
>  
>  static int hv_cpu_init(unsigned int cpu)
>  {
> diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
> index da8b58d8630d..a78def332bbc 100644
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -391,8 +391,6 @@ struct hv_interrupt_entry {
>  	u32	data;
>  };
>  
> -#define HV_VP_SET_BANK_COUNT_MAX	5 /* current implementation limit */
> -
>  /*
>   * flags for hv_device_interrupt_target.flags
>   */
> @@ -908,12 +906,12 @@ static void hv_irq_unmask(struct irq_data *data)
>  	struct retarget_msi_interrupt *params;
>  	struct hv_pcibus_device *hbus;
>  	struct cpumask *dest;
> +	cpumask_var_t tmp;
>  	struct pci_bus *pbus;
>  	struct pci_dev *pdev;
>  	unsigned long flags;
>  	u32 var_size = 0;
> -	int cpu_vmbus;
> -	int cpu;
> +	int cpu, nr_bank;
>  	u64 res;
>  
>  	dest = irq_data_get_effective_affinity_mask(data);
> @@ -953,29 +951,27 @@ static void hv_irq_unmask(struct irq_data *data)
>  		 */
>  		params->int_target.flags |=
>  			HV_DEVICE_INTERRUPT_TARGET_PROCESSOR_SET;
> -		params->int_target.vp_set.valid_bank_mask =
> -			(1ull << HV_VP_SET_BANK_COUNT_MAX) - 1;
> +
> +		if (!alloc_cpumask_var(&tmp, GFP_KERNEL)) {

We can't use GFP_KERNEL here: this is happening under
hbus->retarget_msi_interrupt_lock spinlock, we should use GFP_ATOMIC
instead. It may, however, make sense to add the cpumask to a
pre-allocated structure (e.g. struct hv_pcibus_device) to make sure the
allocation never fails.

> +			res = 1;
> +			goto exit_unlock;
> +		}
> +
> +		cpumask_and(tmp, dest, cpu_online_mask);
> +		nr_bank = cpumask_to_vpset(&params->int_target.vp_set, tmp);
> +		free_cpumask_var(tmp);
> +
> +		if (nr_bank <= 0) {
> +			res = 1;
> +			goto exit_unlock;
> +		}
>  
>  		/*
>  		 * var-sized hypercall, var-size starts after vp_mask (thus
>  		 * vp_set.format does not count, but vp_set.valid_bank_mask
>  		 * does).
>  		 */
> -		var_size = 1 + HV_VP_SET_BANK_COUNT_MAX;
> -
> -		for_each_cpu_and(cpu, dest, cpu_online_mask) {
> -			cpu_vmbus = hv_cpu_number_to_vp_number(cpu);
> -
> -			if (cpu_vmbus >= HV_VP_SET_BANK_COUNT_MAX * 64) {
> -				dev_err(&hbus->hdev->device,
> -					"too high CPU %d", cpu_vmbus);
> -				res = 1;
> -				goto exit_unlock;
> -			}
> -
> -			params->int_target.vp_set.bank_contents[cpu_vmbus / 64]	|=
> -				(1ULL << (cpu_vmbus & 63));
> -		}
> +		var_size = 1 + nr_bank;
>  	} else {
>  		for_each_cpu_and(cpu, dest, cpu_online_mask) {
>  			params->int_target.vp_mask |=
Lorenzo Pieralisi Feb. 27, 2019, 2:28 p.m. | #2
On Wed, Feb 27, 2019 at 01:34:44PM +0100, Vitaly Kuznetsov wrote:
> Maya Nakamura <m.maya.nakamura@gmail.com> writes:
> 
> > Remove the duplicate implementation of cpumask_to_vpset() and use the
> > shared implementation. Export hv_max_vp_index, which is required by
> > cpumask_to_vpset().
> >
> > Apply changes to hv_irq_unmask() based on feedback.
> >
> 
> I just noticed an issue with this patch, sorry I've missed it before. I
> don't see the commit in Linus' tree, not sure if we should amend this
> one or a follow-up patch is needed.

I will drop this patch from the PCI queue, it does not make sense
to merge a patch adding a bug and fix it up later with a subsequent
one given that it is not upstream yet.

Lorenzo

> > Signed-off-by: Maya Nakamura <m.maya.nakamura@gmail.com>
> > ---
> > Changes in v3:
> >  - Modify to catch all failures from cpumask_to_vpset().
> >  - Correct the v2 change log about the commit message.
> >
> > Changes in v2:
> >  - Remove unnecessary nr_bank initialization.
> >  - Delete two unnecessary dev_err()'s.
> >  - Unlock before returning.
> >  - Update the commit message.
> >
> >  arch/x86/hyperv/hv_init.c           |  1 +
> >  drivers/pci/controller/pci-hyperv.c | 38 +++++++++++++----------------
> >  2 files changed, 18 insertions(+), 21 deletions(-)
> >
> > diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> > index 7abb09e2eeb8..7f2eed1fc81b 100644
> > --- a/arch/x86/hyperv/hv_init.c
> > +++ b/arch/x86/hyperv/hv_init.c
> > @@ -96,6 +96,7 @@ void  __percpu **hyperv_pcpu_input_arg;
> >  EXPORT_SYMBOL_GPL(hyperv_pcpu_input_arg);
> >  
> >  u32 hv_max_vp_index;
> > +EXPORT_SYMBOL_GPL(hv_max_vp_index);
> >  
> >  static int hv_cpu_init(unsigned int cpu)
> >  {
> > diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
> > index da8b58d8630d..a78def332bbc 100644
> > --- a/drivers/pci/controller/pci-hyperv.c
> > +++ b/drivers/pci/controller/pci-hyperv.c
> > @@ -391,8 +391,6 @@ struct hv_interrupt_entry {
> >  	u32	data;
> >  };
> >  
> > -#define HV_VP_SET_BANK_COUNT_MAX	5 /* current implementation limit */
> > -
> >  /*
> >   * flags for hv_device_interrupt_target.flags
> >   */
> > @@ -908,12 +906,12 @@ static void hv_irq_unmask(struct irq_data *data)
> >  	struct retarget_msi_interrupt *params;
> >  	struct hv_pcibus_device *hbus;
> >  	struct cpumask *dest;
> > +	cpumask_var_t tmp;
> >  	struct pci_bus *pbus;
> >  	struct pci_dev *pdev;
> >  	unsigned long flags;
> >  	u32 var_size = 0;
> > -	int cpu_vmbus;
> > -	int cpu;
> > +	int cpu, nr_bank;
> >  	u64 res;
> >  
> >  	dest = irq_data_get_effective_affinity_mask(data);
> > @@ -953,29 +951,27 @@ static void hv_irq_unmask(struct irq_data *data)
> >  		 */
> >  		params->int_target.flags |=
> >  			HV_DEVICE_INTERRUPT_TARGET_PROCESSOR_SET;
> > -		params->int_target.vp_set.valid_bank_mask =
> > -			(1ull << HV_VP_SET_BANK_COUNT_MAX) - 1;
> > +
> > +		if (!alloc_cpumask_var(&tmp, GFP_KERNEL)) {
> 
> We can't use GFP_KERNEL here: this is happening under
> hbus->retarget_msi_interrupt_lock spinlock, we should use GFP_ATOMIC
> instead. It may, however, make sense to add the cpumask to a
> pre-allocated structure (e.g. struct hv_pcibus_device) to make sure the
> allocation never fails.
> 
> > +			res = 1;
> > +			goto exit_unlock;
> > +		}
> > +
> > +		cpumask_and(tmp, dest, cpu_online_mask);
> > +		nr_bank = cpumask_to_vpset(&params->int_target.vp_set, tmp);
> > +		free_cpumask_var(tmp);
> > +
> > +		if (nr_bank <= 0) {
> > +			res = 1;
> > +			goto exit_unlock;
> > +		}
> >  
> >  		/*
> >  		 * var-sized hypercall, var-size starts after vp_mask (thus
> >  		 * vp_set.format does not count, but vp_set.valid_bank_mask
> >  		 * does).
> >  		 */
> > -		var_size = 1 + HV_VP_SET_BANK_COUNT_MAX;
> > -
> > -		for_each_cpu_and(cpu, dest, cpu_online_mask) {
> > -			cpu_vmbus = hv_cpu_number_to_vp_number(cpu);
> > -
> > -			if (cpu_vmbus >= HV_VP_SET_BANK_COUNT_MAX * 64) {
> > -				dev_err(&hbus->hdev->device,
> > -					"too high CPU %d", cpu_vmbus);
> > -				res = 1;
> > -				goto exit_unlock;
> > -			}
> > -
> > -			params->int_target.vp_set.bank_contents[cpu_vmbus / 64]	|=
> > -				(1ULL << (cpu_vmbus & 63));
> > -		}
> > +		var_size = 1 + nr_bank;
> >  	} else {
> >  		for_each_cpu_and(cpu, dest, cpu_online_mask) {
> >  			params->int_target.vp_mask |=
> 
> -- 
> Vitaly

Patch

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 7abb09e2eeb8..7f2eed1fc81b 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -96,6 +96,7 @@  void  __percpu **hyperv_pcpu_input_arg;
 EXPORT_SYMBOL_GPL(hyperv_pcpu_input_arg);
 
 u32 hv_max_vp_index;
+EXPORT_SYMBOL_GPL(hv_max_vp_index);
 
 static int hv_cpu_init(unsigned int cpu)
 {
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index da8b58d8630d..a78def332bbc 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -391,8 +391,6 @@  struct hv_interrupt_entry {
 	u32	data;
 };
 
-#define HV_VP_SET_BANK_COUNT_MAX	5 /* current implementation limit */
-
 /*
  * flags for hv_device_interrupt_target.flags
  */
@@ -908,12 +906,12 @@  static void hv_irq_unmask(struct irq_data *data)
 	struct retarget_msi_interrupt *params;
 	struct hv_pcibus_device *hbus;
 	struct cpumask *dest;
+	cpumask_var_t tmp;
 	struct pci_bus *pbus;
 	struct pci_dev *pdev;
 	unsigned long flags;
 	u32 var_size = 0;
-	int cpu_vmbus;
-	int cpu;
+	int cpu, nr_bank;
 	u64 res;
 
 	dest = irq_data_get_effective_affinity_mask(data);
@@ -953,29 +951,27 @@  static void hv_irq_unmask(struct irq_data *data)
 		 */
 		params->int_target.flags |=
 			HV_DEVICE_INTERRUPT_TARGET_PROCESSOR_SET;
-		params->int_target.vp_set.valid_bank_mask =
-			(1ull << HV_VP_SET_BANK_COUNT_MAX) - 1;
+
+		if (!alloc_cpumask_var(&tmp, GFP_KERNEL)) {
+			res = 1;
+			goto exit_unlock;
+		}
+
+		cpumask_and(tmp, dest, cpu_online_mask);
+		nr_bank = cpumask_to_vpset(&params->int_target.vp_set, tmp);
+		free_cpumask_var(tmp);
+
+		if (nr_bank <= 0) {
+			res = 1;
+			goto exit_unlock;
+		}
 
 		/*
 		 * var-sized hypercall, var-size starts after vp_mask (thus
 		 * vp_set.format does not count, but vp_set.valid_bank_mask
 		 * does).
 		 */
-		var_size = 1 + HV_VP_SET_BANK_COUNT_MAX;
-
-		for_each_cpu_and(cpu, dest, cpu_online_mask) {
-			cpu_vmbus = hv_cpu_number_to_vp_number(cpu);
-
-			if (cpu_vmbus >= HV_VP_SET_BANK_COUNT_MAX * 64) {
-				dev_err(&hbus->hdev->device,
-					"too high CPU %d", cpu_vmbus);
-				res = 1;
-				goto exit_unlock;
-			}
-
-			params->int_target.vp_set.bank_contents[cpu_vmbus / 64]	|=
-				(1ULL << (cpu_vmbus & 63));
-		}
+		var_size = 1 + nr_bank;
 	} else {
 		for_each_cpu_and(cpu, dest, cpu_online_mask) {
 			params->int_target.vp_mask |=