Re: [PATCH 2/3] iommu/vt-d: Remove IOVA domain rcache flushing for CPU offlining

[Lu Baolu]

On 3/1/21 8:12 PM, John Garry wrote:

Now that the core code handles flushing per-IOVA domain CPU rcaches,
remove the handling here.

Signed-off-by: John Garry 
---
  drivers/iommu/intel/iommu.c | 31 ---
  include/linux/cpuhotplug.h  |  1 -
  2 files changed, 32 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index ee0932307d64..d1e66e1b07b8 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4065,35 +4065,6 @@ static struct notifier_block intel_iommu_memory_nb = {
.priority = 0
  };
  
-static void free_all_cpu_cached_iovas(unsigned int cpu)

-{
-   int i;
-
-   for (i = 0; i < g_num_of_iommus; i++) {
-   struct intel_iommu *iommu = g_iommus[i];
-   struct dmar_domain *domain;
-   int did;
-
-   if (!iommu)
-   continue;
-
-   for (did = 0; did < cap_ndoms(iommu->cap); did++) {
-   domain = get_iommu_domain(iommu, (u16)did);
-
-   if (!domain || domain->domain.type != IOMMU_DOMAIN_DMA)
-   continue;
-
-   iommu_dma_free_cpu_cached_iovas(cpu, >domain);
-   }
-   }
-}
-
-static int intel_iommu_cpu_dead(unsigned int cpu)
-{
-   free_all_cpu_cached_iovas(cpu);
-   return 0;
-}
-
  static void intel_disable_iommus(void)
  {
struct intel_iommu *iommu = NULL;
@@ -4388,8 +4359,6 @@ int __init intel_iommu_init(void)
bus_set_iommu(_bus_type, _iommu_ops);
if (si_domain && !hw_pass_through)
register_memory_notifier(_iommu_memory_nb);
-   cpuhp_setup_state(CPUHP_IOMMU_INTEL_DEAD, "iommu/intel:dead", NULL,
- intel_iommu_cpu_dead);
  
  	down_read(_global_lock);

if (probe_acpi_namespace_devices())
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index cedac9986557..85996494bec1 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -57,7 +57,6 @@ enum cpuhp_state {
CPUHP_PAGE_ALLOC_DEAD,
CPUHP_NET_DEV_DEAD,
CPUHP_PCI_XGENE_DEAD,
-   CPUHP_IOMMU_INTEL_DEAD,
CPUHP_IOMMU_IOVA_DEAD,
CPUHP_LUSTRE_CFS_DEAD,
CPUHP_AP_ARM_CACHE_B15_RAC_DEAD,



Reviewed-by: Lu Baolu 

Best regards,
baolu

[PATCH 2/3] iommu/vt-d: Remove IOVA domain rcache flushing for CPU offlining

[John Garry]

Now that the core code handles flushing per-IOVA domain CPU rcaches,
remove the handling here.

Signed-off-by: John Garry 
---
 drivers/iommu/intel/iommu.c | 31 ---
 include/linux/cpuhotplug.h  |  1 -
 2 files changed, 32 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index ee0932307d64..d1e66e1b07b8 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -4065,35 +4065,6 @@ static struct notifier_block intel_iommu_memory_nb = {
.priority = 0
 };
 
-static void free_all_cpu_cached_iovas(unsigned int cpu)
-{
-   int i;
-
-   for (i = 0; i < g_num_of_iommus; i++) {
-   struct intel_iommu *iommu = g_iommus[i];
-   struct dmar_domain *domain;
-   int did;
-
-   if (!iommu)
-   continue;
-
-   for (did = 0; did < cap_ndoms(iommu->cap); did++) {
-   domain = get_iommu_domain(iommu, (u16)did);
-
-   if (!domain || domain->domain.type != IOMMU_DOMAIN_DMA)
-   continue;
-
-   iommu_dma_free_cpu_cached_iovas(cpu, >domain);
-   }
-   }
-}
-
-static int intel_iommu_cpu_dead(unsigned int cpu)
-{
-   free_all_cpu_cached_iovas(cpu);
-   return 0;
-}
-
 static void intel_disable_iommus(void)
 {
struct intel_iommu *iommu = NULL;
@@ -4388,8 +4359,6 @@ int __init intel_iommu_init(void)
bus_set_iommu(_bus_type, _iommu_ops);
if (si_domain && !hw_pass_through)
register_memory_notifier(_iommu_memory_nb);
-   cpuhp_setup_state(CPUHP_IOMMU_INTEL_DEAD, "iommu/intel:dead", NULL,
- intel_iommu_cpu_dead);
 
down_read(_global_lock);
if (probe_acpi_namespace_devices())
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index cedac9986557..85996494bec1 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -57,7 +57,6 @@ enum cpuhp_state {
CPUHP_PAGE_ALLOC_DEAD,
CPUHP_NET_DEV_DEAD,
CPUHP_PCI_XGENE_DEAD,
-   CPUHP_IOMMU_INTEL_DEAD,
CPUHP_IOMMU_IOVA_DEAD,
CPUHP_LUSTRE_CFS_DEAD,
CPUHP_AP_ARM_CACHE_B15_RAC_DEAD,
-- 
2.26.2