[PATCH v2 2/2] drm/i915/kvmgt: Add kvmgt debugfs entry nr_cache_entries under vgpu

[Du, Changbin]

On Thu, Feb 08, 2018 at 11:22:25AM +0800, Zhenyu Wang wrote:
> On 2018.02.07 10:55:42 +0800, changbin.du at intel.com wrote:
> > From: Changbin Du <changbin.du at intel.com>
> > 
> > This patch add kvmgt folder under vgpu debugfs path and a new entry
> > nr_cache_entries which shows the number of entry in dma cache.
> > 
> > $ cat /sys/kernel/debug/gvt/vgpu1/kvmgt/nr_cache_entries
> > 10101
> >
> 
> I don't think it's necessary on another new directory level for kvmgt,
> if other hypervisor doesn't apply, simply would not exist, extra level
> just looks weird.
> 
I will not exist, and classifying in a folder simply the destroy code.

> > Signed-off-by: Changbin Du <changbin.du at intel.com>
> > ---
> >  drivers/gpu/drm/i915/gvt/gvt.h   |  1 +
> >  drivers/gpu/drm/i915/gvt/kvmgt.c | 22 ++++++++++++++++++++++
> >  2 files changed, 23 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
> > index 45209da..910f2a3 100644
> > --- a/drivers/gpu/drm/i915/gvt/gvt.h
> > +++ b/drivers/gpu/drm/i915/gvt/gvt.h
> > @@ -210,6 +210,7 @@ struct intel_vgpu {
> >  		 */
> >  		struct rb_root gfn_cache;
> >  		struct rb_root dma_addr_cache;
> > +		unsigned long nr_cache_entries;
> >  		struct mutex cache_lock;
> >  
> >  		struct notifier_block iommu_notifier;
> > diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
> > index e3629de..27752e3 100644
> > --- a/drivers/gpu/drm/i915/gvt/kvmgt.c
> > +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
> > @@ -84,6 +84,7 @@ struct kvmgt_guest_info {
> >  #define NR_BKT (1 << 18)
> >  	struct hlist_head ptable[NR_BKT];
> >  #undef NR_BKT
> > +	struct dentry *debugfs;
> >  };
> >  
> >  struct gvt_dma {
> > @@ -225,6 +226,8 @@ static void __gvt_cache_add(struct intel_vgpu *vgpu, gfn_t gfn,
> >  	}
> >  	rb_link_node(&new->dma_addr_node, parent, link);
> >  	rb_insert_color(&new->dma_addr_node, &vgpu->vdev.dma_addr_cache);
> > +
> > +	vgpu->vdev.nr_cache_entries++;
> >  }
> >  
> >  static void __gvt_cache_remove_entry(struct intel_vgpu *vgpu,
> > @@ -233,6 +236,7 @@ static void __gvt_cache_remove_entry(struct intel_vgpu *vgpu,
> >  	rb_erase(&entry->gfn_node, &vgpu->vdev.gfn_cache);
> >  	rb_erase(&entry->dma_addr_node, &vgpu->vdev.dma_addr_cache);
> >  	kfree(entry);
> > +	vgpu->vdev.nr_cache_entries--;
> >  }
> >  
> >  static void gvt_cache_destroy(struct intel_vgpu *vgpu)
> > @@ -258,6 +262,7 @@ static void gvt_cache_init(struct intel_vgpu *vgpu)
> >  {
> >  	vgpu->vdev.gfn_cache = RB_ROOT;
> >  	vgpu->vdev.dma_addr_cache = RB_ROOT;
> > +	vgpu->vdev.nr_cache_entries = 0;
> >  	mutex_init(&vgpu->vdev.cache_lock);
> >  }
> >  
> > @@ -1452,6 +1457,20 @@ static bool __kvmgt_vgpu_exist(struct intel_vgpu *vgpu, struct kvm *kvm)
> >  	return ret;
> >  }
> >  
> > +static void kvmgt_guest_debugfs_init(struct kvmgt_guest_info *info)
> > +{
> > +	struct intel_vgpu *vgpu = info->vgpu;
> > +
> > +	info->debugfs = debugfs_create_dir("kvmgt", vgpu->debugfs);
> > +	if (!info->debugfs) {
> > +		gvt_vgpu_err("Cannot create kvmgt debugfs dir\n");
> > +		return;
> > +	}
> > +
> > +	debugfs_create_ulong("nr_cache_entries", 0444, info->debugfs,
> > +			     &vgpu->vdev.nr_cache_entries);
> > +}
> > +
> >  static int kvmgt_guest_init(struct mdev_device *mdev)
> >  {
> >  	struct kvmgt_guest_info *info;
> > @@ -1490,11 +1509,14 @@ static int kvmgt_guest_init(struct mdev_device *mdev)
> >  	info->track_node.track_flush_slot = kvmgt_page_track_flush_slot;
> >  	kvm_page_track_register_notifier(kvm, &info->track_node);
> >  
> > +	kvmgt_guest_debugfs_init(info);
> > +
> >  	return 0;
> >  }
> >  
> >  static bool kvmgt_guest_exit(struct kvmgt_guest_info *info)
> >  {
> > +	debugfs_remove_recursive(info->debugfs);
> >  	kvm_page_track_unregister_notifier(info->kvm, &info->track_node);
> >  	kvm_put_kvm(info->kvm);
> >  	kvmgt_protect_table_destroy(info);
> > -- 
> > 2.7.4
> > 
> > _______________________________________________
> > intel-gvt-dev mailing list
> > intel-gvt-dev at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev
> 
> -- 
> Open Source Technology Center, Intel ltd.
> 
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-- 
Thanks,
Changbin Du