drm/i915/kvmgt: Add kvmgt debugfs entry nr_cache_entries under vgpu

Add a new debugfs entry kvmgt_nr_cache_entries under vgpu which shows
the number of entry in dma cache.

$ cat /sys/kernel/debug/gvt/vgpu1/kvmgt_nr_cache_entries
10101

v3: fix compiling error for some configuration. (Xiong Zhang <xiong.y.zhang@intel.com>)
v2: keep debugfs layout flat.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

diff --git a/drivers/gpu/drm/i915/gvt/gvt.h b/drivers/gpu/drm/i915/gvt/gvt.h
index eda41448c1963dac9e454e57bd149496f950a82c..efacd8abbedc2748ca9f58bedebb44b2ee897c9b 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/gvt.h
+++ b/drivers/gpu/drm/i915/gvt/gvt.h
@@ -208,6 +208,7 @@ 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 99a8ff3fe75a2edb717351d198cb18bc48e3696c..8a428678e4b5e87369f72adc2d9b34f14bac653b 100644 (file)
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -41,6 +41,7 @@
 #include <linux/kvm_host.h>
 #include <linux/vfio.h>
 #include <linux/mdev.h>
+#include <linux/debugfs.h>
 
 #include "i915_drv.h"
 #include "gvt.h"
@@ -84,6 +85,7 @@ struct kvmgt_guest_info {
 #define NR_BKT (1 << 18)
        struct hlist_head ptable[NR_BKT];
 #undef NR_BKT
+       struct dentry *debugfs_cache_entries;
 };
 
 struct gvt_dma {
@@ -225,6 +227,8 @@ 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 +237,7 @@ 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 +263,7 @@ 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);
 }
 
@@ -1493,11 +1499,20 @@ 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);
 
+       info->debugfs_cache_entries = debugfs_create_ulong(
+                                               "kvmgt_nr_cache_entries",
+                                               0444, vgpu->debugfs,
+                                               &vgpu->vdev.nr_cache_entries);
+       if (!info->debugfs_cache_entries)
+               gvt_vgpu_err("Cannot create kvmgt debugfs entry\n");
+
        return 0;
 }
 
 static bool kvmgt_guest_exit(struct kvmgt_guest_info *info)
 {
+       debugfs_remove(info->debugfs_cache_entries);
+
        kvm_page_track_unregister_notifier(info->kvm, &info->track_node);
        kvm_put_kvm(info->kvm);
        kvmgt_protect_table_destroy(info);