AMD IOMMU: add stats counter for completion wait events

Impact: see number of completion wait events in debugfs

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index f98f70626bc64a6623ef6aee48a07bd1259195bd..b21435748e0d4ca0b7166058df9ee96971997879 100644 (file)
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -64,6 +64,8 @@ static struct dma_ops_domain *find_protection_domain(u16 devid);
  * Initialization code for statistics collection
  */
 
+DECLARE_STATS_COUNTER(compl_wait);
+
 static struct dentry *stats_dir;
 static struct dentry *de_isolate;
 static struct dentry *de_fflush;
@@ -88,6 +90,8 @@ static void amd_iommu_stats_init(void)
 
        de_fflush  = debugfs_create_bool("fullflush", 0444, stats_dir,
                                         (u32 *)&amd_iommu_unmap_flush);
+
+       amd_iommu_stats_add(&compl_wait);
 }
 
 #endif
@@ -249,6 +253,8 @@ static void __iommu_wait_for_completion(struct amd_iommu *iommu)
        unsigned status = 0;
        unsigned long i = 0;
 
+       INC_STATS_COUNTER(compl_wait);
+
        while (!ready && (i < EXIT_LOOP_COUNT)) {
                ++i;
                /* wait for the bit to become one */