x86: add PAT related debug prints

Adds debug prints at critical code. Adds enough info in dmesg to allow us to
do effective first round of analysis of any issues that may result due to PAT
patch series.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 24 insertions, 0 deletions

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 7cc71d868483..57a2af36d6ee 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -246,6 +246,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
                 struct memtype *saved_ptr;
 
                 if (parse->start >= end) {
+                        printk("New Entry\n");
                         list_add(&new_entry->nd, parse->nd.prev);
                         new_entry = NULL;
                         break;
@@ -295,6 +296,8 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
                                 break;
                         }
 
+                        printk("Overlap at 0x%Lx-0x%Lx\n",
+                               saved_ptr->start, saved_ptr->end);
                         /* No conflict. Go ahead and add this new entry */
                         list_add(&new_entry->nd, saved_ptr->nd.prev);
                         new_entry = NULL;
@@ -345,6 +348,8 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
                                 break;
                         }
 
+                        printk("Overlap at 0x%Lx-0x%Lx\n",
+                               saved_ptr->start, saved_ptr->end);
                         /* No conflict. Go ahead and add this new entry */
                         list_add(&new_entry->nd, &saved_ptr->nd);
                         new_entry = NULL;
@@ -353,6 +358,10 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
         }
 
         if (err) {
+                printk(
+        "reserve_memtype failed 0x%Lx-0x%Lx, track %s, req %s\n",
+                        start, end, cattr_name(new_entry->type),
+                        cattr_name(req_type));
                 kfree(new_entry);
                 spin_unlock(&memtype_lock);
                 return err;
@@ -361,6 +370,19 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
         if (new_entry) {
                 /* No conflict. Not yet added to the list. Add to the tail */
                 list_add_tail(&new_entry->nd, &memtype_list);
+                printk("New Entry\n");
+        }
+
+        if (ret_type) {
+                printk(
+        "reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s, ret %s\n",
+                        start, end, cattr_name(actual_type),
+                        cattr_name(req_type), cattr_name(*ret_type));
+        } else {
+                printk(
+        "reserve_memtype added 0x%Lx-0x%Lx, track %s, req %s\n",
+                        start, end, cattr_name(actual_type),
+                        cattr_name(req_type));
         }
 
         spin_unlock(&memtype_lock);
@@ -397,6 +419,8 @@ int free_memtype(u64 start, u64 end)
                 printk(KERN_DEBUG "%s:%d freeing invalid memtype %Lx-%Lx\n",
                         current->comm, current->pid, start, end);
         }
+
+        printk( "free_memtype request 0x%Lx-0x%Lx\n", start, end);
         return err;
 }