mm: LKSM: remove unnecessary debug messages

In order to get scanning candidates, LKSM hooks fork and exit calls even though
LKSM does not run. Previous patches include debugging messages when LKSM hooks
exit calls, and it can flush old kernel logs. To handle this, this patch removes
unnecessary debugging messages.

Change-Id: If475a880ee931668b6bebf53322622ba2a042c89
Signed-off-by: Sung-hun Kim <sfoon.kim@samsung.com>

diff --git a/mm/lksm.c b/mm/lksm.c
index e65cf12..e6a1533 100644 (file)
--- a/mm/lksm.c
+++ b/mm/lksm.c
@@ -1034,7 +1034,6 @@ static void lksm_region_free(struct lksm_region *region)
 {
        unsigned long flags;
 
-       ksm_debug("lets free region(%p) prev(%p)", region, region->prev);
        spin_lock_irqsave(&lksm_region_lock, flags);
        if (!region->next) {
                if (region->prev) {
@@ -1043,12 +1042,8 @@ static void lksm_region_free(struct lksm_region *region)
                                if (region->prev->len > SINGLE_FILTER_LEN)
                                        kfree(region->prev->filter);
                                kfree(region->prev);
-                       } else {
-                               ksm_debug("prev region(%p) has ref count(%d)",
-                                               region->prev,
-                                               atomic_read(&region->prev->refcount));
+                       } else
                                region->prev->next = NULL;
-                       }
                }
                hash_del(&region->hnode);
                if (region->len > SINGLE_FILTER_LEN)
@@ -1070,7 +1065,6 @@ static void lksm_region_ref_list_release(struct mm_slot *slot)
 {
        struct lksm_region_ref *ref, *next;
 
-       ksm_debug("release %p ref list", slot);
        list_for_each_entry_safe(ref, next, &slot->ref_list, list) {
                lksm_region_ref_remove(ref);
        }
@@ -2826,7 +2820,6 @@ static void lksm_flush_removed_mm_list(void)
 
        if (!list_empty(&head->mm_list)) {
                list_for_each_entry_safe(slot, next, &head->mm_list, mm_list) {
-                       ksm_debug("slot(%p) will be freed", slot);
                        list_del(&slot->mm_list);
 
                        cond_resched();
@@ -2841,8 +2834,6 @@ static void lksm_flush_removed_mm_list(void)
                }
        }
 
-       ksm_debug("slot(%p) will be freed", head);
-
        cond_resched();
        remove_trailing_rmap_items(head, &head->rmap_list);
        clear_bit(MMF_VM_MERGEABLE, &head->mm->flags);
@@ -2873,7 +2864,6 @@ static struct mm_slot *lksm_get_unscanned_mm_slot(struct mm_slot *slot)
        list_for_each_entry_safe_continue(slot, next, &ksm_scan_head.scan_list,
                        scan_list) {
                if (ksm_test_exit(slot->mm)) {
-                       ksm_debug("slot:%p %p is moved to remove list", slot, slot->mm);
                        if (lksm_test_mm_state(slot, KSM_MM_FROZEN))
                                atomic_dec(&ksm_scan.nr_frozen);
                        else
@@ -2985,14 +2975,12 @@ static struct vm_area_struct *lksm_find_next_vma
                                        region->len = SINGLE_FILTER_LEN;
                                        /* conflicted regions will be unfiltered */
                                        region = &unknown_region;
-                                       ksm_debug("the region is frequently conflicted. break.");
                                        break;
                                }
                                if (region->len < len) {
                                        unsigned long *filter;
                                        ksm_debug("size of region(%p) is changed: %d -> %d (size: %d)",
                                                        region, region->len, len, size);
-                                       ksm_debug("region-%d type: %d vma:%p", region->ino, region->type, vma);
                                        filter = kcalloc(len, sizeof(long), GFP_KERNEL);
                                        if (!filter) {
                                                ksm_err("fail to allocate memory for filter");
@@ -4072,13 +4060,10 @@ void __ksm_exit(struct mm_struct *mm)
                        easy_to_free = 1;
                } else
                        lksm_remove_mm_slot(mm_slot);
-               if (lksm_test_mm_state(mm_slot, KSM_MM_FROZEN)) {
+               if (lksm_test_mm_state(mm_slot, KSM_MM_FROZEN))
                        atomic_dec(&ksm_scan.nr_frozen);
-                       ksm_debug("nr_frozen: %d", atomic_read(&ksm_scan.nr_frozen));
-               } else if (!lksm_test_mm_state(mm_slot, KSM_MM_SCANNED)) {
+               else if (!lksm_test_mm_state(mm_slot, KSM_MM_SCANNED))
                        atomic_dec(&ksm_scan.nr_scannable);
-                       ksm_debug("nr_scannable: %d", atomic_read(&ksm_scan.nr_scannable));
-               }
        }
 #ifdef CONFIG_LKSM_FILTER
 deferring_free:
@@ -5028,8 +5013,6 @@ static struct lksm_region *lksm_find_region(struct vm_area_struct *vma)
 
        if (region && type == LKSM_REGION_FILE2) {
                if (!region->next) {
-                       ksm_debug("region(%p:%lu:%s)-vma(%p) doesn't have next area (file: %p)",
-                                       region, ino, region_type_str[region->type], vma, file);
                        lksm_insert_region(&region, ino, vma, type);
                        BUG_ON(!region->next);
                }
@@ -5069,17 +5052,11 @@ void lksm_remove_candidate(struct mm_struct *mm)
                                atomic_dec(&ksm_scan.nr_frozen);
                        else if (!lksm_test_mm_state(mm_slot, KSM_MM_SCANNED))
                                atomic_dec(&ksm_scan.nr_scannable);
-                       ksm_debug("mm_slot: %p will be exited", mm_slot);
                }
                spin_unlock(&ksm_mmlist_lock);
                return;
        }
 
-       if (!ksm_test_exit(mm))
-               ksm_debug("proc-%d(%s) will be removed",
-                               task_pid_nr(mm->owner), mm->owner->comm);
-
-       ksm_debug("proc-%d(%s) is exited", task_pid_nr(mm->owner), mm->owner->comm);
        spin_lock(&frozen_task_lock);
        ret = __lksm_remove_candidate(mm->owner);
        spin_unlock(&frozen_task_lock);