[PATCH 1/4] mm/ksm: rename mm_slot members to ksm_slot for better readability.
From: alexs
Date: Sun Apr 28 2024 - 06:03:10 EST
From: "Alex Shi (tencent)" <alexs@xxxxxxxxxx>
mm_slot is a struct of mm, and ksm_mm_slot is named the same again in
ksm_scan struct. Furthermore, the ksm_mm_slot pointer is named as
mm_slot again in functions, beside with 'struct mm_slot' variable.
That makes code readability pretty worse.
struct ksm_mm_slot {
struct mm_slot slot;
...
};
struct ksm_scan {
struct ksm_mm_slot *mm_slot;
...
};
int __ksm_enter(struct mm_struct *mm)
{
struct ksm_mm_slot *mm_slot;
struct mm_slot *slot;
...
So let's rename the mm_slot member to ksm_slot in ksm_scan, and ksm_slot
for ksm_mm_slot* type variables in functions to reduce this confusing.
struct ksm_scan {
- struct ksm_mm_slot *mm_slot;
+ struct ksm_mm_slot *ksm_slot;
Signed-off-by: Alex Shi (tencent) <alexs@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
---
mm/ksm.c | 84 ++++++++++++++++++++++++++++----------------------------
1 file changed, 42 insertions(+), 42 deletions(-)
diff --git a/mm/ksm.c b/mm/ksm.c
index 486c9974f8e2..d2c4eb98816d 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -131,7 +131,7 @@ struct ksm_mm_slot {
/**
* struct ksm_scan - cursor for scanning
- * @mm_slot: the current mm_slot we are scanning
+ * @ksm_slot: the current ksm_slot we are scanning
* @address: the next address inside that to be scanned
* @rmap_list: link to the next rmap to be scanned in the rmap_list
* @seqnr: count of completed full scans (needed when removing unstable node)
@@ -139,7 +139,7 @@ struct ksm_mm_slot {
* There is only the one ksm_scan instance of this cursor structure.
*/
struct ksm_scan {
- struct ksm_mm_slot *mm_slot;
+ struct ksm_mm_slot *ksm_slot;
unsigned long address;
struct ksm_rmap_item **rmap_list;
unsigned long seqnr;
@@ -187,7 +187,7 @@ struct ksm_stable_node {
/**
* struct ksm_rmap_item - reverse mapping item for virtual addresses
- * @rmap_list: next rmap_item in mm_slot's singly-linked rmap_list
+ * @rmap_list: next rmap_item in ksm_slot's singly-linked rmap_list
* @anon_vma: pointer to anon_vma for this mm,address, when in stable tree
* @nid: NUMA node id of unstable tree in which linked (may not match page)
* @mm: the memory structure this rmap_item is pointing into
@@ -242,7 +242,7 @@ static struct ksm_mm_slot ksm_mm_head = {
.slot.mm_node = LIST_HEAD_INIT(ksm_mm_head.slot.mm_node),
};
static struct ksm_scan ksm_scan = {
- .mm_slot = &ksm_mm_head,
+ .ksm_slot = &ksm_mm_head,
};
static struct kmem_cache *rmap_item_cache;
@@ -1205,11 +1205,11 @@ static int unmerge_and_remove_all_rmap_items(void)
spin_lock(&ksm_mmlist_lock);
slot = list_entry(ksm_mm_head.slot.mm_node.next,
struct mm_slot, mm_node);
- ksm_scan.mm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
+ ksm_scan.ksm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
spin_unlock(&ksm_mmlist_lock);
- for (mm_slot = ksm_scan.mm_slot; mm_slot != &ksm_mm_head;
- mm_slot = ksm_scan.mm_slot) {
+ for (mm_slot = ksm_scan.ksm_slot; mm_slot != &ksm_mm_head;
+ mm_slot = ksm_scan.ksm_slot) {
VMA_ITERATOR(vmi, mm_slot->slot.mm, 0);
mm = mm_slot->slot.mm;
@@ -1238,7 +1238,7 @@ static int unmerge_and_remove_all_rmap_items(void)
spin_lock(&ksm_mmlist_lock);
slot = list_entry(mm_slot->slot.mm_node.next,
struct mm_slot, mm_node);
- ksm_scan.mm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
+ ksm_scan.ksm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
if (ksm_test_exit(mm)) {
hash_del(&mm_slot->slot.hash);
list_del(&mm_slot->slot.mm_node);
@@ -1260,7 +1260,7 @@ static int unmerge_and_remove_all_rmap_items(void)
error:
mmap_read_unlock(mm);
spin_lock(&ksm_mmlist_lock);
- ksm_scan.mm_slot = &ksm_mm_head;
+ ksm_scan.ksm_slot = &ksm_mm_head;
spin_unlock(&ksm_mmlist_lock);
return err;
}
@@ -2565,7 +2565,7 @@ static bool should_skip_rmap_item(struct page *page,
static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page)
{
struct mm_struct *mm;
- struct ksm_mm_slot *mm_slot;
+ struct ksm_mm_slot *ksm_slot;
struct mm_slot *slot;
struct vm_area_struct *vma;
struct ksm_rmap_item *rmap_item;
@@ -2575,8 +2575,8 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page)
if (list_empty(&ksm_mm_head.slot.mm_node))
return NULL;
- mm_slot = ksm_scan.mm_slot;
- if (mm_slot == &ksm_mm_head) {
+ ksm_slot = ksm_scan.ksm_slot;
+ if (ksm_slot == &ksm_mm_head) {
advisor_start_scan();
trace_ksm_start_scan(ksm_scan.seqnr, ksm_rmap_items);
@@ -2616,23 +2616,23 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page)
root_unstable_tree[nid] = RB_ROOT;
spin_lock(&ksm_mmlist_lock);
- slot = list_entry(mm_slot->slot.mm_node.next,
+ slot = list_entry(ksm_slot->slot.mm_node.next,
struct mm_slot, mm_node);
- mm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
- ksm_scan.mm_slot = mm_slot;
+ ksm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
+ ksm_scan.ksm_slot = ksm_slot;
spin_unlock(&ksm_mmlist_lock);
/*
* Although we tested list_empty() above, a racing __ksm_exit
* of the last mm on the list may have removed it since then.
*/
- if (mm_slot == &ksm_mm_head)
+ if (ksm_slot == &ksm_mm_head)
return NULL;
next_mm:
ksm_scan.address = 0;
- ksm_scan.rmap_list = &mm_slot->rmap_list;
+ ksm_scan.rmap_list = &ksm_slot->rmap_list;
}
- slot = &mm_slot->slot;
+ slot = &ksm_slot->slot;
mm = slot->mm;
vma_iter_init(&vmi, mm, ksm_scan.address);
@@ -2662,7 +2662,7 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page)
if (PageAnon(*page)) {
flush_anon_page(vma, *page, ksm_scan.address);
flush_dcache_page(*page);
- rmap_item = get_next_rmap_item(mm_slot,
+ rmap_item = get_next_rmap_item(ksm_slot,
ksm_scan.rmap_list, ksm_scan.address);
if (rmap_item) {
ksm_scan.rmap_list =
@@ -2687,7 +2687,7 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page)
if (ksm_test_exit(mm)) {
no_vmas:
ksm_scan.address = 0;
- ksm_scan.rmap_list = &mm_slot->rmap_list;
+ ksm_scan.rmap_list = &ksm_slot->rmap_list;
}
/*
* Nuke all the rmap_items that are above this current rmap:
@@ -2696,9 +2696,9 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page)
remove_trailing_rmap_items(ksm_scan.rmap_list);
spin_lock(&ksm_mmlist_lock);
- slot = list_entry(mm_slot->slot.mm_node.next,
+ slot = list_entry(ksm_slot->slot.mm_node.next,
struct mm_slot, mm_node);
- ksm_scan.mm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
+ ksm_scan.ksm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
if (ksm_scan.address == 0) {
/*
* We've completed a full scan of all vmas, holding mmap_lock
@@ -2709,11 +2709,11 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page)
* or when all VM_MERGEABLE areas have been unmapped (and
* mmap_lock then protects against race with MADV_MERGEABLE).
*/
- hash_del(&mm_slot->slot.hash);
- list_del(&mm_slot->slot.mm_node);
+ hash_del(&ksm_slot->slot.hash);
+ list_del(&ksm_slot->slot.mm_node);
spin_unlock(&ksm_mmlist_lock);
- mm_slot_free(mm_slot_cache, mm_slot);
+ mm_slot_free(mm_slot_cache, ksm_slot);
clear_bit(MMF_VM_MERGEABLE, &mm->flags);
clear_bit(MMF_VM_MERGE_ANY, &mm->flags);
mmap_read_unlock(mm);
@@ -2725,14 +2725,14 @@ static struct ksm_rmap_item *scan_get_next_rmap_item(struct page **page)
* spin_unlock(&ksm_mmlist_lock) run, the "mm" may
* already have been freed under us by __ksm_exit()
* because the "mm_slot" is still hashed and
- * ksm_scan.mm_slot doesn't point to it anymore.
+ * ksm_scan.ksm_slot doesn't point to it anymore.
*/
spin_unlock(&ksm_mmlist_lock);
}
/* Repeat until we've completed scanning the whole list */
- mm_slot = ksm_scan.mm_slot;
- if (mm_slot != &ksm_mm_head)
+ ksm_slot = ksm_scan.ksm_slot;
+ if (ksm_slot != &ksm_mm_head)
goto next_mm;
advisor_stop_scan();
@@ -2968,15 +2968,15 @@ EXPORT_SYMBOL_GPL(ksm_madvise);
int __ksm_enter(struct mm_struct *mm)
{
- struct ksm_mm_slot *mm_slot;
+ struct ksm_mm_slot *ksm_slot;
struct mm_slot *slot;
int needs_wakeup;
- mm_slot = mm_slot_alloc(mm_slot_cache);
- if (!mm_slot)
+ ksm_slot = mm_slot_alloc(mm_slot_cache);
+ if (!ksm_slot)
return -ENOMEM;
- slot = &mm_slot->slot;
+ slot = &ksm_slot->slot;
/* Check ksm_run too? Would need tighter locking */
needs_wakeup = list_empty(&ksm_mm_head.slot.mm_node);
@@ -2996,7 +2996,7 @@ int __ksm_enter(struct mm_struct *mm)
if (ksm_run & KSM_RUN_UNMERGE)
list_add_tail(&slot->mm_node, &ksm_mm_head.slot.mm_node);
else
- list_add_tail(&slot->mm_node, &ksm_scan.mm_slot->slot.mm_node);
+ list_add_tail(&slot->mm_node, &ksm_scan.ksm_slot->slot.mm_node);
spin_unlock(&ksm_mmlist_lock);
set_bit(MMF_VM_MERGEABLE, &mm->flags);
@@ -3011,40 +3011,40 @@ int __ksm_enter(struct mm_struct *mm)
void __ksm_exit(struct mm_struct *mm)
{
- struct ksm_mm_slot *mm_slot;
+ struct ksm_mm_slot *ksm_slot;
struct mm_slot *slot;
int easy_to_free = 0;
/*
* This process is exiting: if it's straightforward (as is the
- * case when ksmd was never running), free mm_slot immediately.
+ * case when ksmd was never running), free ksm_slot immediately.
* But if it's at the cursor or has rmap_items linked to it, use
* mmap_lock to synchronize with any break_cows before pagetables
- * are freed, and leave the mm_slot on the list for ksmd to free.
+ * are freed, and leave the ksm_slot on the list for ksmd to free.
* Beware: ksm may already have noticed it exiting and freed the slot.
*/
spin_lock(&ksm_mmlist_lock);
slot = mm_slot_lookup(mm_slots_hash, mm);
- mm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
- if (mm_slot && ksm_scan.mm_slot != mm_slot) {
- if (!mm_slot->rmap_list) {
+ ksm_slot = mm_slot_entry(slot, struct ksm_mm_slot, slot);
+ if (ksm_slot && ksm_scan.ksm_slot != ksm_slot) {
+ if (!ksm_slot->rmap_list) {
hash_del(&slot->hash);
list_del(&slot->mm_node);
easy_to_free = 1;
} else {
list_move(&slot->mm_node,
- &ksm_scan.mm_slot->slot.mm_node);
+ &ksm_scan.ksm_slot->slot.mm_node);
}
}
spin_unlock(&ksm_mmlist_lock);
if (easy_to_free) {
- mm_slot_free(mm_slot_cache, mm_slot);
+ mm_slot_free(mm_slot_cache, ksm_slot);
clear_bit(MMF_VM_MERGE_ANY, &mm->flags);
clear_bit(MMF_VM_MERGEABLE, &mm->flags);
mmdrop(mm);
- } else if (mm_slot) {
+ } else if (ksm_slot) {
mmap_write_lock(mm);
mmap_write_unlock(mm);
}
--
2.43.0