2023-03-13 20:13:00

by Jaegeuk Kim

[permalink] [raw]
Subject: [PATCH 0/3] remove shared memory structures

This series removes the use of rb_entry based on memory alignment which doesn't
look like a right design when considering various architectures/compilers.

v2 from v1:
- adjusted Eric's review
- refactored gc.c further to clean up

Jaegeuk Kim (3):
f2fs: factor out victim_entry usage from general rb_tree use
f2fs: factor out discard_cmd usage from general rb_tree use
f2fs: remove entire rb_entry sharing

fs/f2fs/extent_cache.c | 241 ++++++++++++---------------------------
fs/f2fs/f2fs.h | 38 +------
fs/f2fs/gc.c | 139 ++++++++++++++---------
fs/f2fs/gc.h | 14 +--
fs/f2fs/segment.c | 252 +++++++++++++++++++++++++++--------------
5 files changed, 324 insertions(+), 360 deletions(-)

--
2.40.0.rc1.284.g88254d51c5-goog



2023-03-13 20:13:04

by Jaegeuk Kim

[permalink] [raw]
Subject: [PATCH 3/3] f2fs: remove entire rb_entry sharing

This is a last part to remove the memory sharing for rb_tree in extent_cache.

This should also fix arm32 memory alignment issue.

[struct extent_node] [struct rb_entry]
[0] struct rb_node rb_node; [0] struct rb_node rb_node;
union { union {
struct { struct {
[16] unsigned int fofs; [12] unsigned int ofs;
unsigned int len; unsigned int len;
};
unsigned long long key;
} __packed;

Cc: <[email protected]>
Fixes: 13054c548a1c ("f2fs: introduce infra macro and data structure of rb-tree extent cache")
Signed-off-by: Jaegeuk Kim <[email protected]>
---
fs/f2fs/extent_cache.c | 177 +++++++++++++++++------------------------
fs/f2fs/f2fs.h | 6 --
2 files changed, 71 insertions(+), 112 deletions(-)

diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index 5c206f941aac..9a8153895d20 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -161,95 +161,52 @@ static bool __is_front_mergeable(struct extent_info *cur,
return __is_extent_mergeable(cur, front, type);
}

-static struct rb_entry *__lookup_rb_tree_fast(struct rb_entry *cached_re,
- unsigned int ofs)
-{
- if (cached_re) {
- if (cached_re->ofs <= ofs &&
- cached_re->ofs + cached_re->len > ofs) {
- return cached_re;
- }
- }
- return NULL;
-}
-
-static struct rb_entry *__lookup_rb_tree_slow(struct rb_root_cached *root,
- unsigned int ofs)
+static struct extent_node *__lookup_extent_node(struct rb_root_cached *root,
+ struct extent_node *cached_en, unsigned int fofs)
{
struct rb_node *node = root->rb_root.rb_node;
- struct rb_entry *re;
+ struct extent_node *en;
+
+ /* check a cached entry */
+ if (cached_en && cached_en->ei.fofs <= fofs &&
+ cached_en->ei.fofs + cached_en->ei.len > fofs)
+ return cached_en;

+ /* check rb_tree */
while (node) {
- re = rb_entry(node, struct rb_entry, rb_node);
+ en = rb_entry(node, struct extent_node, rb_node);

- if (ofs < re->ofs)
+ if (fofs < en->ei.fofs)
node = node->rb_left;
- else if (ofs >= re->ofs + re->len)
+ else if (fofs >= en->ei.fofs + en->ei.len)
node = node->rb_right;
else
- return re;
+ return en;
}
return NULL;
}

-static struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
- struct rb_entry *cached_re, unsigned int ofs)
-{
- struct rb_entry *re;
-
- re = __lookup_rb_tree_fast(cached_re, ofs);
- if (!re)
- return __lookup_rb_tree_slow(root, ofs);
-
- return re;
-}
-
-static struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root,
- struct rb_node **parent,
- unsigned int ofs, bool *leftmost)
-{
- struct rb_node **p = &root->rb_root.rb_node;
- struct rb_entry *re;
-
- while (*p) {
- *parent = *p;
- re = rb_entry(*parent, struct rb_entry, rb_node);
-
- if (ofs < re->ofs) {
- p = &(*p)->rb_left;
- } else if (ofs >= re->ofs + re->len) {
- p = &(*p)->rb_right;
- *leftmost = false;
- } else {
- f2fs_bug_on(sbi, 1);
- }
- }
-
- return p;
-}
-
/*
- * lookup rb entry in position of @ofs in rb-tree,
+ * lookup rb entry in position of @fofs in rb-tree,
* if hit, return the entry, otherwise, return NULL
- * @prev_ex: extent before ofs
- * @next_ex: extent after ofs
- * @insert_p: insert point for new extent at ofs
+ * @prev_ex: extent before fofs
+ * @next_ex: extent after fofs
+ * @insert_p: insert point for new extent at fofs
* in order to simplify the insertion after.
* tree must stay unchanged between lookup and insertion.
*/
-static struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
- struct rb_entry *cached_re,
- unsigned int ofs,
- struct rb_entry **prev_entry,
- struct rb_entry **next_entry,
+static struct extent_node *__lookup_extent_node_ret(struct rb_root_cached *root,
+ struct extent_node *cached_en,
+ unsigned int fofs,
+ struct extent_node **prev_entry,
+ struct extent_node **next_entry,
struct rb_node ***insert_p,
struct rb_node **insert_parent,
- bool force, bool *leftmost)
+ bool *leftmost)
{
struct rb_node **pnode = &root->rb_root.rb_node;
struct rb_node *parent = NULL, *tmp_node;
- struct rb_entry *re = cached_re;
+ struct extent_node *en = cached_en;

*insert_p = NULL;
*insert_parent = NULL;
@@ -259,24 +216,20 @@ static struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
if (RB_EMPTY_ROOT(&root->rb_root))
return NULL;

- if (re) {
- if (re->ofs <= ofs && re->ofs + re->len > ofs)
- goto lookup_neighbors;
- }
+ if (en && en->ei.fofs <= fofs && en->ei.fofs + en->ei.len > fofs)
+ goto lookup_neighbors;

- if (leftmost)
- *leftmost = true;
+ *leftmost = true;

while (*pnode) {
parent = *pnode;
- re = rb_entry(*pnode, struct rb_entry, rb_node);
+ en = rb_entry(*pnode, struct extent_node, rb_node);

- if (ofs < re->ofs) {
+ if (fofs < en->ei.fofs) {
pnode = &(*pnode)->rb_left;
- } else if (ofs >= re->ofs + re->len) {
+ } else if (fofs >= en->ei.fofs + en->ei.len) {
pnode = &(*pnode)->rb_right;
- if (leftmost)
- *leftmost = false;
+ *leftmost = false;
} else {
goto lookup_neighbors;
}
@@ -285,30 +238,32 @@ static struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
*insert_p = pnode;
*insert_parent = parent;

- re = rb_entry(parent, struct rb_entry, rb_node);
+ en = rb_entry(parent, struct extent_node, rb_node);
tmp_node = parent;
- if (parent && ofs > re->ofs)
+ if (parent && fofs > en->ei.fofs)
tmp_node = rb_next(parent);
- *next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
+ *next_entry = rb_entry_safe(tmp_node, struct extent_node, rb_node);

tmp_node = parent;
- if (parent && ofs < re->ofs)
+ if (parent && fofs < en->ei.fofs)
tmp_node = rb_prev(parent);
- *prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
+ *prev_entry = rb_entry_safe(tmp_node, struct extent_node, rb_node);
return NULL;

lookup_neighbors:
- if (ofs == re->ofs || force) {
+ if (fofs == en->ei.fofs) {
/* lookup prev node for merging backward later */
- tmp_node = rb_prev(&re->rb_node);
- *prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
+ tmp_node = rb_prev(&en->rb_node);
+ *prev_entry = rb_entry_safe(tmp_node,
+ struct extent_node, rb_node);
}
- if (ofs == re->ofs + re->len - 1 || force) {
+ if (fofs == en->ei.fofs + en->ei.len - 1) {
/* lookup next node for merging frontward later */
- tmp_node = rb_next(&re->rb_node);
- *next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
+ tmp_node = rb_next(&en->rb_node);
+ *next_entry = rb_entry_safe(tmp_node,
+ struct extent_node, rb_node);
}
- return re;
+ return en;
}

static struct kmem_cache *extent_tree_slab;
@@ -523,8 +478,7 @@ static bool __lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
goto out;
}

- en = (struct extent_node *)f2fs_lookup_rb_tree(&et->root,
- (struct rb_entry *)et->cached_en, pgofs);
+ en = __lookup_extent_node(&et->root, et->cached_en, pgofs);
if (!en)
goto out;

@@ -598,7 +552,7 @@ static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,
bool leftmost)
{
struct extent_tree_info *eti = &sbi->extent_tree[et->type];
- struct rb_node **p;
+ struct rb_node **p = &et->root.rb_root.rb_node;
struct rb_node *parent = NULL;
struct extent_node *en = NULL;

@@ -610,8 +564,21 @@ static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,

leftmost = true;

- p = f2fs_lookup_rb_tree_for_insert(sbi, &et->root, &parent,
- ei->fofs, &leftmost);
+ /* look up extent_node in the rb tree */
+ while (*p) {
+ parent = *p;
+ en = rb_entry(parent, struct extent_node, rb_node);
+
+ if (ei->fofs < en->ei.fofs) {
+ p = &(*p)->rb_left;
+ } else if (ei->fofs >= en->ei.fofs + en->ei.len) {
+ p = &(*p)->rb_right;
+ leftmost = false;
+ } else {
+ f2fs_bug_on(sbi, 1);
+ }
+ }
+
do_insert:
en = __attach_extent_node(sbi, et, ei, parent, p, leftmost);
if (!en)
@@ -670,11 +637,10 @@ static void __update_extent_tree_range(struct inode *inode,
}

/* 1. lookup first extent node in range [fofs, fofs + len - 1] */
- en = (struct extent_node *)f2fs_lookup_rb_tree_ret(&et->root,
- (struct rb_entry *)et->cached_en, fofs,
- (struct rb_entry **)&prev_en,
- (struct rb_entry **)&next_en,
- &insert_p, &insert_parent, false,
+ en = __lookup_extent_node_ret(&et->root,
+ et->cached_en, fofs,
+ &prev_en, &next_en,
+ &insert_p, &insert_parent,
&leftmost);
if (!en)
en = next_en;
@@ -812,12 +778,11 @@ void f2fs_update_read_extent_tree_range_compressed(struct inode *inode,

write_lock(&et->lock);

- en = (struct extent_node *)f2fs_lookup_rb_tree_ret(&et->root,
- (struct rb_entry *)et->cached_en, fofs,
- (struct rb_entry **)&prev_en,
- (struct rb_entry **)&next_en,
- &insert_p, &insert_parent, false,
- &leftmost);
+ en = __lookup_extent_node_ret(&et->root,
+ et->cached_en, fofs,
+ &prev_en, &next_en,
+ &insert_p, &insert_parent,
+ &leftmost);
if (en)
goto unlock_out;

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 6e04fea9c34f..90a67feddcdc 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -620,12 +620,6 @@ enum extent_type {
NR_EXTENT_CACHES,
};

-struct rb_entry {
- struct rb_node rb_node; /* rb node located in rb-tree */
- unsigned int ofs; /* start offset of the entry */
- unsigned int len; /* length of the entry */
-};
-
struct extent_info {
unsigned int fofs; /* start offset in a file */
unsigned int len; /* length of the extent */
--
2.40.0.rc1.284.g88254d51c5-goog


2023-03-13 20:13:12

by Jaegeuk Kim

[permalink] [raw]
Subject: [PATCH 1/3] f2fs: factor out victim_entry usage from general rb_tree use

Let's reduce the complexity of mixed use of rb_tree in victim_entry from
extent_cache and discard_cmd.

This should fix arm32 memory alignment issue caused by shared rb_entry.

[struct victim_entry] [struct rb_entry]
[0] struct rb_node rb_node; [0] struct rb_node rb_node;
union {
struct {
unsigned int ofs;
unsigned int len;
};
[16] unsigned long long mtime; [12] unsigned long long key;
} __packed;

Cc: <[email protected]>
Fixes: 093749e296e2 ("f2fs: support age threshold based garbage collection")
Signed-off-by: Jaegeuk Kim <[email protected]>
---
fs/f2fs/extent_cache.c | 36 +----------
fs/f2fs/f2fs.h | 15 +----
fs/f2fs/gc.c | 139 +++++++++++++++++++++++++----------------
fs/f2fs/gc.h | 14 +----
fs/f2fs/segment.c | 4 +-
5 files changed, 93 insertions(+), 115 deletions(-)

diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index 28b12553f2b3..d1aa4609ca6b 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -204,29 +204,6 @@ struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
return re;
}

-struct rb_node **f2fs_lookup_rb_tree_ext(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root,
- struct rb_node **parent,
- unsigned long long key, bool *leftmost)
-{
- struct rb_node **p = &root->rb_root.rb_node;
- struct rb_entry *re;
-
- while (*p) {
- *parent = *p;
- re = rb_entry(*parent, struct rb_entry, rb_node);
-
- if (key < re->key) {
- p = &(*p)->rb_left;
- } else {
- p = &(*p)->rb_right;
- *leftmost = false;
- }
- }
-
- return p;
-}
-
struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
struct rb_root_cached *root,
struct rb_node **parent,
@@ -335,7 +312,7 @@ struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
}

bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root, bool check_key)
+ struct rb_root_cached *root)
{
#ifdef CONFIG_F2FS_CHECK_FS
struct rb_node *cur = rb_first_cached(root), *next;
@@ -352,23 +329,12 @@ bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
cur_re = rb_entry(cur, struct rb_entry, rb_node);
next_re = rb_entry(next, struct rb_entry, rb_node);

- if (check_key) {
- if (cur_re->key > next_re->key) {
- f2fs_info(sbi, "inconsistent rbtree, "
- "cur(%llu) next(%llu)",
- cur_re->key, next_re->key);
- return false;
- }
- goto next;
- }
-
if (cur_re->ofs + cur_re->len > next_re->ofs) {
f2fs_info(sbi, "inconsistent rbtree, cur(%u, %u) next(%u, %u)",
cur_re->ofs, cur_re->len,
next_re->ofs, next_re->len);
return false;
}
-next:
cur = next;
}
#endif
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 9c3ddebd28e3..9396549e112d 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -630,13 +630,8 @@ enum extent_type {

struct rb_entry {
struct rb_node rb_node; /* rb node located in rb-tree */
- union {
- struct {
- unsigned int ofs; /* start offset of the entry */
- unsigned int len; /* length of the entry */
- };
- unsigned long long key; /* 64-bits key */
- } __packed;
+ unsigned int ofs; /* start offset of the entry */
+ unsigned int len; /* length of the entry */
};

struct extent_info {
@@ -4139,10 +4134,6 @@ void f2fs_leave_shrinker(struct f2fs_sb_info *sbi);
bool sanity_check_extent_cache(struct inode *inode);
struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
struct rb_entry *cached_re, unsigned int ofs);
-struct rb_node **f2fs_lookup_rb_tree_ext(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root,
- struct rb_node **parent,
- unsigned long long key, bool *left_most);
struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
struct rb_root_cached *root,
struct rb_node **parent,
@@ -4153,7 +4144,7 @@ struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
struct rb_node ***insert_p, struct rb_node **insert_parent,
bool force, bool *leftmost);
bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root, bool check_key);
+ struct rb_root_cached *root);
void f2fs_init_extent_tree(struct inode *inode);
void f2fs_drop_extent_tree(struct inode *inode);
void f2fs_destroy_extent_node(struct inode *inode);
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 292a17d62f56..2996d38aa89c 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -390,40 +390,95 @@ static unsigned int count_bits(const unsigned long *addr,
return sum;
}

-static struct victim_entry *attach_victim_entry(struct f2fs_sb_info *sbi,
- unsigned long long mtime, unsigned int segno,
- struct rb_node *parent, struct rb_node **p,
- bool left_most)
+static bool f2fs_check_victim_tree(struct f2fs_sb_info *sbi,
+ struct rb_root_cached *root)
+{
+#ifdef CONFIG_F2FS_CHECK_FS
+ struct rb_node *cur = rb_first_cached(root), *next;
+ struct victim_entry *cur_ve, *next_ve;
+
+ while (cur) {
+ next = rb_next(cur);
+ if (!next)
+ return true;
+
+ cur_ve = rb_entry(cur, struct victim_entry, rb_node);
+ next_ve = rb_entry(next, struct victim_entry, rb_node);
+
+ if (cur_ve->mtime > next_ve->mtime) {
+ f2fs_info(sbi, "broken victim_rbtree, "
+ "cur_mtime(%llu) next_mtime(%llu)",
+ cur_ve->mtime, next_ve->mtime);
+ return false;
+ }
+ cur = next;
+ }
+#endif
+ return true;
+}
+
+static struct victim_entry *__lookup_victim_entry(struct f2fs_sb_info *sbi,
+ unsigned long long mtime)
+{
+ struct atgc_management *am = &sbi->am;
+ struct rb_node *node = am->root.rb_root.rb_node;
+ struct victim_entry *ve = NULL;
+
+ while (node) {
+ ve = rb_entry(node, struct victim_entry, rb_node);
+
+ if (mtime < ve->mtime)
+ node = node->rb_left;
+ else
+ node = node->rb_right;
+ }
+ return ve;
+}
+
+static struct victim_entry *__create_victim_entry(struct f2fs_sb_info *sbi,
+ unsigned long long mtime, unsigned int segno)
{
struct atgc_management *am = &sbi->am;
struct victim_entry *ve;

- ve = f2fs_kmem_cache_alloc(victim_entry_slab,
- GFP_NOFS, true, NULL);
+ ve = f2fs_kmem_cache_alloc(victim_entry_slab, GFP_NOFS, true, NULL);

ve->mtime = mtime;
ve->segno = segno;

- rb_link_node(&ve->rb_node, parent, p);
- rb_insert_color_cached(&ve->rb_node, &am->root, left_most);
-
list_add_tail(&ve->list, &am->victim_list);
-
am->victim_count++;

return ve;
}

-static void insert_victim_entry(struct f2fs_sb_info *sbi,
+static void __insert_victim_entry(struct f2fs_sb_info *sbi,
unsigned long long mtime, unsigned int segno)
{
struct atgc_management *am = &sbi->am;
- struct rb_node **p;
+ struct rb_root_cached *root = &am->root;
+ struct rb_node **p = &root->rb_root.rb_node;
struct rb_node *parent = NULL;
+ struct victim_entry *ve;
bool left_most = true;

- p = f2fs_lookup_rb_tree_ext(sbi, &am->root, &parent, mtime, &left_most);
- attach_victim_entry(sbi, mtime, segno, parent, p, left_most);
+ /* look up rb tree to find parent node */
+ while (*p) {
+ parent = *p;
+ ve = rb_entry(parent, struct victim_entry, rb_node);
+
+ if (mtime < ve->mtime) {
+ p = &(*p)->rb_left;
+ } else {
+ p = &(*p)->rb_right;
+ left_most = false;
+ }
+ }
+
+ ve = __create_victim_entry(sbi, mtime, segno);
+
+ rb_link_node(&ve->rb_node, parent, p);
+ rb_insert_color_cached(&ve->rb_node, root, left_most);
}

static void add_victim_entry(struct f2fs_sb_info *sbi,
@@ -459,19 +514,7 @@ static void add_victim_entry(struct f2fs_sb_info *sbi,
if (sit_i->dirty_max_mtime - mtime < p->age_threshold)
return;

- insert_victim_entry(sbi, mtime, segno);
-}
-
-static struct rb_node *lookup_central_victim(struct f2fs_sb_info *sbi,
- struct victim_sel_policy *p)
-{
- struct atgc_management *am = &sbi->am;
- struct rb_node *parent = NULL;
- bool left_most;
-
- f2fs_lookup_rb_tree_ext(sbi, &am->root, &parent, p->age, &left_most);
-
- return parent;
+ __insert_victim_entry(sbi, mtime, segno);
}

static void atgc_lookup_victim(struct f2fs_sb_info *sbi,
@@ -481,7 +524,6 @@ static void atgc_lookup_victim(struct f2fs_sb_info *sbi,
struct atgc_management *am = &sbi->am;
struct rb_root_cached *root = &am->root;
struct rb_node *node;
- struct rb_entry *re;
struct victim_entry *ve;
unsigned long long total_time;
unsigned long long age, u, accu;
@@ -508,12 +550,10 @@ static void atgc_lookup_victim(struct f2fs_sb_info *sbi,

node = rb_first_cached(root);
next:
- re = rb_entry_safe(node, struct rb_entry, rb_node);
- if (!re)
+ ve = rb_entry_safe(node, struct victim_entry, rb_node);
+ if (!ve)
return;

- ve = (struct victim_entry *)re;
-
if (ve->mtime >= max_mtime || ve->mtime < min_mtime)
goto skip;

@@ -555,8 +595,6 @@ static void atssr_lookup_victim(struct f2fs_sb_info *sbi,
{
struct sit_info *sit_i = SIT_I(sbi);
struct atgc_management *am = &sbi->am;
- struct rb_node *node;
- struct rb_entry *re;
struct victim_entry *ve;
unsigned long long age;
unsigned long long max_mtime = sit_i->dirty_max_mtime;
@@ -566,25 +604,22 @@ static void atssr_lookup_victim(struct f2fs_sb_info *sbi,
unsigned int dirty_threshold = max(am->max_candidate_count,
am->candidate_ratio *
am->victim_count / 100);
- unsigned int cost;
- unsigned int iter = 0;
+ unsigned int cost, iter;
int stage = 0;

if (max_mtime < min_mtime)
return;
max_mtime += 1;
next_stage:
- node = lookup_central_victim(sbi, p);
+ iter = 0;
+ ve = __lookup_victim_entry(sbi, p->age);
next_node:
- re = rb_entry_safe(node, struct rb_entry, rb_node);
- if (!re) {
- if (stage == 0)
- goto skip_stage;
+ if (!ve) {
+ if (stage++ == 0)
+ goto next_stage;
return;
}

- ve = (struct victim_entry *)re;
-
if (ve->mtime >= max_mtime || ve->mtime < min_mtime)
goto skip_node;

@@ -610,24 +645,20 @@ static void atssr_lookup_victim(struct f2fs_sb_info *sbi,
}
skip_node:
if (iter < dirty_threshold) {
- if (stage == 0)
- node = rb_prev(node);
- else if (stage == 1)
- node = rb_next(node);
+ ve = rb_entry(stage == 0 ? rb_prev(&ve->rb_node) :
+ rb_next(&ve->rb_node),
+ struct victim_entry, rb_node);
goto next_node;
}
-skip_stage:
- if (stage < 1) {
- stage++;
- iter = 0;
+
+ if (stage++ == 0)
goto next_stage;
- }
}
+
static void lookup_victim_by_age(struct f2fs_sb_info *sbi,
struct victim_sel_policy *p)
{
- f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
- &sbi->am.root, true));
+ f2fs_bug_on(sbi, !f2fs_check_victim_tree(sbi, &sbi->am.root));

if (p->gc_mode == GC_AT)
atgc_lookup_victim(sbi, p);
diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h
index 15bd1d680f67..5ad6ac63e13f 100644
--- a/fs/f2fs/gc.h
+++ b/fs/f2fs/gc.h
@@ -55,20 +55,10 @@ struct gc_inode_list {
struct radix_tree_root iroot;
};

-struct victim_info {
- unsigned long long mtime; /* mtime of section */
- unsigned int segno; /* section No. */
-};
-
struct victim_entry {
struct rb_node rb_node; /* rb node located in rb-tree */
- union {
- struct {
- unsigned long long mtime; /* mtime of section */
- unsigned int segno; /* segment No. */
- };
- struct victim_info vi; /* victim info */
- };
+ unsigned long long mtime; /* mtime of section */
+ unsigned int segno; /* segment No. */
struct list_head list;
};

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 227e25836173..e98a12e8dca1 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1478,7 +1478,7 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
goto next;
if (unlikely(dcc->rbtree_check))
f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
- &dcc->root, false));
+ &dcc->root));
blk_start_plug(&plug);
list_for_each_entry_safe(dc, tmp, pend_list, list) {
f2fs_bug_on(sbi, dc->state != D_PREP);
@@ -2965,7 +2965,7 @@ static unsigned int __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
mutex_lock(&dcc->cmd_lock);
if (unlikely(dcc->rbtree_check))
f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
- &dcc->root, false));
+ &dcc->root));

dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
NULL, start,
--
2.40.0.rc1.284.g88254d51c5-goog


2023-03-13 20:13:21

by Jaegeuk Kim

[permalink] [raw]
Subject: [PATCH 2/3] f2fs: factor out discard_cmd usage from general rb_tree use

This is a second part to remove the mixed use of rb_tree in discard_cmd from
extent_cache.

This should also fix arm32 memory alignment issue caused by shared rb_entry.

[struct discard_cmd] [struct rb_entry]
[0] struct rb_node rb_node; [0] struct rb_node rb_node;
union { union {
struct { struct {
[16] block_t lstart; [12] unsigned int ofs;
block_t len; unsigned int len;
};
unsigned long long key;
} __packed;

Cc: <[email protected]>
Fixes: 004b68621897 ("f2fs: use rb-tree to track pending discard commands")
Signed-off-by: Jaegeuk Kim <[email protected]>
---
fs/f2fs/extent_cache.c | 36 +-----
fs/f2fs/f2fs.h | 23 +---
fs/f2fs/segment.c | 252 +++++++++++++++++++++++++++--------------
3 files changed, 169 insertions(+), 142 deletions(-)

diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index d1aa4609ca6b..5c206f941aac 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -192,7 +192,7 @@ static struct rb_entry *__lookup_rb_tree_slow(struct rb_root_cached *root,
return NULL;
}

-struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
+static struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
struct rb_entry *cached_re, unsigned int ofs)
{
struct rb_entry *re;
@@ -204,7 +204,7 @@ struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
return re;
}

-struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
+static struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
struct rb_root_cached *root,
struct rb_node **parent,
unsigned int ofs, bool *leftmost)
@@ -238,7 +238,7 @@ struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
* in order to simplify the insertion after.
* tree must stay unchanged between lookup and insertion.
*/
-struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
+static struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
struct rb_entry *cached_re,
unsigned int ofs,
struct rb_entry **prev_entry,
@@ -311,36 +311,6 @@ struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
return re;
}

-bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root)
-{
-#ifdef CONFIG_F2FS_CHECK_FS
- struct rb_node *cur = rb_first_cached(root), *next;
- struct rb_entry *cur_re, *next_re;
-
- if (!cur)
- return true;
-
- while (cur) {
- next = rb_next(cur);
- if (!next)
- return true;
-
- cur_re = rb_entry(cur, struct rb_entry, rb_node);
- next_re = rb_entry(next, struct rb_entry, rb_node);
-
- if (cur_re->ofs + cur_re->len > next_re->ofs) {
- f2fs_info(sbi, "inconsistent rbtree, cur(%u, %u) next(%u, %u)",
- cur_re->ofs, cur_re->len,
- next_re->ofs, next_re->len);
- return false;
- }
- cur = next;
- }
-#endif
- return true;
-}
-
static struct kmem_cache *extent_tree_slab;
static struct kmem_cache *extent_node_slab;

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 9396549e112d..6e04fea9c34f 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -353,15 +353,7 @@ struct discard_info {

struct discard_cmd {
struct rb_node rb_node; /* rb node located in rb-tree */
- union {
- struct {
- block_t lstart; /* logical start address */
- block_t len; /* length */
- block_t start; /* actual start address in dev */
- };
- struct discard_info di; /* discard info */
-
- };
+ struct discard_info di; /* discard info */
struct list_head list; /* command list */
struct completion wait; /* compleation */
struct block_device *bdev; /* bdev */
@@ -4132,19 +4124,6 @@ void f2fs_leave_shrinker(struct f2fs_sb_info *sbi);
* extent_cache.c
*/
bool sanity_check_extent_cache(struct inode *inode);
-struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
- struct rb_entry *cached_re, unsigned int ofs);
-struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root,
- struct rb_node **parent,
- unsigned int ofs, bool *leftmost);
-struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
- struct rb_entry *cached_re, unsigned int ofs,
- struct rb_entry **prev_entry, struct rb_entry **next_entry,
- struct rb_node ***insert_p, struct rb_node **insert_parent,
- bool force, bool *leftmost);
-bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root);
void f2fs_init_extent_tree(struct inode *inode);
void f2fs_drop_extent_tree(struct inode *inode);
void f2fs_destroy_extent_node(struct inode *inode);
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index e98a12e8dca1..5f65c8110453 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -933,9 +933,9 @@ static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
dc = f2fs_kmem_cache_alloc(discard_cmd_slab, GFP_NOFS, true, NULL);
INIT_LIST_HEAD(&dc->list);
dc->bdev = bdev;
- dc->lstart = lstart;
- dc->start = start;
- dc->len = len;
+ dc->di.lstart = lstart;
+ dc->di.start = start;
+ dc->di.len = len;
dc->ref = 0;
dc->state = D_PREP;
dc->queued = 0;
@@ -950,20 +950,108 @@ static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
return dc;
}

-static struct discard_cmd *__attach_discard_cmd(struct f2fs_sb_info *sbi,
- struct block_device *bdev, block_t lstart,
- block_t start, block_t len,
- struct rb_node *parent, struct rb_node **p,
- bool leftmost)
+static bool f2fs_check_discard_tree(struct f2fs_sb_info *sbi)
{
+#ifdef CONFIG_F2FS_CHECK_FS
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
+ struct rb_node *cur = rb_first_cached(&dcc->root), *next;
+ struct discard_cmd *cur_dc, *next_dc;
+
+ while (cur) {
+ next = rb_next(cur);
+ if (!next)
+ return true;
+
+ cur_dc = rb_entry(cur, struct discard_cmd, rb_node);
+ next_dc = rb_entry(next, struct discard_cmd, rb_node);
+
+ if (cur_dc->di.lstart + cur_dc->di.len > next_dc->di.lstart) {
+ f2fs_info(sbi, "broken discard_rbtree, "
+ "cur(%u, %u) next(%u, %u)",
+ cur_dc->di.lstart, cur_dc->di.len,
+ next_dc->di.lstart, next_dc->di.len);
+ return false;
+ }
+ cur = next;
+ }
+#endif
+ return true;
+}
+
+static struct discard_cmd *__lookup_discard_cmd(struct f2fs_sb_info *sbi,
+ block_t blkaddr)
+{
+ struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
+ struct rb_node *node = dcc->root.rb_root.rb_node;
struct discard_cmd *dc;

- dc = __create_discard_cmd(sbi, bdev, lstart, start, len);
+ while (node) {
+ dc = rb_entry(node, struct discard_cmd, rb_node);

- rb_link_node(&dc->rb_node, parent, p);
- rb_insert_color_cached(&dc->rb_node, &dcc->root, leftmost);
+ if (blkaddr < dc->di.lstart)
+ node = node->rb_left;
+ else if (blkaddr >= dc->di.lstart + dc->di.len)
+ node = node->rb_right;
+ else
+ return dc;
+ }
+ return NULL;
+}
+
+static struct discard_cmd *__lookup_discard_cmd_ret(struct rb_root_cached *root,
+ block_t blkaddr,
+ struct discard_cmd **prev_entry,
+ struct discard_cmd **next_entry,
+ struct rb_node ***insert_p,
+ struct rb_node **insert_parent)
+{
+ struct rb_node **pnode = &root->rb_root.rb_node;
+ struct rb_node *parent = NULL, *tmp_node;
+ struct discard_cmd *dc;

+ *insert_p = NULL;
+ *insert_parent = NULL;
+ *prev_entry = NULL;
+ *next_entry = NULL;
+
+ if (RB_EMPTY_ROOT(&root->rb_root))
+ return NULL;
+
+ while (*pnode) {
+ parent = *pnode;
+ dc = rb_entry(*pnode, struct discard_cmd, rb_node);
+
+ if (blkaddr < dc->di.lstart)
+ pnode = &(*pnode)->rb_left;
+ else if (blkaddr >= dc->di.lstart + dc->di.len)
+ pnode = &(*pnode)->rb_right;
+ else
+ goto lookup_neighbors;
+ }
+
+ *insert_p = pnode;
+ *insert_parent = parent;
+
+ dc = rb_entry(parent, struct discard_cmd, rb_node);
+ tmp_node = parent;
+ if (parent && blkaddr > dc->di.lstart)
+ tmp_node = rb_next(parent);
+ *next_entry = rb_entry_safe(tmp_node, struct discard_cmd, rb_node);
+
+ tmp_node = parent;
+ if (parent && blkaddr < dc->di.lstart)
+ tmp_node = rb_prev(parent);
+ *prev_entry = rb_entry_safe(tmp_node, struct discard_cmd, rb_node);
+ return NULL;
+
+lookup_neighbors:
+ /* lookup prev node for merging backward later */
+ tmp_node = rb_prev(&dc->rb_node);
+ *prev_entry = rb_entry_safe(tmp_node, struct discard_cmd, rb_node);
+
+ /* lookup next node for merging frontward later */
+ tmp_node = rb_next(&dc->rb_node);
+ *next_entry = rb_entry_safe(tmp_node, struct discard_cmd, rb_node);
return dc;
}

@@ -975,7 +1063,7 @@ static void __detach_discard_cmd(struct discard_cmd_control *dcc,

list_del(&dc->list);
rb_erase_cached(&dc->rb_node, &dcc->root);
- dcc->undiscard_blks -= dc->len;
+ dcc->undiscard_blks -= dc->di.len;

kmem_cache_free(discard_cmd_slab, dc);

@@ -988,7 +1076,7 @@ static void __remove_discard_cmd(struct f2fs_sb_info *sbi,
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
unsigned long flags;

- trace_f2fs_remove_discard(dc->bdev, dc->start, dc->len);
+ trace_f2fs_remove_discard(dc->bdev, dc->di.start, dc->di.len);

spin_lock_irqsave(&dc->lock, flags);
if (dc->bio_ref) {
@@ -1006,7 +1094,7 @@ static void __remove_discard_cmd(struct f2fs_sb_info *sbi,
printk_ratelimited(
"%sF2FS-fs (%s): Issue discard(%u, %u, %u) failed, ret: %d",
KERN_INFO, sbi->sb->s_id,
- dc->lstart, dc->start, dc->len, dc->error);
+ dc->di.lstart, dc->di.start, dc->di.len, dc->error);
__detach_discard_cmd(dcc, dc);
}

@@ -1122,14 +1210,14 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi,
if (is_sbi_flag_set(sbi, SBI_NEED_FSCK))
return 0;

- trace_f2fs_issue_discard(bdev, dc->start, dc->len);
+ trace_f2fs_issue_discard(bdev, dc->di.start, dc->di.len);

- lstart = dc->lstart;
- start = dc->start;
- len = dc->len;
+ lstart = dc->di.lstart;
+ start = dc->di.start;
+ len = dc->di.len;
total_len = len;

- dc->len = 0;
+ dc->di.len = 0;

while (total_len && *issued < dpolicy->max_requests && !err) {
struct bio *bio = NULL;
@@ -1145,7 +1233,7 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi,
if (*issued == dpolicy->max_requests)
last = true;

- dc->len += len;
+ dc->di.len += len;

if (time_to_inject(sbi, FAULT_DISCARD)) {
err = -EIO;
@@ -1207,34 +1295,41 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi,
return err;
}

-static void __insert_discard_tree(struct f2fs_sb_info *sbi,
+static void __insert_discard_cmd(struct f2fs_sb_info *sbi,
struct block_device *bdev, block_t lstart,
- block_t start, block_t len,
- struct rb_node **insert_p,
- struct rb_node *insert_parent)
+ block_t start, block_t len)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
- struct rb_node **p;
+ struct rb_node **p = &dcc->root.rb_root.rb_node;
struct rb_node *parent = NULL;
+ struct discard_cmd *dc;
bool leftmost = true;

- if (insert_p && insert_parent) {
- parent = insert_parent;
- p = insert_p;
- goto do_insert;
+ /* look up rb tree to find parent node */
+ while (*p) {
+ parent = *p;
+ dc = rb_entry(parent, struct discard_cmd, rb_node);
+
+ if (lstart < dc->di.lstart) {
+ p = &(*p)->rb_left;
+ } else if (lstart >= dc->di.lstart + dc->di.len) {
+ p = &(*p)->rb_right;
+ leftmost = false;
+ } else {
+ f2fs_bug_on(sbi, 1);
+ }
}

- p = f2fs_lookup_rb_tree_for_insert(sbi, &dcc->root, &parent,
- lstart, &leftmost);
-do_insert:
- __attach_discard_cmd(sbi, bdev, lstart, start, len, parent,
- p, leftmost);
+ dc = __create_discard_cmd(sbi, bdev, lstart, start, len);
+
+ rb_link_node(&dc->rb_node, parent, p);
+ rb_insert_color_cached(&dc->rb_node, &dcc->root, leftmost);
}

static void __relocate_discard_cmd(struct discard_cmd_control *dcc,
struct discard_cmd *dc)
{
- list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->len)]);
+ list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->di.len)]);
}

static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
@@ -1244,7 +1339,7 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
struct discard_info di = dc->di;
bool modified = false;

- if (dc->state == D_DONE || dc->len == 1) {
+ if (dc->state == D_DONE || dc->di.len == 1) {
__remove_discard_cmd(sbi, dc);
return;
}
@@ -1252,23 +1347,22 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
dcc->undiscard_blks -= di.len;

if (blkaddr > di.lstart) {
- dc->len = blkaddr - dc->lstart;
- dcc->undiscard_blks += dc->len;
+ dc->di.len = blkaddr - dc->di.lstart;
+ dcc->undiscard_blks += dc->di.len;
__relocate_discard_cmd(dcc, dc);
modified = true;
}

if (blkaddr < di.lstart + di.len - 1) {
if (modified) {
- __insert_discard_tree(sbi, dc->bdev, blkaddr + 1,
+ __insert_discard_cmd(sbi, dc->bdev, blkaddr + 1,
di.start + blkaddr + 1 - di.lstart,
- di.lstart + di.len - 1 - blkaddr,
- NULL, NULL);
+ di.lstart + di.len - 1 - blkaddr);
} else {
- dc->lstart++;
- dc->len--;
- dc->start++;
- dcc->undiscard_blks += dc->len;
+ dc->di.lstart++;
+ dc->di.len--;
+ dc->di.start++;
+ dcc->undiscard_blks += dc->di.len;
__relocate_discard_cmd(dcc, dc);
}
}
@@ -1287,37 +1381,33 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
SECTOR_TO_BLOCK(bdev_max_discard_sectors(bdev));
block_t end = lstart + len;

- dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
- NULL, lstart,
- (struct rb_entry **)&prev_dc,
- (struct rb_entry **)&next_dc,
- &insert_p, &insert_parent, true, NULL);
+ dc = __lookup_discard_cmd_ret(&dcc->root, lstart,
+ &prev_dc, &next_dc, &insert_p, &insert_parent);
if (dc)
prev_dc = dc;

if (!prev_dc) {
di.lstart = lstart;
- di.len = next_dc ? next_dc->lstart - lstart : len;
+ di.len = next_dc ? next_dc->di.lstart - lstart : len;
di.len = min(di.len, len);
di.start = start;
}

while (1) {
struct rb_node *node;
- bool merged = false;
struct discard_cmd *tdc = NULL;

if (prev_dc) {
- di.lstart = prev_dc->lstart + prev_dc->len;
+ di.lstart = prev_dc->di.lstart + prev_dc->di.len;
if (di.lstart < lstart)
di.lstart = lstart;
if (di.lstart >= end)
break;

- if (!next_dc || next_dc->lstart > end)
+ if (!next_dc || next_dc->di.lstart > end)
di.len = end - di.lstart;
else
- di.len = next_dc->lstart - di.lstart;
+ di.len = next_dc->di.lstart - di.lstart;
di.start = start + di.lstart - lstart;
}

@@ -1333,7 +1423,7 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
__relocate_discard_cmd(dcc, prev_dc);
di = prev_dc->di;
tdc = prev_dc;
- merged = true;
+ goto next;
}

if (next_dc && next_dc->state == D_PREP &&
@@ -1347,13 +1437,10 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
__relocate_discard_cmd(dcc, next_dc);
if (tdc)
__remove_discard_cmd(sbi, tdc);
- merged = true;
+ goto next;
}

- if (!merged) {
- __insert_discard_tree(sbi, bdev, di.lstart, di.start,
- di.len, NULL, NULL);
- }
+ __insert_discard_cmd(sbi, bdev, di.lstart, di.start, di.len);
next:
prev_dc = next_dc;
if (!prev_dc)
@@ -1392,15 +1479,11 @@ static void __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
struct rb_node **insert_p = NULL, *insert_parent = NULL;
struct discard_cmd *dc;
struct blk_plug plug;
- unsigned int pos = dcc->next_pos;
bool io_interrupted = false;

mutex_lock(&dcc->cmd_lock);
- dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
- NULL, pos,
- (struct rb_entry **)&prev_dc,
- (struct rb_entry **)&next_dc,
- &insert_p, &insert_parent, true, NULL);
+ dc = __lookup_discard_cmd_ret(&dcc->root, dcc->next_pos,
+ &prev_dc, &next_dc, &insert_p, &insert_parent);
if (!dc)
dc = next_dc;

@@ -1418,7 +1501,7 @@ static void __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
break;
}

- dcc->next_pos = dc->lstart + dc->len;
+ dcc->next_pos = dc->di.lstart + dc->di.len;
err = __submit_discard_cmd(sbi, dpolicy, dc, issued);

if (*issued >= dpolicy->max_requests)
@@ -1477,8 +1560,7 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
if (list_empty(pend_list))
goto next;
if (unlikely(dcc->rbtree_check))
- f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
- &dcc->root));
+ f2fs_bug_on(sbi, !f2fs_check_discard_tree(sbi));
blk_start_plug(&plug);
list_for_each_entry_safe(dc, tmp, pend_list, list) {
f2fs_bug_on(sbi, dc->state != D_PREP);
@@ -1556,7 +1638,7 @@ static unsigned int __wait_one_discard_bio(struct f2fs_sb_info *sbi,
dc->ref--;
if (!dc->ref) {
if (!dc->error)
- len = dc->len;
+ len = dc->di.len;
__remove_discard_cmd(sbi, dc);
}
mutex_unlock(&dcc->cmd_lock);
@@ -1579,14 +1661,15 @@ static unsigned int __wait_discard_cmd_range(struct f2fs_sb_info *sbi,

mutex_lock(&dcc->cmd_lock);
list_for_each_entry_safe(iter, tmp, wait_list, list) {
- if (iter->lstart + iter->len <= start || end <= iter->lstart)
+ if (iter->di.lstart + iter->di.len <= start ||
+ end <= iter->di.lstart)
continue;
- if (iter->len < dpolicy->granularity)
+ if (iter->di.len < dpolicy->granularity)
continue;
if (iter->state == D_DONE && !iter->ref) {
wait_for_completion_io(&iter->wait);
if (!iter->error)
- trimmed += iter->len;
+ trimmed += iter->di.len;
__remove_discard_cmd(sbi, iter);
} else {
iter->ref++;
@@ -1630,8 +1713,7 @@ static void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
bool need_wait = false;

mutex_lock(&dcc->cmd_lock);
- dc = (struct discard_cmd *)f2fs_lookup_rb_tree(&dcc->root,
- NULL, blkaddr);
+ dc = __lookup_discard_cmd(sbi, blkaddr);
if (dc) {
if (dc->state == D_PREP) {
__punch_discard_cmd(sbi, dc, blkaddr);
@@ -2964,24 +3046,20 @@ static unsigned int __issue_discard_cmd_range(struct f2fs_sb_info *sbi,

mutex_lock(&dcc->cmd_lock);
if (unlikely(dcc->rbtree_check))
- f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
- &dcc->root));
-
- dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
- NULL, start,
- (struct rb_entry **)&prev_dc,
- (struct rb_entry **)&next_dc,
- &insert_p, &insert_parent, true, NULL);
+ f2fs_bug_on(sbi, !f2fs_check_discard_tree(sbi));
+
+ dc = __lookup_discard_cmd_ret(&dcc->root, start,
+ &prev_dc, &next_dc, &insert_p, &insert_parent);
if (!dc)
dc = next_dc;

blk_start_plug(&plug);

- while (dc && dc->lstart <= end) {
+ while (dc && dc->di.lstart <= end) {
struct rb_node *node;
int err = 0;

- if (dc->len < dpolicy->granularity)
+ if (dc->di.len < dpolicy->granularity)
goto skip;

if (dc->state != D_PREP) {
@@ -2992,7 +3070,7 @@ static unsigned int __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
err = __submit_discard_cmd(sbi, dpolicy, dc, &issued);

if (issued >= dpolicy->max_requests) {
- start = dc->lstart + dc->len;
+ start = dc->di.lstart + dc->di.len;

if (err)
__remove_discard_cmd(sbi, dc);
--
2.40.0.rc1.284.g88254d51c5-goog


2023-03-21 16:40:29

by patchwork-bot+f2fs

[permalink] [raw]
Subject: Re: [f2fs-dev] [PATCH 0/3] remove shared memory structures

Hello:

This series was applied to jaegeuk/f2fs.git (dev)
by Jaegeuk Kim <[email protected]>:

On Mon, 13 Mar 2023 13:12:13 -0700 you wrote:
> This series removes the use of rb_entry based on memory alignment which doesn't
> look like a right design when considering various architectures/compilers.
>
> v2 from v1:
> - adjusted Eric's review
> - refactored gc.c further to clean up
>
> [...]

Here is the summary with links:
- [f2fs-dev,1/3] f2fs: factor out victim_entry usage from general rb_tree use
https://git.kernel.org/jaegeuk/f2fs/c/e433c7887585
- [f2fs-dev,2/3] f2fs: factor out discard_cmd usage from general rb_tree use
https://git.kernel.org/jaegeuk/f2fs/c/7e9775a516ff
- [f2fs-dev,3/3] f2fs: remove entire rb_entry sharing
https://git.kernel.org/jaegeuk/f2fs/c/6b40bc364c10

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html



2023-03-23 14:24:00

by Chao Yu

[permalink] [raw]
Subject: Re: [f2fs-dev] [PATCH 1/3] f2fs: factor out victim_entry usage from general rb_tree use

On 2023/3/14 4:12, Jaegeuk Kim wrote:
> Let's reduce the complexity of mixed use of rb_tree in victim_entry from
> extent_cache and discard_cmd.
>
> This should fix arm32 memory alignment issue caused by shared rb_entry.
>
> [struct victim_entry] [struct rb_entry]
> [0] struct rb_node rb_node; [0] struct rb_node rb_node;
> union {
> struct {
> unsigned int ofs;
> unsigned int len;
> };
> [16] unsigned long long mtime; [12] unsigned long long key;
> } __packed;
>
> Cc: <[email protected]>
> Fixes: 093749e296e2 ("f2fs: support age threshold based garbage collection")
> Signed-off-by: Jaegeuk Kim <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,

2023-03-23 14:38:14

by Chao Yu

[permalink] [raw]
Subject: Re: [f2fs-dev] [PATCH 2/3] f2fs: factor out discard_cmd usage from general rb_tree use

On 2023/3/14 4:12, Jaegeuk Kim wrote:
> This is a second part to remove the mixed use of rb_tree in discard_cmd from
> extent_cache.
>
> This should also fix arm32 memory alignment issue caused by shared rb_entry.
>
> [struct discard_cmd] [struct rb_entry]
> [0] struct rb_node rb_node; [0] struct rb_node rb_node;
> union { union {
> struct { struct {
> [16] block_t lstart; [12] unsigned int ofs;
> block_t len; unsigned int len;
> };
> unsigned long long key;
> } __packed;
>
> Cc: <[email protected]>
> Fixes: 004b68621897 ("f2fs: use rb-tree to track pending discard commands")
> Signed-off-by: Jaegeuk Kim <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,

2023-03-23 14:38:22

by Chao Yu

[permalink] [raw]
Subject: Re: [f2fs-dev] [PATCH 3/3] f2fs: remove entire rb_entry sharing

On 2023/3/14 4:12, Jaegeuk Kim wrote:
> This is a last part to remove the memory sharing for rb_tree in extent_cache.
>
> This should also fix arm32 memory alignment issue.
>
> [struct extent_node] [struct rb_entry]
> [0] struct rb_node rb_node; [0] struct rb_node rb_node;
> union { union {
> struct { struct {
> [16] unsigned int fofs; [12] unsigned int ofs;
> unsigned int len; unsigned int len;
> };
> unsigned long long key;
> } __packed;
>
> Cc: <[email protected]>
> Fixes: 13054c548a1c ("f2fs: introduce infra macro and data structure of rb-tree extent cache")
> Signed-off-by: Jaegeuk Kim <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,

2023-03-24 17:02:29

by Jaegeuk Kim

[permalink] [raw]
Subject: Re: [PATCH 2/3 v2] f2fs: factor out discard_cmd usage from general rb_tree use

This is a second part to remove the mixed use of rb_tree in discard_cmd from
extent_cache.

This should also fix arm32 memory alignment issue caused by shared rb_entry.

[struct discard_cmd] [struct rb_entry]
[0] struct rb_node rb_node; [0] struct rb_node rb_node;
union { union {
struct { struct {
[16] block_t lstart; [12] unsigned int ofs;
block_t len; unsigned int len;
};
unsigned long long key;
} __packed;

Cc: <[email protected]>
Fixes: 004b68621897 ("f2fs: use rb-tree to track pending discard commands")
Signed-off-by: Jaegeuk Kim <[email protected]>
---

Change log from v1:
- fix a bug when spliting/merging discard commands

fs/f2fs/extent_cache.c | 36 +-----
fs/f2fs/f2fs.h | 23 +---
fs/f2fs/segment.c | 249 +++++++++++++++++++++++++++--------------
3 files changed, 169 insertions(+), 139 deletions(-)

diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c
index d1aa4609ca6b..5c206f941aac 100644
--- a/fs/f2fs/extent_cache.c
+++ b/fs/f2fs/extent_cache.c
@@ -192,7 +192,7 @@ static struct rb_entry *__lookup_rb_tree_slow(struct rb_root_cached *root,
return NULL;
}

-struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
+static struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
struct rb_entry *cached_re, unsigned int ofs)
{
struct rb_entry *re;
@@ -204,7 +204,7 @@ struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
return re;
}

-struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
+static struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
struct rb_root_cached *root,
struct rb_node **parent,
unsigned int ofs, bool *leftmost)
@@ -238,7 +238,7 @@ struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
* in order to simplify the insertion after.
* tree must stay unchanged between lookup and insertion.
*/
-struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
+static struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
struct rb_entry *cached_re,
unsigned int ofs,
struct rb_entry **prev_entry,
@@ -311,36 +311,6 @@ struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
return re;
}

-bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root)
-{
-#ifdef CONFIG_F2FS_CHECK_FS
- struct rb_node *cur = rb_first_cached(root), *next;
- struct rb_entry *cur_re, *next_re;
-
- if (!cur)
- return true;
-
- while (cur) {
- next = rb_next(cur);
- if (!next)
- return true;
-
- cur_re = rb_entry(cur, struct rb_entry, rb_node);
- next_re = rb_entry(next, struct rb_entry, rb_node);
-
- if (cur_re->ofs + cur_re->len > next_re->ofs) {
- f2fs_info(sbi, "inconsistent rbtree, cur(%u, %u) next(%u, %u)",
- cur_re->ofs, cur_re->len,
- next_re->ofs, next_re->len);
- return false;
- }
- cur = next;
- }
-#endif
- return true;
-}
-
static struct kmem_cache *extent_tree_slab;
static struct kmem_cache *extent_node_slab;

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 9396549e112d..6e04fea9c34f 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -353,15 +353,7 @@ struct discard_info {

struct discard_cmd {
struct rb_node rb_node; /* rb node located in rb-tree */
- union {
- struct {
- block_t lstart; /* logical start address */
- block_t len; /* length */
- block_t start; /* actual start address in dev */
- };
- struct discard_info di; /* discard info */
-
- };
+ struct discard_info di; /* discard info */
struct list_head list; /* command list */
struct completion wait; /* compleation */
struct block_device *bdev; /* bdev */
@@ -4132,19 +4124,6 @@ void f2fs_leave_shrinker(struct f2fs_sb_info *sbi);
* extent_cache.c
*/
bool sanity_check_extent_cache(struct inode *inode);
-struct rb_entry *f2fs_lookup_rb_tree(struct rb_root_cached *root,
- struct rb_entry *cached_re, unsigned int ofs);
-struct rb_node **f2fs_lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root,
- struct rb_node **parent,
- unsigned int ofs, bool *leftmost);
-struct rb_entry *f2fs_lookup_rb_tree_ret(struct rb_root_cached *root,
- struct rb_entry *cached_re, unsigned int ofs,
- struct rb_entry **prev_entry, struct rb_entry **next_entry,
- struct rb_node ***insert_p, struct rb_node **insert_parent,
- bool force, bool *leftmost);
-bool f2fs_check_rb_tree_consistence(struct f2fs_sb_info *sbi,
- struct rb_root_cached *root);
void f2fs_init_extent_tree(struct inode *inode);
void f2fs_drop_extent_tree(struct inode *inode);
void f2fs_destroy_extent_node(struct inode *inode);
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index e98a12e8dca1..d135046108ef 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -933,9 +933,9 @@ static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
dc = f2fs_kmem_cache_alloc(discard_cmd_slab, GFP_NOFS, true, NULL);
INIT_LIST_HEAD(&dc->list);
dc->bdev = bdev;
- dc->lstart = lstart;
- dc->start = start;
- dc->len = len;
+ dc->di.lstart = lstart;
+ dc->di.start = start;
+ dc->di.len = len;
dc->ref = 0;
dc->state = D_PREP;
dc->queued = 0;
@@ -950,20 +950,108 @@ static struct discard_cmd *__create_discard_cmd(struct f2fs_sb_info *sbi,
return dc;
}

-static struct discard_cmd *__attach_discard_cmd(struct f2fs_sb_info *sbi,
- struct block_device *bdev, block_t lstart,
- block_t start, block_t len,
- struct rb_node *parent, struct rb_node **p,
- bool leftmost)
+static bool f2fs_check_discard_tree(struct f2fs_sb_info *sbi)
+{
+#ifdef CONFIG_F2FS_CHECK_FS
+ struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
+ struct rb_node *cur = rb_first_cached(&dcc->root), *next;
+ struct discard_cmd *cur_dc, *next_dc;
+
+ while (cur) {
+ next = rb_next(cur);
+ if (!next)
+ return true;
+
+ cur_dc = rb_entry(cur, struct discard_cmd, rb_node);
+ next_dc = rb_entry(next, struct discard_cmd, rb_node);
+
+ if (cur_dc->di.lstart + cur_dc->di.len > next_dc->di.lstart) {
+ f2fs_info(sbi, "broken discard_rbtree, "
+ "cur(%u, %u) next(%u, %u)",
+ cur_dc->di.lstart, cur_dc->di.len,
+ next_dc->di.lstart, next_dc->di.len);
+ return false;
+ }
+ cur = next;
+ }
+#endif
+ return true;
+}
+
+static struct discard_cmd *__lookup_discard_cmd(struct f2fs_sb_info *sbi,
+ block_t blkaddr)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
+ struct rb_node *node = dcc->root.rb_root.rb_node;
struct discard_cmd *dc;

- dc = __create_discard_cmd(sbi, bdev, lstart, start, len);
+ while (node) {
+ dc = rb_entry(node, struct discard_cmd, rb_node);

- rb_link_node(&dc->rb_node, parent, p);
- rb_insert_color_cached(&dc->rb_node, &dcc->root, leftmost);
+ if (blkaddr < dc->di.lstart)
+ node = node->rb_left;
+ else if (blkaddr >= dc->di.lstart + dc->di.len)
+ node = node->rb_right;
+ else
+ return dc;
+ }
+ return NULL;
+}
+
+static struct discard_cmd *__lookup_discard_cmd_ret(struct rb_root_cached *root,
+ block_t blkaddr,
+ struct discard_cmd **prev_entry,
+ struct discard_cmd **next_entry,
+ struct rb_node ***insert_p,
+ struct rb_node **insert_parent)
+{
+ struct rb_node **pnode = &root->rb_root.rb_node;
+ struct rb_node *parent = NULL, *tmp_node;
+ struct discard_cmd *dc;
+
+ *insert_p = NULL;
+ *insert_parent = NULL;
+ *prev_entry = NULL;
+ *next_entry = NULL;
+
+ if (RB_EMPTY_ROOT(&root->rb_root))
+ return NULL;
+
+ while (*pnode) {
+ parent = *pnode;
+ dc = rb_entry(*pnode, struct discard_cmd, rb_node);
+
+ if (blkaddr < dc->di.lstart)
+ pnode = &(*pnode)->rb_left;
+ else if (blkaddr >= dc->di.lstart + dc->di.len)
+ pnode = &(*pnode)->rb_right;
+ else
+ goto lookup_neighbors;
+ }
+
+ *insert_p = pnode;
+ *insert_parent = parent;
+
+ dc = rb_entry(parent, struct discard_cmd, rb_node);
+ tmp_node = parent;
+ if (parent && blkaddr > dc->di.lstart)
+ tmp_node = rb_next(parent);
+ *next_entry = rb_entry_safe(tmp_node, struct discard_cmd, rb_node);
+
+ tmp_node = parent;
+ if (parent && blkaddr < dc->di.lstart)
+ tmp_node = rb_prev(parent);
+ *prev_entry = rb_entry_safe(tmp_node, struct discard_cmd, rb_node);
+ return NULL;
+
+lookup_neighbors:
+ /* lookup prev node for merging backward later */
+ tmp_node = rb_prev(&dc->rb_node);
+ *prev_entry = rb_entry_safe(tmp_node, struct discard_cmd, rb_node);

+ /* lookup next node for merging frontward later */
+ tmp_node = rb_next(&dc->rb_node);
+ *next_entry = rb_entry_safe(tmp_node, struct discard_cmd, rb_node);
return dc;
}

@@ -975,7 +1063,7 @@ static void __detach_discard_cmd(struct discard_cmd_control *dcc,

list_del(&dc->list);
rb_erase_cached(&dc->rb_node, &dcc->root);
- dcc->undiscard_blks -= dc->len;
+ dcc->undiscard_blks -= dc->di.len;

kmem_cache_free(discard_cmd_slab, dc);

@@ -988,7 +1076,7 @@ static void __remove_discard_cmd(struct f2fs_sb_info *sbi,
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
unsigned long flags;

- trace_f2fs_remove_discard(dc->bdev, dc->start, dc->len);
+ trace_f2fs_remove_discard(dc->bdev, dc->di.start, dc->di.len);

spin_lock_irqsave(&dc->lock, flags);
if (dc->bio_ref) {
@@ -1006,7 +1094,7 @@ static void __remove_discard_cmd(struct f2fs_sb_info *sbi,
printk_ratelimited(
"%sF2FS-fs (%s): Issue discard(%u, %u, %u) failed, ret: %d",
KERN_INFO, sbi->sb->s_id,
- dc->lstart, dc->start, dc->len, dc->error);
+ dc->di.lstart, dc->di.start, dc->di.len, dc->error);
__detach_discard_cmd(dcc, dc);
}

@@ -1122,14 +1210,14 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi,
if (is_sbi_flag_set(sbi, SBI_NEED_FSCK))
return 0;

- trace_f2fs_issue_discard(bdev, dc->start, dc->len);
+ trace_f2fs_issue_discard(bdev, dc->di.start, dc->di.len);

- lstart = dc->lstart;
- start = dc->start;
- len = dc->len;
+ lstart = dc->di.lstart;
+ start = dc->di.start;
+ len = dc->di.len;
total_len = len;

- dc->len = 0;
+ dc->di.len = 0;

while (total_len && *issued < dpolicy->max_requests && !err) {
struct bio *bio = NULL;
@@ -1145,7 +1233,7 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi,
if (*issued == dpolicy->max_requests)
last = true;

- dc->len += len;
+ dc->di.len += len;

if (time_to_inject(sbi, FAULT_DISCARD)) {
err = -EIO;
@@ -1207,34 +1295,41 @@ static int __submit_discard_cmd(struct f2fs_sb_info *sbi,
return err;
}

-static void __insert_discard_tree(struct f2fs_sb_info *sbi,
+static void __insert_discard_cmd(struct f2fs_sb_info *sbi,
struct block_device *bdev, block_t lstart,
- block_t start, block_t len,
- struct rb_node **insert_p,
- struct rb_node *insert_parent)
+ block_t start, block_t len)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
- struct rb_node **p;
+ struct rb_node **p = &dcc->root.rb_root.rb_node;
struct rb_node *parent = NULL;
+ struct discard_cmd *dc;
bool leftmost = true;

- if (insert_p && insert_parent) {
- parent = insert_parent;
- p = insert_p;
- goto do_insert;
+ /* look up rb tree to find parent node */
+ while (*p) {
+ parent = *p;
+ dc = rb_entry(parent, struct discard_cmd, rb_node);
+
+ if (lstart < dc->di.lstart) {
+ p = &(*p)->rb_left;
+ } else if (lstart >= dc->di.lstart + dc->di.len) {
+ p = &(*p)->rb_right;
+ leftmost = false;
+ } else {
+ f2fs_bug_on(sbi, 1);
+ }
}

- p = f2fs_lookup_rb_tree_for_insert(sbi, &dcc->root, &parent,
- lstart, &leftmost);
-do_insert:
- __attach_discard_cmd(sbi, bdev, lstart, start, len, parent,
- p, leftmost);
+ dc = __create_discard_cmd(sbi, bdev, lstart, start, len);
+
+ rb_link_node(&dc->rb_node, parent, p);
+ rb_insert_color_cached(&dc->rb_node, &dcc->root, leftmost);
}

static void __relocate_discard_cmd(struct discard_cmd_control *dcc,
struct discard_cmd *dc)
{
- list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->len)]);
+ list_move_tail(&dc->list, &dcc->pend_list[plist_idx(dc->di.len)]);
}

static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
@@ -1244,7 +1339,7 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
struct discard_info di = dc->di;
bool modified = false;

- if (dc->state == D_DONE || dc->len == 1) {
+ if (dc->state == D_DONE || dc->di.len == 1) {
__remove_discard_cmd(sbi, dc);
return;
}
@@ -1252,23 +1347,22 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
dcc->undiscard_blks -= di.len;

if (blkaddr > di.lstart) {
- dc->len = blkaddr - dc->lstart;
- dcc->undiscard_blks += dc->len;
+ dc->di.len = blkaddr - dc->di.lstart;
+ dcc->undiscard_blks += dc->di.len;
__relocate_discard_cmd(dcc, dc);
modified = true;
}

if (blkaddr < di.lstart + di.len - 1) {
if (modified) {
- __insert_discard_tree(sbi, dc->bdev, blkaddr + 1,
+ __insert_discard_cmd(sbi, dc->bdev, blkaddr + 1,
di.start + blkaddr + 1 - di.lstart,
- di.lstart + di.len - 1 - blkaddr,
- NULL, NULL);
+ di.lstart + di.len - 1 - blkaddr);
} else {
- dc->lstart++;
- dc->len--;
- dc->start++;
- dcc->undiscard_blks += dc->len;
+ dc->di.lstart++;
+ dc->di.len--;
+ dc->di.start++;
+ dcc->undiscard_blks += dc->di.len;
__relocate_discard_cmd(dcc, dc);
}
}
@@ -1287,17 +1381,14 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
SECTOR_TO_BLOCK(bdev_max_discard_sectors(bdev));
block_t end = lstart + len;

- dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
- NULL, lstart,
- (struct rb_entry **)&prev_dc,
- (struct rb_entry **)&next_dc,
- &insert_p, &insert_parent, true, NULL);
+ dc = __lookup_discard_cmd_ret(&dcc->root, lstart,
+ &prev_dc, &next_dc, &insert_p, &insert_parent);
if (dc)
prev_dc = dc;

if (!prev_dc) {
di.lstart = lstart;
- di.len = next_dc ? next_dc->lstart - lstart : len;
+ di.len = next_dc ? next_dc->di.lstart - lstart : len;
di.len = min(di.len, len);
di.start = start;
}
@@ -1308,16 +1399,16 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
struct discard_cmd *tdc = NULL;

if (prev_dc) {
- di.lstart = prev_dc->lstart + prev_dc->len;
+ di.lstart = prev_dc->di.lstart + prev_dc->di.len;
if (di.lstart < lstart)
di.lstart = lstart;
if (di.lstart >= end)
break;

- if (!next_dc || next_dc->lstart > end)
+ if (!next_dc || next_dc->di.lstart > end)
di.len = end - di.lstart;
else
- di.len = next_dc->lstart - di.lstart;
+ di.len = next_dc->di.lstart - di.lstart;
di.start = start + di.lstart - lstart;
}

@@ -1350,10 +1441,9 @@ static void __update_discard_tree_range(struct f2fs_sb_info *sbi,
merged = true;
}

- if (!merged) {
- __insert_discard_tree(sbi, bdev, di.lstart, di.start,
- di.len, NULL, NULL);
- }
+ if (!merged)
+ __insert_discard_cmd(sbi, bdev,
+ di.lstart, di.start, di.len);
next:
prev_dc = next_dc;
if (!prev_dc)
@@ -1392,15 +1482,11 @@ static void __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
struct rb_node **insert_p = NULL, *insert_parent = NULL;
struct discard_cmd *dc;
struct blk_plug plug;
- unsigned int pos = dcc->next_pos;
bool io_interrupted = false;

mutex_lock(&dcc->cmd_lock);
- dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
- NULL, pos,
- (struct rb_entry **)&prev_dc,
- (struct rb_entry **)&next_dc,
- &insert_p, &insert_parent, true, NULL);
+ dc = __lookup_discard_cmd_ret(&dcc->root, dcc->next_pos,
+ &prev_dc, &next_dc, &insert_p, &insert_parent);
if (!dc)
dc = next_dc;

@@ -1418,7 +1504,7 @@ static void __issue_discard_cmd_orderly(struct f2fs_sb_info *sbi,
break;
}

- dcc->next_pos = dc->lstart + dc->len;
+ dcc->next_pos = dc->di.lstart + dc->di.len;
err = __submit_discard_cmd(sbi, dpolicy, dc, issued);

if (*issued >= dpolicy->max_requests)
@@ -1477,8 +1563,7 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
if (list_empty(pend_list))
goto next;
if (unlikely(dcc->rbtree_check))
- f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
- &dcc->root));
+ f2fs_bug_on(sbi, !f2fs_check_discard_tree(sbi));
blk_start_plug(&plug);
list_for_each_entry_safe(dc, tmp, pend_list, list) {
f2fs_bug_on(sbi, dc->state != D_PREP);
@@ -1556,7 +1641,7 @@ static unsigned int __wait_one_discard_bio(struct f2fs_sb_info *sbi,
dc->ref--;
if (!dc->ref) {
if (!dc->error)
- len = dc->len;
+ len = dc->di.len;
__remove_discard_cmd(sbi, dc);
}
mutex_unlock(&dcc->cmd_lock);
@@ -1579,14 +1664,15 @@ static unsigned int __wait_discard_cmd_range(struct f2fs_sb_info *sbi,

mutex_lock(&dcc->cmd_lock);
list_for_each_entry_safe(iter, tmp, wait_list, list) {
- if (iter->lstart + iter->len <= start || end <= iter->lstart)
+ if (iter->di.lstart + iter->di.len <= start ||
+ end <= iter->di.lstart)
continue;
- if (iter->len < dpolicy->granularity)
+ if (iter->di.len < dpolicy->granularity)
continue;
if (iter->state == D_DONE && !iter->ref) {
wait_for_completion_io(&iter->wait);
if (!iter->error)
- trimmed += iter->len;
+ trimmed += iter->di.len;
__remove_discard_cmd(sbi, iter);
} else {
iter->ref++;
@@ -1630,8 +1716,7 @@ static void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
bool need_wait = false;

mutex_lock(&dcc->cmd_lock);
- dc = (struct discard_cmd *)f2fs_lookup_rb_tree(&dcc->root,
- NULL, blkaddr);
+ dc = __lookup_discard_cmd(sbi, blkaddr);
if (dc) {
if (dc->state == D_PREP) {
__punch_discard_cmd(sbi, dc, blkaddr);
@@ -2964,24 +3049,20 @@ static unsigned int __issue_discard_cmd_range(struct f2fs_sb_info *sbi,

mutex_lock(&dcc->cmd_lock);
if (unlikely(dcc->rbtree_check))
- f2fs_bug_on(sbi, !f2fs_check_rb_tree_consistence(sbi,
- &dcc->root));
-
- dc = (struct discard_cmd *)f2fs_lookup_rb_tree_ret(&dcc->root,
- NULL, start,
- (struct rb_entry **)&prev_dc,
- (struct rb_entry **)&next_dc,
- &insert_p, &insert_parent, true, NULL);
+ f2fs_bug_on(sbi, !f2fs_check_discard_tree(sbi));
+
+ dc = __lookup_discard_cmd_ret(&dcc->root, start,
+ &prev_dc, &next_dc, &insert_p, &insert_parent);
if (!dc)
dc = next_dc;

blk_start_plug(&plug);

- while (dc && dc->lstart <= end) {
+ while (dc && dc->di.lstart <= end) {
struct rb_node *node;
int err = 0;

- if (dc->len < dpolicy->granularity)
+ if (dc->di.len < dpolicy->granularity)
goto skip;

if (dc->state != D_PREP) {
@@ -2992,7 +3073,7 @@ static unsigned int __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
err = __submit_discard_cmd(sbi, dpolicy, dc, &issued);

if (issued >= dpolicy->max_requests) {
- start = dc->lstart + dc->len;
+ start = dc->di.lstart + dc->di.len;

if (err)
__remove_discard_cmd(sbi, dc);
--
2.40.0.348.gf938b09366-goog

2023-03-26 04:12:42

by Chao Yu

[permalink] [raw]
Subject: Re: [f2fs-dev] [PATCH 2/3 v2] f2fs: factor out discard_cmd usage from general rb_tree use

On 2023/3/25 0:57, Jaegeuk Kim wrote:
> This is a second part to remove the mixed use of rb_tree in discard_cmd from
> extent_cache.
>
> This should also fix arm32 memory alignment issue caused by shared rb_entry.
>
> [struct discard_cmd] [struct rb_entry]
> [0] struct rb_node rb_node; [0] struct rb_node rb_node;
> union { union {
> struct { struct {
> [16] block_t lstart; [12] unsigned int ofs;
> block_t len; unsigned int len;
> };
> unsigned long long key;
> } __packed;
>
> Cc: <[email protected]>
> Fixes: 004b68621897 ("f2fs: use rb-tree to track pending discard commands")
> Signed-off-by: Jaegeuk Kim <[email protected]>

Reviewed-by: Chao Yu <[email protected]>

Thanks,