tree-wide: Annotate values that I might want to be tuning

13 files changed, 61 insertions, 55 deletions

diff --git a/lib/btrfs/io4_fs.go b/lib/btrfs/io4_fs.go
index 3848ef1..41df3a8 100644
--- a/lib/btrfs/io4_fs.go
+++ b/lib/btrfs/io4_fs.go
@@ -22,6 +22,7 @@ import (
 	"git.lukeshu.com/btrfs-progs-ng/lib/containers"
 	"git.lukeshu.com/btrfs-progs-ng/lib/maps"
 	"git.lukeshu.com/btrfs-progs-ng/lib/slices"
+	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
 )
 
 type BareInode struct {
@@ -69,32 +70,37 @@ type Subvolume struct {
 	TreeID      btrfsprim.ObjID
 	NoChecksums bool
 
-	rootOnce sync.Once
-	rootVal  btrfsitem.Root
-	rootErr  error
+	initOnce sync.Once
 
-	bareInodeCache containers.LRUCache[btrfsprim.ObjID, *BareInode]
-	fullInodeCache containers.LRUCache[btrfsprim.ObjID, *FullInode]
-	dirCache       containers.LRUCache[btrfsprim.ObjID, *Dir]
-	fileCache      containers.LRUCache[btrfsprim.ObjID, *File]
+	rootVal btrfsitem.Root
+	rootErr error
+
+	bareInodeCache *containers.LRUCache[btrfsprim.ObjID, *BareInode]
+	fullInodeCache *containers.LRUCache[btrfsprim.ObjID, *FullInode]
+	dirCache       *containers.LRUCache[btrfsprim.ObjID, *Dir]
+	fileCache      *containers.LRUCache[btrfsprim.ObjID, *File]
 }
 
 func (sv *Subvolume) init() {
-	sv.rootOnce.Do(func() {
+	sv.initOnce.Do(func() {
 		root, err := sv.FS.TreeSearch(btrfsprim.ROOT_TREE_OBJECTID, btrfstree.RootItemSearchFn(sv.TreeID))
 		if err != nil {
 			sv.rootErr = err
-			return
+		} else {
+			switch rootBody := root.Body.(type) {
+			case btrfsitem.Root:
+				sv.rootVal = rootBody
+			case btrfsitem.Error:
+				sv.rootErr = fmt.Errorf("FS_TREE ROOT_ITEM has malformed body: %w", rootBody.Err)
+			default:
+				panic(fmt.Errorf("should not happen: ROOT_ITEM has unexpected item type: %T", rootBody))
+			}
 		}
 
-		switch rootBody := root.Body.(type) {
-		case btrfsitem.Root:
-			sv.rootVal = rootBody
-		case btrfsitem.Error:
-			sv.rootErr = fmt.Errorf("FS_TREE ROOT_ITEM has malformed body: %w", rootBody.Err)
-		default:
-			panic(fmt.Errorf("should not happen: ROOT_ITEM has unexpected item type: %T", rootBody))
-		}
+		sv.bareInodeCache = containers.NewLRUCache[btrfsprim.ObjID, *BareInode](textui.Tunable(128))
+		sv.fullInodeCache = containers.NewLRUCache[btrfsprim.ObjID, *FullInode](textui.Tunable(128))
+		sv.dirCache = containers.NewLRUCache[btrfsprim.ObjID, *Dir](textui.Tunable(128))
+		sv.fileCache = containers.NewLRUCache[btrfsprim.ObjID, *File](textui.Tunable(128))
 	})
 }
 
@@ -104,6 +110,7 @@ func (sv *Subvolume) GetRootInode() (btrfsprim.ObjID, error) {
 }
 
 func (sv *Subvolume) LoadBareInode(inode btrfsprim.ObjID) (*BareInode, error) {
+	sv.init()
 	val := sv.bareInodeCache.GetOrElse(inode, func() (val *BareInode) {
 		val = &BareInode{
 			Inode: inode,
@@ -136,6 +143,7 @@ func (sv *Subvolume) LoadBareInode(inode btrfsprim.ObjID) (*BareInode, error) {
 }
 
 func (sv *Subvolume) LoadFullInode(inode btrfsprim.ObjID) (*FullInode, error) {
+	sv.init()
 	val := sv.fullInodeCache.GetOrElse(inode, func() (val *FullInode) {
 		val = &FullInode{
 			BareInode: BareInode{
@@ -191,6 +199,7 @@ func (sv *Subvolume) LoadFullInode(inode btrfsprim.ObjID) (*FullInode, error) {
 }
 
 func (sv *Subvolume) LoadDir(inode btrfsprim.ObjID) (*Dir, error) {
+	sv.init()
 	val := sv.dirCache.GetOrElse(inode, func() (val *Dir) {
 		val = new(Dir)
 		fullInode, err := sv.LoadFullInode(inode)
@@ -326,6 +335,7 @@ func (dir *Dir) AbsPath() (string, error) {
 }
 
 func (sv *Subvolume) LoadFile(inode btrfsprim.ObjID) (*File, error) {
+	sv.init()
 	val := sv.fileCache.GetOrElse(inode, func() (val *File) {
 		val = new(File)
 		fullInode, err := sv.LoadFullInode(inode)
diff --git a/lib/btrfsprogs/btrfsinspect/rebuildmappings/fuzzymatchsums.go b/lib/btrfsprogs/btrfsinspect/rebuildmappings/fuzzymatchsums.go
index b1be7ba..a8d05eb 100644
--- a/lib/btrfsprogs/btrfsinspect/rebuildmappings/fuzzymatchsums.go
+++ b/lib/btrfsprogs/btrfsinspect/rebuildmappings/fuzzymatchsums.go
@@ -19,7 +19,7 @@ import (
 	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
 )
 
-const minFuzzyPct = 0.5
+var minFuzzyPct = textui.Tunable(0.5)
 
 type fuzzyRecord struct {
 	PAddr btrfsvol.QualifiedPhysicalAddr
diff --git a/lib/btrfsprogs/btrfsinspect/rebuildnodes/btrees/rebuilt_btrees.go b/lib/btrfsprogs/btrfsinspect/rebuildnodes/btrees/rebuilt_btrees.go
index 33eb352..5e8883a 100644
--- a/lib/btrfsprogs/btrfsinspect/rebuildnodes/btrees/rebuilt_btrees.go
+++ b/lib/btrfsprogs/btrfsinspect/rebuildnodes/btrees/rebuilt_btrees.go
@@ -1,4 +1,4 @@
-// Copyright (C) 2022  Luke Shumaker <lukeshu@lukeshu.com>
+// Copyright (C) 2022-2023  Luke Shumaker <lukeshu@lukeshu.com>
 //
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -191,7 +191,7 @@ func (ts *RebuiltTrees) AddRoot(ctx context.Context, treeID btrfsprim.ObjID, roo
 
 	var stats rootStats
 	stats.Leafs.D = len(tree.leafToRoots)
-	progressWriter := textui.NewProgress[rootStats](ctx, dlog.LogLevelInfo, 1*time.Second)
+	progressWriter := textui.NewProgress[rootStats](ctx, dlog.LogLevelInfo, textui.Tunable(1*time.Second))
 	for i, leaf := range maps.SortedKeys(tree.leafToRoots) {
 		stats.Leafs.N = i
 		progressWriter.Set(stats)
@@ -297,7 +297,7 @@ func (tree *rebuiltTree) indexLeafs(ctx context.Context, graph pkggraph.Graph) {
 
 	var stats textui.Portion[int]
 	stats.D = len(graph.Nodes)
-	progressWriter := textui.NewProgress[textui.Portion[int]](ctx, dlog.LogLevelInfo, 1*time.Second)
+	progressWriter := textui.NewProgress[textui.Portion[int]](ctx, dlog.LogLevelInfo, textui.Tunable(1*time.Second))
 	progress := func() {
 		stats.N = len(nodeToRoots)
 		progressWriter.Set(stats)
diff --git a/lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/graph.go b/lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/graph.go
index c4ed675..cf86d74 100644
--- a/lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/graph.go
+++ b/lib/btrfsprogs/btrfsinspect/rebuildnodes/graph/graph.go
@@ -197,7 +197,7 @@ func (g Graph) FinalCheck(ctx context.Context, fs diskio.File[btrfsvol.LogicalAd
 
 	ctx = dlog.WithField(_ctx, "btrfsinspect.rebuild-nodes.read.substep", "check-keypointers")
 	dlog.Info(_ctx, "Checking keypointers for dead-ends...")
-	progressWriter := textui.NewProgress[textui.Portion[int]](ctx, dlog.LogLevelInfo, 1*time.Second)
+	progressWriter := textui.NewProgress[textui.Portion[int]](ctx, dlog.LogLevelInfo, textui.Tunable(1*time.Second))
 	stats.D = len(g.EdgesTo)
 	progressWriter.Set(stats)
 	for laddr := range g.EdgesTo {
@@ -221,7 +221,7 @@ func (g Graph) FinalCheck(ctx context.Context, fs diskio.File[btrfsvol.LogicalAd
 	dlog.Info(_ctx, "Checking for btree loops...")
 	stats.D = len(g.Nodes)
 	stats.N = 0
-	progressWriter = textui.NewProgress[textui.Portion[int]](ctx, dlog.LogLevelInfo, 1*time.Second)
+	progressWriter = textui.NewProgress[textui.Portion[int]](ctx, dlog.LogLevelInfo, textui.Tunable(1*time.Second))
 	progressWriter.Set(stats)
 	visited := make(containers.Set[btrfsvol.LogicalAddr], len(g.Nodes))
 	numLoops := 0
diff --git a/lib/btrfsprogs/btrfsinspect/rebuildnodes/keyio/keyio.go b/lib/btrfsprogs/btrfsinspect/rebuildnodes/keyio/keyio.go
index b1e68f9..24c3dcf 100644
--- a/lib/btrfsprogs/btrfsinspect/rebuildnodes/keyio/keyio.go
+++ b/lib/btrfsprogs/btrfsinspect/rebuildnodes/keyio/keyio.go
@@ -17,6 +17,7 @@ import (
 	"git.lukeshu.com/btrfs-progs-ng/lib/btrfsprogs/btrfsinspect/rebuildnodes/graph"
 	"git.lukeshu.com/btrfs-progs-ng/lib/containers"
 	"git.lukeshu.com/btrfs-progs-ng/lib/diskio"
+	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
 )
 
 type ItemPtr struct {
@@ -50,7 +51,7 @@ func NewHandle(file diskio.File[btrfsvol.LogicalAddr], sb btrfstree.Superblock)
 
 		Sizes: make(map[ItemPtr]SizeAndErr),
 
-		cache: containers.NewLRUCache[btrfsvol.LogicalAddr, *diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node]](8),
+		cache: containers.NewLRUCache[btrfsvol.LogicalAddr, *diskio.Ref[btrfsvol.LogicalAddr, btrfstree.Node]](textui.Tunable(8)),
 	}
 }
 
diff --git a/lib/btrfsprogs/btrfsinspect/rebuildnodes/rebuild.go b/lib/btrfsprogs/btrfsinspect/rebuildnodes/rebuild.go
index 5d0804c..0a3ccdf 100644
--- a/lib/btrfsprogs/btrfsinspect/rebuildnodes/rebuild.go
+++ b/lib/btrfsprogs/btrfsinspect/rebuildnodes/rebuild.go
@@ -126,7 +126,7 @@ func (o *rebuilder) rebuild(_ctx context.Context) error {
 		o.itemQueue = nil
 		var progress textui.Portion[int]
 		progress.D = len(itemQueue)
-		progressWriter := textui.NewProgress[textui.Portion[int]](stepCtx, dlog.LogLevelInfo, 1*time.Second)
+		progressWriter := textui.NewProgress[textui.Portion[int]](stepCtx, dlog.LogLevelInfo, textui.Tunable(1*time.Second))
 		stepCtx = dlog.WithField(stepCtx, "btrfsinspect.rebuild-nodes.rebuild.substep.progress", &progress)
 		for i, key := range itemQueue {
 			itemCtx := dlog.WithField(stepCtx, "btrfsinspect.rebuild-nodes.rebuild.process.item", key)
@@ -160,7 +160,7 @@ func (o *rebuilder) rebuild(_ctx context.Context) error {
 			progress.D += len(resolvedAugments[treeID])
 		}
 		o.augmentQueue = make(map[btrfsprim.ObjID][]map[btrfsvol.LogicalAddr]int)
-		progressWriter = textui.NewProgress[textui.Portion[int]](stepCtx, dlog.LogLevelInfo, 1*time.Second)
+		progressWriter = textui.NewProgress[textui.Portion[int]](stepCtx, dlog.LogLevelInfo, textui.Tunable(1*time.Second))
 		stepCtx = dlog.WithField(stepCtx, "btrfsinspect.rebuild-nodes.rebuild.substep.progress", &progress)
 		for _, treeID := range maps.SortedKeys(resolvedAugments) {
 			treeCtx := dlog.WithField(stepCtx, "btrfsinspect.rebuild-nodes.rebuild.augment.tree", treeID)
diff --git a/lib/btrfsprogs/btrfsinspect/rebuildnodes/scan.go b/lib/btrfsprogs/btrfsinspect/rebuildnodes/scan.go
index 7a112b4..7e96e29 100644
--- a/lib/btrfsprogs/btrfsinspect/rebuildnodes/scan.go
+++ b/lib/btrfsprogs/btrfsinspect/rebuildnodes/scan.go
@@ -32,7 +32,7 @@ func ScanDevices(ctx context.Context, fs *btrfs.FS, scanResults btrfsinspect.Sca
 	stats.D = countNodes(scanResults)
 	progressWriter := textui.NewProgress[textui.Portion[int]](
 		dlog.WithField(ctx, "btrfsinspect.rebuild-nodes.read.substep", "read-nodes"),
-		dlog.LogLevelInfo, 1*time.Second)
+		dlog.LogLevelInfo, textui.Tunable(1*time.Second))
 
 	nodeGraph := graph.New(*sb)
 	keyIO := keyio.NewHandle(fs, *sb)
diff --git a/lib/btrfsprogs/btrfsinspect/scandevices.go b/lib/btrfsprogs/btrfsinspect/scandevices.go
index 4058663..7668a83 100644
--- a/lib/btrfsprogs/btrfsinspect/scandevices.go
+++ b/lib/btrfsprogs/btrfsinspect/scandevices.go
@@ -126,7 +126,7 @@ func ScanOneDevice(ctx context.Context, dev *btrfs.Device, sb btrfstree.Superblo
 	var sums strings.Builder
 	sums.Grow(numSums * csumSize)
 
-	progressWriter := textui.NewProgress[scanStats](ctx, dlog.LogLevelInfo, 1*time.Second)
+	progressWriter := textui.NewProgress[scanStats](ctx, dlog.LogLevelInfo, textui.Tunable(1*time.Second))
 	progress := func(pos btrfsvol.PhysicalAddr) {
 		progressWriter.Set(scanStats{
 			Portion: textui.Portion[btrfsvol.PhysicalAddr]{
diff --git a/lib/btrfsprogs/btrfsutil/open.go b/lib/btrfsprogs/btrfsutil/open.go
index 9491a20..441d4e2 100644
--- a/lib/btrfsprogs/btrfsutil/open.go
+++ b/lib/btrfsprogs/btrfsutil/open.go
@@ -14,6 +14,7 @@ import (
 	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs"
 	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol"
 	"git.lukeshu.com/btrfs-progs-ng/lib/diskio"
+	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
 )
 
 func Open(ctx context.Context, flag int, filenames ...string) (*btrfs.FS, error) {
@@ -30,8 +31,8 @@ func Open(ctx context.Context, flag int, filenames ...string) (*btrfs.FS, error)
 		}
 		bufFile := diskio.NewBufferedFile[btrfsvol.PhysicalAddr](
 			typedFile,
-			16384, // block size: 16KiB
-			1024,  // number of blocks to buffer; total of 16MiB
+			textui.Tunable[btrfsvol.PhysicalAddr](16384), // block size: 16KiB
+			textui.Tunable(1024),                         // number of blocks to buffer; total of 16MiB
 		)
 		devFile := &btrfs.Device{
 			File: bufFile,
diff --git a/lib/btrfsprogs/btrfsutil/skinny_paths.go b/lib/btrfsprogs/btrfsutil/skinny_paths.go
index 2f71968..6a51739 100644
--- a/lib/btrfsprogs/btrfsutil/skinny_paths.go
+++ b/lib/btrfsprogs/btrfsutil/skinny_paths.go
@@ -11,6 +11,7 @@ import (
 	"git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfsvol"
 	"git.lukeshu.com/btrfs-progs-ng/lib/containers"
 	"git.lukeshu.com/btrfs-progs-ng/lib/diskio"
+	"git.lukeshu.com/btrfs-progs-ng/lib/textui"
 )
 
 type skinnyItem struct {
@@ -42,7 +43,7 @@ func (a *SkinnyPathArena) init() {
 		// which is a good number for me.  Then I tought it to do a
 		// better job of recovering trees, and so the memory grew, and I
 		// cut it to 64K.  Then to 8K.  Then grew it to 128K.
-		a.fatItems = containers.NewLRUCache[skinnyItem, btrfstree.TreePathElem](128 * 1024)
+		a.fatItems = containers.NewLRUCache[skinnyItem, btrfstree.TreePathElem](textui.Tunable(128 * 1024))
 	}
 }
 
diff --git a/lib/containers/lru.go b/lib/containers/lru.go
index bfda361..aa372ed 100644
--- a/lib/containers/lru.go
+++ b/lib/containers/lru.go
@@ -5,45 +5,30 @@
 package containers
 
 import (
-	"sync"
-
 	lru "github.com/hashicorp/golang-lru"
 )
 
 // LRUCache is a least-recently-used(ish) cache.  A zero LRUCache is
-// usable and has a cache size of 128 items; use NewLRUCache to set a
-// different size.
+// not usable; it must be initialized with NewLRUCache.
 type LRUCache[K comparable, V any] struct {
-	initOnce sync.Once
-	inner    *lru.ARCCache
+	inner *lru.ARCCache
 }
 
 func NewLRUCache[K comparable, V any](size int) *LRUCache[K, V] {
 	c := new(LRUCache[K, V])
-	c.initOnce.Do(func() {
-		c.inner, _ = lru.NewARC(size)
-	})
+	c.inner, _ = lru.NewARC(size)
 	return c
 }
 
-func (c *LRUCache[K, V]) init() {
-	c.initOnce.Do(func() {
-		c.inner, _ = lru.NewARC(128)
-	})
-}
-
 func (c *LRUCache[K, V]) Add(key K, value V) {
-	c.init()
 	c.inner.Add(key, value)
 }
 
 func (c *LRUCache[K, V]) Contains(key K) bool {
-	c.init()
 	return c.inner.Contains(key)
 }
 
 func (c *LRUCache[K, V]) Get(key K) (value V, ok bool) {
-	c.init()
 	_value, ok := c.inner.Get(key)
 	if ok {
 		//nolint:forcetypeassert // Typed wrapper around untyped lib.
@@ -53,7 +38,6 @@ func (c *LRUCache[K, V]) Get(key K) (value V, ok bool) {
 }
 
 func (c *LRUCache[K, V]) Keys() []K {
-	c.init()
 	untyped := c.inner.Keys()
 	typed := make([]K, len(untyped))
 	for i := range untyped {
@@ -64,12 +48,10 @@ func (c *LRUCache[K, V]) Keys() []K {
 }
 
 func (c *LRUCache[K, V]) Len() int {
-	c.init()
 	return c.inner.Len()
 }
 
 func (c *LRUCache[K, V]) Peek(key K) (value V, ok bool) {
-	c.init()
 	_value, ok := c.inner.Peek(key)
 	if ok {
 		//nolint:forcetypeassert // Typed wrapper around untyped lib.
@@ -79,12 +61,10 @@ func (c *LRUCache[K, V]) Peek(key K) (value V, ok bool) {
 }
 
 func (c *LRUCache[K, V]) Purge() {
-	c.init()
 	c.inner.Purge()
 }
 
 func (c *LRUCache[K, V]) Remove(key K) {
-	c.init()
 	c.inner.Remove(key)
 }
 
diff --git a/lib/textui/log_memstats.go b/lib/textui/log_memstats.go
index 39733c6..6e3c3a1 100644
--- a/lib/textui/log_memstats.go
+++ b/lib/textui/log_memstats.go
@@ -19,7 +19,7 @@ type LiveMemUse struct {
 
 var _ fmt.Stringer = (*LiveMemUse)(nil)
 
-const liveMemUseUpdateInterval = 1 * time.Second
+var liveMemUseUpdateInterval = Tunable(1 * time.Second)
 
 func (o *LiveMemUse) String() string {
 	o.mu.Lock()
diff --git a/lib/textui/tunable.go b/lib/textui/tunable.go
new file mode 100644
index 0000000..7e5f311
--- /dev/null
+++ b/lib/textui/tunable.go
@@ -0,0 +1,13 @@
+// Copyright (C) 2022  Luke Shumaker <lukeshu@lukeshu.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+package textui
+
+// Tunable annotates a value as something that might want to be tuned
+// as the program gets optimized.
+//
+// TODO(lukeshu): Have Tunable be runtime-configurable.
+func Tunable[T any](x T) T {
+	return x
+}