From 1b84ddb5c9f8f4f1654feb50b4086fdcd9be7597 Mon Sep 17 00:00:00 2001 From: Luke Shumaker Date: Sat, 4 Feb 2023 00:17:49 -0700 Subject: btrfs: Use a byte pool when computing checksums --- lib/btrfs/csums.go | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/lib/btrfs/csums.go b/lib/btrfs/csums.go index 2bfa588..9e0b755 100644 --- a/lib/btrfs/csums.go +++ b/lib/btrfs/csums.go @@ -12,23 +12,31 @@ import ( "git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfssum" "git.lukeshu.com/btrfs-progs-ng/lib/btrfs/btrfstree" "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" ) +// dat doesn't escape to the heap in .ReadAt(dat, …), but the compiler +// can't figure that out, so we use a Pool for our byte arrays, since +// the compiler won't let us allocate them on the stack. +var blockPool containers.SlicePool[byte] + func ChecksumLogical(fs diskio.File[btrfsvol.LogicalAddr], alg btrfssum.CSumType, laddr btrfsvol.LogicalAddr) (btrfssum.CSum, error) { - var dat [btrfssum.BlockSize]byte - if _, err := fs.ReadAt(dat[:], laddr); err != nil { + dat := blockPool.Get(btrfssum.BlockSize) + defer blockPool.Put(dat) + if _, err := fs.ReadAt(dat, laddr); err != nil { return btrfssum.CSum{}, err } - return alg.Sum(dat[:]) + return alg.Sum(dat) } func ChecksumPhysical(dev *Device, alg btrfssum.CSumType, paddr btrfsvol.PhysicalAddr) (btrfssum.CSum, error) { - var dat [btrfssum.BlockSize]byte - if _, err := dev.ReadAt(dat[:], paddr); err != nil { + dat := blockPool.Get(btrfssum.BlockSize) + defer blockPool.Put(dat) + if _, err := dev.ReadAt(dat, paddr); err != nil { return btrfssum.CSum{}, err } - return alg.Sum(dat[:]) + return alg.Sum(dat) } func ChecksumQualifiedPhysical(fs *FS, alg btrfssum.CSumType, paddr btrfsvol.QualifiedPhysicalAddr) (btrfssum.CSum, error) { -- cgit v1.2.3-2-g168b