76 lines
2.2 KiB
Diff
76 lines
2.2 KiB
Diff
From 86d6153417ddaccbe3d1f4466a374716006581f4 Mon Sep 17 00:00:00 2001
|
|
From: Theodore Ts'o <tytso@mit.edu>
|
|
Date: Sat, 25 Apr 2020 11:41:24 -0400
|
|
Subject: [PATCH] libext2fs: batch calls to ext2fs_zero_blocks2()
|
|
|
|
When allocating blocks for an indirect block mapped file, accumulate
|
|
blocks to be zero'ed and then call ext2fs_zero_blocks2() to zero them
|
|
in large chunks instead of block by block.
|
|
|
|
This significantly speeds up mkfs.ext3 since we don't send a large
|
|
number of ZERO_RANGE requests to the kernel, and while the kernel does
|
|
batch write requests, it is not batching ZERO_RANGE requests. It's
|
|
more efficient to batch in userspace in any case, since it avoids
|
|
unnecessary system calls.
|
|
|
|
Reported-by: Mario Schuknecht <mario.schuknecht@dresearch-fe.de>
|
|
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
|
|
---
|
|
lib/ext2fs/fallocate.c | 28 +++++++++++++++++++++++-----
|
|
1 file changed, 23 insertions(+), 5 deletions(-)
|
|
|
|
diff --git a/lib/ext2fs/fallocate.c b/lib/ext2fs/fallocate.c
|
|
index 31e47f8d..5cde7d5c 100644
|
|
--- a/lib/ext2fs/fallocate.c
|
|
+++ b/lib/ext2fs/fallocate.c
|
|
@@ -805,7 +805,8 @@ errcode_t ext2fs_fallocate(ext2_filsys fs, int flags, ext2_ino_t ino,
|
|
blk64_t start, blk64_t len)
|
|
{
|
|
struct ext2_inode inode_buf;
|
|
- blk64_t blk, x;
|
|
+ blk64_t blk, x, zero_blk, last = 0;
|
|
+ int zero_len = 0;
|
|
errcode_t err;
|
|
|
|
if (((flags & EXT2_FALLOCATE_FORCE_INIT) &&
|
|
@@ -841,15 +842,32 @@ errcode_t ext2fs_fallocate(ext2_filsys fs, int flags, ext2_ino_t ino,
|
|
if (x)
|
|
continue;
|
|
|
|
- err = ext2fs_bmap2(fs, ino, inode, NULL,
|
|
- BMAP_ALLOC | BMAP_UNINIT | BMAP_ZERO, blk,
|
|
- 0, &x);
|
|
+ err = ext2fs_bmap2(fs, ino, inode, NULL, BMAP_ALLOC,
|
|
+ blk, 0, &x);
|
|
if (err)
|
|
- return err;
|
|
+ goto errout;
|
|
+ if ((zero_len && (x != last+1)) ||
|
|
+ (zero_len >= 65536)) {
|
|
+ err = ext2fs_zero_blocks2(fs, zero_blk, zero_len,
|
|
+ NULL, NULL);
|
|
+ zero_len = 0;
|
|
+ if (err)
|
|
+ goto errout;
|
|
+ }
|
|
+ if (zero_len == 0) {
|
|
+ zero_blk = x;
|
|
+ zero_len = 1;
|
|
+ } else {
|
|
+ zero_len++;
|
|
+ }
|
|
+ last = x;
|
|
}
|
|
|
|
out:
|
|
if (inode == &inode_buf)
|
|
ext2fs_write_inode(fs, ino, inode);
|
|
+errout:
|
|
+ if (zero_len)
|
|
+ ext2fs_zero_blocks2(fs, zero_blk, zero_len, NULL, NULL);
|
|
return err;
|
|
}
|
|
--
|
|
2.23.0
|
|
|