[PATCH 9/9] xfs_mdrestore: fix missed progress reporting

Darrick J. Wong
2023-11-22T23:07:42Z

From: Darrick J. Wong <djwong@kernel.org>

Currently, the progress reporting only triggers when the number of bytes
read is exactly a multiple of a megabyte. This isn't always guaranteed,
since AG headers can be 512 bytes in size. Fix the algorithm by
recording the number of megabytes we've reported as being read, and emit
a new report any time the bytes_read count, once converted to megabytes,
doesn't match.

Fix the v2 code to emit one final status message in case the last
extent restored is more than a megabyte.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
mdrestore/xfs_mdrestore.c | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/mdrestore/xfs_mdrestore.c b/mdrestore/xfs_mdrestore.c
index 3f761e8fe8d..ab9a44d2118 100644
--- a/mdrestore/xfs_mdrestore.c
+++ b/mdrestore/xfs_mdrestore.c
@@ -7,6 +7,7 @@
#include "libxfs.h"
#include "xfs_metadump.h"
#include <libfrog/platform.h>
+#include "libfrog/div64.h"

union mdrestore_headers {
__be32 magic;
@@ -160,6 +161,7 @@ restore_v1(
int mb_count;
xfs_sb_t sb;
int64_t bytes_read;
+ int64_t mb_read = 0;

block_size = 1 << h->v1.mb_blocklog;
max_indices = (block_size - sizeof(xfs_metablock_t)) / sizeof(__be64);
@@ -208,9 +210,14 @@ restore_v1(
bytes_read = 0;

for (;;) {
- if (mdrestore.show_progress &&
- (bytes_read & ((1 << 20) - 1)) == 0)
- print_progress("%lld MB read", bytes_read >> 20);
+ if (mdrestore.show_progress) {
+ int64_t mb_now = bytes_read >> 20;
+
+ if (mb_now != mb_read) {
+ print_progress("%lld MB read", mb_now);
+ mb_read = mb_now;
+ }
+ }

for (cur_index = 0; cur_index < mb_count; cur_index++) {
if (pwrite(ddev_fd, &block_buffer[cur_index <<
@@ -240,6 +247,9 @@ restore_v1(
bytes_read += block_size + (mb_count << h->v1.mb_blocklog);
}

+ if (mdrestore.show_progress && bytes_read > (mb_read << 20))
+ print_progress("%lld MB read", howmany_64(bytes_read, 1U << 20));
+
if (mdrestore.progress_since_warning)
putchar('\n');

@@ -340,6 +350,7 @@ restore_v2(
struct xfs_sb sb;
struct xfs_meta_extent xme;
char *block_buffer;
+ int64_t mb_read = 0;
int64_t bytes_read;
uint64_t offset;
int len;
@@ -416,16 +427,18 @@ restore_v2(
bytes_read += len;

if (mdrestore.show_progress) {
- static int64_t mb_read;
- int64_t mb_now = bytes_read >> 20;
+ int64_t mb_now = bytes_read >> 20;

if (mb_now != mb_read) {
- print_progress("%lld MB read", mb_now);
+ print_progress("%lld mb read", mb_now);
mb_read = mb_now;
}
}
} while (1);

+ if (mdrestore.show_progress && bytes_read > (mb_read << 20))
+ print_progress("%lld mb read", howmany_64(bytes_read, 1U << 20));
+
if (mdrestore.progress_since_warning)
putchar('\n');