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

[Chandan Babu R <chandanbabu@kernel.org>]

On Wed, Nov 22, 2023 at 03:07:39 PM -0800, Darrick J. Wong wrote:
> 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.

Looks good to me.

Reviewed-by: Chandan Babu R <chandanbabu@kernel.org>

Thanks especially for fixing all the bugs in metadump & mdrestore.

>
> 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');
>  


-- 
Chandan