mm: swapfile: fix /proc/swaps heading and Size/Used/Priority alignment
Fix the heading and Size/Used/Priority field alignments in /proc/swaps.
If the Size and/or Used value is >= 10000000 (8 bytes), then the
alignment by using tab characters is broken.
This patch maintains the use of tabs for alignment. If spaces are
preferred, we can just use a Field Width specifier for the bytes and
inuse fields. That way those fields don't have to be a multiple of 8
bytes in width. E.g., with a field width of 12, both Size and Used
would always fit on the first line of an 80-column wide terminal (only
Priority would be on the second line).
There are actually 2 problems: heading alignment and field width. On an
xterm, if Used is 7 bytes in length, the tab does nothing, and the
display is like this, with no space/tab between the Used and Priority
fields. (ugh)
Filename Type Size Used Priority
/dev/sda8 partition 16779260 2023012-1
To be clear, if one does 'cat /proc/swaps >/tmp/proc.swaps', it does look
different, like so:
Filename Type Size Used Priority
/dev/sda8 partition 16779260 2086988 -1
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Alexander Viro <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/swapfile.c b/mm/swapfile.c
index c531d26..63ac672 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -2801,20 +2801,24 @@ static int swap_show(struct seq_file *swap, void *v)
struct swap_info_struct *si = v;
struct file *file;
int len;
+ unsigned int bytes, inuse;
if (si == SEQ_START_TOKEN) {
- seq_puts(swap,"Filename\t\t\t\tType\t\tSize\tUsed\tPriority\n");
+ seq_puts(swap,"Filename\t\t\t\tType\t\tSize\t\tUsed\t\tPriority\n");
return 0;
}
+ bytes = si->pages << (PAGE_SHIFT - 10);
+ inuse = si->inuse_pages << (PAGE_SHIFT - 10);
+
file = si->swap_file;
len = seq_file_path(swap, file, " \t\n\\");
- seq_printf(swap, "%*s%s\t%u\t%u\t%d\n",
+ seq_printf(swap, "%*s%s\t%u\t%s%u\t%s%d\n",
len < 40 ? 40 - len : 1, " ",
S_ISBLK(file_inode(file)->i_mode) ?
"partition" : "file\t",
- si->pages << (PAGE_SHIFT - 10),
- si->inuse_pages << (PAGE_SHIFT - 10),
+ bytes, bytes < 10000000 ? "\t" : "",
+ inuse, inuse < 10000000 ? "\t" : "",
si->prio);
return 0;
}
