From: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Subject: 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 Link: http://lkml.kernel.org/r/c0ffb41a-81ac-ddfa-d452-a9229ecc0387@xxxxxxxxxxxxx Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/swapfile.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) --- a/mm/swapfile.c~mm-swapfile-fix-proc-swaps-heading-and-size-used-priority-alignment +++ a/mm/swapfile.c @@ -2801,20 +2801,24 @@ static int swap_show(struct seq_file *sw 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; } _
