diff options
| author | Joe Korty <joe.korty@ccur.com> | 2008-10-16 15:27:09 +0400 |
|---|---|---|
| committer | Alexey Dobriyan <adobriyan@gmail.com> | 2008-10-23 13:21:29 +0400 |
| commit | 7c88db0cb589df980acfb2f73c3595a0653004ec (patch) | |
| tree | f3e6400704e9a9fdbaea3c8ee83026763f92627d /fs | |
| parent | 2515ddc6db8eb49a79f0fe5e67ff09ac7c81eab4 (diff) | |
proc: fix vma display mismatch between /proc/pid/{maps,smaps}
Commit 4752c369789250eafcd7813e11c8fb689235b0d2 aka
"maps4: simplify interdependence of maps and smaps" broke /proc/pid/smaps,
causing it to display some vmas twice and other vmas not at all. For example:
grep .- /proc/1/smaps >/tmp/smaps; diff /proc/1/maps /tmp/smaps
1 25d24
2 < 7fd7e23aa000-7fd7e23ac000 rw-p 7fd7e23aa000 00:00 0
3 28a28
4 > ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
The bug has something to do with setting m->version before all the
seq_printf's have been performed. show_map was doing this correctly,
but show_smap was doing this in the middle of its seq_printf sequence.
This patch arranges things so that the setting of m->version in show_smap
is also done at the end of its seq_printf sequence.
Testing: in addition to the above grep test, for each process I summed
up the 'Rss' fields of /proc/pid/smaps and compared that to the 'VmRSS'
field of /proc/pid/status. All matched except for Xorg (which has a
/dev/mem mapping which Rss accounts for but VmRSS does not). This result
gives us some confidence that neither /proc/pid/maps nor /proc/pid/smaps
are any longer skipping or double-counting vmas.
Signed-off-by: Joe Korty <joe.korty@ccur.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/proc/task_mmu.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 4806830ea2a..b770c095e45 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -198,11 +198,8 @@ static int do_maps_open(struct inode *inode, struct file *file, return ret; } -static int show_map(struct seq_file *m, void *v) +static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma) { - struct proc_maps_private *priv = m->private; - struct task_struct *task = priv->task; - struct vm_area_struct *vma = v; struct mm_struct *mm = vma->vm_mm; struct file *file = vma->vm_file; int flags = vma->vm_flags; @@ -254,6 +251,15 @@ static int show_map(struct seq_file *m, void *v) } } seq_putc(m, '\n'); +} + +static int show_map(struct seq_file *m, void *v) +{ + struct vm_area_struct *vma = v; + struct proc_maps_private *priv = m->private; + struct task_struct *task = priv->task; + + show_map_vma(m, vma); if (m->count < m->size) /* vma is copied successfully */ m->version = (vma != get_gate_vma(task))? vma->vm_start: 0; @@ -364,9 +370,10 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, static int show_smap(struct seq_file *m, void *v) { + struct proc_maps_private *priv = m->private; + struct task_struct *task = priv->task; struct vm_area_struct *vma = v; struct mem_size_stats mss; - int ret; struct mm_walk smaps_walk = { .pmd_entry = smaps_pte_range, .mm = vma->vm_mm, @@ -378,9 +385,7 @@ static int show_smap(struct seq_file *m, void *v) if (vma->vm_mm && !is_vm_hugetlb_page(vma)) walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk); - ret = show_map(m, v); - if (ret) - return ret; + show_map_vma(m, vma); seq_printf(m, "Size: %8lu kB\n" @@ -402,7 +407,9 @@ static int show_smap(struct seq_file *m, void *v) mss.referenced >> 10, mss.swap >> 10); - return ret; + if (m->count < m->size) /* vma is copied successfully */ + m->version = (vma != get_gate_vma(task)) ? vma->vm_start : 0; + return 0; } static const struct seq_operations proc_pid_smaps_op = { |