The patch titled
Subject: mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix
has been added to the -mm tree. Its filename is
mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix.patch
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------------------------------------------------------
From: Vlastimil Babka <vbabka@xxxxxxx>
Subject: mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix
>> Hmm IIUC seq_file also provides the buffer and handles feeding the data
>> from there to the user process, which might have called read() with a smaller
>> buffer than that. So I would rather not avoid the seq_file infrastructure.
>> Or you're saying it could be converted to single_open()? Maybe, with more work.
>
> Prefereably yes.
OK here it is. Sending as a new patch instead of delta, as that's easier
to review - the delta is significant. Line stats wise it's the same.
Again a bit less boilerplate thans to no special seq_ops, a bit more
copy/paste in the open and release functions. But I guess it's better
overall.
Link: http://lkml.kernel.org/r/bf4525b0-fd5b-4c4c-2cb3-adee3dd95a48@xxxxxxx
Reported-by: Daniel Colascione <dancol@xxxxxxxxxx>
Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
diff -puN fs/proc/internal.h~mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix fs/proc/internal.h
--- a/fs/proc/internal.h~mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix
+++ a/fs/proc/internal.h
@@ -285,7 +285,6 @@ struct proc_maps_private {
struct inode *inode;
struct task_struct *task;
struct mm_struct *mm;
- struct mem_size_stats *rollup;
#ifdef CONFIG_MMU
struct vm_area_struct *tail_vma;
#endif
diff -puN fs/proc/task_mmu.c~mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix fs/proc/task_mmu.c
--- a/fs/proc/task_mmu.c~mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix
+++ a/fs/proc/task_mmu.c
@@ -247,7 +247,6 @@ static int proc_map_release(struct inode
if (priv->mm)
mmdrop(priv->mm);
- kfree(priv->rollup);
return seq_release_private(inode, file);
}
@@ -417,12 +416,10 @@ struct mem_size_stats {
unsigned long swap;
unsigned long shared_hugetlb;
unsigned long private_hugetlb;
- unsigned long last_vma_end;
u64 pss;
u64 pss_locked;
u64 swap_pss;
bool check_shmem_swap;
- bool finished;
};
static void smaps_account(struct mem_size_stats *mss, struct page *page,
@@ -803,29 +800,48 @@ static int show_smap(struct seq_file *m,
static int show_smaps_rollup(struct seq_file *m, void *v)
{
struct proc_maps_private *priv = m->private;
- struct mem_size_stats *mss = priv->rollup;
+ struct mem_size_stats mss;
+ struct mm_struct *mm;
struct vm_area_struct *vma;
+ unsigned long last_vma_end = 0;
+ int ret = 0;
- /*
- * We might be called multiple times when e.g. the seq buffer
- * overflows. Gather the stats only once.
- */
- if (!mss->finished) {
- for (vma = priv->mm->mmap; vma; vma = vma->vm_next) {
- smap_gather_stats(vma, mss);
- mss->last_vma_end = vma->vm_end;
- }
- mss->finished = true;
+ priv->task = get_proc_task(priv->inode);
+ if (!priv->task)
+ return -ESRCH;
+
+ mm = priv->mm;
+ if (!mm || !mmget_not_zero(mm)) {
+ ret = -ESRCH;
+ goto out_put_task;
+ }
+
+ memset(&mss, 0, sizeof(mss));
+
+ down_read(&mm->mmap_sem);
+ hold_task_mempolicy(priv);
+
+ for (vma = priv->mm->mmap; vma; vma = vma->vm_next) {
+ smap_gather_stats(vma, &mss);
+ last_vma_end = vma->vm_end;
}
show_vma_header_prefix(m, priv->mm->mmap->vm_start,
- mss->last_vma_end, 0, 0, 0, 0);
+ last_vma_end, 0, 0, 0, 0);
seq_pad(m, ' ');
seq_puts(m, "[rollup]\n");
- __show_smap(m, mss);
+ __show_smap(m, &mss);
- return 0;
+ release_task_mempolicy(priv);
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+
+out_put_task:
+ put_task_struct(priv->task);
+ priv->task = NULL;
+
+ return ret;
}
#undef SEQ_PUT_DEC
@@ -836,65 +852,50 @@ static const struct seq_operations proc_
.show = show_smap
};
-static void *smaps_rollup_start(struct seq_file *m, loff_t *ppos)
+static int pid_smaps_open(struct inode *inode, struct file *file)
{
- struct proc_maps_private *priv = m->private;
- struct mm_struct *mm;
-
- if (*ppos != 0)
- return NULL;
+ return do_maps_open(inode, file, &proc_pid_smaps_op);
+}
- priv->task = get_proc_task(priv->inode);
- if (!priv->task)
- return ERR_PTR(-ESRCH);
+static int smaps_rollup_open(struct inode *inode, struct file *file)
+{
+ int ret;
+ struct proc_maps_private *priv;
- mm = priv->mm;
- if (!mm || !mmget_not_zero(mm))
- return NULL;
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
+ if (!priv)
+ return -ENOMEM;
- memset(priv->rollup, 0, sizeof(*priv->rollup));
+ ret = single_open(file, show_smaps_rollup, priv);
+ if (ret)
+ goto out_free;
+
+ priv->inode = inode;
+ priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
+ if (IS_ERR(priv->mm)) {
+ ret = PTR_ERR(priv->mm);
- down_read(&mm->mmap_sem);
- hold_task_mempolicy(priv);
+ single_release(inode, file);
+ goto out_free;
+ }
- return mm;
-}
+ return 0;
-static void *smaps_rollup_next(struct seq_file *m, void *v, loff_t *pos)
-{
- (*pos)++;
- vma_stop(m->private);
- return NULL;
+out_free:
+ kfree(priv);
+ return ret;
}
-static const struct seq_operations proc_pid_smaps_rollup_op = {
- .start = smaps_rollup_start,
- .next = smaps_rollup_next,
- .stop = m_stop,
- .show = show_smaps_rollup
-};
-
-static int pid_smaps_open(struct inode *inode, struct file *file)
+static int smaps_rollup_release(struct inode *inode, struct file *file)
{
- return do_maps_open(inode, file, &proc_pid_smaps_op);
-}
+ struct seq_file *seq = file->private_data;
+ struct proc_maps_private *priv = seq->private;
-static int pid_smaps_rollup_open(struct inode *inode, struct file *file)
-{
- struct seq_file *seq;
- struct proc_maps_private *priv;
- int ret = do_maps_open(inode, file, &proc_pid_smaps_rollup_op);
+ if (priv->mm)
+ mmdrop(priv->mm);
- if (ret < 0)
- return ret;
- seq = file->private_data;
- priv = seq->private;
- priv->rollup = kmalloc(sizeof(*priv->rollup), GFP_KERNEL);
- if (!priv->rollup) {
- proc_map_release(inode, file);
- return -ENOMEM;
- }
- return 0;
+ kfree(priv);
+ return single_release(inode, file);
}
const struct file_operations proc_pid_smaps_operations = {
@@ -905,10 +906,10 @@ const struct file_operations proc_pid_sm
};
const struct file_operations proc_pid_smaps_rollup_operations = {
- .open = pid_smaps_rollup_open,
+ .open = smaps_rollup_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = proc_map_release,
+ .release = smaps_rollup_release,
};
enum clear_refs_types {
_
Patches currently in -mm which might be from vbabka@xxxxxxx are
mm-page_alloc-actually-ignore-mempolicies-for-high-priority-allocations.patch
mm-proc-pid-maps-remove-is_pid-and-related-wrappers.patch
mm-proc-pid-smaps-factor-out-mem-stats-gathering.patch
mm-proc-pid-smaps-factor-out-common-stats-printing.patch
mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file.patch
mm-proc-pid-smaps_rollup-convert-to-single-value-seq_file-fix.patch
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