[PATCH 1/4] mm: /proc/pid/*maps remove is_pid and related wrappers

From: Vlastimil Babka
Date: Mon Jul 23 2018 - 07:20:01 EST


Commit b76437579d13 ("procfs: mark thread stack correctly in proc/<pid>/maps")
introduced differences between /proc/PID/maps and /proc/PID/task/TID/maps to
mark thread stacks properly, and this was also done for smaps and numa_maps.
However it didn't work properly and was ultimately removed by commit
b18cb64ead40 ("fs/proc: Stop trying to report thread stacks").

Now the is_pid parameter for the related show_*() functions is unused and we
can remove it together with wrapper functions and ops structures that differ
for PID and TID cases only in this parameter.

Signed-off-by: Vlastimil Babka <vbabka@xxxxxxx>
---
fs/proc/base.c | 6 +--
fs/proc/internal.h | 3 --
fs/proc/task_mmu.c | 114 +++++--------------------------------------
fs/proc/task_nommu.c | 39 ++-------------
4 files changed, 18 insertions(+), 144 deletions(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index aaffc0c30216..ad047977ed04 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3309,12 +3309,12 @@ static const struct pid_entry tid_base_stuff[] = {
REG("cmdline", S_IRUGO, proc_pid_cmdline_ops),
ONE("stat", S_IRUGO, proc_tid_stat),
ONE("statm", S_IRUGO, proc_pid_statm),
- REG("maps", S_IRUGO, proc_tid_maps_operations),
+ REG("maps", S_IRUGO, proc_pid_maps_operations),
#ifdef CONFIG_PROC_CHILDREN
REG("children", S_IRUGO, proc_tid_children_operations),
#endif
#ifdef CONFIG_NUMA
- REG("numa_maps", S_IRUGO, proc_tid_numa_maps_operations),
+ REG("numa_maps", S_IRUGO, proc_pid_numa_maps_operations),
#endif
REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations),
LNK("cwd", proc_cwd_link),
@@ -3324,7 +3324,7 @@ static const struct pid_entry tid_base_stuff[] = {
REG("mountinfo", S_IRUGO, proc_mountinfo_operations),
#ifdef CONFIG_PROC_PAGE_MONITOR
REG("clear_refs", S_IWUSR, proc_clear_refs_operations),
- REG("smaps", S_IRUGO, proc_tid_smaps_operations),
+ REG("smaps", S_IRUGO, proc_pid_smaps_operations),
REG("smaps_rollup", S_IRUGO, proc_pid_smaps_rollup_operations),
REG("pagemap", S_IRUSR, proc_pagemap_operations),
#endif
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index da3dbfa09e79..0c538769512a 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -297,12 +297,9 @@ struct proc_maps_private {
struct mm_struct *proc_mem_open(struct inode *inode, unsigned int mode);

extern const struct file_operations proc_pid_maps_operations;
-extern const struct file_operations proc_tid_maps_operations;
extern const struct file_operations proc_pid_numa_maps_operations;
-extern const struct file_operations proc_tid_numa_maps_operations;
extern const struct file_operations proc_pid_smaps_operations;
extern const struct file_operations proc_pid_smaps_rollup_operations;
-extern const struct file_operations proc_tid_smaps_operations;
extern const struct file_operations proc_clear_refs_operations;
extern const struct file_operations proc_pagemap_operations;

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index dfd73a4616ce..a3f98ca50981 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -294,7 +294,7 @@ static void show_vma_header_prefix(struct seq_file *m,
}

static void
-show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
+show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
{
struct mm_struct *mm = vma->vm_mm;
struct file *file = vma->vm_file;
@@ -357,35 +357,18 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
seq_putc(m, '\n');
}

-static int show_map(struct seq_file *m, void *v, int is_pid)
+static int show_map(struct seq_file *m, void *v)
{
- show_map_vma(m, v, is_pid);
+ show_map_vma(m, v);
m_cache_vma(m, v);
return 0;
}

-static int show_pid_map(struct seq_file *m, void *v)
-{
- return show_map(m, v, 1);
-}
-
-static int show_tid_map(struct seq_file *m, void *v)
-{
- return show_map(m, v, 0);
-}
-
static const struct seq_operations proc_pid_maps_op = {
.start = m_start,
.next = m_next,
.stop = m_stop,
- .show = show_pid_map
-};
-
-static const struct seq_operations proc_tid_maps_op = {
- .start = m_start,
- .next = m_next,
- .stop = m_stop,
- .show = show_tid_map
+ .show = show_map
};

static int pid_maps_open(struct inode *inode, struct file *file)
@@ -393,11 +376,6 @@ static int pid_maps_open(struct inode *inode, struct file *file)
return do_maps_open(inode, file, &proc_pid_maps_op);
}

-static int tid_maps_open(struct inode *inode, struct file *file)
-{
- return do_maps_open(inode, file, &proc_tid_maps_op);
-}
-
const struct file_operations proc_pid_maps_operations = {
.open = pid_maps_open,
.read = seq_read,
@@ -405,13 +383,6 @@ const struct file_operations proc_pid_maps_operations = {
.release = proc_map_release,
};

-const struct file_operations proc_tid_maps_operations = {
- .open = tid_maps_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = proc_map_release,
-};
-
/*
* Proportional Set Size(PSS): my share of RSS.
*
@@ -733,7 +704,7 @@ static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,

#define SEQ_PUT_DEC(str, val) \
seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
-static int show_smap(struct seq_file *m, void *v, int is_pid)
+static int show_smap(struct seq_file *m, void *v)
{
struct proc_maps_private *priv = m->private;
struct vm_area_struct *vma = v;
@@ -796,7 +767,7 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
mss->pss_locked += mss->pss;

if (!rollup_mode) {
- show_map_vma(m, vma, is_pid);
+ show_map_vma(m, vma);
} else if (last_vma) {
show_vma_header_prefix(
m, mss->first_vma_start, vma->vm_end, 0, 0, 0, 0);
@@ -845,28 +816,11 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
}
#undef SEQ_PUT_DEC

-static int show_pid_smap(struct seq_file *m, void *v)
-{
- return show_smap(m, v, 1);
-}
-
-static int show_tid_smap(struct seq_file *m, void *v)
-{
- return show_smap(m, v, 0);
-}
-
static const struct seq_operations proc_pid_smaps_op = {
.start = m_start,
.next = m_next,
.stop = m_stop,
- .show = show_pid_smap
-};
-
-static const struct seq_operations proc_tid_smaps_op = {
- .start = m_start,
- .next = m_next,
- .stop = m_stop,
- .show = show_tid_smap
+ .show = show_smap
};

static int pid_smaps_open(struct inode *inode, struct file *file)
@@ -893,11 +847,6 @@ static int pid_smaps_rollup_open(struct inode *inode, struct file *file)
return 0;
}

-static int tid_smaps_open(struct inode *inode, struct file *file)
-{
- return do_maps_open(inode, file, &proc_tid_smaps_op);
-}
-
const struct file_operations proc_pid_smaps_operations = {
.open = pid_smaps_open,
.read = seq_read,
@@ -912,13 +861,6 @@ const struct file_operations proc_pid_smaps_rollup_operations = {
.release = proc_map_release,
};

-const struct file_operations proc_tid_smaps_operations = {
- .open = tid_smaps_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = proc_map_release,
-};
-
enum clear_refs_types {
CLEAR_REFS_ALL = 1,
CLEAR_REFS_ANON,
@@ -1728,7 +1670,7 @@ static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
/*
* Display pages allocated per node and memory policy via /proc.
*/
-static int show_numa_map(struct seq_file *m, void *v, int is_pid)
+static int show_numa_map(struct seq_file *m, void *v)
{
struct numa_maps_private *numa_priv = m->private;
struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
@@ -1812,45 +1754,17 @@ static int show_numa_map(struct seq_file *m, void *v, int is_pid)
return 0;
}

-static int show_pid_numa_map(struct seq_file *m, void *v)
-{
- return show_numa_map(m, v, 1);
-}
-
-static int show_tid_numa_map(struct seq_file *m, void *v)
-{
- return show_numa_map(m, v, 0);
-}
-
static const struct seq_operations proc_pid_numa_maps_op = {
.start = m_start,
.next = m_next,
.stop = m_stop,
- .show = show_pid_numa_map,
+ .show = show_numa_map,
};

-static const struct seq_operations proc_tid_numa_maps_op = {
- .start = m_start,
- .next = m_next,
- .stop = m_stop,
- .show = show_tid_numa_map,
-};
-
-static int numa_maps_open(struct inode *inode, struct file *file,
- const struct seq_operations *ops)
-{
- return proc_maps_open(inode, file, ops,
- sizeof(struct numa_maps_private));
-}
-
static int pid_numa_maps_open(struct inode *inode, struct file *file)
{
- return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
-}
-
-static int tid_numa_maps_open(struct inode *inode, struct file *file)
-{
- return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
+ return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
+ sizeof(struct numa_maps_private));
}

const struct file_operations proc_pid_numa_maps_operations = {
@@ -1860,10 +1774,4 @@ const struct file_operations proc_pid_numa_maps_operations = {
.release = proc_map_release,
};

-const struct file_operations proc_tid_numa_maps_operations = {
- .open = tid_numa_maps_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = proc_map_release,
-};
#endif /* CONFIG_NUMA */
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 5b62f57bd9bc..0b63d68dedb2 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -142,8 +142,7 @@ static int is_stack(struct vm_area_struct *vma)
/*
* display a single VMA to a sequenced file
*/
-static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma,
- int is_pid)
+static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma)
{
struct mm_struct *mm = vma->vm_mm;
unsigned long ino = 0;
@@ -189,22 +188,11 @@ static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma,
/*
* display mapping lines for a particular process's /proc/pid/maps
*/
-static int show_map(struct seq_file *m, void *_p, int is_pid)
+static int show_map(struct seq_file *m, void *_p)
{
struct rb_node *p = _p;

- return nommu_vma_show(m, rb_entry(p, struct vm_area_struct, vm_rb),
- is_pid);
-}
-
-static int show_pid_map(struct seq_file *m, void *_p)
-{
- return show_map(m, _p, 1);
-}
-
-static int show_tid_map(struct seq_file *m, void *_p)
-{
- return show_map(m, _p, 0);
+ return nommu_vma_show(m, rb_entry(p, struct vm_area_struct, vm_rb));
}

static void *m_start(struct seq_file *m, loff_t *pos)
@@ -260,14 +248,7 @@ static const struct seq_operations proc_pid_maps_ops = {
.start = m_start,
.next = m_next,
.stop = m_stop,
- .show = show_pid_map
-};
-
-static const struct seq_operations proc_tid_maps_ops = {
- .start = m_start,
- .next = m_next,
- .stop = m_stop,
- .show = show_tid_map
+ .show = show_map
};

static int maps_open(struct inode *inode, struct file *file,
@@ -308,11 +289,6 @@ static int pid_maps_open(struct inode *inode, struct file *file)
return maps_open(inode, file, &proc_pid_maps_ops);
}

-static int tid_maps_open(struct inode *inode, struct file *file)
-{
- return maps_open(inode, file, &proc_tid_maps_ops);
-}
-
const struct file_operations proc_pid_maps_operations = {
.open = pid_maps_open,
.read = seq_read,
@@ -320,10 +296,3 @@ const struct file_operations proc_pid_maps_operations = {
.release = map_release,
};

-const struct file_operations proc_tid_maps_operations = {
- .open = tid_maps_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = map_release,
-};
-
--
2.18.0