fs/proc/page.c | 158 ++++++++++++++++--------------------------------- 1 file changed, 50 insertions(+), 108 deletions(-)
From: Liu Ye <liuye@kylinos.cn>
The function kpageflags_read and kpagecgroup_read is quite similar
to kpagecount_read. Consider refactoring common code into a helper
function to reduce code duplication.
Signed-off-by: Liu Ye <liuye@kylinos.cn>
---
fs/proc/page.c | 158 ++++++++++++++++---------------------------------
1 file changed, 50 insertions(+), 108 deletions(-)
diff --git a/fs/proc/page.c b/fs/proc/page.c
index a55f5acefa97..f413016ebe67 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -37,19 +37,17 @@ static inline unsigned long get_max_dump_pfn(void)
#endif
}
-/* /proc/kpagecount - an array exposing page mapcounts
- *
- * Each entry is a u64 representing the corresponding
- * physical page mapcount.
- */
-static ssize_t kpagecount_read(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
+static ssize_t kpage_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos,
+ u64 (*get_page_info)(struct page *))
{
const unsigned long max_dump_pfn = get_max_dump_pfn();
u64 __user *out = (u64 __user *)buf;
+ struct page *ppage;
unsigned long src = *ppos;
unsigned long pfn;
ssize_t ret = 0;
+ u64 info;
pfn = src / KPMSIZE;
if (src & KPMMASK || count & KPMMASK)
@@ -59,19 +57,14 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
count = min_t(unsigned long, count, (max_dump_pfn * KPMSIZE) - src);
while (count > 0) {
- struct page *page;
- u64 mapcount = 0;
-
- /*
- * TODO: ZONE_DEVICE support requires to identify
- * memmaps that were actually initialized.
- */
- page = pfn_to_online_page(pfn);
- if (page)
- mapcount = folio_precise_page_mapcount(page_folio(page),
- page);
-
- if (put_user(mapcount, out)) {
+ ppage = pfn_to_online_page(pfn);
+
+ if (ppage)
+ info = get_page_info(ppage);
+ else
+ info = 0;
+
+ if (put_user(info, out)) {
ret = -EFAULT;
break;
}
@@ -89,17 +82,28 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
return ret;
}
+static u64 get_page_count(struct page *page)
+{
+ return folio_precise_page_mapcount(page_folio(page), page);
+}
+
+/* /proc/kpagecount - an array exposing page mapcounts
+ *
+ * Each entry is a u64 representing the corresponding
+ * physical page mapcount.
+ */
+static ssize_t kpagecount_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return kpage_read(file, buf, count, ppos, get_page_count);
+}
+
static const struct proc_ops kpagecount_proc_ops = {
.proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
.proc_read = kpagecount_read,
};
-/* /proc/kpageflags - an array exposing page flags
- *
- * Each entry is a u64 representing the corresponding
- * physical page flags.
- */
static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit)
{
@@ -220,47 +224,22 @@ u64 stable_page_flags(const struct page *page)
#endif
return u;
-};
+}
-static ssize_t kpageflags_read(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
+static u64 get_page_flags(struct page *page)
{
- const unsigned long max_dump_pfn = get_max_dump_pfn();
- u64 __user *out = (u64 __user *)buf;
- unsigned long src = *ppos;
- unsigned long pfn;
- ssize_t ret = 0;
-
- pfn = src / KPMSIZE;
- if (src & KPMMASK || count & KPMMASK)
- return -EINVAL;
- if (src >= max_dump_pfn * KPMSIZE)
- return 0;
- count = min_t(unsigned long, count, (max_dump_pfn * KPMSIZE) - src);
-
- while (count > 0) {
- /*
- * TODO: ZONE_DEVICE support requires to identify
- * memmaps that were actually initialized.
- */
- struct page *page = pfn_to_online_page(pfn);
-
- if (put_user(stable_page_flags(page), out)) {
- ret = -EFAULT;
- break;
- }
-
- pfn++;
- out++;
- count -= KPMSIZE;
-
- cond_resched();
- }
+ return stable_page_flags(page);
+}
- *ppos += (char __user *)out - buf;
- if (!ret)
- ret = (char __user *)out - buf;
- return ret;
+/* /proc/kpageflags - an array exposing page flags
+ *
+ * Each entry is a u64 representing the corresponding
+ * physical page flags.
+ */
+static ssize_t kpageflags_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return kpage_read(file, buf, count, ppos, get_page_flags);
}
static const struct proc_ops kpageflags_proc_ops = {
@@ -270,54 +249,17 @@ static const struct proc_ops kpageflags_proc_ops = {
};
#ifdef CONFIG_MEMCG
-static ssize_t kpagecgroup_read(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
-{
- const unsigned long max_dump_pfn = get_max_dump_pfn();
- u64 __user *out = (u64 __user *)buf;
- struct page *ppage;
- unsigned long src = *ppos;
- unsigned long pfn;
- ssize_t ret = 0;
- u64 ino;
-
- pfn = src / KPMSIZE;
- if (src & KPMMASK || count & KPMMASK)
- return -EINVAL;
- if (src >= max_dump_pfn * KPMSIZE)
- return 0;
- count = min_t(unsigned long, count, (max_dump_pfn * KPMSIZE) - src);
-
- while (count > 0) {
- /*
- * TODO: ZONE_DEVICE support requires to identify
- * memmaps that were actually initialized.
- */
- ppage = pfn_to_online_page(pfn);
-
- if (ppage)
- ino = page_cgroup_ino(ppage);
- else
- ino = 0;
- if (put_user(ino, out)) {
- ret = -EFAULT;
- break;
- }
-
- pfn++;
- out++;
- count -= KPMSIZE;
-
- cond_resched();
- }
-
- *ppos += (char __user *)out - buf;
- if (!ret)
- ret = (char __user *)out - buf;
- return ret;
+static u64 get_page_cgroup(struct page *page)
+{
+ return page_cgroup_ino(page);
}
+static ssize_t kpagecgroup_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return kpage_read(file, buf, count, ppos, get_page_cgroup);
+}
static const struct proc_ops kpagecgroup_proc_ops = {
.proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
--
2.25.1On 17.03.25 09:01, Liu Ye wrote: > From: Liu Ye <liuye@kylinos.cn> > > The function kpageflags_read and kpagecgroup_read is quite similar > to kpagecount_read. Consider refactoring common code into a helper > function to reduce code duplication. > > Signed-off-by: Liu Ye <liuye@kylinos.cn> > --- > fs/proc/page.c | 158 ++++++++++++++++--------------------------------- > 1 file changed, 50 insertions(+), 108 deletions(-) > > diff --git a/fs/proc/page.c b/fs/proc/page.c > index a55f5acefa97..f413016ebe67 100644 > --- a/fs/proc/page.c > +++ b/fs/proc/page.c > @@ -37,19 +37,17 @@ static inline unsigned long get_max_dump_pfn(void) > #endif > } > > -/* /proc/kpagecount - an array exposing page mapcounts > - * > - * Each entry is a u64 representing the corresponding > - * physical page mapcount. > - */ > -static ssize_t kpagecount_read(struct file *file, char __user *buf, > - size_t count, loff_t *ppos) > +static ssize_t kpage_read(struct file *file, char __user *buf, > + size_t count, loff_t *ppos, > + u64 (*get_page_info)(struct page *)) Can we just indicate using an enum which operation to perform, so we can avoid having+passing these functions? -- Cheers, David / dhildenb
在 2025/3/17 16:56, David Hildenbrand 写道:
> On 17.03.25 09:01, Liu Ye wrote:
>> From: Liu Ye <liuye@kylinos.cn>
>>
>> The function kpageflags_read and kpagecgroup_read is quite similar
>> to kpagecount_read. Consider refactoring common code into a helper
>> function to reduce code duplication.
>>
>> Signed-off-by: Liu Ye <liuye@kylinos.cn>
>> ---
>> fs/proc/page.c | 158 ++++++++++++++++---------------------------------
>> 1 file changed, 50 insertions(+), 108 deletions(-)
>>
>> diff --git a/fs/proc/page.c b/fs/proc/page.c
>> index a55f5acefa97..f413016ebe67 100644
>> --- a/fs/proc/page.c
>> +++ b/fs/proc/page.c
>> @@ -37,19 +37,17 @@ static inline unsigned long get_max_dump_pfn(void)
>> #endif
>> }
>> -/* /proc/kpagecount - an array exposing page mapcounts
>> - *
>> - * Each entry is a u64 representing the corresponding
>> - * physical page mapcount.
>> - */
>> -static ssize_t kpagecount_read(struct file *file, char __user *buf,
>> - size_t count, loff_t *ppos)
>> +static ssize_t kpage_read(struct file *file, char __user *buf,
>> + size_t count, loff_t *ppos,
>> + u64 (*get_page_info)(struct page *))
>
> Can we just indicate using an enum which operation to perform, so we can avoid having+passing these functions?
>
Like this? Good idea, I'll send a new patch later.
enum kpage_operation {
KPAGE_FLAGS,
KPAGE_COUNT,
KPAGE_CGROUP,
};
static u64 get_page_info(struct page *page, enum kpage_operation op)
{
switch (op) {
case KPAGE_FLAGS:
return stable_page_flags(page);
case KPAGE_COUNT:
return page_count(page);
case KPAGE_CGROUP:
return page_cgroup_ino(page);
default:
return 0;
}
}
static ssize_t kpageflags_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
return kpage_read(file, buf, count, ppos, KPAGE_FLAGS);
}
static ssize_t kpagecount_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
return kpage_read(file, buf, count, ppos, KPAGE_COUNT);
}
static ssize_t kpagecgroup_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
return kpage_read(file, buf, count, ppos, KPAGE_CGROUP);
}
static ssize_t kpage_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos,
enum kpage_operation op)
{
...
info = get_page_info(ppage, op);
...
}
On 17.03.25 10:13, Liu Ye wrote:
>
> 在 2025/3/17 16:56, David Hildenbrand 写道:
>> On 17.03.25 09:01, Liu Ye wrote:
>>> From: Liu Ye <liuye@kylinos.cn>
>>>
>>> The function kpageflags_read and kpagecgroup_read is quite similar
>>> to kpagecount_read. Consider refactoring common code into a helper
>>> function to reduce code duplication.
>>>
>>> Signed-off-by: Liu Ye <liuye@kylinos.cn>
>>> ---
>>> fs/proc/page.c | 158 ++++++++++++++++---------------------------------
>>> 1 file changed, 50 insertions(+), 108 deletions(-)
>>>
>>> diff --git a/fs/proc/page.c b/fs/proc/page.c
>>> index a55f5acefa97..f413016ebe67 100644
>>> --- a/fs/proc/page.c
>>> +++ b/fs/proc/page.c
>>> @@ -37,19 +37,17 @@ static inline unsigned long get_max_dump_pfn(void)
>>> #endif
>>> }
>>> -/* /proc/kpagecount - an array exposing page mapcounts
>>> - *
>>> - * Each entry is a u64 representing the corresponding
>>> - * physical page mapcount.
>>> - */
>>> -static ssize_t kpagecount_read(struct file *file, char __user *buf,
>>> - size_t count, loff_t *ppos)
>>> +static ssize_t kpage_read(struct file *file, char __user *buf,
>>> + size_t count, loff_t *ppos,
>>> + u64 (*get_page_info)(struct page *))
>>
>> Can we just indicate using an enum which operation to perform, so we can avoid having+passing these functions?
>>
> Like this? Good idea, I'll send a new patch later.
>
> enum kpage_operation {
> KPAGE_FLAGS,
> KPAGE_COUNT,
> KPAGE_CGROUP,
> };
>
> static u64 get_page_info(struct page *page, enum kpage_operation op)
> {
> switch (op) {
> case KPAGE_FLAGS:
> return stable_page_flags(page);
> case KPAGE_COUNT:
> return page_count(page);
> case KPAGE_CGROUP:
> return page_cgroup_ino(page);
> default:
> return 0;
> }
> }
Likely it's best to inline get_page_info() into kpage_read() to just get
rid of it.
--
Cheers,
David / dhildenb
在 2025/3/17 17:18, David Hildenbrand 写道:
> On 17.03.25 10:13, Liu Ye wrote:
>>
>> 在 2025/3/17 16:56, David Hildenbrand 写道:
>>> On 17.03.25 09:01, Liu Ye wrote:
>>>> From: Liu Ye <liuye@kylinos.cn>
>>>>
>>>> The function kpageflags_read and kpagecgroup_read is quite similar
>>>> to kpagecount_read. Consider refactoring common code into a helper
>>>> function to reduce code duplication.
>>>>
>>>> Signed-off-by: Liu Ye <liuye@kylinos.cn>
>>>> ---
>>>> fs/proc/page.c | 158 ++++++++++++++++---------------------------------
>>>> 1 file changed, 50 insertions(+), 108 deletions(-)
>>>>
>>>> diff --git a/fs/proc/page.c b/fs/proc/page.c
>>>> index a55f5acefa97..f413016ebe67 100644
>>>> --- a/fs/proc/page.c
>>>> +++ b/fs/proc/page.c
>>>> @@ -37,19 +37,17 @@ static inline unsigned long get_max_dump_pfn(void)
>>>> #endif
>>>> }
>>>> -/* /proc/kpagecount - an array exposing page mapcounts
>>>> - *
>>>> - * Each entry is a u64 representing the corresponding
>>>> - * physical page mapcount.
>>>> - */
>>>> -static ssize_t kpagecount_read(struct file *file, char __user *buf,
>>>> - size_t count, loff_t *ppos)
>>>> +static ssize_t kpage_read(struct file *file, char __user *buf,
>>>> + size_t count, loff_t *ppos,
>>>> + u64 (*get_page_info)(struct page *))
>>>
>>> Can we just indicate using an enum which operation to perform, so we can avoid having+passing these functions?
>>>
>> Like this? Good idea, I'll send a new patch later.
>>
>> enum kpage_operation {
>> KPAGE_FLAGS,
>> KPAGE_COUNT,
>> KPAGE_CGROUP,
>> };
>>
>> static u64 get_page_info(struct page *page, enum kpage_operation op)
>> {
>> switch (op) {
>> case KPAGE_FLAGS:
>> return stable_page_flags(page);
>> case KPAGE_COUNT:
>> return page_count(page);
>> case KPAGE_CGROUP:
>> return page_cgroup_ino(page);
>> default:
>> return 0;
>> }
>> }
>
>
> Likely it's best to inline get_page_info() into kpage_read() to just get rid of it.
>
>
Thank you for your suggestion. I agree and will make the changes accordingly.
Thanks,
Liu Ye
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