* [PATCH v4] fs/proc/page: Refactoring to reduce code duplication.
@ 2025-03-18 6:32 Liu Ye
2025-03-18 8:44 ` David Hildenbrand
2025-03-24 3:25 ` Liu Ye
0 siblings, 2 replies; 5+ messages in thread
From: Liu Ye @ 2025-03-18 6:32 UTC (permalink / raw)
To: hannes, mhocko, roman.gushchin, shakeel.butt, muchun.song
Cc: akpm, willy, david, svetly.todorov, vbabka, liuyerd, ran.xiaokai,
linux-kernel, linux-fsdevel, cgroups, linux-mm, Liu Ye
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>
---
V4 : Update code remake patch.
V3 : Add a stub for page_cgroup_ino and remove the #ifdef CONFIG_MEMCG.
V2 : Use an enumeration to indicate the operation to be performed
to avoid passing functions.
---
---
fs/proc/page.c | 161 +++++++++++++------------------------
include/linux/memcontrol.h | 4 +
2 files changed, 58 insertions(+), 107 deletions(-)
diff --git a/fs/proc/page.c b/fs/proc/page.c
index 23fc771100ae..999af26c7298 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -22,6 +22,12 @@
#define KPMMASK (KPMSIZE - 1)
#define KPMBITS (KPMSIZE * BITS_PER_BYTE)
+enum kpage_operation {
+ KPAGE_FLAGS,
+ KPAGE_COUNT,
+ KPAGE_CGROUP,
+};
+
static inline unsigned long get_max_dump_pfn(void)
{
#ifdef CONFIG_SPARSEMEM
@@ -37,19 +43,17 @@ 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,
+ enum kpage_operation op)
{
const unsigned long max_dump_pfn = get_max_dump_pfn();
u64 __user *out = (u64 __user *)buf;
+ struct page *page;
unsigned long src = *ppos;
unsigned long pfn;
ssize_t ret = 0;
+ u64 info;
pfn = src / KPMSIZE;
if (src & KPMMASK || count & KPMMASK)
@@ -59,24 +63,34 @@ 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) {
- struct folio *folio = page_folio(page);
- if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT))
- mapcount = folio_precise_page_mapcount(folio, page);
- else
- mapcount = folio_average_page_mapcount(folio);
- }
-
- if (put_user(mapcount, out)) {
+ if (page) {
+ switch (op) {
+ case KPAGE_FLAGS:
+ info = stable_page_flags(page);
+ break;
+ case KPAGE_COUNT:
+ if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT))
+ info = folio_precise_page_mapcount(page_folio(page), page);
+ else
+ info = folio_average_page_mapcount(page_folio(page));
+ break;
+ case KPAGE_CGROUP:
+ info = page_cgroup_ino(page);
+ break;
+ default:
+ info = 0;
+ break;
+ }
+ } else
+ info = 0;
+
+ if (put_user(info, out)) {
ret = -EFAULT;
break;
}
@@ -94,17 +108,23 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
return ret;
}
+/* /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, KPAGE_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)
{
@@ -225,47 +245,17 @@ u64 stable_page_flags(const struct page *page)
#endif
return u;
-};
+}
+/* /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)
+ size_t count, loff_t *ppos)
{
- 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();
- }
-
- *ppos += (char __user *)out - buf;
- if (!ret)
- ret = (char __user *)out - buf;
- return ret;
+ return kpage_read(file, buf, count, ppos, KPAGE_FLAGS);
}
static const struct proc_ops kpageflags_proc_ops = {
@@ -276,53 +266,10 @@ 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)
+ 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;
+ return kpage_read(file, buf, count, ppos, KPAGE_CGROUP);
}
-
static const struct proc_ops kpagecgroup_proc_ops = {
.proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 53364526d877..5264d148bdd9 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1793,6 +1793,10 @@ static inline void count_objcg_events(struct obj_cgroup *objcg,
{
}
+static inline ino_t page_cgroup_ino(struct page *page)
+{
+ return 0;
+}
#endif /* CONFIG_MEMCG */
#if defined(CONFIG_MEMCG) && defined(CONFIG_ZSWAP)
--
2.25.1
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH v4] fs/proc/page: Refactoring to reduce code duplication.
2025-03-18 6:32 [PATCH v4] fs/proc/page: Refactoring to reduce code duplication Liu Ye
@ 2025-03-18 8:44 ` David Hildenbrand
2025-03-24 3:25 ` Liu Ye
1 sibling, 0 replies; 5+ messages in thread
From: David Hildenbrand @ 2025-03-18 8:44 UTC (permalink / raw)
To: Liu Ye, hannes, mhocko, roman.gushchin, shakeel.butt, muchun.song
Cc: akpm, willy, svetly.todorov, vbabka, ran.xiaokai, linux-kernel,
linux-fsdevel, cgroups, linux-mm, Liu Ye
On 18.03.25 07:32, 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>
>
> ---
> V4 : Update code remake patch.
> V3 : Add a stub for page_cgroup_ino and remove the #ifdef CONFIG_MEMCG.
> V2 : Use an enumeration to indicate the operation to be performed
> to avoid passing functions.
> ---
Acked-by: David Hildenbrand <david@redhat.com>
Thanks!
--
Cheers,
David / dhildenb
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v4] fs/proc/page: Refactoring to reduce code duplication.
2025-03-18 6:32 [PATCH v4] fs/proc/page: Refactoring to reduce code duplication Liu Ye
2025-03-18 8:44 ` David Hildenbrand
@ 2025-03-24 3:25 ` Liu Ye
2025-03-24 11:55 ` David Hildenbrand
2025-04-07 1:39 ` Liu Ye
1 sibling, 2 replies; 5+ messages in thread
From: Liu Ye @ 2025-03-24 3:25 UTC (permalink / raw)
To: hannes, mhocko, roman.gushchin, shakeel.butt, muchun.song
Cc: akpm, willy, david, svetly.todorov, vbabka, ran.xiaokai,
linux-kernel, linux-fsdevel, cgroups, linux-mm, Liu Ye
Friendly ping.
在 2025/3/18 14:32, Liu Ye 写道:
> 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>
>
> ---
> V4 : Update code remake patch.
> V3 : Add a stub for page_cgroup_ino and remove the #ifdef CONFIG_MEMCG.
> V2 : Use an enumeration to indicate the operation to be performed
> to avoid passing functions.
> ---
> ---
> fs/proc/page.c | 161 +++++++++++++------------------------
> include/linux/memcontrol.h | 4 +
> 2 files changed, 58 insertions(+), 107 deletions(-)
>
> diff --git a/fs/proc/page.c b/fs/proc/page.c
> index 23fc771100ae..999af26c7298 100644
> --- a/fs/proc/page.c
> +++ b/fs/proc/page.c
> @@ -22,6 +22,12 @@
> #define KPMMASK (KPMSIZE - 1)
> #define KPMBITS (KPMSIZE * BITS_PER_BYTE)
>
> +enum kpage_operation {
> + KPAGE_FLAGS,
> + KPAGE_COUNT,
> + KPAGE_CGROUP,
> +};
> +
> static inline unsigned long get_max_dump_pfn(void)
> {
> #ifdef CONFIG_SPARSEMEM
> @@ -37,19 +43,17 @@ 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,
> + enum kpage_operation op)
> {
> const unsigned long max_dump_pfn = get_max_dump_pfn();
> u64 __user *out = (u64 __user *)buf;
> + struct page *page;
> unsigned long src = *ppos;
> unsigned long pfn;
> ssize_t ret = 0;
> + u64 info;
>
> pfn = src / KPMSIZE;
> if (src & KPMMASK || count & KPMMASK)
> @@ -59,24 +63,34 @@ 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) {
> - struct folio *folio = page_folio(page);
>
> - if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT))
> - mapcount = folio_precise_page_mapcount(folio, page);
> - else
> - mapcount = folio_average_page_mapcount(folio);
> - }
> -
> - if (put_user(mapcount, out)) {
> + if (page) {
> + switch (op) {
> + case KPAGE_FLAGS:
> + info = stable_page_flags(page);
> + break;
> + case KPAGE_COUNT:
> + if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT))
> + info = folio_precise_page_mapcount(page_folio(page), page);
> + else
> + info = folio_average_page_mapcount(page_folio(page));
> + break;
> + case KPAGE_CGROUP:
> + info = page_cgroup_ino(page);
> + break;
> + default:
> + info = 0;
> + break;
> + }
> + } else
> + info = 0;
> +
> + if (put_user(info, out)) {
> ret = -EFAULT;
> break;
> }
> @@ -94,17 +108,23 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
> return ret;
> }
>
> +/* /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, KPAGE_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)
> {
> @@ -225,47 +245,17 @@ u64 stable_page_flags(const struct page *page)
> #endif
>
> return u;
> -};
> +}
>
> +/* /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)
> + size_t count, loff_t *ppos)
> {
> - 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();
> - }
> -
> - *ppos += (char __user *)out - buf;
> - if (!ret)
> - ret = (char __user *)out - buf;
> - return ret;
> + return kpage_read(file, buf, count, ppos, KPAGE_FLAGS);
> }
>
> static const struct proc_ops kpageflags_proc_ops = {
> @@ -276,53 +266,10 @@ 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)
> + 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;
> + return kpage_read(file, buf, count, ppos, KPAGE_CGROUP);
> }
> -
> static const struct proc_ops kpagecgroup_proc_ops = {
> .proc_flags = PROC_ENTRY_PERMANENT,
> .proc_lseek = mem_lseek,
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index 53364526d877..5264d148bdd9 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -1793,6 +1793,10 @@ static inline void count_objcg_events(struct obj_cgroup *objcg,
> {
> }
>
> +static inline ino_t page_cgroup_ino(struct page *page)
> +{
> + return 0;
> +}
> #endif /* CONFIG_MEMCG */
>
> #if defined(CONFIG_MEMCG) && defined(CONFIG_ZSWAP)
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH v4] fs/proc/page: Refactoring to reduce code duplication.
2025-03-24 3:25 ` Liu Ye
@ 2025-03-24 11:55 ` David Hildenbrand
2025-04-07 1:39 ` Liu Ye
1 sibling, 0 replies; 5+ messages in thread
From: David Hildenbrand @ 2025-03-24 11:55 UTC (permalink / raw)
To: Liu Ye, hannes, mhocko, roman.gushchin, shakeel.butt, muchun.song
Cc: akpm, willy, svetly.todorov, vbabka, ran.xiaokai, linux-kernel,
linux-fsdevel, cgroups, linux-mm, Liu Ye
On 24.03.25 04:25, Liu Ye wrote:
> Friendly ping.
Likely material for after the merge window.
--
Cheers,
David / dhildenb
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v4] fs/proc/page: Refactoring to reduce code duplication.
2025-03-24 3:25 ` Liu Ye
2025-03-24 11:55 ` David Hildenbrand
@ 2025-04-07 1:39 ` Liu Ye
1 sibling, 0 replies; 5+ messages in thread
From: Liu Ye @ 2025-04-07 1:39 UTC (permalink / raw)
To: hannes, mhocko, roman.gushchin, shakeel.butt, muchun.song, Andrew Morton
Cc: willy, david, svetly.todorov, vbabka, ran.xiaokai, linux-kernel,
linux-fsdevel, cgroups, linux-mm, Liu Ye
Friendly ping.
在 2025/3/24 11:25, Liu Ye 写道:
> Friendly ping.
>
> 在 2025/3/18 14:32, Liu Ye 写道:
>> 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>
>>
>> ---
>> V4 : Update code remake patch.
>> V3 : Add a stub for page_cgroup_ino and remove the #ifdef CONFIG_MEMCG.
>> V2 : Use an enumeration to indicate the operation to be performed
>> to avoid passing functions.
>> ---
>> ---
>> fs/proc/page.c | 161 +++++++++++++------------------------
>> include/linux/memcontrol.h | 4 +
>> 2 files changed, 58 insertions(+), 107 deletions(-)
>>
>> diff --git a/fs/proc/page.c b/fs/proc/page.c
>> index 23fc771100ae..999af26c7298 100644
>> --- a/fs/proc/page.c
>> +++ b/fs/proc/page.c
>> @@ -22,6 +22,12 @@
>> #define KPMMASK (KPMSIZE - 1)
>> #define KPMBITS (KPMSIZE * BITS_PER_BYTE)
>>
>> +enum kpage_operation {
>> + KPAGE_FLAGS,
>> + KPAGE_COUNT,
>> + KPAGE_CGROUP,
>> +};
>> +
>> static inline unsigned long get_max_dump_pfn(void)
>> {
>> #ifdef CONFIG_SPARSEMEM
>> @@ -37,19 +43,17 @@ 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,
>> + enum kpage_operation op)
>> {
>> const unsigned long max_dump_pfn = get_max_dump_pfn();
>> u64 __user *out = (u64 __user *)buf;
>> + struct page *page;
>> unsigned long src = *ppos;
>> unsigned long pfn;
>> ssize_t ret = 0;
>> + u64 info;
>>
>> pfn = src / KPMSIZE;
>> if (src & KPMMASK || count & KPMMASK)
>> @@ -59,24 +63,34 @@ 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) {
>> - struct folio *folio = page_folio(page);
>>
>> - if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT))
>> - mapcount = folio_precise_page_mapcount(folio, page);
>> - else
>> - mapcount = folio_average_page_mapcount(folio);
>> - }
>> -
>> - if (put_user(mapcount, out)) {
>> + if (page) {
>> + switch (op) {
>> + case KPAGE_FLAGS:
>> + info = stable_page_flags(page);
>> + break;
>> + case KPAGE_COUNT:
>> + if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT))
>> + info = folio_precise_page_mapcount(page_folio(page), page);
>> + else
>> + info = folio_average_page_mapcount(page_folio(page));
>> + break;
>> + case KPAGE_CGROUP:
>> + info = page_cgroup_ino(page);
>> + break;
>> + default:
>> + info = 0;
>> + break;
>> + }
>> + } else
>> + info = 0;
>> +
>> + if (put_user(info, out)) {
>> ret = -EFAULT;
>> break;
>> }
>> @@ -94,17 +108,23 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
>> return ret;
>> }
>>
>> +/* /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, KPAGE_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)
>> {
>> @@ -225,47 +245,17 @@ u64 stable_page_flags(const struct page *page)
>> #endif
>>
>> return u;
>> -};
>> +}
>>
>> +/* /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)
>> + size_t count, loff_t *ppos)
>> {
>> - 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();
>> - }
>> -
>> - *ppos += (char __user *)out - buf;
>> - if (!ret)
>> - ret = (char __user *)out - buf;
>> - return ret;
>> + return kpage_read(file, buf, count, ppos, KPAGE_FLAGS);
>> }
>>
>> static const struct proc_ops kpageflags_proc_ops = {
>> @@ -276,53 +266,10 @@ 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)
>> + 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;
>> + return kpage_read(file, buf, count, ppos, KPAGE_CGROUP);
>> }
>> -
>> static const struct proc_ops kpagecgroup_proc_ops = {
>> .proc_flags = PROC_ENTRY_PERMANENT,
>> .proc_lseek = mem_lseek,
>> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
>> index 53364526d877..5264d148bdd9 100644
>> --- a/include/linux/memcontrol.h
>> +++ b/include/linux/memcontrol.h
>> @@ -1793,6 +1793,10 @@ static inline void count_objcg_events(struct obj_cgroup *objcg,
>> {
>> }
>>
>> +static inline ino_t page_cgroup_ino(struct page *page)
>> +{
>> + return 0;
>> +}
>> #endif /* CONFIG_MEMCG */
>>
>> #if defined(CONFIG_MEMCG) && defined(CONFIG_ZSWAP)
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2025-04-07 1:40 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2025-03-18 6:32 [PATCH v4] fs/proc/page: Refactoring to reduce code duplication Liu Ye
2025-03-18 8:44 ` David Hildenbrand
2025-03-24 3:25 ` Liu Ye
2025-03-24 11:55 ` David Hildenbrand
2025-04-07 1:39 ` Liu Ye
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox