| Message ID | 20250317080118.95696-1-liuyerd@163.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | fs/proc/page: Refactoring to reduce code duplication. | expand |
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?
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.
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
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,