From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from m16.mail.163.com (m16.mail.163.com [117.135.210.5]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 08DE12063F9; Mon, 7 Apr 2025 01:41:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=117.135.210.5 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743990078; cv=none; b=PUMSHXSDeA0u3YAgkB43V9kT9Ckr+tucK/lVsAuzPpqZHCWOLGJ8INM32CivO9SnZtOu4/GpyGDT3F2t8riWA2LAxQIG8enDY3PEHCDdAD+4BrOPhB6vrIqeYBaiY631of/RYcZOSaFfFeVaDop5x8NmhwGUednvWO773XNlPV8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743990078; c=relaxed/simple; bh=GkbpG4zdHL7ZRFR+4B/BVoLar8zHOqpkqt14tGLhgBQ=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=Vi0OmaYqtvGYdOWVawi2BUBRv2s1y0haagC7GTsxBzayuYKkT+z4aMwBYx8j6tSEvmtDR6RFSxbE+BB9Iy8pPDIe/G7za7AjV/4cgZl9TBrfAkpv4z2VJxNwwiPB8uWiT2d4wcvcVojjGXyp5uSiQ5X5Tn/Y8n3c03jt7DDhg9I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=ddscq2FF; arc=none smtp.client-ip=117.135.210.5 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="ddscq2FF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=Message-ID:Date:MIME-Version:Subject:From: Content-Type; bh=FvmvB2Ur9V3JiBcAElYaFHJ791CrCzjrxmQzbqAxeIs=; b=ddscq2FFzWrFERGU/97MnsJmGwncZGlGBvAU//oe2DaSN4C8aOKIYxp/ZGH++x n9Ao6RQwvxI/TbaRqR0L6c6gmSUUyEynV5+C+tF58CtatFb9dLC5TNi7cT8trY+z BXVwos7tIL0iEKE+0jutLjSm1g9tVPmWEHyYpGr8QaaMs= Received: from [192.168.22.248] (unknown []) by gzga-smtp-mtada-g1-1 (Coremail) with SMTP id _____wDHrzTuLPNnAZvpEg--.33341S2; Mon, 07 Apr 2025 09:40:00 +0800 (CST) Message-ID: <6d1714a4-097e-4d8e-9f2a-907f031ac8f9@163.com> Date: Mon, 7 Apr 2025 09:39:58 +0800 Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4] fs/proc/page: Refactoring to reduce code duplication. From: Liu Ye To: hannes@cmpxchg.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, Andrew Morton Cc: willy@infradead.org, david@redhat.com, svetly.todorov@memverge.com, vbabka@suse.cz, ran.xiaokai@zte.com.cn, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, Liu Ye References: <20250318063226.223284-1-liuyerd@163.com> Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-CM-TRANSID:_____wDHrzTuLPNnAZvpEg--.33341S2 X-Coremail-Antispam: 1Uf129KBjvJXoWxKr45Ww4fWF45Zr47CF1Utrb_yoW3Jry7pF 4kGF4jya18XFyYkr12qws5Za4av3s3AF4jyrW7G3WfXFyqqrnakFySyFnY9FyxCryUZF1x XayqgrnxuFWjyFDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jwa93UUUUU= X-CM-SenderInfo: 5olx5vlug6il2tof0z/xtbBMRoaTGfgx7fuMwACsV 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 >> >> 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 >> >> --- >> 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)