From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [59.151.112.132] (helo=heian.cn.fujitsu.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZuvKi-00009D-D5 for linux-mtd@lists.infradead.org; Sat, 07 Nov 2015 04:42:34 +0000 Message-ID: <563D7F74.5020109@cn.fujitsu.com> Date: Sat, 7 Nov 2015 12:35:00 +0800 From: Dongsheng Yang MIME-Version: 1.0 To: Richard Weinberger , CC: , Subject: Re: [PATCH v6] ubifs: introduce UBIFS_ATIME_SUPPORT to ubifs References: <1440126626-18446-1-git-send-email-yangds.fnst@cn.fujitsu.com> <56101FC5.6090900@nod.at> <563C71F7.9050004@nod.at> In-Reply-To: <563C71F7.9050004@nod.at> Content-Type: text/plain; charset="ISO-8859-15"; format=flowed Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 11/06/2015 05:25 PM, Richard Weinberger wrote: > Am 03.10.2015 um 20:34 schrieb Richard Weinberger: >> Am 21.08.2015 um 05:10 schrieb Dongsheng Yang: >>> To make ubifs support atime flexily, this commit introduces >>> a Kconfig option named as UBIFS_ATIME_SUPPORT. >>> >>> With UBIFS_ATIME_SUPPORT=n: >>> ubifs keeps the full compatibility to no_atime from >>> the start of ubifs. >>> =================UBIFS_ATIME_SUPPORT=n======================= >>> -o - no atime >>> -o atime - no atime >>> -o noatime - no atime >>> -o relatime - no atime >>> -o strictatime - no atime >>> -o lazyatime - no atime >>> >>> With UBIFS_ATIME_SUPPORT=y: >>> ubifs supports the atime same with other main stream >>> file systems. >>> =================UBIFS_ATIME_SUPPORT=y======================= >>> -o - default behavior (relatime currently) >>> -o atime - atime support >>> -o noatime - no atime support >>> -o relatime - relative atime support >>> -o strictatime - strict atime support >>> -o lazyatime - lazy atime support >>> >>> Signed-off-by: Dongsheng Yang >>> --- >>> -v2: >>> implement update_time for ubifs >>> -v3: >>> Oops, forgot to assign update_time for >>> ubifs_dir_inode_operations. >>> -v4: >>> drop the patch to change 'Y' to 'N' in >>> Kconfig >>> -v5: >>> simplify the warning in atime supporting >>> -v6: >>> * replace ubifs_warn with ubifs_msg >>> * rewrite the messages in Kconfig as Artem suggested >>> * remove S_VERSION related code >>> fs/ubifs/Kconfig | 15 +++++++++++++++ >>> fs/ubifs/dir.c | 3 +++ >>> fs/ubifs/file.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ >>> fs/ubifs/super.c | 12 ++++++++++-- >>> fs/ubifs/ubifs.h | 1 + >>> 5 files changed, 77 insertions(+), 2 deletions(-) >>> >>> diff --git a/fs/ubifs/Kconfig b/fs/ubifs/Kconfig >>> index ba66d50..7ff7712 100644 >>> --- a/fs/ubifs/Kconfig >>> +++ b/fs/ubifs/Kconfig >>> @@ -35,3 +35,18 @@ config UBIFS_FS_ZLIB >>> default y >>> help >>> Zlib compresses better than LZO but it is slower. Say 'Y' if unsure. >>> + >>> +config UBIFS_ATIME_SUPPORT >>> + bool "Access time support" if UBIFS_FS >>> + depends on UBIFS_FS >>> + default n >>> + help >>> + Originally UBIFS did not support atime, because it looked like a bad idea due >>> + increased flash wear. This option adds atime support and it is disabled by default >>> + to preserve the old behavior. If you enable this option, UBIFS starts updating atime, >>> + which means that file-system read operations will cause writes (inode atime >>> + updates). This may affect file-system performance and increase flash device wear, >>> + so be careful. How often atime is updated depends on the selected strategy: >>> + strictatime is the "heavy", relatime is "lighter", etc. >>> + >>> + If unsure, say 'N' >>> diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c >>> index 27060fc..8d93427 100644 >>> --- a/fs/ubifs/dir.c >>> +++ b/fs/ubifs/dir.c >>> @@ -1187,6 +1187,9 @@ const struct inode_operations ubifs_dir_inode_operations = { >>> .getxattr = ubifs_getxattr, >>> .listxattr = ubifs_listxattr, >>> .removexattr = ubifs_removexattr, >>> +#ifdef CONFIG_UBIFS_ATIME_SUPPORT >>> + .update_time = ubifs_update_time, >>> +#endif >>> }; >>> >>> const struct file_operations ubifs_dir_operations = { >>> diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c >>> index 35efc10..423ce6b 100644 >>> --- a/fs/ubifs/file.c >>> +++ b/fs/ubifs/file.c >>> @@ -1364,6 +1364,45 @@ static inline int mctime_update_needed(const struct inode *inode, >>> } >>> >>> /** >>> + * ubifs_update_time - update time of inode. >>> + * @inode: inode to update >>> + * >>> + * This function updates time of the inode. >>> + */ >>> +int ubifs_update_time(struct inode *inode, struct timespec *time, >>> + int flags) >> >> This function should be under an "#ifdef CONFIG_UBIFS_ATIME_SUPPORT". >> >> Beside of that, >> Reviewed-by: Richard Weinberger >> >> I think we can queue it for v4.4. Artem, what do you think? > > Yang, ping? Oh, forgot to update it! Will send a V7 soon. Yang > Artem and I would like to have this in v4.4. > > Thanks, > //richard > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > . >