Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753755Ab3HADYb (ORCPT ); Wed, 31 Jul 2013 23:24:31 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:6422 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751083Ab3HADYa (ORCPT ); Wed, 31 Jul 2013 23:24:30 -0400 X-IronPort-AV: E=Sophos;i="4.89,791,1367942400"; d="scan'208";a="8083013" Message-ID: <51F9D407.8040703@cn.fujitsu.com> Date: Thu, 01 Aug 2013 11:20:39 +0800 From: Gu Zheng User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:7.0.1) Gecko/20110930 Thunderbird/7.0.1 MIME-Version: 1.0 To: Namjae Jeon CC: jaegeuk.kim@samsung.com, linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Namjae Jeon , Pankaj Kumar Subject: Re: [PATCH 2/2] f2fs: add sysfs entries to select the gc policy References: <1375281193-15560-1-git-send-email-linkinjeon@gmail.com> In-Reply-To: <1375281193-15560-1-git-send-email-linkinjeon@gmail.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/08/01 11:22:13, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/08/01 11:22:14, Serialize complete at 2013/08/01 11:22:14 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7615 Lines: 231 Hi Jeon, On 07/31/2013 10:33 PM, Namjae Jeon wrote: > From: Namjae Jeon > > Add sysfs entries namely gc_long_idle and gc_short_idle to control the > gc policy. Where long idle corresponds to selecting a cost benefit approach, > while short idle corresponds to selecting a greedy approach to garbage > collection. The selection is mutually exclusive one approach will work at > any point. > > Signed-off-by: Namjae Jeon > Signed-off-by: Pankaj Kumar > --- > Documentation/ABI/testing/sysfs-fs-f2fs | 12 +++++++ > Documentation/filesystems/f2fs.txt | 8 +++++ > fs/f2fs/gc.c | 22 ++++++++++-- > fs/f2fs/gc.h | 4 +++ > fs/f2fs/super.c | 59 +++++++++++++++++++++++++++++-- > 5 files changed, 99 insertions(+), 6 deletions(-) > > diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs > index 5f44095..96b62ea 100644 > --- a/Documentation/ABI/testing/sysfs-fs-f2fs > +++ b/Documentation/ABI/testing/sysfs-fs-f2fs > @@ -19,4 +19,16 @@ Description: > Controls the default sleep time for gc_thread. Time > is in milliseconds. > > +What: /sys/fs/f2fs//gc_long_idle > +Date: July 2013 > +Contact: "Namjae Jeon" > +Description: > + Controls the selection of gc policy. long_idle is used > + to select the cost benefit approach for garbage collection. > > +What: /sys/fs/f2fs//gc_short_idle > +Date: July 2013 > +Contact: "Namjae Jeon" > +Description: > + Controls the selection of gc policy. short_idle is used > + to select the greedy approach for garbage collection. > diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt > index 2e9e873..06dd5d7 100644 > --- a/Documentation/filesystems/f2fs.txt > +++ b/Documentation/filesystems/f2fs.txt > @@ -158,6 +158,14 @@ Files in /sys/fs/f2fs/ > time for the garbage collection thread. Time is > in milliseconds. > > + gc_long_idle This parameter controls the selection of cost > + benefit approach for garbage collectoin. Writing > + 1 to this file will select the cost benefit policy. > + > + gc_short_idle This parameter controls the selection of greedy > + approach for the garbage collection. Writing 1 > + to this file will select the greedy policy. Why introduce two opposite attributes? It'll cause some confusion condition if we double enable/disable them. > + > ================================================================================ > USAGE > ================================================================================ > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > index 60d4f67..af2d9d7 100644 > --- a/fs/f2fs/gc.c > +++ b/fs/f2fs/gc.c > @@ -106,6 +106,8 @@ int start_gc_thread(struct f2fs_sb_info *sbi) > gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME; > gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME; > > + gc_th->long_idle = gc_th->short_idle = 0; > + > sbi->gc_thread = gc_th; > init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head); > sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi, > @@ -130,9 +132,23 @@ void stop_gc_thread(struct f2fs_sb_info *sbi) > sbi->gc_thread = NULL; > } > > -static int select_gc_type(int gc_type) > +static int select_gc_type(struct f2fs_gc_kthread *gc_th, int gc_type) > { > - return (gc_type == BG_GC) ? GC_CB : GC_GREEDY; > + int gc_mode; > + > + if (gc_th) { > + if (gc_th->long_idle) { > + gc_mode = GC_CB; > + goto out; > + } else if (gc_th->short_idle) { > + gc_mode = GC_GREEDY; > + goto out; > + } > + } > + > + gc_mode = (gc_type == BG_GC) ? GC_CB : GC_GREEDY; > +out: > + return gc_mode; > } > > static void select_policy(struct f2fs_sb_info *sbi, int gc_type, > @@ -145,7 +161,7 @@ static void select_policy(struct f2fs_sb_info *sbi, int gc_type, > p->dirty_segmap = dirty_i->dirty_segmap[type]; > p->ofs_unit = 1; > } else { > - p->gc_mode = select_gc_type(gc_type); > + p->gc_mode = select_gc_type(sbi->gc_thread, gc_type); > p->dirty_segmap = dirty_i->dirty_segmap[DIRTY]; > p->ofs_unit = sbi->segs_per_sec; > } > diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h > index f4bf44c..b2faae5 100644 > --- a/fs/f2fs/gc.h > +++ b/fs/f2fs/gc.h > @@ -30,6 +30,10 @@ struct f2fs_gc_kthread { > unsigned int min_sleep_time; > unsigned int max_sleep_time; > unsigned int no_gc_sleep_time; > + > + /* for changing gc mode */ > + unsigned int long_idle; > + unsigned int short_idle; The same issue I mentioned in the front patch, they're per f2fs sb infos. Regards, Gu > }; > > struct inode_entry { > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c > index 30de280..3db806b 100644 > --- a/fs/f2fs/super.c > +++ b/fs/f2fs/super.c > @@ -107,6 +107,56 @@ static ssize_t f2fs_sbi_store(struct f2fs_attr *a, > return count; > } > > +static ssize_t f2fs_gc_long_idle_store(struct f2fs_attr *a, > + struct f2fs_sb_info *sbi, > + const char *buf, size_t count) > +{ > + struct f2fs_gc_kthread *gc_kth = sbi->gc_thread; > + unsigned long t; > + ssize_t ret; > + > + if (!gc_kth) > + return -EFAULT; > + > + ret = kstrtoul(skip_spaces(buf), 0, &t); > + if (ret < 0) > + return ret; > + > + if (t == 0) > + gc_kth->long_idle = 0; > + else if (t == 1) { > + gc_kth->long_idle = 1; > + gc_kth->short_idle = 0; > + } > + > + return count; > +} > + > +static ssize_t f2fs_gc_short_idle_store(struct f2fs_attr *a, > + struct f2fs_sb_info *sbi, > + const char *buf, size_t count) > +{ > + struct f2fs_gc_kthread *gc_kth = sbi->gc_thread; > + unsigned long t; > + ssize_t ret; > + > + if (!gc_kth) > + return -EFAULT; > + > + ret = kstrtoul(skip_spaces(buf), 0, &t); > + if (ret < 0) > + return ret; > + > + if (t == 0) > + gc_kth->short_idle = 0; > + else if (t == 1) { > + gc_kth->short_idle = 1; > + gc_kth->long_idle = 0; > + } > + > + return count; > +} > + > static ssize_t f2fs_attr_show(struct kobject *kobj, > struct attribute *attr, char *buf) > { > @@ -142,21 +192,24 @@ static struct f2fs_attr f2fs_attr_##_name = { \ > .offset = offsetof(struct f2fs_gc_kthread, _elname), \ > } > > -#define F2FS_ATTR(name, mode, show, store) \ > -static struct f2fs_attr f2fs_attr_##name = __ATTR(name, mode, show, store) > - > #define F2FS_RW_ATTR(name, elname) \ > F2FS_ATTR_OFFSET(name, 0644, f2fs_sbi_show, f2fs_sbi_store, elname) > > F2FS_RW_ATTR(gc_min_sleep_time, min_sleep_time); > F2FS_RW_ATTR(gc_max_sleep_time, max_sleep_time); > F2FS_RW_ATTR(gc_no_gc_sleep_time, no_gc_sleep_time); > +F2FS_ATTR_OFFSET(gc_long_idle, 0644, f2fs_sbi_show, > + f2fs_gc_long_idle_store, long_idle); > +F2FS_ATTR_OFFSET(gc_short_idle, 0644, f2fs_sbi_show, > + f2fs_gc_short_idle_store, short_idle); > > #define ATTR_LIST(name) (&f2fs_attr_##name.attr) > static struct attribute *f2fs_attrs[] = { > ATTR_LIST(gc_min_sleep_time), > ATTR_LIST(gc_max_sleep_time), > ATTR_LIST(gc_no_gc_sleep_time), > + ATTR_LIST(gc_long_idle), > + ATTR_LIST(gc_short_idle), > NULL, > }; > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/