Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1692889 > unrolled thread

Re: [PATCH] f2fs: let __get_victim successfully get a segno in corner case

Started byYunlong Song <yunlong.song@huawei.com>
First post2017-07-20 14:40 +0200
Last post2017-07-24 11:30 +0200
Articles 3 — 2 participants

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  Re: [PATCH] f2fs: let __get_victim successfully get a segno in corner  case Yunlong Song <yunlong.song@huawei.com> - 2017-07-20 14:40 +0200
    Re: [PATCH] f2fs: let __get_victim successfully get a segno in  corner case Jaegeuk Kim <jaegeuk@kernel.org> - 2017-07-21 23:10 +0200
      Re: [PATCH] f2fs: let __get_victim successfully get a segno in corner  case Yunlong Song <yunlong.song@huawei.com> - 2017-07-24 11:30 +0200

#1692889 — Re: [PATCH] f2fs: let __get_victim successfully get a segno in corner case

FromYunlong Song <yunlong.song@huawei.com>
Date2017-07-20 14:40 +0200
SubjectRe: [PATCH] f2fs: let __get_victim successfully get a segno in corner case
Message-ID<u5iUj-7pn-39@gated-at.bofh.it>
Hi, Jay,
    The distribution is like this, unit is segment counts:
    cnt_free: 0 (free blocks)
    cnt_full: 25182 (segment which has 512 blocks)
    cnt_over: 25192 (segment which valid blocks over fggc_threshold)
    cnt_below: 870 (segment which valid blocks below fggc_threshold)

The test is fragment test, add and delete small files over and over.

On 2017/7/18 0:56, Jaegeuk Kim wrote:
> On 07/16, sylinux wrote:
>> In fact，this is not "suppose" case yet, we have already met this problem several times in some test suits for corner case, or I cannot notice that this could happen.
> So, have you taken a look at distribution of valid blocks in that case?
> I'm wondering what distribution can cause this.
>
> Thanks,
>
>>
>>
>>
>> 发自网易邮箱大师
>> On 07/16/2017 09:09, Jaegeuk Kim wrote:
>> Hi Yunlong,
>>
>> On 07/14, Yunlong Song wrote:
>>> Suppose that the valid blocks of each section are all over sbi->fggc_threshold,
>> How about adding a kernel message first to detect your *supposed* sceanrio?
>> If that happens, it'll be a sort of bug which we haven't assumed.
>>
>> Thanks,
>>
>>> and even has_not_enough_free_secs is true, f2fs_gc cannot do its job since the
>>> no_fggc_candidate always returns true. As a result, the reserved segments can be
>>> used up, and finally there is no free segment at all, and get_new_segment cannot
>>> get a free segment, filesystem will trap into a wrong status.
>>>
>>> To fix this, we record the segno which has a rough minimum cost and return it to
>>> __get_victim to continue f2fs_gc's job.
>>>
>>> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
>>> ---
>>>  fs/f2fs/gc.c      | 19 ++++++++++++++-----
>>>  fs/f2fs/segment.h | 17 ++++++++++++++---
>>>  2 files changed, 28 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>>> index fa3d2e2..965e783 100644
>>> --- a/fs/f2fs/gc.c
>>> +++ b/fs/f2fs/gc.c
>>> @@ -178,6 +178,8 @@ static void select_policy(struct f2fs_sb_info *sbi, int gc_type,
>>>          p->offset = 0;
>>>      else
>>>          p->offset = SIT_I(sbi)->last_victim[p->gc_mode];
>>> +
>>> +    p->min_cost_r = UINT_MAX;
>>>  }
>>>  
>>>  static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
>>> @@ -194,7 +196,7 @@ static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
>>>          return 0;
>>>  }
>>>  
>>> -static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
>>> +static unsigned int check_bg_victims(struct f2fs_sb_info *sbi, struct victim_sel_policy *p)
>>>  {
>>>      struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
>>>      unsigned int secno;
>>> @@ -208,11 +210,12 @@ static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
>>>          if (sec_usage_check(sbi, secno))
>>>              continue;
>>>  
>>> -        if (no_fggc_candidate(sbi, secno))
>>> +        p->cur_segno_r = GET_SEG_FROM_SEC(sbi, secno);
>>> +        if (no_fggc_candidate(sbi, secno, p))
>>>              continue;
>>>  
>>>          clear_bit(secno, dirty_i->victim_secmap);
>>> -        return GET_SEG_FROM_SEC(sbi, secno);
>>> +        return p->cur_segno_r;
>>>      }
>>>      return NULL_SEGNO;
>>>  }
>>> @@ -332,7 +335,7 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
>>>  
>>>      last_victim = sm->last_victim[p.gc_mode];
>>>      if (p.alloc_mode == LFS && gc_type == FG_GC) {
>>> -        p.min_segno = check_bg_victims(sbi);
>>> +        p.min_segno = check_bg_victims(sbi, &p);
>>>          if (p.min_segno != NULL_SEGNO)
>>>              goto got_it;
>>>      }
>>> @@ -369,8 +372,9 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
>>>              goto next;
>>>          if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap))
>>>              goto next;
>>> +        p.cur_segno_r = segno;
>>>          if (gc_type == FG_GC && p.alloc_mode == LFS &&
>>> -                    no_fggc_candidate(sbi, secno))
>>> +                    no_fggc_candidate(sbi, secno, &p))
>>>              goto next;
>>>  
>>>          cost = get_gc_cost(sbi, segno, &p);
>>> @@ -403,6 +407,11 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
>>>          trace_f2fs_get_victim(sbi->sb, type, gc_type, &p,
>>>                  sbi->cur_victim_sec,
>>>                  prefree_segments(sbi), free_segments(sbi));
>>> +    } else if (has_not_enough_free_secs(sbi, 0, 0)) {
>>> +        p.min_segno = p.min_segno_r;
>>> +        if (p.alloc_mode == LFS && gc_type == FG_GC)
>>> +            clear_bit(GET_SEC_FROM_SEG(sbi, p.min_segno), dirty_i->victim_secmap);
>>> +        goto got_it;
>>>      }
>>>  out:
>>>      mutex_unlock(&dirty_i->seglist_lock);
>>> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
>>> index 6b871b4..7d2d0f3 100644
>>> --- a/fs/f2fs/segment.h
>>> +++ b/fs/f2fs/segment.h
>>> @@ -169,6 +169,9 @@ struct victim_sel_policy {
>>>      unsigned int ofs_unit;        /* bitmap search unit */
>>>      unsigned int min_cost;        /* minimum cost */
>>>      unsigned int min_segno;        /* segment # having min. cost */
>>> +    unsigned int min_cost_r;        /* rough minimum cost */
>>> +    unsigned int min_segno_r;        /* segment # having rough min. cost */
>>> +    unsigned int cur_segno_r;        /* segment # rough process is handling */
>>>  };
>>>  
>>>  struct seg_entry {
>>> @@ -743,11 +746,19 @@ static inline block_t sum_blk_addr(struct f2fs_sb_info *sbi, int base, int type)
>>>  }
>>>  
>>>  static inline bool no_fggc_candidate(struct f2fs_sb_info *sbi,
>>> -                        unsigned int secno)
>>> +                        unsigned int secno, struct victim_sel_policy *p)
>>>  {
>>> -    if (get_valid_blocks(sbi, GET_SEG_FROM_SEC(sbi, secno), true) >=
>>> -                        sbi->fggc_threshold)
>>> +    unsigned int cur_cost;
>>> +
>>> +    cur_cost = get_valid_blocks(sbi, GET_SEG_FROM_SEC(sbi, secno), true);
>>> +    if (cur_cost >= sbi->fggc_threshold) {
>>> +        if (p->min_cost_r > cur_cost) {
>>> +            p->min_cost_r = cur_cost;
>>> +            p->min_segno_r = p->cur_segno_r;
>>> +        }
>>>          return true;
>>> +    }
>>> +
>>>      return false;
>>>  }
>>>  
>>> --
>>> 1.8.5.2
> .
>


-- 
Thanks,
Yunlong Song

[toc] | [next] | [standalone]

#1693986 — Re: [PATCH] f2fs: let __get_victim successfully get a segno in corner case

FromJaegeuk Kim <jaegeuk@kernel.org>
Date2017-07-21 23:10 +0200
SubjectRe: [PATCH] f2fs: let __get_victim successfully get a segno in corner case
Message-ID<u5Nlo-1qy-1@gated-at.bofh.it>
In reply to#1692889
Hi Yunlong,

On 07/20, Yunlong Song wrote:
> Hi, Jay,
>     The distribution is like this, unit is segment counts:
>     cnt_free: 0 (free blocks)
>     cnt_full: 25182 (segment which has 512 blocks)
>     cnt_over: 25192 (segment which valid blocks over fggc_threshold)
>     cnt_below: 870 (segment which valid blocks below fggc_threshold)

What are the values of fggc_threshold and ovp ratio or reserved_segments?
How was the proc/segment_info?

Thanks,

> 
> The test is fragment test, add and delete small files over and over.
> 
> On 2017/7/18 0:56, Jaegeuk Kim wrote:
> > On 07/16, sylinux wrote:
> >> In fact，this is not "suppose" case yet, we have already met this problem several times in some test suits for corner case, or I cannot notice that this could happen.
> > So, have you taken a look at distribution of valid blocks in that case?
> > I'm wondering what distribution can cause this.
> >
> > Thanks,
> >
> >>
> >>
> >>
> >> 发自网易邮箱大师
> >> On 07/16/2017 09:09, Jaegeuk Kim wrote:
> >> Hi Yunlong,
> >>
> >> On 07/14, Yunlong Song wrote:
> >>> Suppose that the valid blocks of each section are all over sbi->fggc_threshold,
> >> How about adding a kernel message first to detect your *supposed* sceanrio?
> >> If that happens, it'll be a sort of bug which we haven't assumed.
> >>
> >> Thanks,
> >>
> >>> and even has_not_enough_free_secs is true, f2fs_gc cannot do its job since the
> >>> no_fggc_candidate always returns true. As a result, the reserved segments can be
> >>> used up, and finally there is no free segment at all, and get_new_segment cannot
> >>> get a free segment, filesystem will trap into a wrong status.
> >>>
> >>> To fix this, we record the segno which has a rough minimum cost and return it to
> >>> __get_victim to continue f2fs_gc's job.
> >>>
> >>> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
> >>> ---
> >>>  fs/f2fs/gc.c      | 19 ++++++++++++++-----
> >>>  fs/f2fs/segment.h | 17 ++++++++++++++---
> >>>  2 files changed, 28 insertions(+), 8 deletions(-)
> >>>
> >>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> >>> index fa3d2e2..965e783 100644
> >>> --- a/fs/f2fs/gc.c
> >>> +++ b/fs/f2fs/gc.c
> >>> @@ -178,6 +178,8 @@ static void select_policy(struct f2fs_sb_info *sbi, int gc_type,
> >>>          p->offset = 0;
> >>>      else
> >>>          p->offset = SIT_I(sbi)->last_victim[p->gc_mode];
> >>> +
> >>> +    p->min_cost_r = UINT_MAX;
> >>>  }
> >>>  
> >>>  static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
> >>> @@ -194,7 +196,7 @@ static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
> >>>          return 0;
> >>>  }
> >>>  
> >>> -static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
> >>> +static unsigned int check_bg_victims(struct f2fs_sb_info *sbi, struct victim_sel_policy *p)
> >>>  {
> >>>      struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
> >>>      unsigned int secno;
> >>> @@ -208,11 +210,12 @@ static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
> >>>          if (sec_usage_check(sbi, secno))
> >>>              continue;
> >>>  
> >>> -        if (no_fggc_candidate(sbi, secno))
> >>> +        p->cur_segno_r = GET_SEG_FROM_SEC(sbi, secno);
> >>> +        if (no_fggc_candidate(sbi, secno, p))
> >>>              continue;
> >>>  
> >>>          clear_bit(secno, dirty_i->victim_secmap);
> >>> -        return GET_SEG_FROM_SEC(sbi, secno);
> >>> +        return p->cur_segno_r;
> >>>      }
> >>>      return NULL_SEGNO;
> >>>  }
> >>> @@ -332,7 +335,7 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
> >>>  
> >>>      last_victim = sm->last_victim[p.gc_mode];
> >>>      if (p.alloc_mode == LFS && gc_type == FG_GC) {
> >>> -        p.min_segno = check_bg_victims(sbi);
> >>> +        p.min_segno = check_bg_victims(sbi, &p);
> >>>          if (p.min_segno != NULL_SEGNO)
> >>>              goto got_it;
> >>>      }
> >>> @@ -369,8 +372,9 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
> >>>              goto next;
> >>>          if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap))
> >>>              goto next;
> >>> +        p.cur_segno_r = segno;
> >>>          if (gc_type == FG_GC && p.alloc_mode == LFS &&
> >>> -                    no_fggc_candidate(sbi, secno))
> >>> +                    no_fggc_candidate(sbi, secno, &p))
> >>>              goto next;
> >>>  
> >>>          cost = get_gc_cost(sbi, segno, &p);
> >>> @@ -403,6 +407,11 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
> >>>          trace_f2fs_get_victim(sbi->sb, type, gc_type, &p,
> >>>                  sbi->cur_victim_sec,
> >>>                  prefree_segments(sbi), free_segments(sbi));
> >>> +    } else if (has_not_enough_free_secs(sbi, 0, 0)) {
> >>> +        p.min_segno = p.min_segno_r;
> >>> +        if (p.alloc_mode == LFS && gc_type == FG_GC)
> >>> +            clear_bit(GET_SEC_FROM_SEG(sbi, p.min_segno), dirty_i->victim_secmap);
> >>> +        goto got_it;
> >>>      }
> >>>  out:
> >>>      mutex_unlock(&dirty_i->seglist_lock);
> >>> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
> >>> index 6b871b4..7d2d0f3 100644
> >>> --- a/fs/f2fs/segment.h
> >>> +++ b/fs/f2fs/segment.h
> >>> @@ -169,6 +169,9 @@ struct victim_sel_policy {
> >>>      unsigned int ofs_unit;        /* bitmap search unit */
> >>>      unsigned int min_cost;        /* minimum cost */
> >>>      unsigned int min_segno;        /* segment # having min. cost */
> >>> +    unsigned int min_cost_r;        /* rough minimum cost */
> >>> +    unsigned int min_segno_r;        /* segment # having rough min. cost */
> >>> +    unsigned int cur_segno_r;        /* segment # rough process is handling */
> >>>  };
> >>>  
> >>>  struct seg_entry {
> >>> @@ -743,11 +746,19 @@ static inline block_t sum_blk_addr(struct f2fs_sb_info *sbi, int base, int type)
> >>>  }
> >>>  
> >>>  static inline bool no_fggc_candidate(struct f2fs_sb_info *sbi,
> >>> -                        unsigned int secno)
> >>> +                        unsigned int secno, struct victim_sel_policy *p)
> >>>  {
> >>> -    if (get_valid_blocks(sbi, GET_SEG_FROM_SEC(sbi, secno), true) >=
> >>> -                        sbi->fggc_threshold)
> >>> +    unsigned int cur_cost;
> >>> +
> >>> +    cur_cost = get_valid_blocks(sbi, GET_SEG_FROM_SEC(sbi, secno), true);
> >>> +    if (cur_cost >= sbi->fggc_threshold) {
> >>> +        if (p->min_cost_r > cur_cost) {
> >>> +            p->min_cost_r = cur_cost;
> >>> +            p->min_segno_r = p->cur_segno_r;
> >>> +        }
> >>>          return true;
> >>> +    }
> >>> +
> >>>      return false;
> >>>  }
> >>>  
> >>> --
> >>> 1.8.5.2
> > .
> >
> 
> 
> -- 
> Thanks,
> Yunlong Song
>

[toc] | [prev] | [next] | [standalone]

#1694568

FromYunlong Song <yunlong.song@huawei.com>
Date2017-07-24 11:30 +0200
Message-ID<u6HQB-2Si-1@gated-at.bofh.it>
In reply to#1693986
Hi Jay,
     fggc_threshold is 507, reserved_segment is 462.

On 2017/7/22 5:07, Jaegeuk Kim wrote:
> Hi Yunlong,
>
> On 07/20, Yunlong Song wrote:
>> Hi, Jay,
>>      The distribution is like this, unit is segment counts:
>>      cnt_free: 0 (free blocks)
>>      cnt_full: 25182 (segment which has 512 blocks)
>>      cnt_over: 25192 (segment which valid blocks over fggc_threshold)
>>      cnt_below: 870 (segment which valid blocks below fggc_threshold)
> What are the values of fggc_threshold and ovp ratio or reserved_segments?
> How was the proc/segment_info?
>
> Thanks,
>
>> The test is fragment test, add and delete small files over and over.
>>
>> On 2017/7/18 0:56, Jaegeuk Kim wrote:
>>> On 07/16, sylinux wrote:
>>>> In fact，this is not "suppose" case yet, we have already met this problem several times in some test suits for corner case, or I cannot notice that this could happen.
>>> So, have you taken a look at distribution of valid blocks in that case?
>>> I'm wondering what distribution can cause this.
>>>
>>> Thanks,
>>>
>>>>
>>>>
>>>> 发自网易邮箱大师
>>>> On 07/16/2017 09:09, Jaegeuk Kim wrote:
>>>> Hi Yunlong,
>>>>
>>>> On 07/14, Yunlong Song wrote:
>>>>> Suppose that the valid blocks of each section are all over sbi->fggc_threshold,
>>>> How about adding a kernel message first to detect your *supposed* sceanrio?
>>>> If that happens, it'll be a sort of bug which we haven't assumed.
>>>>
>>>> Thanks,
>>>>
>>>>> and even has_not_enough_free_secs is true, f2fs_gc cannot do its job since the
>>>>> no_fggc_candidate always returns true. As a result, the reserved segments can be
>>>>> used up, and finally there is no free segment at all, and get_new_segment cannot
>>>>> get a free segment, filesystem will trap into a wrong status.
>>>>>
>>>>> To fix this, we record the segno which has a rough minimum cost and return it to
>>>>> __get_victim to continue f2fs_gc's job.
>>>>>
>>>>> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
>>>>> ---
>>>>>   fs/f2fs/gc.c      | 19 ++++++++++++++-----
>>>>>   fs/f2fs/segment.h | 17 ++++++++++++++---
>>>>>   2 files changed, 28 insertions(+), 8 deletions(-)
>>>>>
>>>>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>>>>> index fa3d2e2..965e783 100644
>>>>> --- a/fs/f2fs/gc.c
>>>>> +++ b/fs/f2fs/gc.c
>>>>> @@ -178,6 +178,8 @@ static void select_policy(struct f2fs_sb_info *sbi, int gc_type,
>>>>>           p->offset = 0;
>>>>>       else
>>>>>           p->offset = SIT_I(sbi)->last_victim[p->gc_mode];
>>>>> +
>>>>> +    p->min_cost_r = UINT_MAX;
>>>>>   }
>>>>>   
>>>>>   static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
>>>>> @@ -194,7 +196,7 @@ static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
>>>>>           return 0;
>>>>>   }
>>>>>   
>>>>> -static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
>>>>> +static unsigned int check_bg_victims(struct f2fs_sb_info *sbi, struct victim_sel_policy *p)
>>>>>   {
>>>>>       struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
>>>>>       unsigned int secno;
>>>>> @@ -208,11 +210,12 @@ static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
>>>>>           if (sec_usage_check(sbi, secno))
>>>>>               continue;
>>>>>   
>>>>> -        if (no_fggc_candidate(sbi, secno))
>>>>> +        p->cur_segno_r = GET_SEG_FROM_SEC(sbi, secno);
>>>>> +        if (no_fggc_candidate(sbi, secno, p))
>>>>>               continue;
>>>>>   
>>>>>           clear_bit(secno, dirty_i->victim_secmap);
>>>>> -        return GET_SEG_FROM_SEC(sbi, secno);
>>>>> +        return p->cur_segno_r;
>>>>>       }
>>>>>       return NULL_SEGNO;
>>>>>   }
>>>>> @@ -332,7 +335,7 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
>>>>>   
>>>>>       last_victim = sm->last_victim[p.gc_mode];
>>>>>       if (p.alloc_mode == LFS && gc_type == FG_GC) {
>>>>> -        p.min_segno = check_bg_victims(sbi);
>>>>> +        p.min_segno = check_bg_victims(sbi, &p);
>>>>>           if (p.min_segno != NULL_SEGNO)
>>>>>               goto got_it;
>>>>>       }
>>>>> @@ -369,8 +372,9 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
>>>>>               goto next;
>>>>>           if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap))
>>>>>               goto next;
>>>>> +        p.cur_segno_r = segno;
>>>>>           if (gc_type == FG_GC && p.alloc_mode == LFS &&
>>>>> -                    no_fggc_candidate(sbi, secno))
>>>>> +                    no_fggc_candidate(sbi, secno, &p))
>>>>>               goto next;
>>>>>   
>>>>>           cost = get_gc_cost(sbi, segno, &p);
>>>>> @@ -403,6 +407,11 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi,
>>>>>           trace_f2fs_get_victim(sbi->sb, type, gc_type, &p,
>>>>>                   sbi->cur_victim_sec,
>>>>>                   prefree_segments(sbi), free_segments(sbi));
>>>>> +    } else if (has_not_enough_free_secs(sbi, 0, 0)) {
>>>>> +        p.min_segno = p.min_segno_r;
>>>>> +        if (p.alloc_mode == LFS && gc_type == FG_GC)
>>>>> +            clear_bit(GET_SEC_FROM_SEG(sbi, p.min_segno), dirty_i->victim_secmap);
>>>>> +        goto got_it;
>>>>>       }
>>>>>   out:
>>>>>       mutex_unlock(&dirty_i->seglist_lock);
>>>>> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
>>>>> index 6b871b4..7d2d0f3 100644
>>>>> --- a/fs/f2fs/segment.h
>>>>> +++ b/fs/f2fs/segment.h
>>>>> @@ -169,6 +169,9 @@ struct victim_sel_policy {
>>>>>       unsigned int ofs_unit;        /* bitmap search unit */
>>>>>       unsigned int min_cost;        /* minimum cost */
>>>>>       unsigned int min_segno;        /* segment # having min. cost */
>>>>> +    unsigned int min_cost_r;        /* rough minimum cost */
>>>>> +    unsigned int min_segno_r;        /* segment # having rough min. cost */
>>>>> +    unsigned int cur_segno_r;        /* segment # rough process is handling */
>>>>>   };
>>>>>   
>>>>>   struct seg_entry {
>>>>> @@ -743,11 +746,19 @@ static inline block_t sum_blk_addr(struct f2fs_sb_info *sbi, int base, int type)
>>>>>   }
>>>>>   
>>>>>   static inline bool no_fggc_candidate(struct f2fs_sb_info *sbi,
>>>>> -                        unsigned int secno)
>>>>> +                        unsigned int secno, struct victim_sel_policy *p)
>>>>>   {
>>>>> -    if (get_valid_blocks(sbi, GET_SEG_FROM_SEC(sbi, secno), true) >=
>>>>> -                        sbi->fggc_threshold)
>>>>> +    unsigned int cur_cost;
>>>>> +
>>>>> +    cur_cost = get_valid_blocks(sbi, GET_SEG_FROM_SEC(sbi, secno), true);
>>>>> +    if (cur_cost >= sbi->fggc_threshold) {
>>>>> +        if (p->min_cost_r > cur_cost) {
>>>>> +            p->min_cost_r = cur_cost;
>>>>> +            p->min_segno_r = p->cur_segno_r;
>>>>> +        }
>>>>>           return true;
>>>>> +    }
>>>>> +
>>>>>       return false;
>>>>>   }
>>>>>   
>>>>> --
>>>>> 1.8.5.2
>>> .
>>>
>>
>> -- 
>> Thanks,
>> Yunlong Song
>>
> .
>

-- 
Thanks,
Yunlong Song

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web