* [PATCH] f2fs: let background GC being aware of freezing
@ 2017-07-21 3:36 Chao Yu
2017-07-21 20:54 ` Jaegeuk Kim
0 siblings, 1 reply; 3+ messages in thread
From: Chao Yu @ 2017-07-21 3:36 UTC (permalink / raw)
To: jaegeuk; +Cc: linux-f2fs-devel, linux-kernel, chao, Chao Yu
When ->freeze_fs is called from lvm for doing snapshot, it needs to
make sure there will be no more changes in filesystem's data, however,
previously, background GC wasn't aware of freezing, so in environment
with active background GC thread, data of snapshot becomes unstable.
This patch fixes this issue by adding sb_{start,end}_intwrite in GC
flow.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
---
fs/f2fs/gc.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 76ad2c3d88db..1c0117f60083 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -55,6 +55,8 @@ static int gc_thread_func(void *data)
}
#endif
+ sb_start_intwrite(sbi->sb);
+
/*
* [GC triggering condition]
* 0. GC is not conducted currently.
@@ -69,12 +71,12 @@ static int gc_thread_func(void *data)
* So, I'd like to wait some time to collect dirty segments.
*/
if (!mutex_trylock(&sbi->gc_mutex))
- continue;
+ goto next;
if (!is_idle(sbi)) {
increase_sleep_time(gc_th, &wait_ms);
mutex_unlock(&sbi->gc_mutex);
- continue;
+ goto next;
}
if (has_enough_invalid_blocks(sbi))
@@ -93,6 +95,8 @@ static int gc_thread_func(void *data)
/* balancing f2fs's metadata periodically */
f2fs_balance_fs_bg(sbi);
+next:
+ sb_end_intwrite(sbi->sb);
} while (!kthread_should_stop());
return 0;
--
2.13.1.388.g69e6b9b4f4a9
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] f2fs: let background GC being aware of freezing
2017-07-21 3:36 [PATCH] f2fs: let background GC being aware of freezing Chao Yu
@ 2017-07-21 20:54 ` Jaegeuk Kim
2017-07-22 0:47 ` Chao Yu
0 siblings, 1 reply; 3+ messages in thread
From: Jaegeuk Kim @ 2017-07-21 20:54 UTC (permalink / raw)
To: Chao Yu; +Cc: linux-f2fs-devel, linux-kernel, chao
Hi Chao,
On 07/21, Chao Yu wrote:
> When ->freeze_fs is called from lvm for doing snapshot, it needs to
> make sure there will be no more changes in filesystem's data, however,
> previously, background GC wasn't aware of freezing, so in environment
> with active background GC thread, data of snapshot becomes unstable.
What about flush/discard threads?
Thanks,
>
> This patch fixes this issue by adding sb_{start,end}_intwrite in GC
> flow.
>
> Signed-off-by: Chao Yu <yuchao0@huawei.com>
> ---
> fs/f2fs/gc.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 76ad2c3d88db..1c0117f60083 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -55,6 +55,8 @@ static int gc_thread_func(void *data)
> }
> #endif
>
> + sb_start_intwrite(sbi->sb);
> +
> /*
> * [GC triggering condition]
> * 0. GC is not conducted currently.
> @@ -69,12 +71,12 @@ static int gc_thread_func(void *data)
> * So, I'd like to wait some time to collect dirty segments.
> */
> if (!mutex_trylock(&sbi->gc_mutex))
> - continue;
> + goto next;
>
> if (!is_idle(sbi)) {
> increase_sleep_time(gc_th, &wait_ms);
> mutex_unlock(&sbi->gc_mutex);
> - continue;
> + goto next;
> }
>
> if (has_enough_invalid_blocks(sbi))
> @@ -93,6 +95,8 @@ static int gc_thread_func(void *data)
>
> /* balancing f2fs's metadata periodically */
> f2fs_balance_fs_bg(sbi);
> +next:
> + sb_end_intwrite(sbi->sb);
>
> } while (!kthread_should_stop());
> return 0;
> --
> 2.13.1.388.g69e6b9b4f4a9
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] f2fs: let background GC being aware of freezing
2017-07-21 20:54 ` Jaegeuk Kim
@ 2017-07-22 0:47 ` Chao Yu
0 siblings, 0 replies; 3+ messages in thread
From: Chao Yu @ 2017-07-22 0:47 UTC (permalink / raw)
To: Jaegeuk Kim, Chao Yu; +Cc: linux-f2fs-devel, linux-kernel
Hi Jaegeuk,
On 2017/7/22 4:54, Jaegeuk Kim wrote:
> Hi Chao,
>
> On 07/21, Chao Yu wrote:
>> When ->freeze_fs is called from lvm for doing snapshot, it needs to
>> make sure there will be no more changes in filesystem's data, however,
>> previously, background GC wasn't aware of freezing, so in environment
>> with active background GC thread, data of snapshot becomes unstable.
>
> What about flush/discard threads?
Updated.
Thanks,
>
> Thanks,
>
>>
>> This patch fixes this issue by adding sb_{start,end}_intwrite in GC
>> flow.
>>
>> Signed-off-by: Chao Yu <yuchao0@huawei.com>
>> ---
>> fs/f2fs/gc.c | 8 ++++++--
>> 1 file changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
>> index 76ad2c3d88db..1c0117f60083 100644
>> --- a/fs/f2fs/gc.c
>> +++ b/fs/f2fs/gc.c
>> @@ -55,6 +55,8 @@ static int gc_thread_func(void *data)
>> }
>> #endif
>>
>> + sb_start_intwrite(sbi->sb);
>> +
>> /*
>> * [GC triggering condition]
>> * 0. GC is not conducted currently.
>> @@ -69,12 +71,12 @@ static int gc_thread_func(void *data)
>> * So, I'd like to wait some time to collect dirty segments.
>> */
>> if (!mutex_trylock(&sbi->gc_mutex))
>> - continue;
>> + goto next;
>>
>> if (!is_idle(sbi)) {
>> increase_sleep_time(gc_th, &wait_ms);
>> mutex_unlock(&sbi->gc_mutex);
>> - continue;
>> + goto next;
>> }
>>
>> if (has_enough_invalid_blocks(sbi))
>> @@ -93,6 +95,8 @@ static int gc_thread_func(void *data)
>>
>> /* balancing f2fs's metadata periodically */
>> f2fs_balance_fs_bg(sbi);
>> +next:
>> + sb_end_intwrite(sbi->sb);
>>
>> } while (!kthread_should_stop());
>> return 0;
>> --
>> 2.13.1.388.g69e6b9b4f4a9
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2017-07-22 0:48 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-07-21 3:36 [PATCH] f2fs: let background GC being aware of freezing Chao Yu
2017-07-21 20:54 ` Jaegeuk Kim
2017-07-22 0:47 ` Chao Yu
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).