On 04/20, Chao Yu wrote: > On 2018/4/20 11:26, Jaegeuk Kim wrote: > > On 04/20, heyunlei wrote: > >> > >> > >>> -----Original Message----- > >>> From: Yuchao (T) > >>> Sent: Friday, April 13, 2018 9:12 AM > >>> To: Jaegeuk Kim; heyunlei > >>> Cc: linux-f2fs-devel@lists.sourceforge.net; Wangbintian; Zhangdianfang > >>> (Euler) > >>> Subject: Re: [f2fs-dev][PATCH v2] f2fs: use cur_map instead of ckpt_map > >>> > >>> On 2018/4/13 6:37, Jaegeuk Kim wrote: > >>>> On 04/10, Yunlei He wrote: > >>>>> In flush_sit_entries::add_discard_addrs path, cur_map and ckpt_map > >>>>> are the same, but in exist_trim_candidates::add_discard_addrs, > >>>>> cur_map is updated one, and newer than ckpt_map, so we need to use > >>>>> cur_map to check whether there are discard candidates. > >>>>> > >>>>> v1->v2: one problem of check discard candidates reported by Chao, > >>>>> besides, update commit message. > >>>>> > >>>>> Signed-off-by: Yunlei He <heyun...@huawei.com> > >>>>> --- > >>>>> fs/f2fs/segment.c | 2 +- > >>>>> 1 file changed, 1 insertion(+), 1 deletion(-) > >>>>> > >>>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > >>>>> index 5854cc4..f5d0499 100644 > >>>>> --- a/fs/f2fs/segment.c > >>>>> +++ b/fs/f2fs/segment.c > >>>>> @@ -1559,7 +1559,7 @@ static bool add_discard_addrs(struct f2fs_sb_info > >>>>> *sbi, struct cp_control *cpc, > >>>>> > >>>>> /* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned > >>>>> long) */ > >>>>> for (i = 0; i < entries; i++) > >>>>> - dmap[i] = force ? ~ckpt_map[i] & ~discard_map[i] : > >>>>> + dmap[i] = force ? ~cur_map[i] & ~discard_map[i] : > >>>> > >>>> NAK. We're able to loose data for roll-forward recovery. > >> Ping > >> > >> Thanks. > >>> > >>> Actually, in fstrim flow (force == 1), cur_map is complete the same as > >>> ckpt_map. > >>> Do you suffer data corruption during testing this patch? > > > > So, we don't need this patch, IIUC. > > No, in precheck flow, we haven't flush cur_map to ckpt_map, so they are > different.
Then, what if power-cut happens between exist_trim_candidates() and do_checkpoint()? > > - fstrim > - exist_trim_candidates > - add_discard_addrs > > > > >>> > >>> Thanks, > >>> > >>>> > >>>>> (cur_map[i] ^ ckpt_map[i]) & > >>>>> ckpt_map[i]; > >>>>> > >>>>> while (force || SM_I(sbi)->dcc_info->nr_discards <= > >>>>> -- > >>>>> 1.9.1 > >>>> > >>>> . > >>>> > > > > . > > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
