>-----Original Message----- >From: Jaegeuk Kim [mailto:jaeg...@kernel.org] >Sent: Friday, April 20, 2018 11:41 AM >To: Yuchao (T) >Cc: heyunlei; linux-f2fs-devel@lists.sourceforge.net; Wangbintian; >Zhangdianfang (Euler) >Subject: Re: [f2fs-dev][PATCH v2] f2fs: use cur_map instead of ckpt_map > >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()?
Discards issued after do_checkpoint: i. new cp write ok, discard will not affect recovery ii. new cp write failed(including power-cut), discards will be released, will not affet recovery too? Anything I missing? Thanks. > >> >> - 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
