On 2016/9/25 2:10, Jaegeuk Kim wrote: > On Sat, Sep 24, 2016 at 11:32:08AM +0800, Chao Yu wrote: >> On 2016/9/24 8:52, Jaegeuk Kim wrote: >>> On Sat, Sep 24, 2016 at 08:46:54AM +0800, Chao Yu wrote: >>>> Hi Jaegeuk, >>>> >>>> On 2016/9/24 7:53, Jaegeuk Kim wrote: >>>>> Hi Chao, >>>>> >>>>> The basic rule is to stop every operations once CP_ERROR_FLAG is set. >>>>> But, this patch simply breaks the rule. >>>>> For example, f2fs_write_data_page() currently exits with >>>>> mapping_set_error(). >>>>> So this patch incurs missing dentry blocks in a valid checkpoint. >>>> >>>> Yes, that's right. >>>> >>>> How about triggering checkpoint error in f2fs_stop_checkpoint? >>> >>> Let's just use src/godown in xfstests, since we don't need to trigger this >>> multiple times in runtime. >> >> After we inject checkpoint error into f2fs at first time, all write IOs will >> be >> refused to be writebacked to storage, meanwhile read IOs can continuously go >> through f2fs, so with checkpoint error injection being supported, we can >> support >> to trigger random analogously power off by f2fs itself, instead of using >> tools. >> It means it doesn't needs specified test cases where we must use godown >> ioctl, >> but with normal testcases in xfstest/fsstress/lkp, in CP error injection >> enabled >> f2fs, we can test power off cases. > > But, in this approach, the test coverage would be quite limited. > In my testcase, I'm randomly injecting godown while fsstress is running, which > mimics really random power failures, as I believe. I'm running this infinitely > with fscking at every run. > > Anyway, in order to do this without godown, how about background_gc thread to > trigger f2fs_stop_checkpoint?
Yeap, better. What do you think of adding random f2fs_stop_checkpoint in f2fs_balance_fs? power off can be triggered if gc thread is not running. Thanks, > >> >> Thanks, > > . >
