On 2015/9/8 19:14, Chao Yu wrote: > Hi Yunlei, > >> -----Original Message----- >> From: Yunlei He [mailto:[email protected]] >> Sent: Tuesday, September 08, 2015 6:51 PM >> To: [email protected]; [email protected]; >> [email protected] >> Cc: [email protected]; Yunlei He >> Subject: [f2fs-dev] [PATCH] f2fs: add a judgment in add_discard_addrs >> >> CP_DISCARD traverse all segments in fstrim_range to add small discards, >> it is better to select entry->len bigger than trim_minlen. > > If we mount with 'discard' option, f2fs will trigger real-time discard > when do checkpoint. If we add judgment condition here, fragmented invalid > blocks will not be discarded since we stop adding them in pending list > through __add_discard_entry.
This judgment condition is only valid for cp reason CP_DISCARD, and has no influence to other checkpoint. The process of fstrim adds all invalid blocks in pending list and deletes entries which len < trim_minlen when issue discard. Can we do the selection when added? Thanks, > > Thanks, > >> >> Signed-off-by: Yunlei He <[email protected]> >> --- >> fs/f2fs/segment.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c >> index 78e6d06..a0dab7a 100644 >> --- a/fs/f2fs/segment.c >> +++ b/fs/f2fs/segment.c >> @@ -599,7 +599,8 @@ static void add_discard_addrs(struct f2fs_sb_info *sbi, >> struct cp_control >> *cpc) >> break; >> >> end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1); >> - __add_discard_entry(sbi, cpc, se, start, end); >> + if(force && cpc->trim_minlen >= (end - start)) >> + __add_discard_entry(sbi, cpc, se, start, end); >> } >> } >> >> -- >> 1.9.1 > > > ------------------------------------------------------------------------------ _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
