In preparation to limiting the scope of a list iterator to the list traversal loop, use a dedicated pointer to iterate through the list [1].
Since that variable should not be used past the loop iteration, a separate variable is used to 'remember the current location within the loop'. To either continue iterating from that position or start a new iteration (if the previous iteration was complete) list_prepare_entry() is used. Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=ehreask5sqxpwr9y7k9sa6cwx...@mail.gmail.com/ [1] Signed-off-by: Jakob Koschel <jakobkosc...@gmail.com> --- fs/gfs2/lops.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c index 6ba51cbb94cf..74e6d05cee2c 100644 --- a/fs/gfs2/lops.c +++ b/fs/gfs2/lops.c @@ -653,7 +653,7 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit, bool is_databuf) { struct gfs2_log_descriptor *ld; - struct gfs2_bufdata *bd1 = NULL, *bd2; + struct gfs2_bufdata *bd1 = NULL, *bd2, *tmp1, *tmp2; struct page *page; unsigned int num; unsigned n; @@ -661,7 +661,7 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit, gfs2_log_lock(sdp); list_sort(NULL, blist, blocknr_cmp); - bd1 = bd2 = list_prepare_entry(bd1, blist, bd_list); + tmp1 = tmp2 = list_prepare_entry(bd1, blist, bd_list); while(total) { num = total; if (total > limit) @@ -675,14 +675,18 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit, ptr = (__be64 *)(ld + 1); n = 0; + bd1 = list_prepare_entry(tmp1, blist, bd_list); + tmp1 = NULL; list_for_each_entry_continue(bd1, blist, bd_list) { *ptr++ = cpu_to_be64(bd1->bd_bh->b_blocknr); if (is_databuf) { gfs2_check_magic(bd1->bd_bh); *ptr++ = cpu_to_be64(buffer_escaped(bd1->bd_bh) ? 1 : 0); } - if (++n >= num) + if (++n >= num) { + tmp1 = bd1; break; + } } gfs2_log_unlock(sdp); @@ -690,6 +694,8 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit, gfs2_log_lock(sdp); n = 0; + bd2 = list_prepare_entry(tmp2, blist, bd_list); + tmp2 = NULL; list_for_each_entry_continue(bd2, blist, bd_list) { get_bh(bd2->bd_bh); gfs2_log_unlock(sdp); @@ -712,8 +718,10 @@ static void gfs2_before_commit(struct gfs2_sbd *sdp, unsigned int limit, gfs2_log_write_bh(sdp, bd2->bd_bh); } gfs2_log_lock(sdp); - if (++n >= num) + if (++n >= num) { + tmp2 = bd2; break; + } } BUG_ON(total < num); base-commit: f82da161ea75dc4db21b2499e4b1facd36dab275 -- 2.25.1
