| Message ID | 20240604042454.2012091-1-alexs@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | use folio in ksm | expand |
On 04.06.24 06:24, alexs@kernel.org wrote: > From: "Alex Shi (tencent)" <alexs@kernel.org> > > This is the 2nd part to use folio in ksm, it saves 82kbytes in ksm.o and > passed all ksm testcases in kselftest. > > KSM still split same folios to single page if they are good to be KSM, > but will skip the rest subpage checking if a folio couldn't suit for > ksm. > > Alex Shi (tencent) (10): > mm/ksm: reduce the flush action for ksm merging page > mm/ksm: skip subpages of compound pages > mm/ksm: use folio in try_to_merge_one_page > mm/ksm: add identical_folio func > mm/ksm: use folio in stable_tree_search > mm/ksm: remove page_stable_node > mm/ksm: use folio in unstable_tree_search_insert > mm/ksm: use folio in try_to_merge_xx serie funcs > mm/ksm: calc_checksum for folio > m/ksm: use folio in ksm scan path I skimmed over most patches, but I'm afraid you introduce quite some subtle problems. Part of the rework should not be do convert things to folios that really operate on pages (of possibly large folios). We really have to be careful about pages vs. folios before we have KSM folios. Only then, we know that we have small folios only.
On 6/4/24 9:28 PM, David Hildenbrand wrote: > On 04.06.24 06:24, alexs@kernel.org wrote: >> From: "Alex Shi (tencent)" <alexs@kernel.org> >> >> This is the 2nd part to use folio in ksm, it saves 82kbytes in ksm.o and >> passed all ksm testcases in kselftest. >> >> KSM still split same folios to single page if they are good to be KSM, >> but will skip the rest subpage checking if a folio couldn't suit for >> ksm. >> >> Alex Shi (tencent) (10): >> mm/ksm: reduce the flush action for ksm merging page >> mm/ksm: skip subpages of compound pages >> mm/ksm: use folio in try_to_merge_one_page >> mm/ksm: add identical_folio func >> mm/ksm: use folio in stable_tree_search >> mm/ksm: remove page_stable_node >> mm/ksm: use folio in unstable_tree_search_insert >> mm/ksm: use folio in try_to_merge_xx serie funcs >> mm/ksm: calc_checksum for folio >> m/ksm: use folio in ksm scan path > > I skimmed over most patches, but I'm afraid you introduce quite some subtle problems. > > Part of the rework should not be do convert things to folios that really operate on pages (of possibly large folios). > > We really have to be careful about pages vs. folios before we have KSM folios. Only then, we know that we have small folios only. > Thanks a lot for your reviewing and comments. Let's if we'd do it better with your comments! :) Thanks Alex
From: "Alex Shi (tencent)" <alexs@kernel.org> This is the 2nd part to use folio in ksm, it saves 82kbytes in ksm.o and passed all ksm testcases in kselftest. KSM still split same folios to single page if they are good to be KSM, but will skip the rest subpage checking if a folio couldn't suit for ksm. Alex Shi (tencent) (10): mm/ksm: reduce the flush action for ksm merging page mm/ksm: skip subpages of compound pages mm/ksm: use folio in try_to_merge_one_page mm/ksm: add identical_folio func mm/ksm: use folio in stable_tree_search mm/ksm: remove page_stable_node mm/ksm: use folio in unstable_tree_search_insert mm/ksm: use folio in try_to_merge_xx serie funcs mm/ksm: calc_checksum for folio m/ksm: use folio in ksm scan path include/linux/mm.h | 17 ++++ mm/ksm.c | 230 +++++++++++++++++++++++---------------------- 2 files changed, 135 insertions(+), 112 deletions(-)