V2: - dropped the get_pfnblock_migratetype() optimization patchlet since somebody else beat me to it (thanks Zi) - broke out pcp bypass fix since somebody else reported the bug: https://lore.kernel.org/linux-mm/20230911181108.GA104295@xxxxxxxxxxx/ - fixed the CONFIG_UNACCEPTED_MEMORY build (lkp) - rebased to v6.6-rc1 The series is based on v6.6-rc1 plus the pcp bypass fix above ^ --- This is a breakout series from the huge page allocator patches[1]. While testing and benchmarking the series incrementally, as per reviewer request, it became apparent that there are several sources of freelist migratetype violations that later patches in the series hid. Those violations occur when pages of one migratetype end up on the freelists of another type. This encourages incompatible page mixing down the line, where allocation requests ask for one migrate type, but receives pages of another. This defeats the mobility grouping. The series addresses those causes. The last patch adds type checks on all freelist movements to rule out any violations. I used these checks to identify the violations fixed up in the preceding patches. The series is a breakout, but has merit on its own: Less type mixing means improved grouping, means less work for compaction, means higher THP success rate and lower allocation latencies. The results can be seen in a mixed workload that stresses the machine with a kernel build job while periodically attempting to allocate batches of THP. The data is averaged over 50 consecutive defconfig builds: VANILLA PATCHED-CLEANLISTS Hugealloc Time median 14642.00 ( +0.00%) 10506.00 ( -28.25%) Hugealloc Time min 4820.00 ( +0.00%) 4783.00 ( -0.77%) Hugealloc Time max 6786868.00 ( +0.00%) 6556624.00 ( -3.39%) Kbuild Real time 240.03 ( +0.00%) 241.45 ( +0.59%) Kbuild User time 1195.49 ( +0.00%) 1195.69 ( +0.02%) Kbuild System time 96.44 ( +0.00%) 97.03 ( +0.61%) THP fault alloc 11490.00 ( +0.00%) 11802.30 ( +2.72%) THP fault fallback 782.62 ( +0.00%) 478.88 ( -38.76%) THP fault fail rate % 6.38 ( +0.00%) 3.90 ( -33.52%) Direct compact stall 297.70 ( +0.00%) 224.56 ( -24.49%) Direct compact fail 265.98 ( +0.00%) 191.56 ( -27.87%) Direct compact success 31.72 ( +0.00%) 33.00 ( +3.91%) Direct compact success rate % 13.11 ( +0.00%) 17.26 ( +29.43%) Compact daemon scanned migrate 1673661.58 ( +0.00%) 1591682.18 ( -4.90%) Compact daemon scanned free 2711252.80 ( +0.00%) 2615217.78 ( -3.54%) Compact direct scanned migrate 384998.62 ( +0.00%) 261689.42 ( -32.03%) Compact direct scanned free 966308.94 ( +0.00%) 667459.76 ( -30.93%) Compact migrate scanned daemon % 80.86 ( +0.00%) 83.34 ( +3.02%) Compact free scanned daemon % 74.41 ( +0.00%) 78.26 ( +5.10%) Alloc stall 338.06 ( +0.00%) 440.72 ( +30.28%) Pages kswapd scanned 1356339.42 ( +0.00%) 1402313.42 ( +3.39%) Pages kswapd reclaimed 581309.08 ( +0.00%) 587956.82 ( +1.14%) Pages direct scanned 56384.18 ( +0.00%) 141095.04 ( +150.24%) Pages direct reclaimed 17055.54 ( +0.00%) 22427.96 ( +31.50%) Pages scanned kswapd % 96.38 ( +0.00%) 93.60 ( -2.86%) Swap out 41528.00 ( +0.00%) 47969.92 ( +15.51%) Swap in 6541.42 ( +0.00%) 9093.30 ( +39.01%) File refaults 127666.50 ( +0.00%) 135766.84 ( +6.34%) include/linux/mm.h | 18 +- include/linux/page-isolation.h | 2 +- include/linux/vmstat.h | 8 - mm/debug_page_alloc.c | 12 +- mm/internal.h | 5 - mm/page_alloc.c | 357 ++++++++++++++++++--------------- mm/page_isolation.c | 23 ++- 7 files changed, 217 insertions(+), 208 deletions(-)
