Before this patchset: root@(none)$ insmod bench_page_pool_simple.ko [ 323.367627] bench_page_pool_simple: Loaded [ 323.448747] time_bench: Type:for_loop Per elem: 0 cycles(tsc) 0.769 ns (step:0) - (measurement period time:0.076997150 sec time_interval:76997150) - (invoke count:100000000 tsc_interval:7699707) [ 324.812884] time_bench: Type:atomic_inc Per elem: 1 cycles(tsc) 13.468 ns (step:0) - (measurement period time:1.346855130 sec time_interval:1346855130) - (invoke count:100000000 tsc_interval:134685507) [ 324.980875] time_bench: Type:lock Per elem: 1 cycles(tsc) 15.010 ns (step:0) - (measurement period time:0.150101270 sec time_interval:150101270) - (invoke count:10000000 tsc_interval:15010120) [ 325.652195] time_bench: Type:rcu Per elem: 0 cycles(tsc) 6.542 ns (step:0) - (measurement period time:0.654213000 sec time_interval:654213000) - (invoke count:100000000 tsc_interval:65421294) [ 325.669215] bench_page_pool_simple: time_bench_page_pool01_fast_path(): Cannot use page_pool fast-path [ 325.974848] time_bench: Type:no-softirq-page_pool01 Per elem: 2 cycles(tsc) 29.633 ns (step:0) - (measurement period time:0.296338200 sec time_interval:296338200) - (invoke count:10000000 tsc_interval:29633814) [ 325.993517] bench_page_pool_simple: time_bench_page_pool02_ptr_ring(): Cannot use page_pool fast-path [ 326.576636] time_bench: Type:no-softirq-page_pool02 Per elem: 5 cycles(tsc) 57.391 ns (step:0) - (measurement period time:0.573911820 sec time_interval:573911820) - (invoke count:10000000 tsc_interval:57391174) [ 326.595307] bench_page_pool_simple: time_bench_page_pool03_slow(): Cannot use page_pool fast-path [ 328.422661] time_bench: Type:no-softirq-page_pool03 Per elem: 18 cycles(tsc) 181.849 ns (step:0) - (measurement period time:1.818495880 sec time_interval:1818495880) - (invoke count:10000000 tsc_interval:181849581) [ 328.441681] bench_page_pool_simple: pp_tasklet_handler(): in_serving_softirq fast-path [ 328.449584] bench_page_pool_simple: time_bench_page_pool01_fast_path(): in_serving_softirq fast-path [ 328.755031] time_bench: Type:tasklet_page_pool01_fast_path Per elem: 2 cycles(tsc) 29.632 ns (step:0) - (measurement period time:0.296327910 sec time_interval:296327910) - (invoke count:10000000 tsc_interval:29632785) [ 328.774308] bench_page_pool_simple: time_bench_page_pool02_ptr_ring(): in_serving_softirq fast-path [ 329.578579] time_bench: Type:tasklet_page_pool02_ptr_ring Per elem: 7 cycles(tsc) 79.523 ns (step:0) - (measurement period time:0.795236560 sec time_interval:795236560) - (invoke count:10000000 tsc_interval:79523650) [ 329.597769] bench_page_pool_simple: time_bench_page_pool03_slow(): in_serving_softirq fast-path [ 331.507501] time_bench: Type:tasklet_page_pool03_slow Per elem: 19 cycles(tsc) 190.104 ns (step:0) - (measurement period time:1.901047510 sec time_interval:1901047510) - (invoke count:10000000 tsc_interval:190104743) After this patchset: root@(none)$ insmod bench_page_pool_simple.ko [ 138.634758] bench_page_pool_simple: Loaded [ 138.715879] time_bench: Type:for_loop Per elem: 0 cycles(tsc) 0.769 ns (step:0) - (measurement period time:0.076972720 sec time_interval:76972720) - (invoke count:100000000 tsc_interval:7697265) [ 140.079897] time_bench: Type:atomic_inc Per elem: 1 cycles(tsc) 13.467 ns (step:0) - (measurement period time:1.346735370 sec time_interval:1346735370) - (invoke count:100000000 tsc_interval:134673531) [ 140.247841] time_bench: Type:lock Per elem: 1 cycles(tsc) 15.005 ns (step:0) - (measurement period time:0.150055080 sec time_interval:150055080) - (invoke count:10000000 tsc_interval:15005497) [ 140.919072] time_bench: Type:rcu Per elem: 0 cycles(tsc) 6.541 ns (step:0) - (measurement period time:0.654125000 sec time_interval:654125000) - (invoke count:100000000 tsc_interval:65412493) [ 140.936091] bench_page_pool_simple: time_bench_page_pool01_fast_path(): Cannot use page_pool fast-path [ 141.246985] time_bench: Type:no-softirq-page_pool01 Per elem: 3 cycles(tsc) 30.159 ns (step:0) - (measurement period time:0.301598160 sec time_interval:301598160) - (invoke count:10000000 tsc_interval:30159812) [ 141.265654] bench_page_pool_simple: time_bench_page_pool02_ptr_ring(): Cannot use page_pool fast-path [ 141.976265] time_bench: Type:no-softirq-page_pool02 Per elem: 7 cycles(tsc) 70.140 ns (step:0) - (measurement period time:0.701405780 sec time_interval:701405780) - (invoke count:10000000 tsc_interval:70140573) [ 141.994933] bench_page_pool_simple: time_bench_page_pool03_slow(): Cannot use page_pool fast-path [ 144.018945] time_bench: Type:no-softirq-page_pool03 Per elem: 20 cycles(tsc) 201.514 ns (step:0) - (measurement period time:2.015141210 sec time_interval:2015141210) - (invoke count:10000000 tsc_interval:201514113) [ 144.037966] bench_page_pool_simple: pp_tasklet_handler(): in_serving_softirq fast-path [ 144.045870] bench_page_pool_simple: time_bench_page_pool01_fast_path(): in_serving_softirq fast-path [ 144.205045] time_bench: Type:tasklet_page_pool01_fast_path Per elem: 1 cycles(tsc) 15.005 ns (step:0) - (measurement period time:0.150056510 sec time_interval:150056510) - (invoke count:10000000 tsc_interval:15005645) [ 144.224320] bench_page_pool_simple: time_bench_page_pool02_ptr_ring(): in_serving_softirq fast-path [ 144.916044] time_bench: Type:tasklet_page_pool02_ptr_ring Per elem: 6 cycles(tsc) 68.269 ns (step:0) - (measurement period time:0.682693070 sec time_interval:682693070) - (invoke count:10000000 tsc_interval:68269300) [ 144.935234] bench_page_pool_simple: time_bench_page_pool03_slow(): in_serving_softirq fast-path [ 146.997684] time_bench: Type:tasklet_page_pool03_slow Per elem: 20 cycles(tsc) 205.376 ns (step:0) - (measurement period time:2.053766310 sec time_interval:2053766310) - (invoke count:10000000 tsc_interval:205376624) 1. https://lore.kernel.org/lkml/8067f204-1380-4d37-8ffd-007fc6f26738@xxxxxxxxxx/T/ CC: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx> CC: Robin Murphy <robin.murphy@xxxxxxx> CC: Alexander Duyck <alexander.duyck@xxxxxxxxx> CC: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> CC: IOMMU <iommu@xxxxxxxxxxxxxxx> CC: MM <linux-mm@xxxxxxxxx> Change log: V6: 1. Repost based on latest net-next. 2. Rename page_pool_to_pp() to page_pool_get_pp(). V5: 1. Support unlimit inflight pages. 2. Add some optimization to avoid the overhead of fixing bug. V4: 1. use scanning to do the unmapping 2. spilt dma sync skipping into separate patch V3: 1. Target net-next tree instead of net tree. 2. Narrow the rcu lock as the discussion in v2. 3. Check the ummapping cnt against the inflight cnt. V2: 1. Add a item_full stat. 2. Use container_of() for page_pool_to_pp(). Yunsheng Lin (8): page_pool: introduce page_pool_get_pp() API page_pool: fix timing for checking and disabling napi_local page_pool: fix IOMMU crash when driver has already unbound page_pool: support unlimited number of inflight pages page_pool: skip dma sync operation for inflight pages page_pool: use list instead of ptr_ring for ring cache page_pool: batch refilling pages to reduce atomic operation page_pool: use list instead of array for alloc cache drivers/net/ethernet/freescale/fec_main.c | 8 +- .../ethernet/google/gve/gve_buffer_mgmt_dqo.c | 2 +- drivers/net/ethernet/intel/iavf/iavf_txrx.c | 6 +- drivers/net/ethernet/intel/idpf/idpf_txrx.c | 14 +- drivers/net/ethernet/intel/libeth/rx.c | 2 +- .../net/ethernet/mellanox/mlx5/core/en/xdp.c | 3 +- drivers/net/netdevsim/netdev.c | 6 +- drivers/net/wireless/mediatek/mt76/mt76.h | 2 +- include/linux/mm_types.h | 2 +- include/linux/skbuff.h | 1 + include/net/libeth/rx.h | 3 +- include/net/netmem.h | 24 +- include/net/page_pool/helpers.h | 11 + include/net/page_pool/types.h | 63 +- net/core/devmem.c | 4 +- net/core/netmem_priv.h | 5 +- net/core/page_pool.c | 660 ++++++++++++++---- net/core/page_pool_priv.h | 12 +- 18 files changed, 664 insertions(+), 164 deletions(-) -- 2.33.0