user/sven/linux.git/include/linux/netdevice.h, branch v6.1.16

net: add atomic_long_t to net_device_stats fields

2022-12-31T12:33:02Z

[ Upstream commit 6c1c5097781f563b70a81683ea6fdac21637573b ] Long standing KCSAN issues are caused by data-race around some dev->stats changes. Most performance critical paths already use per-cpu variables, or per-queue ones. It is reasonable (and more correct) to use atomic operations for the slow paths. This patch adds an union for each field of net_device_stats, so that we can convert paths that are not yet protected by a spinlock or a mutex. netdev_stats_to_stats64() no longer has an #if BITS_PER_LONG==64 Note that the memcpy() we were using on 64bit arches had no provision to avoid load-tearing, while atomic_long_read() is providing the needed protection at no cost. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

Revert "net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and}"

2022-10-15T10:17:12Z

This reverts commit 854701ba4c39afae2362ba19a580c461cb183e4f. We have more violations around, which leads to: WARNING: CPU: 2 PID: 1 at include/linux/cpumask.h:110 __netif_set_xps_queue+0x14e/0x770 Let's back this out and retry with a larger clean up in -next. Fixes: 854701ba4c39 ("net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and}") Link: https://lore.kernel.org/all/20221014030459.3272206-2-guoren@kernel.org/ Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

Merge tag 'bitmap-6.1-rc1' of https://github.com/norov/linux

2022-10-10T19:49:34Z

Pull bitmap updates from Yury Norov: - Fix unsigned comparison to -1 in CPUMAP_FILE_MAX_BYTES (Phil Auld) - cleanup nr_cpu_ids vs nr_cpumask_bits mess (me) This series cleans that mess and adds new config FORCE_NR_CPUS that allows to optimize cpumask subsystem if the number of CPUs is known at compile-time. - optimize find_bit() functions (me) Reworks find_bit() functions based on new FIND_{FIRST,NEXT}_BIT() macros. - add find_nth_bit() (me) Adds find_nth_bit(), which is ~70 times faster than bitcounting with for_each() loop: for_each_set_bit(bit, mask, size) if (n-- == 0) return bit; Also adds bitmap_weight_and() to let people replace this pattern: tmp = bitmap_alloc(nbits); bitmap_and(tmp, map1, map2, nbits); weight = bitmap_weight(tmp, nbits); bitmap_free(tmp); with a single bitmap_weight_and() call. - repair cpumask_check() (me) After switching cpumask to use nr_cpu_ids, cpumask_check() started generating many false-positive warnings. This series fixes it. - Add for_each_cpu_andnot() and for_each_cpu_andnot() (Valentin Schneider) Extends the API with one more function and applies it in sched/core. * tag 'bitmap-6.1-rc1' of https://github.com/norov/linux: (28 commits) sched/core: Merge cpumask_andnot()+for_each_cpu() into for_each_cpu_andnot() lib/test_cpumask: Add for_each_cpu_and(not) tests cpumask: Introduce for_each_cpu_andnot() lib/find_bit: Introduce find_next_andnot_bit() cpumask: fix checking valid cpu range lib/bitmap: add tests for for_each() loops lib/find: optimize for_each() macros lib/bitmap: introduce for_each_set_bit_wrap() macro lib/find_bit: add find_next{,_and}_bit_wrap cpumask: switch for_each_cpu{,_not} to use for_each_bit() net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and} cpumask: add cpumask_nth_{,and,andnot} lib/bitmap: remove bitmap_ord_to_pos lib/bitmap: add tests for find_nth_bit() lib: add find_nth{,_and,_andnot}_bit() lib/bitmap: add bitmap_weight_and() lib/bitmap: don't call __bitmap_weight() in kernel code tools: sync find_bit() implementation lib/find_bit: optimize find_next_bit() functions lib/find_bit: create find_first_zero_bit_le() ...

net: fix cpu_max_bits_warn() usage in netif_attrmask_next{,_and}

2022-10-01T17:22:57Z

The functions require to be passed with a cpu index prior to one that is the first to start search, so the valid input range is [-1, nr_cpu_ids-1). However, the code checks against [-1, nr_cpu_ids). Acked-by: Jakub Kicinski Signed-off-by: Yury Norov

net/sched: query offload capabilities through ndo_setup_tc()

2022-09-30T01:52:01Z

When adding optional new features to Qdisc offloads, existing drivers must reject the new configuration until they are coded up to act on it. Since modifying all drivers in lockstep with the changes in the Qdisc can create problems of its own, it would be nice if there existed an automatic opt-in mechanism for offloading optional features. Jakub proposes that we multiplex one more kind of call through ndo_setup_tc(): one where the driver populates a Qdisc-specific capability structure. First user will be taprio in further changes. Here we are introducing the definitions for the base functionality. Link: https://patchwork.kernel.org/project/netdevbpf/patch/20220923163310.3192733-3-vladimir.oltean@nxp.com/ Suggested-by: Jakub Kicinski Co-developed-by: Jakub Kicinski Signed-off-by: Vladimir Oltean Signed-off-by: Jakub Kicinski

net: skb: introduce and use a single page frag cache

2022-09-30T01:48:15Z

After commit 3226b158e67c ("net: avoid 32 x truesize under-estimation for tiny skbs") we are observing 10-20% regressions in performance tests with small packets. The perf trace points to high pressure on the slab allocator. This change tries to improve the allocation schema for small packets using an idea originally suggested by Eric: a new per CPU page frag is introduced and used in __napi_alloc_skb to cope with small allocation requests. To ensure that the above does not lead to excessive truesize underestimation, the frag size for small allocation is inflated to 1K and all the above is restricted to build with 4K page size. Note that we need to update accordingly the run-time check introduced with commit fd9ea57f4e95 ("net: add napi_get_frags_check() helper"). Alex suggested a smart page refcount schema to reduce the number of atomic operations and deal properly with pfmemalloc pages. Under small packet UDP flood, I measure a 15% peak tput increases. Suggested-by: Eric Dumazet Suggested-by: Alexander H Duyck Signed-off-by: Paolo Abeni Reviewed-by: Eric Dumazet Reviewed-by: Alexander Duyck Link: https://lore.kernel.org/r/6b6f65957c59f86a353fc09a5127e83a32ab5999.1664350652.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski

net: drop the weight argument from netif_napi_add

2022-09-29T01:57:14Z

We tell driver developers to always pass NAPI_POLL_WEIGHT as the weight to netif_napi_add(). This may be confusing to newcomers, drop the weight argument, those who really need to tweak the weight can use netif_napi_add_weight(). Acked-by: Marc Kleine-Budde # for CAN Link: https://lore.kernel.org/r/20220927132753.750069-1-kuba@kernel.org Signed-off-by: Jakub Kicinski

net: introduce iterators over synced hw addresses

2022-09-20T08:32:35Z

Some network drivers use __dev_mc_sync()/__dev_uc_sync() and therefore program the hardware only with addresses with a non-zero sync_cnt. Some of the above drivers also need to save/restore the address filtering lists when certain events happen, and they need to walk through the struct net_device :: uc and struct net_device :: mc lists. But these lists contain unsynced addresses too. To keep the appearance of an elementary form of data encapsulation, provide iterators through these lists that only look at entries with a non-zero sync_cnt, instead of filtering entries out from device drivers. Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: Paolo Abeni

net: remove netif_tx_napi_add()

2022-09-02T11:41:43Z

All callers are now gone. Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

net: bql: add more documentation

2022-09-02T11:27:46Z

Add some documentation for netdev_tx_sent_queue() and netdev_tx_completed_queue() Stating that netdev_tx_completed_queue() must be called once per TX completion round is apparently not obvious for everybody. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller