Paolo Abeni dbae2b0628 net: skb: introduce and use a single page frag cache ... After commit 3226b158e6 ("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 fd9ea57f4e ("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 <eric.dumazet@gmail.com> Suggested-by: Alexander H Duyck <alexanderduyck@fb.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Alexander Duyck <alexanderduyck@fb.com> Link: https://lore.kernel.org/r/6b6f65957c59f86a353fc09a5127e83a32ab5999.1664350652.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>		2022-09-29 18:48:15 -07:00
..
acpi	Merge branch 'acpi-properties'	2022-08-11 19:21:03 +02:00
asm-generic	arm64 fixes for -rc7	2022-09-23 15:28:51 -07:00
clocksource
crypto	for-5.20/block-2022-08-04	2022-08-04 20:00:14 -07:00
drm	drm/edid: Handle EDID 1.4 range descriptor h/vfreq offsets	2022-09-02 16:38:51 +03:00
dt-bindings	power supply and reset changes for the v6.0 series	2022-08-12 09:37:33 -07:00
keys
kunit	kunit: fix assert_type for comparison macros	2022-09-01 13:00:32 -06:00
kvm
linux	net: skb: introduce and use a single page frag cache	2022-09-29 18:48:15 -07:00
math-emu
media	SPDX changes for 6.0-rc1	2022-08-04 12:12:54 -07:00
memory
misc
net	net: Fix incorrect address comparison when searching for a bind2 bucket	2022-09-28 18:52:17 -07:00
pcmcia
ras	mm, hwpoison: enable memory error handling on 1GB hugepage	2022-08-08 18:06:44 -07:00
rdma	dma-mapping updates	2022-08-06 10:56:45 -07:00
rv
scsi	scsi: core: Fix a use-after-free	2022-09-01 01:02:10 -04:00
soc	net: dsa: felix: add support for changing DSA master	2022-09-20 10:32:36 +02:00
sound
target
trace	ARM: SoC fixes for 6.0-rc6	2022-09-22 11:10:11 -07:00
uapi	docs: netlink: clarify the historical baggage of Netlink flags	2022-09-29 18:39:39 -07:00
ufs	scsi: ufs: core: Enable link lost interrupt	2022-08-11 22:04:32 -04:00
vdso
video
xen	x86/xen: Add support for HVMOP_set_evtchn_upcall_vector	2022-08-12 11:28:21 +02:00