linux/include
Arjun Roy 18fb76ed53 net-zerocopy: Copy straggler unaligned data for TCP Rx. zerocopy.
When TCP receive zerocopy does not successfully map the entire
requested space, it outputs a 'hint' that the caller should recvmsg().

Augment zerocopy to accept a user buffer that it tries to copy this
hint into - if it is possible to copy the entire hint, it will do so.
This elides a recvmsg() call for received traffic that isn't exactly
page-aligned in size.

This was tested with RPC-style traffic of arbitrary sizes. Normally,
each received message required at least one getsockopt() call, and one
recvmsg() call for the remaining unaligned data.

With this change, almost all of the recvmsg() calls are eliminated,
leading to a savings of about 25%-50% in number of system calls
for RPC-style workloads.

Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-04 13:40:52 -08:00
..
acpi
asm-generic Merge branch 'for-5.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu 2020-11-15 08:57:19 -08:00
clocksource
crypto
drm drm: drm_print.h: fix kernel-doc markups 2020-10-27 11:21:39 +01:00
dt-bindings dt-bindings: firmware: add IMX_SC_R_CAN(x) macro for CAN 2020-11-20 12:06:45 +01:00
keys rxrpc: Don't leak the service-side session key to userspace 2020-11-23 18:09:29 +00:00
kunit kunit: fix display of failed expectations for strings 2020-11-10 13:45:15 -07:00
kvm
linux wireless-drivers-next patches for v5.11 2020-12-04 10:56:37 -08:00
math-emu
media
memory
misc
net Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-12-04 07:48:12 -08:00
pcmcia
ras
rdma net: don't include ethtool.h from netdevice.h 2020-11-23 17:27:04 -08:00
scsi scsi: libiscsi: Fix NOP race condition 2020-11-16 22:32:50 -05:00
soc soc/fsl/qbman: Add an argument to signal if NAPI processing is required. 2020-11-03 17:41:03 -08:00
sound ASoC: Fixes for v5.11 2020-11-19 19:56:29 +01:00
target
trace Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-12-04 07:48:12 -08:00
uapi net-zerocopy: Copy straggler unaligned data for TCP Rx. zerocopy. 2020-12-04 13:40:52 -08:00
vdso
video gpu: ipu-v3: remove unused functions 2020-10-26 10:42:38 +01:00
xen xen: branch for v5.10-rc1c 2020-10-25 10:55:35 -07:00