linux/include
Neal Cardwell 8919a9b31e tcp: Only init congestion control if not initialized already
Change tcp_init_transfer() to only initialize congestion control if it
has not been initialized already.

With this new approach, we can arrange things so that if the EBPF code
sets the congestion control by calling setsockopt(TCP_CONGESTION) then
tcp_init_transfer() will not re-initialize the CC module.

This is an approach that has the following beneficial properties:

(1) This allows CC module customizations made by the EBPF called in
    tcp_init_transfer() to persist, and not be wiped out by a later
    call to tcp_init_congestion_control() in tcp_init_transfer().

(2) Does not flip the order of EBPF and CC init, to avoid causing bugs
    for existing code upstream that depends on the current order.

(3) Does not cause 2 initializations for for CC in the case where the
    EBPF called in tcp_init_transfer() wants to set the CC to a new CC
    algorithm.

(4) Allows follow-on simplifications to the code in net/core/filter.c
    and net/ipv4/tcp_cong.c, which currently both have some complexity
    to special-case CC initialization to avoid double CC
    initialization if EBPF sets the CC.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Kevin Yang <yyd@google.com>
Cc: Lawrence Brakmo <brakmo@fb.com>
2020-09-10 20:53:01 -07:00
..
acpi ACPI updates for 5.9-rc1 2020-08-03 20:37:22 -07:00
asm-generic iomap: constify ioreadX() iomem argument (as in generic implementation) 2020-08-14 19:56:57 -07:00
clocksource include/: replace HTTP links with HTTPS ones 2020-08-12 10:57:59 -07:00
crypto mm, treewide: rename kzfree() to kfree_sensitive() 2020-08-07 11:33:22 -07:00
drm Linux 5.8 2020-08-11 11:58:31 +10:00
dt-bindings Here's some more updates that missed the last pull request because I 2020-08-12 12:19:49 -07:00
keys It's been a busy cycle for documentation - hopefully the busiest for a 2020-08-04 22:47:54 -07:00
kunit
kvm
linux bpf: Plug hole in struct bpf_sk_lookup_kern 2020-09-10 17:47:50 -07:00
math-emu
media media updates for v5.9-rc1 2020-08-07 13:00:53 -07:00
memory
misc
net tcp: Only init congestion control if not initialized already 2020-09-10 20:53:01 -07:00
pcmcia
ras
rdma RDMA 5.9 merge window pull request 2020-08-06 16:43:36 -07:00
scsi
soc include/: replace HTTP links with HTTPS ones 2020-08-12 10:57:59 -07:00
sound ALSA: hda: Add dma stop delay variable 2020-08-05 12:27:47 +02:00
target scsi: target: Make iscsit_register_transport() return void 2020-08-04 20:56:56 -04:00
trace Improvements to ext4's block allocator performance for very large file 2020-08-21 11:03:38 -07:00
uapi bpf: Fix comment for helper bpf_current_task_under_cgroup() 2020-09-10 20:04:51 -07:00
vdso lib/vdso: Allow to add architecture-specific vdso data 2020-08-06 10:57:30 +02:00
video
xen xen: branch for v5.9-rc1b 2020-08-14 13:34:37 -07:00