android_kernel_motorola_sm6375/include
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Eric Dumazet 131287ff83 once: add DO_ONCE_SLOW() for sleepable contexts
[ Upstream commit 62c07983bef9d3e78e71189441e1a470f0d1e653 ]

Christophe Leroy reported a ~80ms latency spike
happening at first TCP connect() time.

This is because __inet_hash_connect() uses get_random_once()
to populate a perturbation table which became quite big
after commit 4c2c8f03a5ab ("tcp: increase source port perturb table to 2^16")

get_random_once() uses DO_ONCE(), which block hard irqs for the duration
of the operation.

This patch adds DO_ONCE_SLOW() which uses a mutex instead of a spinlock
for operations where we prefer to stay in process context.

Then __inet_hash_connect() can use get_random_slow_once()
to populate its perturbation table.

Fixes: 4c2c8f03a5ab ("tcp: increase source port perturb table to 2^16")
Fixes: 190cc82489f4 ("tcp: change source port randomizarion at connect() time")
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/netdev/CANn89iLAEYBaoYajy0Y9UmGFff5GPxDUoG-ErVB2jDdRNQ5Tug@mail.gmail.com/T/#t
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26 13:22:27 +02:00
..
acpi ACPI: CPPC: Do not prevent CPPC from working in the future 2022-08-25 11:18:15 +02:00
asm-generic asm-generic: sections: refactor memory_intersects 2022-09-05 10:27:43 +02:00
clocksource
crypto crypto: drbg - make reseeding from get_random_bytes() synchronous 2022-06-22 14:11:18 +02:00
drm drm: fix EDID struct for old ARM OABI format 2022-06-14 18:11:31 +02:00
dt-bindings
keys
kvm
linux once: add DO_ONCE_SLOW() for sleepable contexts 2022-10-26 13:22:27 +02:00
math-emu
media media: subdev: disallow ioctl for saa6588/davinci 2021-07-19 08:53:17 +02:00
misc
net tcp: fix tcp_cwnd_validate() to not forget is_cwnd_limited 2022-10-26 13:22:26 +02:00
pcmcia
ras
rdma RDMA/netlink: Add __maybe_unused to static inline in C file 2021-11-26 10:47:18 +01:00
scsi scsi: stex: Properly zero out the passthrough command structure 2022-10-15 07:54:39 +02:00
soc
sound ALSA: core: Add async signal helpers 2022-08-25 11:18:37 +02:00
target scsi: target: Fix ordered tag handling 2021-11-26 10:47:16 +01:00
trace spmi: trace: fix stack-out-of-bound access in SPMI tracing functions 2022-08-25 11:18:11 +02:00
uapi can: error: specify the values of data[5..7] of CAN error frames 2022-08-25 11:17:47 +02:00
vdso
video video: of_display_timing.h: include errno.h 2022-07-12 16:30:47 +02:00
xen xen/gnttab: fix gnttab_end_foreign_access() without page specified 2022-03-11 11:22:39 +01:00