linux/include
Aananth V 3868ab0f19 tcp: new TCP_INFO stats for RTO events
The 2023 SIGCOMM paper "Improving Network Availability with Protective
ReRoute" has indicated Linux TCP's RTO-triggered txhash rehashing can
effectively reduce application disruption during outages. To better
measure the efficacy of this feature, this patch adds three more
detailed stats during RTO recovery and exports via TCP_INFO.
Applications and monitoring systems can leverage this data to measure
the network path diversity and end-to-end repair latency during network
outages to improve their network infrastructure.

The following counters are added to tcp_sock in order to track RTO
events over the lifetime of a TCP socket.

1. u16 total_rto - Counts the total number of RTO timeouts.
2. u16 total_rto_recoveries - Counts the total number of RTO recoveries.
3. u32 total_rto_time - Counts the total time spent (ms) in RTO
                        recoveries. (time spent in CA_Loss and
                        CA_Recovery states)

To compute total_rto_time, we add a new u32 rto_stamp field to
tcp_sock. rto_stamp records the start timestamp (ms) of the last RTO
recovery (CA_Loss).

Corresponding fields are also added to the tcp_info struct.

Signed-off-by: Aananth V <aananthv@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-16 13:42:34 +01:00
..
acpi Merge branches 'acpi-scan', 'acpi-tad', 'acpi-extlog' and 'acpi-misc' 2023-08-25 20:49:52 +02:00
asm-generic ata changes for 6.6 2023-09-05 12:37:28 -07:00
clocksource
crypto This update includes the following changes: 2023-08-29 11:23:29 -07:00
drm drm for 6.6-rc1 2023-08-30 13:34:34 -07:00
dt-bindings IOMMU Updates for Linux v6.6 2023-09-01 16:54:25 -07:00
keys integrity: PowerVM support for loading third party code signing keys 2023-08-17 20:12:35 +00:00
kunit - An extensive rework of kexec and crash Kconfig from Eric DeVolder 2023-08-29 14:53:51 -07:00
kvm KVM: arm64: pmu: Guard PMU emulation definitions with CONFIG_KVM 2023-08-23 20:01:03 +01:00
linux tcp: new TCP_INFO stats for RTO events 2023-09-16 13:42:34 +01:00
math-emu
media media updates for v6.6-rc1 2023-09-01 12:21:32 -07:00
memory
misc
net ipv6: lockless IPV6_FLOWINFO_SEND implementation 2023-09-15 10:33:48 +01:00
pcmcia
ras
rdma RDMA Remove unused function declarations 2023-08-13 10:32:35 +03:00
rv rv: Set variable 'da_mon_##name' to static 2023-09-01 21:00:00 -04:00
scsi SCSI misc on 20230909 2023-09-09 12:01:33 -07:00
soc IOMMU Updates for Linux v6.6 2023-09-01 16:54:25 -07:00
sound ASoC: Name iov_iter argument as iterator instead of buffer 2023-09-01 15:38:49 +02:00
target
trace tracing: Replace strlcpy with strscpy in trace/events/task.h 2023-09-01 21:00:00 -04:00
uapi tcp: new TCP_INFO stats for RTO events 2023-09-16 13:42:34 +01:00
ufs Merge branch 'fixes' into misc 2023-09-02 08:25:19 +01:00
vdso
video fbdev: kyro: Remove unused declarations 2023-08-15 23:39:33 +02:00
xen dma-maping updates for Linux 6.6 2023-08-29 20:32:10 -07:00