[upstream commit d46edd671a147032e22cfeb271a5734703093649]
Currently, sysctl kernel.bpf_stats_enabled controls BPF runtime stats.
Typical userspace tools use kernel.bpf_stats_enabled as follows:
1. Enable kernel.bpf_stats_enabled;
2. Check program run_time_ns;
3. Sleep for the monitoring period;
4. Check program run_time_ns again, calculate the difference;
5. Disable kernel.bpf_stats_enabled.
The problem with this approach is that only one userspace tool can toggle
this sysctl. If multiple tools toggle the sysctl at the same time, the
measurement may be inaccurate.
To fix this problem while keep backward compatibility, introduce a new
bpf command BPF_ENABLE_STATS. On success, this command enables stats and
returns a valid fd. BPF_ENABLE_STATS takes argument "type". Currently,
only one type, BPF_STATS_RUN_TIME, is supported. We can extend the
command to support other types of stats in the future.
With BPF_ENABLE_STATS, user space tool would have the following flow:
1. Get a fd with BPF_ENABLE_STATS, and make sure it is valid;
2. Check program run_time_ns;
3. Sleep for the monitoring period;
4. Check program run_time_ns again, calculate the difference;
5. Close the fd.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200430071506.1408910-2-songliubraving@fb.com
Accumulate unused quota from previous periods, thus accumulated
bandwidth runtime can be used in the following periods. During
accumulation, take care of runtime overflow. Previous non-burstable
CFS bandwidth controller only assign quota to runtime, that saves a lot.
A sysctl parameter cpu_qos_cfs_bw_burst_enabled is introduced as a
switch for burst. It is disabled by default.
Signed-off-by: Huaixin Chang <changhuaixin@linux.alibaba.com>
Signed-off-by: Shanpei Chen <shanpeic@linux.alibaba.com>
add quota aware support when showing container
cpuinfo and stat information.
Signed-off-by: caelli <caelli@tencent.com>
Reviewed-by: Peng Hao <flyingpeng@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
Providing back up buffer for Quality Monitor, can be used to catch key
context when abnormal jitters occur. And application can also use it
to detect system env exception.
Signed-off-by: Bauerchen <bauerchen@tencent.com>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Bin Lai <robinlai@tencent.com>
[ Upstream commit 3b3376f222e3ab58367d9dd405cafd09d5e37b7c ]
Apart from subsystem specific .proc_handler handler, all ctl_tables with
extra1 and extra2 members set should use proc_dointvec_minmax instead of
proc_dointvec, or the limit set in extra* never work and potentially echo
underflow values(negative numbers) is likely make system unstable.
Especially vfs_cache_pressure and zone_reclaim_mode, -1 is apparently not
a valid value, but we can set to them. And then kernel may crash.
# echo -1 > /proc/sys/vm/vfs_cache_pressure
Link: https://lkml.kernel.org/r/20201223105535.2875-1-linf@wangsu.com
Signed-off-by: Lin Feng <linf@wangsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
In the virtualization scenario, you can use pvipi to optimize the sending of
IPI interrupts and reduce the number of vmexit.
rps_using_pvipi test
Test guest: 32 core, 64G memory, virtio-net 8 queues, rss interrupt is bound
to 24-31 core. Observe the number of vmexit of 31 cores.
1. 1000000pps
100 iperf instances, 10000pps per instance.
disable rps_using_pvipi 68077 vmexit/s
enable rps_using_pvipi 21138 vmexit/s
2. 2000000pps
1000 iperf instances, 2000pps per instance.
disable rps_using_pvipi 40879 vmexit/s
enable rps_using_pvipi 9195 vmexit/s
3. 2000000pps
2000 iperf instances, 1000pps per instance.
disable rps_using_pvipi 24746 vmexit/s
enable rps_using_pvipi 7292 vmexit/s
Enabling rps_using_pvipi can greatly reduce the number of vmexit.
Signed-off-by: yongduan <yongduan@tencent.com>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
In the virtualization scenario, you can use pvipi to optimize the sending of
IPI interrupts and reduce the number of vmexit.
rps_using_pvipi test
Test guest: 32 core, 64G memory, virtio-net 8 queues, rss interrupt is bound
to 24-31 core. Observe the number of vmexit of 31 cores.
1. 1000000pps
100 iperf instances, 10000pps per instance.
disable rps_using_pvipi 68077 vmexit/s
enable rps_using_pvipi 21138 vmexit/s
2. 2000000pps
1000 iperf instances, 2000pps per instance.
disable rps_using_pvipi 40879 vmexit/s
enable rps_using_pvipi 9195 vmexit/s
3. 2000000pps
2000 iperf instances, 1000pps per instance.
disable rps_using_pvipi 24746 vmexit/s
enable rps_using_pvipi 7292 vmexit/s
Enabling rps_using_pvipi can greatly reduce the number of vmexit.
Signed-off-by: yongduan <yongduan@tencent.com>
Reviewed-by: Jiang Biao <benbjiang@tencent.com>
Song Liu