linux/tools
John Kacur 01b05fc0e5 rtla/timerlat: Fix histogram report when a cpu count is 0
On short runs it is possible to get no samples on a cpu, like this:

  # rtla timerlat hist -u -T50

  Index   IRQ-001   Thr-001   Usr-001   IRQ-002   Thr-002   Usr-002
  2             1         0         0         0         0         0
  33            0         1         0         0         0         0
  36            0         0         1         0         0         0
  49            0         0         0         1         0         0
  52            0         0         0         0         1         0
  over:         0         0         0         0         0         0
  count:        1         1         1         1         1         0
  min:          2        33        36        49        52 18446744073709551615
  avg:          2        33        36        49        52         -
  max:          2        33        36        49        52         0
  rtla timerlat hit stop tracing
    IRQ handler delay:		(exit from idle)	    48.21 us (91.09 %)
    IRQ latency:						    49.11 us
    Timerlat IRQ duration:				     2.17 us (4.09 %)
    Blocking thread:					     1.01 us (1.90 %)
  	               swapper/2:0        		     1.01 us
  ------------------------------------------------------------------------
    Thread latency:					    52.93 us (100%)

  Max timerlat IRQ latency from idle: 49.11 us in cpu 2

Note, the value 18446744073709551615 is the same as ~0.

Fix this by reporting no results for the min, avg and max if the count
is 0.

Link: https://lkml.kernel.org/r/20240510190318.44295-1-jkacur@redhat.com

Cc: stable@vger.kernel.org
Fixes: 1eeb6328e8 ("rtla/timerlat: Add timerlat hist mode")
Suggested-by: Daniel Bristot de Oliveria <bristot@kernel.org>
Signed-off-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
2024-05-16 16:45:40 +02:00
..
accounting
arch tools/include: Sync arm64 asm/cputype.h with the kernel sources 2024-04-11 10:38:29 -07:00
bootconfig
bpf libbpf, selftests/bpf: Adjust libbpf, bpftool, selftests to match LLVM 2024-03-15 14:24:00 -07:00
build
certs
cgroup
counter
crypto
debugging
firewire
firmware
gpio
hv hv/hv_kvp_daemon: Handle IPv4 and Ipv6 combination for keyfile format 2024-04-10 21:25:40 +00:00
iio
include perf tools fixes for v6.9 2024-04-19 16:34:10 -07:00
kvm/kvm_stat
laptop
leds
lib bpf-for-netdev 2024-03-26 12:55:18 +01:00
memory-model
mm
net/ynl tools: ynl: don't ignore errors in NLMSG_DONE messages 2024-04-23 15:37:33 +02:00
objtool objtool: Fix compile failure when using the x32 compiler 2024-03-30 22:12:37 +01:00
pci
pcmcia
perf RISC-V Fixes for 6.9-rc6 2024-04-27 12:02:55 -07:00
power Turbostat version 2024.04.10 2024-04-10 13:13:27 -07:00
rcu
scripts
spi
testing Fix Kselftest's vfork() side effects 2024-05-12 13:01:59 -07:00
thermal
time
tracing rtla/timerlat: Fix histogram report when a cpu count is 0 2024-05-16 16:45:40 +02:00
usb
verification tools/verification: Use tools/build makefiles on rv 2024-03-20 05:39:06 +01:00
virtio tools: virtio: introduce vhost_net_test 2024-03-05 11:38:14 +01:00
wmi
workqueue
Makefile tools/Makefile: remove cgroup target 2024-03-26 11:07:21 -07:00