From: Beethovenklc <beethovenklc@gmail.com>
To: linux-rt-users@vger.kernel.org
Subject: Error using cyclictest's tracing
Date: Sat, 11 Jul 2015 00:57:51 -0300 [thread overview]
Message-ID: <mnq480$9ap$1@ger.gmane.org> (raw)
Hello.
This is my first time posting in this newsgroup, here from Argentina :D
I'm trying to sort out some latency problems on a system with Ubuntu
14.04 LTS, kernel version 3.14.39-rt37 with rt-preempt patch and tracers
enabled and AMD A10-6800K with 4 core of 4GHz CPU.
I'm having problems using cyclictest with -t flag to have more
information regarding unpredictable latency peaks, but it shows an error.
$ sudo ./cyclictest -n -p99 -b200
# /dev/cpu_dma_latency set to 0us
INFO: debugfs mountpoint: /sys/kernel/debug/tracing/
WARN: tracing_enabled or tracing_on not found
debug fs not mounted, TRACERs not configured?
could not set ftrace_enabled to 0
FATAL: Can't open /sys/kernel/debug/tracing/available_tracers for reading
When I list "/sys/kernel/debug" I get
sudo ls /sys/kernel/debug/
acpi dma_buf frontswap kvm-guest regulator virtio-ports
bdi dri gpio mce sched_features wakeup_sources
bluetooth dynamic_debug hid pinctrl sleep_time x86
cleancache eeepc-wmi kprobes pwm suspend_stats
clk extfrag kvm regmap usb
It seems "tracing" folder is not present.. I've read that this folder is
created when you use ftrace. Kernel was compiled with ftrace and tracers
as you can see in my kernel .config file:
$ cat .config | grep _FTRACE
CONFIG_KPROBES_ON_FTRACE=y
CONFIG_HAVE_KPROBES_ON_FTRACE=y
# CONFIG_PSTORE_FTRACE is not set
CONFIG_HAVE_DYNAMIC_FTRACE=y
CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS=y
CONFIG_HAVE_FTRACE_MCOUNT_RECORD=y
CONFIG_FTRACE=y
CONFIG_FTRACE_SYSCALLS=y
CONFIG_DYNAMIC_FTRACE=y
CONFIG_DYNAMIC_FTRACE_WITH_REGS=y
CONFIG_FTRACE_MCOUNT_RECORD=y
# CONFIG_FTRACE_STARTUP_TEST is not set
$ cat .config | grep _TRACE
# CONFIG_TREE_RCU_TRACE is not set
CONFIG_SYSCTL_EXCEPTION_TRACE=y
CONFIG_TRACEPOINTS=y
CONFIG_HAVE_ARCH_TRACEHOOK=y
CONFIG_NETFILTER_XT_TARGET_TRACE=m
# CONFIG_SCSI_IPR_TRACE is not set
# CONFIG_VXGE_DEBUG_TRACE_ALL is not set
# CONFIG_ATH5K_TRACER is not set
CONFIG_CAPI_TRACE=y
CONFIG_TRACE_ROUTER=m
CONFIG_TRACE_SINK=m
CONFIG_TRACE_IRQFLAGS_SUPPORT=y
CONFIG_TRACE_IRQFLAGS=y
# CONFIG_RCU_TRACE is not set
CONFIG_NOP_TRACER=y
CONFIG_HAVE_FUNCTION_TRACER=y
CONFIG_HAVE_FUNCTION_GRAPH_TRACER=y
CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST=y
CONFIG_HAVE_SYSCALL_TRACEPOINTS=y
CONFIG_TRACER_MAX_TRACE=y
CONFIG_TRACE_CLOCK=y
CONFIG_CONTEXT_SWITCH_TRACER=y
CONFIG_GENERIC_TRACER=y
CONFIG_FUNCTION_TRACER=y
CONFIG_FUNCTION_GRAPH_TRACER=y
CONFIG_IRQSOFF_TRACER=y
CONFIG_PREEMPT_TRACER=y
CONFIG_SCHED_TRACER=y
CONFIG_TRACER_SNAPSHOT=y
CONFIG_TRACER_SNAPSHOT_PER_CPU_SWAP=y
CONFIG_STACK_TRACER=y
CONFIG_BLK_DEV_IO_TRACE=y
Did I miss something?
Thanks!
next reply other threads:[~2015-07-11 7:00 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-11 3:57 Beethovenklc [this message]
2015-07-13 10:06 ` Error using cyclictest's tracing Beethovenklc
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