[PlanetCCRMA] 3ms latency in ccrma kernel

Sat Apr 23 11:02:09 PDT 2016

On 04/23/2016 12:56 AM, Jiri Kastner wrote:
> seems ccrma kernel has disabled rt at all :)

Hey, good catch! Which exact kernel on which Fedora version?

There must be something messed up in the build process for the one you 
have installed, in my laptop (with a test kernel) I have this:

$ grep PREEMPT_RT /boot/config-4.4.6-200.rt14.1.fc22.ccrma.x86_64+rt |more
CONFIG_PREEMPT_RT_BASE=y
# CONFIG_PREEMPT_RTB is not set
CONFIG_PREEMPT_RT_FULL=y

Thanks for the report and detective work!...
Sorry for the slow response to this thread, this week has been a killer.
(I don't have access to my fc23 laptop right now)
-- Fernando

> see bellow:
>
> --- config-ccrma.sorted	2016-04-23 09:47:08.175969867 +0200
> +++ config-rt.sorted	2016-04-23 09:47:25.856547548 +0200
> @@ -581,7 +581,6 @@
>   CONFIG_CPU_FREQ=y
>   CONFIG_CPU_IDLE_GOV_MENU=y
>   CONFIG_CPU_IDLE=y
> -CONFIG_CPUMASK_OFFSTACK=y
>   CONFIG_CPU_RMAP=y
>   CONFIG_CPUSETS=y
>   CONFIG_CPU_SUP_AMD=y
> @@ -1345,6 +1344,7 @@
>   CONFIG_HAVE_PERF_EVENTS=y
>   CONFIG_HAVE_PERF_REGS=y
>   CONFIG_HAVE_PERF_USER_STACK_DUMP=y
> +CONFIG_HAVE_PREEMPT_LAZY=y
>   CONFIG_HAVE_REGS_AND_STACK_ACCESS_API=y
>   CONFIG_HAVE_SETUP_PER_CPU_AREA=y
>   CONFIG_HAVE_SYSCALL_TRACEPOINTS=y
> @@ -1506,6 +1506,7 @@
>   CONFIG_HVC_XEN_FRONTEND=y
>   CONFIG_HVC_XEN=y
>   CONFIG_HW_CONSOLE=y
> +CONFIG_HWLAT_DETECTOR=m
>   CONFIG_HWMON_VID=m
>   CONFIG_HWMON=y
>   CONFIG_HWPOISON_INJECT=m
> @@ -1660,11 +1661,6 @@
>   CONFIG_INFINIBAND_USNIC=m
>   CONFIG_INIT_ENV_ARG_LIMIT=32
>   CONFIG_INITRAMFS_SOURCE=""
> -CONFIG_INLINE_READ_UNLOCK_IRQ=y
> -CONFIG_INLINE_READ_UNLOCK=y
> -CONFIG_INLINE_SPIN_UNLOCK_IRQ=y
> -CONFIG_INLINE_WRITE_UNLOCK_IRQ=y
> -CONFIG_INLINE_WRITE_UNLOCK=y
>   CONFIG_INOTIFY_USER=y
>   CONFIG_INPUT_APANEL=m
>   CONFIG_INPUT_ATI_REMOTE2=m
> @@ -2006,7 +2002,6 @@
>   CONFIG_JOYSTICK_XPAD_LEDS=y
>   CONFIG_JOYSTICK_XPAD=m
>   CONFIG_JOYSTICK_ZHENHUA=m
> -CONFIG_JUMP_LABEL=y
>   CONFIG_KALLSYMS_ALL=y
>   CONFIG_KALLSYMS=y
>   CONFIG_KARMA_PARTITION=y
> @@ -2113,7 +2108,6 @@
>   CONFIG_LOCKDEP_SUPPORT=y
>   CONFIG_LOCKD=m
>   CONFIG_LOCKD_V4=y
> -CONFIG_LOCK_SPIN_ON_OWNER=y
>   CONFIG_LOCKUP_DETECTOR=y
>   CONFIG_LOG_BUF_SHIFT=18
>   CONFIG_LOG_CPU_MAX_BUF_SHIFT=12
> @@ -2282,6 +2276,7 @@
>   CONFIG_MISDN_NETJET=m
>   CONFIG_MISDN_SPEEDFAX=m
>   CONFIG_MISDN_W6692=m
> +CONFIG_MISSED_TIMER_OFFSETS_HIST=y
>   CONFIG_MKISS=m
>   CONFIG_MLX4_CORE=m
>   CONFIG_MLX4_DEBUG=y
> @@ -2374,7 +2369,6 @@
>   CONFIG_MTRR_SANITIZER=y
>   CONFIG_MTRR=y
>   CONFIG_MULTIUSER=y
> -CONFIG_MUTEX_SPIN_ON_OWNER=y
>   CONFIG_MVMDIO=m
>   CONFIG_MWAVE=m
>   CONFIG_MWIFIEX=m
> @@ -2880,12 +2874,9 @@
>   CONFIG_OPENVSWITCH_GRE=m
>   CONFIG_OPENVSWITCH=m
>   CONFIG_OPENVSWITCH_VXLAN=m
> -CONFIG_OPROFILE_EVENT_MULTIPLEX=y
> -CONFIG_OPROFILE=m
>   CONFIG_OPROFILE_NMI_TIMER=y
>   CONFIG_OPT3001=m
>   CONFIG_OPTIMIZE_INLINING=y
> -CONFIG_OPTPROBES=y
>   CONFIG_ORE=m
>   CONFIG_ORINOCO_USB=m
>   CONFIG_OSF_PARTITION=y
> @@ -3054,8 +3045,13 @@
>   CONFIG_PPS_CLIENT_PARPORT=m
>   CONFIG_PPS=m
>   CONFIG_PPTP=m
> +CONFIG_PREEMPT_COUNT=y
> +CONFIG_PREEMPT_LAZY=y
>   CONFIG_PREEMPT_NOTIFIERS=y
> -CONFIG_PREEMPT_VOLUNTARY=y
> +CONFIG_PREEMPT_RCU=y
> +CONFIG_PREEMPT_RT_BASE=y
> +CONFIG_PREEMPT_RT_FULL=y
> +CONFIG_PREEMPT=y
>   CONFIG_PREVENT_FIRMWARE_BUILD=y
>   CONFIG_PRINTER=m
>   CONFIG_PRINTK_TIME=y
> @@ -3156,7 +3152,6 @@
>   CONFIG_RFKILL_LEDS=y
>   CONFIG_RFKILL=m
>   CONFIG_RFS_ACCEL=y
> -CONFIG_RING_BUFFER_ALLOW_SWAP=y
>   CONFIG_RING_BUFFER_BENCHMARK=m
>   CONFIG_RING_BUFFER=y
>   CONFIG_ROCKER=m
> @@ -3286,8 +3281,7 @@
>   CONFIG_RTLWIFI_PCI=m
>   CONFIG_RTLWIFI_USB=m
>   CONFIG_RT_MUTEXES=y
> -CONFIG_RWSEM_SPIN_ON_OWNER=y
> -CONFIG_RWSEM_XCHGADD_ALGORITHM=y
> +CONFIG_RWSEM_GENERIC_SPINLOCK=y
>   CONFIG_S2IO=m
>   CONFIG_SAMSUNG_LAPTOP=m
>   CONFIG_SAMSUNG_Q10=m
> @@ -3622,7 +3616,6 @@
>   CONFIG_SLIP_COMPRESSED=y
>   CONFIG_SLIP=m
>   CONFIG_SLIP_SMART=y
> -CONFIG_SLUB_CPU_PARTIAL=y
>   CONFIG_SLUB_DEBUG=y
>   CONFIG_SLUB=y
>   CONFIG_SMARTJOYPLUS_FF=y
> @@ -4067,9 +4060,6 @@
>   CONFIG_TRACER_SNAPSHOT=y
>   CONFIG_TRACING_SUPPORT=y
>   CONFIG_TRACING=y
> -CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y
> -CONFIG_TRANSPARENT_HUGEPAGE=y
> -CONFIG_TREE_RCU=y
>   CONFIG_TRUSTED_KEYS=m
>   CONFIG_TTPCI_EEPROM=m
>   CONFIG_TTY=y
> @@ -4531,6 +4521,7 @@
>   CONFIG_W83627HF_WDT=m
>   CONFIG_W83877F_WDT=m
>   CONFIG_W83977F_WDT=m
> +CONFIG_WAKEUP_LATENCY_HIST=y
>   CONFIG_WANT_DEV_COREDUMP=y
>   CONFIG_WATCHDOG_CORE=y
>   CONFIG_WATCHDOG=y
> @@ -4594,7 +4585,6 @@
>   CONFIG_X86_PMEM_LEGACY_DEVICE=y
>   CONFIG_X86_PMEM_LEGACY=y
>   CONFIG_X86_PM_TIMER=y
> -CONFIG_X86_POWERNOW_K8=m
>   CONFIG_X86_PTDUMP_CORE=y
>   CONFIG_X86_PTDUMP=y
>   CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS=y
>
> _______________________________________________
> PlanetCCRMA mailing list
> PlanetCCRMA at ccrma.stanford.edu
> https://cm-mail.stanford.edu/mailman/listinfo/planetccrma
>