[Xenomai-git] Jan Kiszka : Add INTEL_IDLE to list of problematic config options
Module: xenomai-head Branch: master Commit: 79bbd4d676320c36c7876e568cec90a0a485ee4d URL: http://git.xenomai.org/?p=xenomai-head.git;a=commit;h=79bbd4d676320c36c7876e568cec90a0a485ee4d Author: Jan Kiszka Date: Fri Jan 14 15:43:28 2011 +0100 Add INTEL_IDLE to list of problematic config options See TROUBLESHOOTING for explanation. Signed-off-by: Jan Kiszka --- TROUBLESHOOTING |4 scripts/Kconfig.frag |9 + 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/TROUBLESHOOTING b/TROUBLESHOOTING index 4d84a79..e8d4b53 100644 --- a/TROUBLESHOOTING +++ b/TROUBLESHOOTING @@ -57,6 +57,10 @@ sleep states, increasing latency in ways dependent upon both the BIOS's ACPI tables and code. You may be able to suppress the sleeping with 'idle=poll' boot-arg, test to find out +INTEL_IDLE: Just like ACPI_PROCESSOR, this idle driver sends the CPU +into deep C states, also causing huge latencies because the APIC timer +that Xenomai uses may not fire anymore. + Summarizing, the latencies incurred here are dependent upon CPU, BIOS, and motherboard; ie they're hard to predict, so we are conservative. Feel free to test on your platform, (xeno-test runs testsuite/latency diff --git a/scripts/Kconfig.frag b/scripts/Kconfig.frag index 3a52ed4..c136ebf 100644 --- a/scripts/Kconfig.frag +++ b/scripts/Kconfig.frag @@ -1,10 +1,11 @@ menu "Real-time sub-system" -comment "WARNING! You enabled APM, CPU Frequency scaling or ACPI 'processor'" - depends on APM || CPU_FREQ || ACPI_PROCESSOR -comment "option. These options are known to cause troubles with Xenomai." - depends on APM || CPU_FREQ || ACPI_PROCESSOR +if APM || CPU_FREQ || ACPI_PROCESSOR || INTEL_IDLE +comment "WARNING! You enabled APM, CPU Frequency scaling, ACPI 'processor'" +comment "or Intel cpuidle option. These options are known to cause troubles" +comment "with Xenomai, disable them." +endif comment "NOTE: Xenomai conflicts with PC speaker support." depends on !X86_TSC && X86 && INPUT_PCSPKR ___ Xenomai-git mailing list Xenomai-git@gna.org https://mail.gna.org/listinfo/xenomai-git
[Xenomai-git] Jan Kiszka : Add INTEL_IDLE to list of problematic config options
Module: xenomai-2.5 Branch: master Commit: 79bbd4d676320c36c7876e568cec90a0a485ee4d URL: http://git.xenomai.org/?p=xenomai-2.5.git;a=commit;h=79bbd4d676320c36c7876e568cec90a0a485ee4d Author: Jan Kiszka Date: Fri Jan 14 15:43:28 2011 +0100 Add INTEL_IDLE to list of problematic config options See TROUBLESHOOTING for explanation. Signed-off-by: Jan Kiszka --- TROUBLESHOOTING |4 scripts/Kconfig.frag |9 + 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/TROUBLESHOOTING b/TROUBLESHOOTING index 4d84a79..e8d4b53 100644 --- a/TROUBLESHOOTING +++ b/TROUBLESHOOTING @@ -57,6 +57,10 @@ sleep states, increasing latency in ways dependent upon both the BIOS's ACPI tables and code. You may be able to suppress the sleeping with 'idle=poll' boot-arg, test to find out +INTEL_IDLE: Just like ACPI_PROCESSOR, this idle driver sends the CPU +into deep C states, also causing huge latencies because the APIC timer +that Xenomai uses may not fire anymore. + Summarizing, the latencies incurred here are dependent upon CPU, BIOS, and motherboard; ie they're hard to predict, so we are conservative. Feel free to test on your platform, (xeno-test runs testsuite/latency diff --git a/scripts/Kconfig.frag b/scripts/Kconfig.frag index 3a52ed4..c136ebf 100644 --- a/scripts/Kconfig.frag +++ b/scripts/Kconfig.frag @@ -1,10 +1,11 @@ menu "Real-time sub-system" -comment "WARNING! You enabled APM, CPU Frequency scaling or ACPI 'processor'" - depends on APM || CPU_FREQ || ACPI_PROCESSOR -comment "option. These options are known to cause troubles with Xenomai." - depends on APM || CPU_FREQ || ACPI_PROCESSOR +if APM || CPU_FREQ || ACPI_PROCESSOR || INTEL_IDLE +comment "WARNING! You enabled APM, CPU Frequency scaling, ACPI 'processor'" +comment "or Intel cpuidle option. These options are known to cause troubles" +comment "with Xenomai, disable them." +endif comment "NOTE: Xenomai conflicts with PC speaker support." depends on !X86_TSC && X86 && INPUT_PCSPKR ___ Xenomai-git mailing list Xenomai-git@gna.org https://mail.gna.org/listinfo/xenomai-git