| Message ID | 1417772453-22483-1-git-send-email-ethan.zhao@oracle.com (mailing list archive) |
|---|---|
| State | RFC, archived |
| Headers | show |
On 12/5/2014 4:40 AM, Ethan Zhao wrote: > To force loading on Oracle Sun X86 servers, provide one kernel command line > parameter > > intel_pstate = force > > For those who be aware of the risk of no power capping capabily working and > try to get better performance with this driver. > > Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> > Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com> > --- > v2: change to hardware vendor specific naming parameter. > v4: refine code and doc. > v5&v6: fix a typo in doc. > v7: change enum PCC to PPC. > v8: change the name of kernel command line parameter to generic one. > > Documentation/kernel-parameters.txt | 5 +++++ > drivers/cpufreq/intel_pstate.c | 6 +++++- > 2 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 479f332..7d0983e 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -1446,6 +1446,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > disable > Do not enable intel_pstate as the default > scaling driver for the supported processors > + force > + Enable intel_pstate on systems where it may cause problems to > + happen due to conflicts with platform firmware attempting to > + drive P-states by itself in certain situations (for thermal > + control or power capping in general or other purposes). I suggest something like: Enable intel_pstate on systems that prohibit it by default in favor of acpi-cpufreq. Forcing the intel_pstate driver instead of acpi-cpufreq may disable platform features, such as thermal controls and power capping, that rely on ACPI p-state information being used by the OS and therefore should be used with care. This option does not work with processors that aren't supported by the intel_pstate driver or on platforms that use pcc-cpufreq instead of acpi-cpufreq. Maybe this is too specific but I believe it is accurate. Comments? -- ljk > > intremap= [X86-64, Intel-IOMMU] > on enable Interrupt Remapping (default) > diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c > index 1bb62ca..2654e13 100644 > --- a/drivers/cpufreq/intel_pstate.c > +++ b/drivers/cpufreq/intel_pstate.c > @@ -866,6 +866,7 @@ static struct cpufreq_driver intel_pstate_driver = { > }; > > static int __initdata no_load; > +static unsigned int force_load; > > static int intel_pstate_msrs_not_valid(void) > { > @@ -1003,7 +1004,8 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) > case PSS: > return intel_pstate_no_acpi_pss(); > case PPC: > - return intel_pstate_has_acpi_ppc(); > + return intel_pstate_has_acpi_ppc() && > + (!force_load); > } > } > > @@ -1078,6 +1080,8 @@ static int __init intel_pstate_setup(char *str) > > if (!strcmp(str, "disable")) > no_load = 1; > + if (!strcmp(str, "force")) > + force_load = 1; > return 0; > } > early_param("intel_pstate", intel_pstate_setup); > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Friday, December 05, 2014 11:09:29 AM Linda Knippers wrote: > On 12/5/2014 4:40 AM, Ethan Zhao wrote: > > To force loading on Oracle Sun X86 servers, provide one kernel command line > > parameter > > > > intel_pstate = force > > > > For those who be aware of the risk of no power capping capabily working and > > try to get better performance with this driver. > > > > Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> > > Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com> > > --- > > v2: change to hardware vendor specific naming parameter. > > v4: refine code and doc. > > v5&v6: fix a typo in doc. > > v7: change enum PCC to PPC. > > v8: change the name of kernel command line parameter to generic one. > > > > Documentation/kernel-parameters.txt | 5 +++++ > > drivers/cpufreq/intel_pstate.c | 6 +++++- > > 2 files changed, 10 insertions(+), 1 deletion(-) > > > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > > index 479f332..7d0983e 100644 > > --- a/Documentation/kernel-parameters.txt > > +++ b/Documentation/kernel-parameters.txt > > @@ -1446,6 +1446,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > > disable > > Do not enable intel_pstate as the default > > scaling driver for the supported processors > > + force > > + Enable intel_pstate on systems where it may cause problems to > > + happen due to conflicts with platform firmware attempting to > > + drive P-states by itself in certain situations (for thermal > > + control or power capping in general or other purposes). > > I suggest something like: > Enable intel_pstate on systems that prohibit it by > default in favor of acpi-cpufreq. Forcing the > intel_pstate driver instead of acpi-cpufreq may disable > platform features, such as thermal controls and power > capping, that rely on ACPI p-state information being > used by the OS and therefore should be used with care. > This option does not work with processors that aren't > supported by the intel_pstate driver or on platforms > that use pcc-cpufreq instead of acpi-cpufreq. > > Maybe this is too specific but I believe it is accurate. Comments? Looks good to me, thanks!
Linda? > ? 2014?12?6??00:09?Linda Knippers <linda.knippers@hp.com> ??? > >> On 12/5/2014 4:40 AM, Ethan Zhao wrote: >> To force loading on Oracle Sun X86 servers, provide one kernel command line >> parameter >> >> intel_pstate = force >> >> For those who be aware of the risk of no power capping capabily working and >> try to get better performance with this driver. >> >> Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> >> Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com> >> --- >> v2: change to hardware vendor specific naming parameter. >> v4: refine code and doc. >> v5&v6: fix a typo in doc. >> v7: change enum PCC to PPC. >> v8: change the name of kernel command line parameter to generic one. >> >> Documentation/kernel-parameters.txt | 5 +++++ >> drivers/cpufreq/intel_pstate.c | 6 +++++- >> 2 files changed, 10 insertions(+), 1 deletion(-) >> >> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt >> index 479f332..7d0983e 100644 >> --- a/Documentation/kernel-parameters.txt >> +++ b/Documentation/kernel-parameters.txt >> @@ -1446,6 +1446,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. >> disable >> Do not enable intel_pstate as the default >> scaling driver for the supported processors >> + force >> + Enable intel_pstate on systems where it may cause problems to >> + happen due to conflicts with platform firmware attempting to >> + drive P-states by itself in certain situations (for thermal >> + control or power capping in general or other purposes). > > I suggest something like: > Enable intel_pstate on systems that prohibit it by > default in favor of acpi-cpufreq. Forcing the > intel_pstate driver instead of acpi-cpufreq may disable > platform features, such as thermal controls and power > capping, that rely on ACPI p-state information being P-States > Used by the OS and therefore should be used with care. Indicated to OSPM caution > This option does not work with processors that aren't > supported by the intel_pstate driver or on platforms > that use pcc-cpufreq instead of acpi-cpufreq. > > Maybe this is too specific but I believe it is accurate. Comments? > Looks better to me, except some words commented. Thanks, Ethan > -- ljk > >> >> intremap= [X86-64, Intel-IOMMU] >> on enable Interrupt Remapping (default) >> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c >> index 1bb62ca..2654e13 100644 >> --- a/drivers/cpufreq/intel_pstate.c >> +++ b/drivers/cpufreq/intel_pstate.c >> @@ -866,6 +866,7 @@ static struct cpufreq_driver intel_pstate_driver = { >> }; >> >> static int __initdata no_load; >> +static unsigned int force_load; >> >> static int intel_pstate_msrs_not_valid(void) >> { >> @@ -1003,7 +1004,8 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) >> case PSS: >> return intel_pstate_no_acpi_pss(); >> case PPC: >> - return intel_pstate_has_acpi_ppc(); >> + return intel_pstate_has_acpi_ppc() && >> + (!force_load); >> } >> } >> >> @@ -1078,6 +1080,8 @@ static int __init intel_pstate_setup(char *str) >> >> if (!strcmp(str, "disable")) >> no_load = 1; >> + if (!strcmp(str, "force")) >> + force_load = 1; >> return 0; >> } >> early_param("intel_pstate", intel_pstate_setup); > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 12/5/2014 9:16 PM, ethan wrote: > Linda? > >> ? 2014?12?6??00:09?Linda Knippers <linda.knippers@hp.com> ??? >> >>> On 12/5/2014 4:40 AM, Ethan Zhao wrote: >>> To force loading on Oracle Sun X86 servers, provide one kernel command line >>> parameter >>> >>> intel_pstate = force >>> >>> For those who be aware of the risk of no power capping capabily working and >>> try to get better performance with this driver. >>> >>> Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com> >>> Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com> >>> --- >>> v2: change to hardware vendor specific naming parameter. >>> v4: refine code and doc. >>> v5&v6: fix a typo in doc. >>> v7: change enum PCC to PPC. >>> v8: change the name of kernel command line parameter to generic one. >>> >>> Documentation/kernel-parameters.txt | 5 +++++ >>> drivers/cpufreq/intel_pstate.c | 6 +++++- >>> 2 files changed, 10 insertions(+), 1 deletion(-) >>> >>> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt >>> index 479f332..7d0983e 100644 >>> --- a/Documentation/kernel-parameters.txt >>> +++ b/Documentation/kernel-parameters.txt >>> @@ -1446,6 +1446,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. >>> disable >>> Do not enable intel_pstate as the default >>> scaling driver for the supported processors >>> + force >>> + Enable intel_pstate on systems where it may cause problems to >>> + happen due to conflicts with platform firmware attempting to >>> + drive P-states by itself in certain situations (for thermal >>> + control or power capping in general or other purposes). >> >> I suggest something like: >> Enable intel_pstate on systems that prohibit it by >> default in favor of acpi-cpufreq. Forcing the >> intel_pstate driver instead of acpi-cpufreq may disable >> platform features, such as thermal controls and power >> capping, that rely on ACPI p-state information being > P-States >> Used by the OS and therefore should be used with care. > Indicated to OSPM caution >> This option does not work with processors that aren't >> supported by the intel_pstate driver or on platforms >> that use pcc-cpufreq instead of acpi-cpufreq. >> >> Maybe this is too specific but I believe it is accurate. Comments? >> > > Looks better to me, except some words commented. Your suggestions look fine to me. -- ljk > > Thanks, > Ethan >> -- ljk >> >>> >>> intremap= [X86-64, Intel-IOMMU] >>> on enable Interrupt Remapping (default) >>> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c >>> index 1bb62ca..2654e13 100644 >>> --- a/drivers/cpufreq/intel_pstate.c >>> +++ b/drivers/cpufreq/intel_pstate.c >>> @@ -866,6 +866,7 @@ static struct cpufreq_driver intel_pstate_driver = { >>> }; >>> >>> static int __initdata no_load; >>> +static unsigned int force_load; >>> >>> static int intel_pstate_msrs_not_valid(void) >>> { >>> @@ -1003,7 +1004,8 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) >>> case PSS: >>> return intel_pstate_no_acpi_pss(); >>> case PPC: >>> - return intel_pstate_has_acpi_ppc(); >>> + return intel_pstate_has_acpi_ppc() && >>> + (!force_load); >>> } >>> } >>> >>> @@ -1078,6 +1080,8 @@ static int __init intel_pstate_setup(char *str) >>> >>> if (!strcmp(str, "disable")) >>> no_load = 1; >>> + if (!strcmp(str, "force")) >>> + force_load = 1; >>> return 0; >>> } >>> early_param("intel_pstate", intel_pstate_setup); >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-pm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 479f332..7d0983e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1446,6 +1446,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. disable Do not enable intel_pstate as the default scaling driver for the supported processors + force + Enable intel_pstate on systems where it may cause problems to + happen due to conflicts with platform firmware attempting to + drive P-states by itself in certain situations (for thermal + control or power capping in general or other purposes). intremap= [X86-64, Intel-IOMMU] on enable Interrupt Remapping (default) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 1bb62ca..2654e13 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -866,6 +866,7 @@ static struct cpufreq_driver intel_pstate_driver = { }; static int __initdata no_load; +static unsigned int force_load; static int intel_pstate_msrs_not_valid(void) { @@ -1003,7 +1004,8 @@ static bool intel_pstate_platform_pwr_mgmt_exists(void) case PSS: return intel_pstate_no_acpi_pss(); case PPC: - return intel_pstate_has_acpi_ppc(); + return intel_pstate_has_acpi_ppc() && + (!force_load); } } @@ -1078,6 +1080,8 @@ static int __init intel_pstate_setup(char *str) if (!strcmp(str, "disable")) no_load = 1; + if (!strcmp(str, "force")) + force_load = 1; return 0; } early_param("intel_pstate", intel_pstate_setup);