| Message ID | 1349595838-31274-3-git-send-email-vincent.guittot@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Vincent, Few comments/questions. On Sunday 07 October 2012 01:13 PM, Vincent Guittot wrote: > This new flag SD SHARE_POWERLINE reflects the sharing of the power rail > between the members of a domain. As this is the current assumption of the > scheduler, the flag is added to all sched_domain > > Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> > --- > arch/ia64/include/asm/topology.h | 1 + > arch/tile/include/asm/topology.h | 1 + > include/linux/sched.h | 1 + > include/linux/topology.h | 3 +++ > kernel/sched/core.c | 5 +++++ > 5 files changed, 11 insertions(+) > > diff --git a/arch/ia64/include/asm/topology.h b/arch/ia64/include/asm/topology.h > index a2496e4..065c720 100644 > --- a/arch/ia64/include/asm/topology.h > +++ b/arch/ia64/include/asm/topology.h > @@ -65,6 +65,7 @@ void build_cpu_to_node_map(void); > | SD_BALANCE_EXEC \ > | SD_BALANCE_FORK \ > | SD_WAKE_AFFINE, \ > + | arch_sd_share_power_line() \ > .last_balance = jiffies, \ > .balance_interval = 1, \ > .nr_balance_failed = 0, \ > diff --git a/arch/tile/include/asm/topology.h b/arch/tile/include/asm/topology.h > index 7a7ce39..d39ed0b 100644 > --- a/arch/tile/include/asm/topology.h > +++ b/arch/tile/include/asm/topology.h > @@ -72,6 +72,7 @@ static inline const struct cpumask *cpumask_of_node(int node) > | 0*SD_PREFER_LOCAL \ > | 0*SD_SHARE_CPUPOWER \ > | 0*SD_SHARE_PKG_RESOURCES \ > + | arch_sd_share_power_line() \ > | 0*SD_SERIALIZE \ > , \ > .last_balance = jiffies, \ > diff --git a/include/linux/sched.h b/include/linux/sched.h > index 4786b20..74f2daf 100644 > --- a/include/linux/sched.h > +++ b/include/linux/sched.h > @@ -862,6 +862,7 @@ enum cpu_idle_type { > #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ > #define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks local to this domain */ > #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */ > +#define SD_SHARE_POWERLINE 0x0100 /* Domain members share power domain */ If you ignore the current use of SD_SHARE_CPUPOWER, isn't the meaning of CPUPOWER and POWERLINE is same here. Just trying to understand the clear meaning of this new flag. Have you not considered SD_SHARE_CPUPOWER because it is being used for cpu_power and needs at least minimum two domains ? SD_PACKING would have been probably more appropriate based on the way it is being used in further series. Regards Santosh
On 24 October 2012 17:17, Santosh Shilimkar <santosh.shilimkar@ti.com> wrote: > Vincent, > > Few comments/questions. > > > On Sunday 07 October 2012 01:13 PM, Vincent Guittot wrote: >> >> This new flag SD SHARE_POWERLINE reflects the sharing of the power rail >> between the members of a domain. As this is the current assumption of the >> scheduler, the flag is added to all sched_domain >> >> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> >> --- >> arch/ia64/include/asm/topology.h | 1 + >> arch/tile/include/asm/topology.h | 1 + >> include/linux/sched.h | 1 + >> include/linux/topology.h | 3 +++ >> kernel/sched/core.c | 5 +++++ >> 5 files changed, 11 insertions(+) >> >> diff --git a/arch/ia64/include/asm/topology.h >> b/arch/ia64/include/asm/topology.h >> index a2496e4..065c720 100644 >> --- a/arch/ia64/include/asm/topology.h >> +++ b/arch/ia64/include/asm/topology.h >> @@ -65,6 +65,7 @@ void build_cpu_to_node_map(void); >> | SD_BALANCE_EXEC \ >> | SD_BALANCE_FORK \ >> | SD_WAKE_AFFINE, \ >> + | arch_sd_share_power_line() \ >> .last_balance = jiffies, \ >> .balance_interval = 1, \ >> .nr_balance_failed = 0, \ >> diff --git a/arch/tile/include/asm/topology.h >> b/arch/tile/include/asm/topology.h >> index 7a7ce39..d39ed0b 100644 >> --- a/arch/tile/include/asm/topology.h >> +++ b/arch/tile/include/asm/topology.h >> @@ -72,6 +72,7 @@ static inline const struct cpumask *cpumask_of_node(int >> node) >> | 0*SD_PREFER_LOCAL \ >> | 0*SD_SHARE_CPUPOWER \ >> | 0*SD_SHARE_PKG_RESOURCES \ >> + | arch_sd_share_power_line() \ >> | 0*SD_SERIALIZE \ >> , \ >> .last_balance = jiffies, \ >> diff --git a/include/linux/sched.h b/include/linux/sched.h >> index 4786b20..74f2daf 100644 >> --- a/include/linux/sched.h >> +++ b/include/linux/sched.h >> @@ -862,6 +862,7 @@ enum cpu_idle_type { >> #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU >> */ >> #define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks >> local to this domain */ >> #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power >> */ >> +#define SD_SHARE_POWERLINE 0x0100 /* Domain members share power >> domain */ > > If you ignore the current use of SD_SHARE_CPUPOWER, isn't the meaning of > CPUPOWER and POWERLINE is same here. Just trying to understand the clear > meaning of this new flag. Have you not considered SD_SHARE_CPUPOWER > because it is being used for cpu_power and needs at least minimum two > domains ? SD_PACKING would have been probably more appropriate based > on the way it is being used in further series. CPUPOWER reflects the share of hw ressources between cores like for hyper threading. POWERLINE describes the fact that cores are sharing the same power line amore precisely the powergate. > > Regards > Santosh >
It looks like i need to describe more what On 29 October 2012 10:40, Vincent Guittot <vincent.guittot@linaro.org> wrote: > On 24 October 2012 17:17, Santosh Shilimkar <santosh.shilimkar@ti.com> wrote: >> Vincent, >> >> Few comments/questions. >> >> >> On Sunday 07 October 2012 01:13 PM, Vincent Guittot wrote: >>> >>> This new flag SD SHARE_POWERLINE reflects the sharing of the power rail >>> between the members of a domain. As this is the current assumption of the >>> scheduler, the flag is added to all sched_domain >>> >>> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> >>> --- >>> arch/ia64/include/asm/topology.h | 1 + >>> arch/tile/include/asm/topology.h | 1 + >>> include/linux/sched.h | 1 + >>> include/linux/topology.h | 3 +++ >>> kernel/sched/core.c | 5 +++++ >>> 5 files changed, 11 insertions(+) >>> >>> diff --git a/arch/ia64/include/asm/topology.h >>> b/arch/ia64/include/asm/topology.h >>> index a2496e4..065c720 100644 >>> --- a/arch/ia64/include/asm/topology.h >>> +++ b/arch/ia64/include/asm/topology.h >>> @@ -65,6 +65,7 @@ void build_cpu_to_node_map(void); >>> | SD_BALANCE_EXEC \ >>> | SD_BALANCE_FORK \ >>> | SD_WAKE_AFFINE, \ >>> + | arch_sd_share_power_line() \ >>> .last_balance = jiffies, \ >>> .balance_interval = 1, \ >>> .nr_balance_failed = 0, \ >>> diff --git a/arch/tile/include/asm/topology.h >>> b/arch/tile/include/asm/topology.h >>> index 7a7ce39..d39ed0b 100644 >>> --- a/arch/tile/include/asm/topology.h >>> +++ b/arch/tile/include/asm/topology.h >>> @@ -72,6 +72,7 @@ static inline const struct cpumask *cpumask_of_node(int >>> node) >>> | 0*SD_PREFER_LOCAL \ >>> | 0*SD_SHARE_CPUPOWER \ >>> | 0*SD_SHARE_PKG_RESOURCES \ >>> + | arch_sd_share_power_line() \ >>> | 0*SD_SERIALIZE \ >>> , \ >>> .last_balance = jiffies, \ >>> diff --git a/include/linux/sched.h b/include/linux/sched.h >>> index 4786b20..74f2daf 100644 >>> --- a/include/linux/sched.h >>> +++ b/include/linux/sched.h >>> @@ -862,6 +862,7 @@ enum cpu_idle_type { >>> #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU >>> */ >>> #define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks >>> local to this domain */ >>> #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power >>> */ >>> +#define SD_SHARE_POWERLINE 0x0100 /* Domain members share power >>> domain */ >> >> If you ignore the current use of SD_SHARE_CPUPOWER, isn't the meaning of >> CPUPOWER and POWERLINE is same here. Just trying to understand the clear >> meaning of this new flag. Have you not considered SD_SHARE_CPUPOWER >> because it is being used for cpu_power and needs at least minimum two >> domains ? SD_PACKING would have been probably more appropriate based >> on the way it is being used in further series. > > CPUPOWER reflects the share of hw ressources between cores like for > hyper threading. POWERLINE describes the fact that cores are sharing > the same power line amore precisely the powergate. Sorry, the mail has been sent too early while I was writing it CPUPOWER reflects the share of hw ressources between cores like for hyper threading. POWERLINE describes the fact that cores are sharing the same power line and more precisely the same power gating. It looks like I need to describe more precisely what i would mean with SHARE_POWERLINE. I don't want to use PACKING because it's more a behavior than a feature. If cores can power gate independently (!SD_SHARE_POWERLINE), packing small tasks is one interesting behavior but it may be not the only one. I want to make a difference between the HW configuration and the behavior we want to have above it Vincent >> >> Regards >> Santosh >>
On Monday 29 October 2012 03:20 PM, Vincent Guittot wrote: > It looks like i need to describe more what > > On 29 October 2012 10:40, Vincent Guittot <vincent.guittot@linaro.org> wrote: >> On 24 October 2012 17:17, Santosh Shilimkar <santosh.shilimkar@ti.com> wrote: >>> Vincent, >>> >>> Few comments/questions. >>> >>> >>> On Sunday 07 October 2012 01:13 PM, Vincent Guittot wrote: >>>> >>>> This new flag SD SHARE_POWERLINE reflects the sharing of the power rail >>>> between the members of a domain. As this is the current assumption of the >>>> scheduler, the flag is added to all sched_domain >>>> >>>> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> >>>> --- >>>> arch/ia64/include/asm/topology.h | 1 + >>>> arch/tile/include/asm/topology.h | 1 + >>>> include/linux/sched.h | 1 + >>>> include/linux/topology.h | 3 +++ >>>> kernel/sched/core.c | 5 +++++ >>>> 5 files changed, 11 insertions(+) >>>> >>>> diff --git a/arch/ia64/include/asm/topology.h >>>> b/arch/ia64/include/asm/topology.h >>>> index a2496e4..065c720 100644 >>>> --- a/arch/ia64/include/asm/topology.h >>>> +++ b/arch/ia64/include/asm/topology.h >>>> @@ -65,6 +65,7 @@ void build_cpu_to_node_map(void); >>>> | SD_BALANCE_EXEC \ >>>> | SD_BALANCE_FORK \ >>>> | SD_WAKE_AFFINE, \ >>>> + | arch_sd_share_power_line() \ >>>> .last_balance = jiffies, \ >>>> .balance_interval = 1, \ >>>> .nr_balance_failed = 0, \ >>>> diff --git a/arch/tile/include/asm/topology.h >>>> b/arch/tile/include/asm/topology.h >>>> index 7a7ce39..d39ed0b 100644 >>>> --- a/arch/tile/include/asm/topology.h >>>> +++ b/arch/tile/include/asm/topology.h >>>> @@ -72,6 +72,7 @@ static inline const struct cpumask *cpumask_of_node(int >>>> node) >>>> | 0*SD_PREFER_LOCAL \ >>>> | 0*SD_SHARE_CPUPOWER \ >>>> | 0*SD_SHARE_PKG_RESOURCES \ >>>> + | arch_sd_share_power_line() \ >>>> | 0*SD_SERIALIZE \ >>>> , \ >>>> .last_balance = jiffies, \ >>>> diff --git a/include/linux/sched.h b/include/linux/sched.h >>>> index 4786b20..74f2daf 100644 >>>> --- a/include/linux/sched.h >>>> +++ b/include/linux/sched.h >>>> @@ -862,6 +862,7 @@ enum cpu_idle_type { >>>> #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU >>>> */ >>>> #define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks >>>> local to this domain */ >>>> #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power >>>> */ >>>> +#define SD_SHARE_POWERLINE 0x0100 /* Domain members share power >>>> domain */ >>> >>> If you ignore the current use of SD_SHARE_CPUPOWER, isn't the meaning of >>> CPUPOWER and POWERLINE is same here. Just trying to understand the clear >>> meaning of this new flag. Have you not considered SD_SHARE_CPUPOWER >>> because it is being used for cpu_power and needs at least minimum two >>> domains ? SD_PACKING would have been probably more appropriate based >>> on the way it is being used in further series. >> >> CPUPOWER reflects the share of hw ressources between cores like for >> hyper threading. POWERLINE describes the fact that cores are sharing >> the same power line amore precisely the powergate. > > Sorry, the mail has been sent too early while I was writing it > > CPUPOWER reflects the share of hw ressources between cores like for > hyper threading. POWERLINE describes the fact that cores are sharing > the same power line and more precisely the same power gating. It looks > like I need to describe more precisely what i would mean with > SHARE_POWERLINE. > Yes. More description will help. I see bit of overlap POWERLINE flag with SD_SHARE_CPUPOWER and SD_SHARE_PKG_RESOURCES and hence the questions. > I don't want to use PACKING because it's more a behavior than a > feature. If cores can power gate independently (!SD_SHARE_POWERLINE), > packing small tasks is one interesting behavior but it may be not the > only one. I want to make a difference between the HW configuration and > the behavior we want to have above it > Fair enough. Thanks for clarification. Regards, Santosh
diff --git a/arch/ia64/include/asm/topology.h b/arch/ia64/include/asm/topology.h index a2496e4..065c720 100644 --- a/arch/ia64/include/asm/topology.h +++ b/arch/ia64/include/asm/topology.h @@ -65,6 +65,7 @@ void build_cpu_to_node_map(void); | SD_BALANCE_EXEC \ | SD_BALANCE_FORK \ | SD_WAKE_AFFINE, \ + | arch_sd_share_power_line() \ .last_balance = jiffies, \ .balance_interval = 1, \ .nr_balance_failed = 0, \ diff --git a/arch/tile/include/asm/topology.h b/arch/tile/include/asm/topology.h index 7a7ce39..d39ed0b 100644 --- a/arch/tile/include/asm/topology.h +++ b/arch/tile/include/asm/topology.h @@ -72,6 +72,7 @@ static inline const struct cpumask *cpumask_of_node(int node) | 0*SD_PREFER_LOCAL \ | 0*SD_SHARE_CPUPOWER \ | 0*SD_SHARE_PKG_RESOURCES \ + | arch_sd_share_power_line() \ | 0*SD_SERIALIZE \ , \ .last_balance = jiffies, \ diff --git a/include/linux/sched.h b/include/linux/sched.h index 4786b20..74f2daf 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -862,6 +862,7 @@ enum cpu_idle_type { #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ #define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks local to this domain */ #define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */ +#define SD_SHARE_POWERLINE 0x0100 /* Domain members share power domain */ #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */ diff --git a/include/linux/topology.h b/include/linux/topology.h index fec12d6..20964ab 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -99,6 +99,7 @@ int arch_update_cpu_topology(void); | 1*SD_WAKE_AFFINE \ | 1*SD_SHARE_CPUPOWER \ | 1*SD_SHARE_PKG_RESOURCES \ + | arch_sd_share_power_line() \ | 0*SD_SERIALIZE \ | 0*SD_PREFER_SIBLING \ | arch_sd_sibling_asym_packing() \ @@ -132,6 +133,7 @@ int arch_update_cpu_topology(void); | 0*SD_PREFER_LOCAL \ | 0*SD_SHARE_CPUPOWER \ | 1*SD_SHARE_PKG_RESOURCES \ + | arch_sd_share_power_line() \ | 0*SD_SERIALIZE \ , \ .last_balance = jiffies, \ @@ -163,6 +165,7 @@ int arch_update_cpu_topology(void); | 0*SD_PREFER_LOCAL \ | 0*SD_SHARE_CPUPOWER \ | 0*SD_SHARE_PKG_RESOURCES \ + | arch_sd_share_power_line() \ | 0*SD_SERIALIZE \ | 1*SD_PREFER_SIBLING \ , \ diff --git a/kernel/sched/core.c b/kernel/sched/core.c index d50fbac..dab7908 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6407,6 +6407,11 @@ int __weak arch_sd_sibling_asym_packing(void) return 0*SD_ASYM_PACKING; } +int __weak arch_sd_share_power_line(void) +{ + return 1*SD_SHARE_POWERLINE; +} + /* * Initializers for schedule domains * Non-inlined to reduce accumulated stack pressure in build_sched_domains()
This new flag SD SHARE_POWERLINE reflects the sharing of the power rail between the members of a domain. As this is the current assumption of the scheduler, the flag is added to all sched_domain Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> --- arch/ia64/include/asm/topology.h | 1 + arch/tile/include/asm/topology.h | 1 + include/linux/sched.h | 1 + include/linux/topology.h | 3 +++ kernel/sched/core.c | 5 +++++ 5 files changed, 11 insertions(+)