| Message ID | CAKohpokGrgFOtOT6Y3e4MOJBUQWT4FG4Mk-F6_M0V-pEEf3KYw@mail.gmail.com |
|---|---|
| State | Accepted |
| Headers | show |
On 06/05/2013 01:07 PM, Viresh Kumar wrote: > On 5 June 2013 10:12, Michael Wang <wangyun@linux.vnet.ibm.com> wrote: >> Hi, Viresh >> >> On 06/04/2013 07:20 PM, Viresh Kumar wrote: >> [snip] >>> diff --git a/kernel/sched/core.c b/kernel/sched/core.c >>> index 58453b8..638f6cb 100644 >>> --- a/kernel/sched/core.c >>> +++ b/kernel/sched/core.c >>> @@ -6533,16 +6533,13 @@ static int build_sched_domains(const struct cpumask *cpu_map, >>> sd = NULL; >>> for (tl = sched_domain_topology; tl->init; tl++) { >>> sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); >>> + if (!*per_cpu_ptr(d.sd, i)) >> >> What about: >> if (tl == sched_domain_topology) >> >> It cost less than per_cpu_ptr(), isn't it? > > How can I miss it.. Obviously its better :) > > See if below one looks better (Attached too in case gmail screws up > my mail).. Looks good to me :) Regards, Michael Wang > > --------x-------------x------------------ > > From: Viresh Kumar <viresh.kumar@linaro.org> > Date: Tue, 4 Jun 2013 15:41:15 +0530 > Subject: [PATCH] sched: Optimize build_sched_domains() for saving first SD > node for a cpu > > We are saving first scheduling domain for a cpu in build_sched_domains() by > iterating over the nested sd->child list. We don't actually need to do it this > way. > > tl will be equal to sched_domain_topology for the first iteration and so we can > set *per_cpu_ptr(d.sd, i) based on that. So, save pointer to first SD while > running the iteration loop over tl's. > > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > kernel/sched/core.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 58453b8..08a27be 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -6533,16 +6533,13 @@ static int build_sched_domains(const struct > cpumask *cpu_map, > sd = NULL; > for (tl = sched_domain_topology; tl->init; tl++) { > sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); > + if (tl == sched_domain_topology) > + *per_cpu_ptr(d.sd, i) = sd; > if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP)) > sd->flags |= SD_OVERLAP; > if (cpumask_equal(cpu_map, sched_domain_span(sd))) > break; > } > - > - while (sd->child) > - sd = sd->child; > - > - *per_cpu_ptr(d.sd, i) = sd; > } > > /* Build the groups for the domains */ >
On Wed, Jun 05, 2013 at 10:37:29AM +0530, Viresh Kumar wrote: > On 5 June 2013 10:12, Michael Wang <wangyun@linux.vnet.ibm.com> wrote: > > Hi, Viresh > > > > On 06/04/2013 07:20 PM, Viresh Kumar wrote: > > [snip] > >> diff --git a/kernel/sched/core.c b/kernel/sched/core.c > >> index 58453b8..638f6cb 100644 > >> --- a/kernel/sched/core.c > >> +++ b/kernel/sched/core.c > >> @@ -6533,16 +6533,13 @@ static int build_sched_domains(const struct cpumask *cpu_map, > >> sd = NULL; > >> for (tl = sched_domain_topology; tl->init; tl++) { > >> sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); > >> + if (!*per_cpu_ptr(d.sd, i)) > > > > What about: > > if (tl == sched_domain_topology) > > > > It cost less than per_cpu_ptr(), isn't it? > > How can I miss it.. Obviously its better :) > > See if below one looks better (Attached too in case gmail screws up > my mail).. > > --------x-------------x------------------ > > From: Viresh Kumar <viresh.kumar@linaro.org> > Date: Tue, 4 Jun 2013 15:41:15 +0530 > Subject: [PATCH] sched: Optimize build_sched_domains() for saving first SD > node for a cpu > > We are saving first scheduling domain for a cpu in build_sched_domains() by > iterating over the nested sd->child list. We don't actually need to do it this > way. > > tl will be equal to sched_domain_topology for the first iteration and so we can > set *per_cpu_ptr(d.sd, i) based on that. So, save pointer to first SD while > running the iteration loop over tl's. > > Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> > --- > kernel/sched/core.c | 7 ++----- > 1 file changed, 2 insertions(+), 5 deletions(-) > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 58453b8..08a27be 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -6533,16 +6533,13 @@ static int build_sched_domains(const struct > cpumask *cpu_map, Applying patch patches/viresh_kumar-_patch__sched-optimize_build_sched_domains_for_saving_first_sd.patch patching file kernel/sched/core.c patch: **** malformed patch at line 56: cpumask *cpu_map,
On 5 June 2013 16:34, Peter Zijlstra <peterz@infradead.org> wrote: > On Wed, Jun 05, 2013 at 10:37:29AM +0530, Viresh Kumar wrote: >> See if below one looks better (Attached too in case gmail screws up >> my mail).. > Applying patch > patches/viresh_kumar-_patch__sched-optimize_build_sched_domains_for_saving_first_sd.patch > patching file kernel/sched/core.c > patch: **** malformed patch at line 56: cpumask *cpu_map, You tried to apply patch from mail or attachment? I requested to pick attachment as gmail's copy-paste screws up patches. I rebased it over tip/master now: 2bf6874 Merge branch 'x86/cleanups' Patches are attached now.
On Wed, Jun 05, 2013 at 06:12:15PM +0530, Viresh Kumar wrote: > On 5 June 2013 16:34, Peter Zijlstra <peterz@infradead.org> wrote: > > On Wed, Jun 05, 2013 at 10:37:29AM +0530, Viresh Kumar wrote: > > >> See if below one looks better (Attached too in case gmail screws up > >> my mail).. > > > Applying patch > > patches/viresh_kumar-_patch__sched-optimize_build_sched_domains_for_saving_first_sd.patch > > patching file kernel/sched/core.c > > patch: **** malformed patch at line 56: cpumask *cpu_map, > > You tried to apply patch from mail or attachment? I requested to > pick attachment as gmail's copy-paste screws up patches. > From email; that's what my mailer is scripted for. TBH I didn't even notice the attachment. I'll go prod at the attachment.
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 58453b8..08a27be 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6533,16 +6533,13 @@ static int build_sched_domains(const struct cpumask *cpu_map, sd = NULL; for (tl = sched_domain_topology; tl->init; tl++) { sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); + if (tl == sched_domain_topology) + *per_cpu_ptr(d.sd, i) = sd; if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP)) sd->flags |= SD_OVERLAP; if (cpumask_equal(cpu_map, sched_domain_span(sd))) break; } - - while (sd->child) - sd = sd->child; - - *per_cpu_ptr(d.sd, i) = sd; }