| Message ID | 149821530581.5914.13068641070748575404.stgit@Solace (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 06/23/2017 11:55 AM, Dario Faggioli wrote: > With the aim of improving memory size and layout, and > at the same time trying to put related fields reside > in the same cacheline. > > Here's a summary of the output of `pahole`, with and > without this patch, for the affected data structures. > > csched_pcpu: > * Before: > size: 88, cachelines: 2, members: 6 > sum members: 80, holes: 1, sum holes: 4 > padding: 4 > paddings: 1, sum paddings: 5 > last cacheline: 24 bytes > * After: > size: 80, cachelines: 2, members: 6 > paddings: 1, sum paddings: 5 > last cacheline: 16 bytes > > csched_vcpu: > * Before: > size: 72, cachelines: 2, members: 9 > padding: 2 > last cacheline: 8 bytes > * After: > same numbers, but move some fields to put > related fields in same cache line. > > csched_private: > * Before: > size: 152, cachelines: 3, members: 17 > sum members: 140, holes: 2, sum holes: 8 > padding: 4 > paddings: 1, sum paddings: 5 > last cacheline: 24 bytes > * After: > same numbers, but move some fields to put > related fields in same cache line. > > Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com> Acked-by: George Dunlap <george.dunlap@citrix.com> > --- > Cc: George Dunlap <george.dunlap@citrix.com> > Cc: Anshul Makkar <anshulmakkar@gmail.com> > --- > xen/common/sched_credit.c | 41 ++++++++++++++++++++++++++--------------- > 1 file changed, 26 insertions(+), 15 deletions(-) > > diff --git a/xen/common/sched_credit.c b/xen/common/sched_credit.c > index efdf6bf..4f6330e 100644 > --- a/xen/common/sched_credit.c > +++ b/xen/common/sched_credit.c > @@ -169,10 +169,12 @@ integer_param("sched_credit_tslice_ms", sched_credit_tslice_ms); > struct csched_pcpu { > struct list_head runq; > uint32_t runq_sort_last; > - struct timer ticker; > - unsigned int tick; > + > unsigned int idle_bias; > unsigned int nr_runnable; > + > + unsigned int tick; > + struct timer ticker; > }; > > /* > @@ -181,13 +183,18 @@ struct csched_pcpu { > struct csched_vcpu { > struct list_head runq_elem; > struct list_head active_vcpu_elem; > + > + /* Up-pointers */ > struct csched_dom *sdom; > struct vcpu *vcpu; > - atomic_t credit; > - unsigned int residual; > + > s_time_t start_time; /* When we were scheduled (used for credit) */ > unsigned flags; > - int16_t pri; > + int pri; > + > + atomic_t credit; > + unsigned int residual; > + > #ifdef CSCHED_STATS > struct { > int credit_last; > @@ -219,21 +226,25 @@ struct csched_dom { > struct csched_private { > /* lock for the whole pluggable scheduler, nests inside cpupool_lock */ > spinlock_t lock; > - struct list_head active_sdom; > - uint32_t ncpus; > - struct timer master_ticker; > - unsigned int master; > + > cpumask_var_t idlers; > cpumask_var_t cpus; > + uint32_t *balance_bias; > + uint32_t runq_sort; > + unsigned int ratelimit_us; > + > + /* Period of master and tick in milliseconds */ > + unsigned int tslice_ms, tick_period_us, ticks_per_tslice; > + uint32_t ncpus; > + > + struct list_head active_sdom; > uint32_t weight; > uint32_t credit; > int credit_balance; > - uint32_t runq_sort; > - uint32_t *balance_bias; > - unsigned ratelimit_us; > - /* Period of master and tick in milliseconds */ > - unsigned tslice_ms, tick_period_us, ticks_per_tslice; > - unsigned credits_per_tslice; > + unsigned int credits_per_tslice; > + > + unsigned int master; > + struct timer master_ticker; > }; > > static void csched_tick(void *_cpu); >
diff --git a/xen/common/sched_credit.c b/xen/common/sched_credit.c index efdf6bf..4f6330e 100644 --- a/xen/common/sched_credit.c +++ b/xen/common/sched_credit.c @@ -169,10 +169,12 @@ integer_param("sched_credit_tslice_ms", sched_credit_tslice_ms); struct csched_pcpu { struct list_head runq; uint32_t runq_sort_last; - struct timer ticker; - unsigned int tick; + unsigned int idle_bias; unsigned int nr_runnable; + + unsigned int tick; + struct timer ticker; }; /* @@ -181,13 +183,18 @@ struct csched_pcpu { struct csched_vcpu { struct list_head runq_elem; struct list_head active_vcpu_elem; + + /* Up-pointers */ struct csched_dom *sdom; struct vcpu *vcpu; - atomic_t credit; - unsigned int residual; + s_time_t start_time; /* When we were scheduled (used for credit) */ unsigned flags; - int16_t pri; + int pri; + + atomic_t credit; + unsigned int residual; + #ifdef CSCHED_STATS struct { int credit_last; @@ -219,21 +226,25 @@ struct csched_dom { struct csched_private { /* lock for the whole pluggable scheduler, nests inside cpupool_lock */ spinlock_t lock; - struct list_head active_sdom; - uint32_t ncpus; - struct timer master_ticker; - unsigned int master; + cpumask_var_t idlers; cpumask_var_t cpus; + uint32_t *balance_bias; + uint32_t runq_sort; + unsigned int ratelimit_us; + + /* Period of master and tick in milliseconds */ + unsigned int tslice_ms, tick_period_us, ticks_per_tslice; + uint32_t ncpus; + + struct list_head active_sdom; uint32_t weight; uint32_t credit; int credit_balance; - uint32_t runq_sort; - uint32_t *balance_bias; - unsigned ratelimit_us; - /* Period of master and tick in milliseconds */ - unsigned tslice_ms, tick_period_us, ticks_per_tslice; - unsigned credits_per_tslice; + unsigned int credits_per_tslice; + + unsigned int master; + struct timer master_ticker; }; static void csched_tick(void *_cpu);
With the aim of improving memory size and layout, and at the same time trying to put related fields reside in the same cacheline. Here's a summary of the output of `pahole`, with and without this patch, for the affected data structures. csched_pcpu: * Before: size: 88, cachelines: 2, members: 6 sum members: 80, holes: 1, sum holes: 4 padding: 4 paddings: 1, sum paddings: 5 last cacheline: 24 bytes * After: size: 80, cachelines: 2, members: 6 paddings: 1, sum paddings: 5 last cacheline: 16 bytes csched_vcpu: * Before: size: 72, cachelines: 2, members: 9 padding: 2 last cacheline: 8 bytes * After: same numbers, but move some fields to put related fields in same cache line. csched_private: * Before: size: 152, cachelines: 3, members: 17 sum members: 140, holes: 2, sum holes: 8 padding: 4 paddings: 1, sum paddings: 5 last cacheline: 24 bytes * After: same numbers, but move some fields to put related fields in same cache line. Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com> --- Cc: George Dunlap <george.dunlap@citrix.com> Cc: Anshul Makkar <anshulmakkar@gmail.com> --- xen/common/sched_credit.c | 41 ++++++++++++++++++++++++++--------------- 1 file changed, 26 insertions(+), 15 deletions(-)