sched: Rework sched_domain topology definition

We replace the old way to configure the scheduler topology with a new method
which enables a platform to declare additionnal level (if needed).

We still have a default topology table definition that can be used by platform
that don't want more level than the SMT, MC, CPU and NUMA ones. This table can
be overwritten by an arch which either wants to add new level where a load
balance make sense like BOOK or powergating level or wants to change the flags
configuration of some levels.

For each level, we need a function pointer that returns cpumask for each cpu,
a function pointer that returns the flags for the level and a name. Only flags
that describe topology, can be set by an architecture. The current topology
flags are:

 SD_SHARE_CPUPOWER
 SD_SHARE_PKG_RESOURCES
 SD_NUMA
 SD_ASYM_PACKING

Then, each level must be a subset on the next one. The build sequence of the
sched_domain will take care of removing useless levels like those with 1 CPU
and those with the same CPU span and no more relevant information for
load balancing than its children.

Signed-off-by: Vincent Guittot <[email protected]>
Tested-by: Dietmar Eggemann <[email protected]>
Reviewed-by: Preeti U Murthy <[email protected]>
Reviewed-by: Dietmar Eggemann <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Hanjun Guo <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Jason Low <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
This commit is contained in:
Vincent Guittot 2014-04-11 11:44:37 +02:00 • committed by Ingo Molnar
commit 143e1e28cb
6 changed files with 186 additions and 287 deletions

View file

@ -44,39 +44,6 @@ static inline const struct cpumask *cpumask_of_node(int node)
/* For now, use numa node -1 for global allocation. */
#define pcibus_to_node(bus) ((void)(bus), -1)
/*
* TILE architecture has many cores integrated in one processor, so we need
* setup bigger balance_interval for both CPU/NODE scheduling domains to
* reduce process scheduling costs.
*/
/* sched_domains SD_CPU_INIT for TILE architecture */
#define SD_CPU_INIT (struct sched_domain) { \
.min_interval = 4, \
.max_interval = 128, \
.busy_factor = 64, \
.imbalance_pct = 125, \
.cache_nice_tries = 1, \
.busy_idx = 2, \
.idle_idx = 1, \
.newidle_idx = 0, \
.wake_idx = 0, \
.forkexec_idx = 0, \
\
.flags = 1*SD_LOAD_BALANCE \
| 1*SD_BALANCE_NEWIDLE \
| 1*SD_BALANCE_EXEC \
| 1*SD_BALANCE_FORK \
| 0*SD_BALANCE_WAKE \
| 0*SD_WAKE_AFFINE \
| 0*SD_SHARE_CPUPOWER \
| 0*SD_SHARE_PKG_RESOURCES \
| 0*SD_SERIALIZE \
, \
.last_balance = jiffies, \
.balance_interval = 32, \
}
/* By definition, we create nodes based on online memory. */
#define node_has_online_mem(nid) 1