linux/arch
Ricardo Neri 183b8ec38f x86/sched: Decrease further the priorities of SMT siblings
When scheduling, it is better to prefer a separate physical core rather
than the SMT sibling of a high priority core. The existing formula to
compute priorities takes such fact in consideration. There may exist,
however, combinations of priorities (i.e., maximum frequencies) in which
the priority of high-numbered SMT siblings of high-priority cores collides
with the priority of low-numbered SMT siblings of low-priority cores.

Consider for instance an SMT2 system with CPUs [0, 1] with priority 60 and
[2, 3] with priority 30(CPUs in brackets are SMT siblings. In such a case,
the resulting priorities would be [120, 60], [60, 30]. Thus, to ensure
that CPU2 has higher priority than CPU1, divide the raw priority by the
squared SMT iterator. The resulting priorities are [120, 30]. [60, 15].

Originally-by: Len Brown <len.brown@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210911011819.12184-2-ricardo.neri-calderon@linux.intel.com
2021-10-05 15:51:59 +02:00
..
alpha alpha: enable GENERIC_PCI_IOMAP unconditionally 2021-09-19 10:37:00 -07:00
arc Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
arm entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume() 2021-09-22 10:24:01 -04:00
arm64 x86: 2021-09-27 13:58:23 -07:00
csky entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume() 2021-09-22 10:24:01 -04:00
h8300 Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
hexagon Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
ia64 Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
m68k m68k: Remove set_fs() 2021-09-24 13:35:07 +02:00
microblaze Microblaze patches for 5.15-rc1 2021-09-08 16:02:13 -07:00
mips Networking fixes for 5.15-rc4, including fixes from mac80211, netfilter 2021-09-30 14:28:05 -07:00
nds32 nds32/setup: remove unused memblock_region variable in setup_memory() 2021-09-08 18:45:53 -07:00
nios2 NIOS2: setup.c: drop unused variable 'dram_start' 2021-09-27 08:34:54 -05:00
openrisc Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00
parisc parisc: Declare pci_iounmap() parisc version only when CONFIG_PCI enabled 2021-09-19 10:36:09 -07:00
powerpc entry: rseq: Call rseq_handle_notify_resume() in tracehook_notify_resume() 2021-09-22 10:24:01 -04:00
riscv Merge branch 'gcc-min-version-5.1' (make gcc-5.1 the minimum version) 2021-09-13 10:43:04 -07:00
s390 x86: 2021-09-27 13:58:23 -07:00
sh sh: pgtable-3level: fix cast to pointer from integer of different size 2021-09-24 16:13:35 -07:00
sparc sparc64: fix pci_iounmap() when CONFIG_PCI is not set 2021-09-20 10:56:32 -07:00
um This pull request contains the following changes for UML: 2021-09-09 13:45:26 -07:00
x86 x86/sched: Decrease further the priorities of SMT siblings 2021-10-05 15:51:59 +02:00
xtensa Tracing updates for 5.15: 2021-09-05 11:50:41 -07:00
.gitignore
Kconfig Merge branch 'akpm' (patches from Andrew) 2021-09-08 12:55:35 -07:00