Revision 7178fb0b239d1c037876301c116fc9a6c1bd2ac0 authored by Linus Torvalds on 05 May 2019, 21:37:25 UTC, committed by Linus Torvalds on 05 May 2019, 21:37:25 UTC
Pull perf fixes from Ingo Molnar:
 "I'd like to apologize for this very late pull request: I was dithering
  through the week whether to send the fixes, and then yesterday Jiri's
  crash fix for a regression introduced in this cycle clearly marked
  perf/urgent as 'must merge now'.

  Most of the commits are tooling fixes, plus there's three kernel fixes
  via four commits:

    - race fix in the Intel PEBS code

    - fix an AUX bug and roll back a previous attempt

    - fix AMD family 17h generic HW cache-event perf counters

  The largest diffstat contribution comes from the AMD fix - a new event
  table is introduced, which is a fairly low risk change but has a large
  linecount"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Fix race in intel_pmu_disable_event()
  perf/x86/intel/pt: Remove software double buffering PMU capability
  perf/ring_buffer: Fix AUX software double buffering
  perf tools: Remove needless asm/unistd.h include fixing build in some places
  tools arch uapi: Copy missing unistd.h headers for arc, hexagon and riscv
  tools build: Add -ldl to the disassembler-four-args feature test
  perf cs-etm: Always allocate memory for cs_etm_queue::prev_packet
  perf cs-etm: Don't check cs_etm_queue::prev_packet validity
  perf report: Report OOM in status line in the GTK UI
  perf bench numa: Add define for RUSAGE_THREAD if not present
  tools lib traceevent: Change tag string for error
  perf annotate: Fix build on 32 bit for BPF annotation
  tools uapi x86: Sync vmx.h with the kernel
  perf bpf: Return value with unlocking in perf_env__find_btf()
  MAINTAINERS: Include vendor specific files under arch/*/events/*
  perf/x86/amd: Update generic hardware cache events for Family 17h
2 parent s 70c9fb5 + 6f55967
Raw File
Kconfig.preempt

choice
	prompt "Preemption Model"
	default PREEMPT_NONE

config PREEMPT_NONE
	bool "No Forced Preemption (Server)"
	help
	  This is the traditional Linux preemption model, geared towards
	  throughput. It will still provide good latencies most of the
	  time, but there are no guarantees and occasional longer delays
	  are possible.

	  Select this option if you are building a kernel for a server or
	  scientific/computation system, or if you want to maximize the
	  raw processing power of the kernel, irrespective of scheduling
	  latencies.

config PREEMPT_VOLUNTARY
	bool "Voluntary Kernel Preemption (Desktop)"
	depends on !ARCH_NO_PREEMPT
	help
	  This option reduces the latency of the kernel by adding more
	  "explicit preemption points" to the kernel code. These new
	  preemption points have been selected to reduce the maximum
	  latency of rescheduling, providing faster application reactions,
	  at the cost of slightly lower throughput.

	  This allows reaction to interactive events by allowing a
	  low priority process to voluntarily preempt itself even if it
	  is in kernel mode executing a system call. This allows
	  applications to run more 'smoothly' even when the system is
	  under load.

	  Select this if you are building a kernel for a desktop system.

config PREEMPT
	bool "Preemptible Kernel (Low-Latency Desktop)"
	depends on !ARCH_NO_PREEMPT
	select PREEMPT_COUNT
	select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK
	help
	  This option reduces the latency of the kernel by making
	  all kernel code (that is not executing in a critical section)
	  preemptible.  This allows reaction to interactive events by
	  permitting a low priority process to be preempted involuntarily
	  even if it is in kernel mode executing a system call and would
	  otherwise not be about to reach a natural preemption point.
	  This allows applications to run more 'smoothly' even when the
	  system is under load, at the cost of slightly lower throughput
	  and a slight runtime overhead to kernel code.

	  Select this if you are building a kernel for a desktop or
	  embedded system with latency requirements in the milliseconds
	  range.

endchoice

config PREEMPT_COUNT
       bool
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