Merge tag 'perf-core-2024-09-18' of git://git.kernel.org/pub/scm/linux/kernel/git...

Merge tag 'perf-core-2024-09-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf events updates from Ingo Molnar:

 - Implement per-PMU context rescheduling to significantly improve
   single-PMU performance, and related cleanups/fixes (Peter Zijlstra
   and Namhyung Kim)

 - Fix ancient bug resulting in a lot of events being dropped
   erroneously at higher sampling frequencies (Luo Gengkun)

 - uprobes enhancements:

     - Implement RCU-protected hot path optimizations for better
       performance:

         "For baseline vs SRCU, peak througput increased from 3.7 M/s
          (million uprobe triggerings per second) up to about 8 M/s. For
          uretprobes it's a bit more modest with bump from 2.4 M/s to
          5 M/s.

          For SRCU vs RCU Tasks Trace, peak throughput for uprobes
          increases further from 8 M/s to 10.3 M/s (+28%!), and for
          uretprobes from 5.3 M/s to 5.8 M/s (+11%), as we have more
          work to do on uretprobes side.

          Even single-thread (no contention) performance is slightly
          better: 3.276 M/s to 3.396 M/s (+3.5%) for uprobes, and 2.055
          M/s to 2.174 M/s (+5.8%) for uretprobes."

          (Andrii Nakryiko et al)

     - Document mmap_lock, don't abuse get_user_pages_remote() (Oleg
       Nesterov)

     - Cleanups & fixes to prepare for future work:
        - Remove uprobe_register_refctr()
	- Simplify error handling for alloc_uprobe()
        - Make uprobe_register() return struct uprobe *
        - Fold __uprobe_unregister() into uprobe_unregister()
        - Shift put_uprobe() from delete_uprobe() to uprobe_unregister()
        - BPF: Fix use-after-free in bpf_uprobe_multi_link_attach()
          (Oleg Nesterov)

 - New feature & ABI extension: allow events to use PERF_SAMPLE READ
   with inheritance, enabling sample based profiling of a group of
   counters over a hierarchy of processes or threads (Ben Gainey)

 - Intel uncore & power events updates:

      - Add Arrow Lake and Lunar Lake support
      - Add PERF_EV_CAP_READ_SCOPE
      - Clean up and enhance cpumask and hotplug support
        (Kan Liang)

      - Add LNL uncore iMC freerunning support
      - Use D0:F0 as a default device
        (Zhenyu Wang)

 - Intel PT: fix AUX snapshot handling race (Adrian Hunter)

 - Misc fixes and cleanups (James Clark, Jiri Olsa, Oleg Nesterov and
   Peter Zijlstra)

* tag 'perf-core-2024-09-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
  dmaengine: idxd: Clean up cpumask and hotplug for perfmon
  iommu/vt-d: Clean up cpumask and hotplug for perfmon
  perf/x86/intel/cstate: Clean up cpumask and hotplug
  perf: Add PERF_EV_CAP_READ_SCOPE
  perf: Generic hotplug support for a PMU with a scope
  uprobes: perform lockless SRCU-protected uprobes_tree lookup
  rbtree: provide rb_find_rcu() / rb_find_add_rcu()
  perf/uprobe: split uprobe_unregister()
  uprobes: travers uprobe's consumer list locklessly under SRCU protection
  uprobes: get rid of enum uprobe_filter_ctx in uprobe filter callbacks
  uprobes: protected uprobe lifetime with SRCU
  uprobes: revamp uprobe refcounting and lifetime management
  bpf: Fix use-after-free in bpf_uprobe_multi_link_attach()
  perf/core: Fix small negative period being ignored
  perf: Really fix event_function_call() locking
  perf: Optimize __pmu_ctx_sched_out()
  perf: Add context time freeze
  perf: Fix event_function_call() locking
  perf: Extract a few helpers
  perf: Optimize context reschedule for single PMU cases
  ...