[PATCH v6 0/6] Optimize cgroup context switch

From: Ian Rogers
Date: Fri Feb 14 2020 - 02:51:45 EST


Avoid iterating over all per-CPU events during cgroup changing context
switches by organizing events by cgroup.

To make an efficient set of iterators, introduce a min max heap
utility with test.

The v6 patch reduces the patch set by 4 patches, it updates the cgroup
id and fixes part of the min_heap rename from v5.

The v5 patch set renames min_max_heap to min_heap as suggested by
Peter Zijlstra, it also addresses comments around preferring
__always_inline over inline.

The v4 patch set addresses review comments on the v3 patch set by
Peter Zijlstra.

These patches include a caching algorithm to improve the search for
the first event in a group by Kan Liang <kan.liang@xxxxxxxxxxxxxxx> as
well as rebasing hit "optimize event_filter_match during sched_in"
from https://lkml.org/lkml/2019/8/7/771.

The v2 patch set was modified by Peter Zijlstra in his perf/cgroup
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git

These patches follow Peter's reorganization and his fixes to the
perf_cpu_context min_heap storage code.

Ian Rogers (5):
lib: introduce generic min-heap
perf: Use min_heap in visit_groups_merge
perf: Add per perf_cpu_context min_heap storage
perf/cgroup: Grow per perf_cpu_context heap storage
perf/cgroup: Order events in RB tree by cgroup id

Peter Zijlstra (1):
perf/cgroup: Reorder perf_cgroup_connect()

include/linux/min_heap.h | 135 ++++++++++++++++++++
include/linux/perf_event.h | 7 ++
kernel/events/core.c | 251 +++++++++++++++++++++++++++++++------
lib/Kconfig.debug | 10 ++
lib/Makefile | 1 +
lib/test_min_heap.c | 194 ++++++++++++++++++++++++++++
6 files changed, 563 insertions(+), 35 deletions(-)
create mode 100644 include/linux/min_heap.h
create mode 100644 lib/test_min_heap.c

--
2.25.0.265.gbab2e86ba0-goog