[PATCH v0 0/5] perf: Introduce instruction trace filtering

From: Alexander Shishkin
Date: Fri Dec 11 2015 - 08:39:17 EST


Hi Peter,

Newer version of Intel PT supports address-based filtering, and this
patchset adds support for it to perf core and the PT pmu driver. It
works by configuring a number of address ranges in hardware and
telling it to use these ranges to filter its traces. Similar feature
also exists in ARM Coresight ETM/PTM and it is also taken into account
in this patchset.

Firstly, userspace configures filters via an ioctl(), filters are
formatted as an ascii string. Filters may refer to addresses in object
files for userspace code or kernel addresses. The latter might be
extended in the future to support kernel modules.

For userspace filters, we scan the task's vmas to see if any of them
match the defined filters (inode+offset) and if they do, calculate
memory offsets and program them into hardware. Note that since
different tasks will have different mappings for the same object
files, supporting cpu-wide events would require special tricks to
context-switch filters for userspace code.

Also, we monitor new mmap and exec events to update (or clear) filter
configuration.

This is based on my perf_mmap_close() patchset from yesterday [1], which
in turn is based on your perf/core queue.

[1] http://marc.info/?l=linux-kernel&m=144976438631073

Alexander Shishkin (5):
perf: Move set_filter() from behind EVENT_TRACING
perf: Extend perf_event_aux() to optionally iterate through more
events
perf: Introduce instruction trace filtering
perf/x86/intel/pt: IP filtering register/cpuid bits
perf/x86/intel/pt: Add support for instruction trace filtering in PT

arch/x86/include/asm/msr-index.h | 18 +
arch/x86/kernel/cpu/intel_pt.h | 32 +-
arch/x86/kernel/cpu/perf_event_intel_pt.c | 134 +++++-
include/linux/perf_event.h | 40 ++
kernel/events/core.c | 655 ++++++++++++++++++++++++++++--
5 files changed, 835 insertions(+), 44 deletions(-)

--
2.6.2

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