linux/arch/x86/events
Alexander Shishkin 39152ee51b perf/x86/intel/pt: Get rid of reverse lookup table for ToPA
In order to quickly find a ToPA entry by its page offset in the buffer,
we're using a reverse lookup table. The problem with it is that it's a
large array of mostly similar pointers, especially so now that we're
using high order allocations from the page allocator. Because its size
is limited to whatever is the maximum for kmalloc(), it places a limit
on the number of ToPA entries per buffer, and therefore, on the total
buffer size, which otherwise doesn't have to be there.

Replace the reverse lookup table with a simple runtime lookup. With the
high order AUX allocations in place, the runtime penalty of such a lookup
is much smaller and in cases where all entries in a ToPA table are of
the same size, the complexity is O(1).

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20190821124727.73310-7-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-08-26 12:00:16 +02:00
..
amd perf/x86/amd/uncore: Set the thread mask for F17h L3 PMCs 2019-07-13 11:21:27 +02:00
intel perf/x86/intel/pt: Get rid of reverse lookup table for ToPA 2019-08-26 12:00:16 +02:00
core.c perf/x86: Fix typo in comment 2019-08-19 11:50:24 +02:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile perf/x86: Add MSR probe interface 2019-06-24 19:28:31 +02:00
msr.c perf/x86/msr: Use new probe function 2019-06-24 19:28:32 +02:00
perf_event.h Linux 5.2 2019-07-08 18:04:41 +02:00
probe.c perf/x86: Add MSR probe interface 2019-06-24 19:28:31 +02:00
probe.h perf/x86: Add MSR probe interface 2019-06-24 19:28:31 +02:00