XP can provide events from two sources: watchpoints, observing traffic
on device ports and PMU looking at internal buses.
Unfortunately the sysfs definition of the PMU events was requiring
port number (instead of bus number) and direction (the buses are
unidirectional), as these fields were shared with the watchpoint event.
Although it does not introduce a major problem (port can be used as
bus alias and direction is simply ignored for XP PMU events), it's
better to fix it now, before external tools start depending on this
behaviour.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Since 688d4dfcdd "perf tools: Support
parsing parameterized events" the perf userspace tools understands
"argument=?" syntax in the events file, making sure that required
arguments are provided by the user and not defaulting to 0, causing
confusion.
This patch adds the required arguments lists for CCN events.
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
This patch adds a "cpumask" attribute to CCN's event_source class sysfs
directory. Perf user tool uses it to restrict events to the
processor(s) enumerated in this mask.
This patch provides a single CPU mask, making it possible to run "-a"
perf session (previously it would request the same CCN event, for
example cycle counter, on each available core and most likely fail).
Initially the mask is set to the CPU that happened to probe the driver,
but it will be changed when it is hot-un-plugged (active events are
migrated to another CPU then).
Example:
Performance counter stats for 'system wide':
CPU0 2968148 cycles
CPU1 2236736 cycles
CPU2 1797968 cycles
CPU3 1831715 cycles
CPU1 1201850868 ccn/cycles/
1.001241383 seconds time elapsed
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Driver providing perf backend for ARM Cache Coherent Network
interconnect. Supports counting all hardware events and crosspoint
watchpoints.
Currently works with CCN-504 only, although there should be
no changes required for CCN-508 (just impossible to test it now).
Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pawel Moll