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3a6c51e4d6
The current rXXXX event specification creates event under PERF_TYPE_RAW
pmu type. This change allows to use rXXXX within pmu syntax, so it's
type is used via the following syntax:
-e 'cpu/r3c/'
-e 'cpum_cf/r0/'
The XXXX number goes directly to perf_event_attr::config the same way as
in '-e rXXXX' event. The perf_event_attr::type is filled with pmu type.
Committer testing:
So, lets see what goes in perf_event_attr::config for, say, the
'instructions' PERF_TYPE_HARDWARE (0) event, first we should look at how
to encode this event as a PERF_TYPE_RAW event for this specific CPU, an
AMD Ryzen 5:
# cat /sys/devices/cpu/events/instructions
event=0xc0
#
Then try with it _and_ the instruction, just to see that they are close
enough:
# perf stat -e rc0,instructions sleep 1
Performance counter stats for 'sleep 1':
919,794 rc0
919,898 instructions
1.000754579 seconds time elapsed
0.000715000 seconds user
0.000000000 seconds sys
#
Now we should try, before this patch, the PMU event encoding:
# perf stat -e cpu/rc0/ sleep 1
event syntax error: 'cpu/rc0/'
\___ unknown term
valid terms: event,edge,inv,umask,cmask,config,config1,config2,name,period,percore
#
Now with this patch, the three ways of specifying the 'instructions' CPU
counter are accepted:
# perf stat -e cpu/rc0/,rc0,instructions sleep 1
Performance counter stats for 'sleep 1':
892,948 cpu/rc0/
893,052 rc0
893,156 instructions
1.000931819 seconds time elapsed
0.000916000 seconds user
0.000000000 seconds sys
#
Requested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200416221405.437788-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
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In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
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the problems which may result by upgrading your kernel.