b6d8b858db
perf test 17 'Setup struct perf_event_attr' fails on s390 z/VM guest,
using linux-next kernel.
Root cause is the fall-back from hardware counter cycles
perf_event_attr:
type 0 (PERF_TYPE_HARDWARE)
size 136
config 0 (PERF_COUNT_HW_CPU_CYCLES)
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|ADDR|PERIOD|DATA_SRC
read_format ID|LOST
which returns -ENOENT on s390 z/VM guest. This causes the code to fall
back to software counter task-clock, as can be seen in the debug output:
------------------------------------------------------------
perf_event_attr:
type 1 (PERF_TYPE_SOFTWARE)
size 136
config 0x1 (PERF_COUNT_SW_TASK_CLOCK) <-here
{ sample_period, sample_freq } 4000
sample_type IP|TID|TIME|ADDR|PERIOD|DATA_SRC
read_format ID|LOST
This succeeds on s390 z/VM guest.
This successful installation of the counter task-clock is not listed in
the expected results and the test case fails.
This is caused by commit
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| .. | ||
| base-record | ||
| base-record-spe | ||
| base-stat | ||
| README | ||
| system-wide-dummy | ||
| test-record-basic | ||
| test-record-branch-any | ||
| test-record-branch-filter-any | ||
| test-record-branch-filter-any_call | ||
| test-record-branch-filter-any_ret | ||
| test-record-branch-filter-hv | ||
| test-record-branch-filter-ind_call | ||
| test-record-branch-filter-k | ||
| test-record-branch-filter-u | ||
| test-record-C0 | ||
| test-record-count | ||
| test-record-data | ||
| test-record-dummy-C0 | ||
| test-record-freq | ||
| test-record-graph-default | ||
| test-record-graph-default-aarch64 | ||
| test-record-graph-dwarf | ||
| test-record-graph-fp | ||
| test-record-graph-fp-aarch64 | ||
| test-record-group-sampling | ||
| test-record-group1 | ||
| test-record-group2 | ||
| test-record-no-buffering | ||
| test-record-no-inherit | ||
| test-record-no-samples | ||
| test-record-period | ||
| test-record-pfm-period | ||
| test-record-raw | ||
| test-record-spe-period | ||
| test-record-spe-period-term | ||
| test-record-spe-physical-address | ||
| test-record-user-regs-no-sve-aarch64 | ||
| test-record-user-regs-old-sve-aarch64 | ||
| test-record-user-regs-sve-aarch64 | ||
| test-stat-basic | ||
| test-stat-C0 | ||
| test-stat-default | ||
| test-stat-detailed-1 | ||
| test-stat-detailed-2 | ||
| test-stat-detailed-3 | ||
| test-stat-group1 | ||
| test-stat-no-inherit | ||
The struct perf_event_attr test (attr tests) support
This testing support is embedded into perf directly and is governed by the PERF_TEST_ATTR environment variable and hook inside the sys_perf_event_open function.
The general idea is to store 'struct perf_event_attr' details for each event created within single perf command. Each event details are stored into separate text file. Once perf command is finished these files are checked for values we expect for command.
The attr tests consist of following parts:
tests/attr.c
This is the sys_perf_event_open hook implementation. The hook is triggered when the PERF_TEST_ATTR environment variable is defined. It must contain name of existing directory with access and write permissions.
For each sys_perf_event_open call event details are stored in separate file. Besides 'struct perf_event_attr' values we also store 'fd' and 'group_fd' values to allow checking for groups.
tests/attr.py
This is the python script that does all the hard work. It reads the test definition, executes it and checks results.
tests/attr/
Directory containing all attr test definitions. Following tests are defined (with perf commands):
perf record kill (test-record-basic) perf record -b kill (test-record-branch-any) perf record -j any kill (test-record-branch-filter-any) perf record -j any_call kill (test-record-branch-filter-any_call) perf record -j any_ret kill (test-record-branch-filter-any_ret) perf record -j hv kill (test-record-branch-filter-hv) perf record -j ind_call kill (test-record-branch-filter-ind_call) perf record -j k kill (test-record-branch-filter-k) perf record -j u kill (test-record-branch-filter-u) perf record -c 123 kill (test-record-count) perf record -d kill (test-record-data) perf record -F 100 kill (test-record-freq) perf record -g kill (test-record-graph-default) perf record -g kill (test-record-graph-default-aarch64) perf record --call-graph dwarf kill (test-record-graph-dwarf) perf record --call-graph fp kill (test-record-graph-fp) perf record --call-graph fp kill (test-record-graph-fp-aarch64) perf record -e '{cycles,instructions}' kill (test-record-group1) perf record -e '{cycles/period=1/,instructions/period=2/}:S' kill (test-record-group2) perf record -D kill (test-record-no-delay) perf record -i kill (test-record-no-inherit) perf record -n kill (test-record-no-samples) perf record -c 100 -P kill (test-record-period) perf record -c 1 --pfm-events=cycles:period=2 (test-record-pfm-period) perf record -R kill (test-record-raw) perf record -c 2 -e arm_spe_0// -- kill (test-record-spe-period) perf record -e arm_spe_0/period=3/ -- kill (test-record-spe-period-term) perf record -e arm_spe_0/pa_enable=1/ -- kill (test-record-spe-physical-address) perf stat -e cycles kill (test-stat-basic) perf stat kill (test-stat-default) perf stat -d kill (test-stat-detailed-1) perf stat -dd kill (test-stat-detailed-2) perf stat -ddd kill (test-stat-detailed-3) perf stat -e '{cycles,instructions}' kill (test-stat-group1) perf stat -i -e cycles kill (test-stat-no-inherit)