fb5962f81e
On linux-next tree 'perf test 95' ("Check branch stack sampling") was
added recently.
s390 does not support branch sampling at all and the test case fails
despite for checking branch support before hand.
The check for support of branching uses the software event named "dummy",
as seen in the line:
perf record -b -o- -e dummy -B true > /dev/null 2>&1 || exit 2
However when the branch recording is actually done, a different event is
used, as seen in the line:
perf record -o $TMPDIR/... --branch-filter any,save_type,u -- ...
The event is omitted and for "perf record" the default event is cycles,
which is not supported by s390 and this fails when executed on s390:
# perf record --branch-filter any,save_type,u -- /tmp/__perf_test.program.iDSmQ/a.out
Error:
cycles: PMU Hardware or event type doesn't support branch stack sampling.
#
Therefore fix this and use the same event cycles for testing support
and actually running the test.
Output before:
# ./perf test -Fv 95
95: Check branch stack sampling :
--- start ---
Testing user branch stack sampling
---- end ----
Check branch stack sampling: FAILED!
#
Output after:
# ./perf test -Fv 95
95: Check branch stack sampling :
--- start ---
---- end ----
Check branch stack sampling: Skip
#
Fixes:
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: 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 requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.