463538a383
Commit 5aa98879efe7 ("s390/cpum_sf: prohibit callchain data collection")
prohibits call graph sampling for hardware events on s390. The
information recorded is out of context and does not match.
On s390 this commit now breaks test case 68 Zstd perf.data
compression/decompression.
Therefore omit call graph sampling on s390 in this test.
Output before:
[root@t35lp46 perf]# ./perf test -Fv 68
68: Zstd perf.data compression/decompression :
--- start ---
Collecting compressed record file:
Error:
cycles: PMU Hardware doesn't support sampling/overflow-interrupts.
Try 'perf stat'
---- end ----
Zstd perf.data compression/decompression: FAILED!
[root@t35lp46 perf]#
Output after:
[root@t35lp46 perf]# ./perf test -Fv 68
68: Zstd perf.data compression/decompression :
--- start ---
Collecting compressed record file:
500+0 records in
500+0 records out
256000 bytes (256 kB, 250 KiB) copied, 0.00615638 s, 41.6 MB/s
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.004 MB /tmp/perf.data.X3M,
compressed (original 0.002 MB, ratio is 3.609) ]
Checking compressed events stats:
# compressed : Zstd, level = 1, ratio = 4
COMPRESSED events: 1
2ELIFREPh---- end ----
Zstd perf.data compression/decompression: Ok
[root@t35lp46 perf]#
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200729135314.91281-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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.