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Commitfdf1e29b61("perf expr: Add metric literals for topology.") fails on s390: # ./perf test -Fv 7 ... # FAILED tests/expr.c:173 #num_dies >= #num_packages ---- end ---- Simple expression parser: FAILED! # Investigating this issue leads to these functions: build_cpu_topology() +--> has_die_topology(void) { struct utsname uts; if (uname(&uts) < 0) return false; if (strncmp(uts.machine, "x86_64", 6)) return false; .... } which always returns false on s390. The caller build_cpu_topology() checks has_die_topology() return value. On false the the struct cpu_topology::die_cpu_list is not contructed and has zero entries. This leads to the failing comparison: #num_dies >= #num_packages. s390 of course has a positive number of packages. Fix this by adding s390 architecture to support CPU die list. Output after: # ./perf test -Fv 7 7: Simple expression parser : --- start --- division by zero syntax error ---- end ---- Simple expression parser: Ok # Fixes:fdf1e29b61("perf expr: Add metric literals for topology.") Reviewed-by: Ian Rogers <irogers@google.com> Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ian Rogers <irogers@google.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Link: https://lore.kernel.org/r/20211124090343.9436-1-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.