From 1c6a800cde3b818fd8320b5d402f2d77d2948c00 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 29 Apr 2010 18:58:32 -0300 Subject: perf test: Initial regression testing command MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit First an example with the first internal test: [acme@doppio linux-2.6-tip]$ perf test 1: vmlinux symtab matches kallsyms: Ok So it run just one test, that is "vmlinux symtab matches kallsyms", and it was successful. If we run it in verbose mode, we'll see details about errors and extra warnings for non-fatal problems: [acme@doppio linux-2.6-tip]$ perf test -v 1: vmlinux symtab matches kallsyms: --- start --- Looking at the vmlinux_path (5 entries long) No build_id in vmlinux, ignoring it No build_id in /boot/vmlinux, ignoring it No build_id in /boot/vmlinux-2.6.34-rc4-tip+, ignoring it Using /lib/modules/2.6.34-rc4-tip+/build/vmlinux for symbols Maps only in vmlinux: ffffffff81cb81b1-ffffffff81e1149b 0 [kernel].init.text ffffffff81e1149c-ffffffff9fffffff 0 [kernel].exit.text ffffffffff600000-ffffffffff6000ff 0 [kernel].vsyscall_0 ffffffffff600100-ffffffffff6003ff 0 [kernel].vsyscall_fn ffffffffff600400-ffffffffff6007ff 0 [kernel].vsyscall_1 ffffffffff600800-ffffffffffffffff 0 [kernel].vsyscall_2 Maps in vmlinux with a different name in kallsyms: ffffffffff600000-ffffffffff6000ff 0 [kernel].vsyscall_0 in kallsyms as [kernel].0 ffffffffff600100-ffffffffff6003ff 0 [kernel].vsyscall_fn in kallsyms as: *ffffffffff600100-ffffffffff60012f 0 [kernel].2 ffffffffff600400-ffffffffff6007ff 0 [kernel].vsyscall_1 in kallsyms as [kernel].6 ffffffffff600800-ffffffffffffffff 0 [kernel].vsyscall_2 in kallsyms as [kernel].8 Maps only in kallsyms: ffffffffff600130-ffffffffff6003ff 0 [kernel].4 ---- end ---- vmlinux symtab matches kallsyms: Ok [acme@doppio linux-2.6-tip]$ In the above case we only know the name of the non contiguous kernel ranges in the address space when reading the symbol information from the ELF symtab in vmlinux. The /proc/kallsyms file lack this, we only notice they are separate because there are modules after the kernel and after that more kernel functions, so we need to have a module rbtree backed by the module .ko path to get symtabs in the vmlinux case. The tool uses it to match by address to emit appropriate warning, but don't considers this fatal. The .init.text and .exit.text ines, of course, aren't in kallsyms, so I left these cases just as extra info in verbose mode. The end of the sections also aren't in kallsyms, so we the symbols layer does another pass and sets the end addresses as the next map start minus one, which sometimes pads, causing harmless mismatches. But at least the symbols match, tested it by copying /proc/kallsyms to /tmp/kallsyms and doing changes to see if they were detected. This first test also should serve as a first stab at documenting the symbol library by providing a self contained example that exercises it together with comments about what is being done. More tests to check if actions done on a monitored app, like doing mmaps, etc, makes the kernel generate the expected events should be added next. Cc: Frédéric Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra LKML-Reference: Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/command-list.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/perf/command-list.txt') diff --git a/tools/perf/command-list.txt b/tools/perf/command-list.txt index 2a1162d413a8..80a1a446ce35 100644 --- a/tools/perf/command-list.txt +++ b/tools/perf/command-list.txt @@ -20,3 +20,4 @@ perf-probe mainporcelain common perf-kmem mainporcelain common perf-lock mainporcelain common perf-kvm mainporcelain common +perf-test mainporcelain common -- cgit v1.2.3