Messages in this thread Patch in this message | | | From | Leo Yan <> | Subject | [PATCH v2] perf machine: Fix load kernel symbol with '-k' option | Date | Fri, 9 Mar 2018 14:05:23 +0800 |
| |
On Hikey arm64 octa A53 platform, when use command './perf report -v -k vmlinux --stdio' it outputs below error info, and it skips to load kernel symbol and doesn't print symbol for event: Failed to open [kernel.kallsyms]_text, continuing without symbols.
The regression is introduced by commit ("8c7f1bb37b29 perf machine: Move kernel mmap name into struct machine"), which changes the logic for machine mmap_name by removing function machine__mmap_name() and always use 'machine->mmap_name'. Comparing difference between machine__mmap_name() and 'machine->mmap_name', the later one includes the string for specified kernel vmlinux string with option '-k' in command, but the old function machine__mmap_name() ignores vmlinux path string. As result, event's mmap file name doesn't match with machine mmap file name anymore and it skips to load kernel symbol from vmlinux file.
To resolve this issue, this patch adds extra checking for 'symbol_conf.vmlinux_name', when it has been set string so we can know it includes vmlinux path string specified for option '-k'. For this case it sets 'is_kernel_mmap' to true and run into flow to load kernel symbol from vmlinux.
This patch has been verified with two commands: './perf report -v -k vmlinux --stdio' and './perf script -v -F cpu,event,ip,sym,symoff -k vmlinux'.
Suggested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Leo Yan <leo.yan@linaro.org> --- tools/perf/util/machine.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 12b7427..3125871 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -1299,9 +1299,18 @@ static int machine__process_kernel_mmap_event(struct machine *machine, else kernel_type = DSO_TYPE_GUEST_KERNEL; - is_kernel_mmap = memcmp(event->mmap.filename, - machine->mmap_name, - strlen(machine->mmap_name) - 1) == 0; + /* + * When symbol_conf.vmlinux_name is not NULL, it includes the specified + * kernel vmlinux path with option '-k'. So set 'is_kernel_mmap' to + * true for creating machine symbol map. + */ + if (symbol_conf.vmlinux_name) + is_kernel_mmap = true; + else + is_kernel_mmap = memcmp(event->mmap.filename, + machine->mmap_name, + strlen(machine->mmap_name) - 1) == 0; + if (event->mmap.filename[0] == '/' || (!is_kernel_mmap && event->mmap.filename[0] == '[')) { map = machine__findnew_module_map(machine, event->mmap.start, -- 2.7.4
| |