Hi Catalin, Will, On Tue, May 19, 2015 at 6:52 PM, Catalin Marinas <[email protected]> wrote: > On Sun, May 10, 2015 at 11:07:40AM +0000, Hou Pengyang wrote: >> For ARM64, when tracing with tracepoint events, the IP and pstate are set >> to 0, preventing the perf code parsing the callchain and resolving the >> symbols correctly. >> >> ./perf record -e sched:sched_switch -g --call-graph dwarf ls >> [ perf record: Captured and wrote 0.146 MB perf.data ] >> ./perf report -f >> Samples: 194 of event 'sched:sched_switch', Event count (approx.): 194 >> Children Self Command Shared Object Symbol >> 100.00% 100.00% ls [unknown] [.] 0000000000000000 >> >> The fix is to implement perf_arch_fetch_caller_regs for ARM64, which fills >> several necessary registers used for callchain unwinding, including pc,sp, >> fp and spsr . >> >> With this patch, callchain can be parsed correctly as follows: >> >> ...... >> + 2.63% 0.00% ls [kernel.kallsyms] [k] vfs_symlink >> + 2.63% 0.00% ls [kernel.kallsyms] [k] follow_down >> + 2.63% 0.00% ls [kernel.kallsyms] [k] pfkey_get >> + 2.63% 0.00% ls [kernel.kallsyms] [k] >> do_execveat_common.isra.33 >> - 2.63% 0.00% ls [kernel.kallsyms] [k] >> pfkey_send_policy_notify >> pfkey_send_policy_notify >> pfkey_get >> v9fs_vfs_rename >> page_follow_link_light >> link_path_walk >> el0_svc_naked >> ....... >> >> Signed-off-by: Hou Pengyang <[email protected]> >> Acked-by: Will Deacon <[email protected]> > > Queued for 4.2. Thanks.
Nice to see this one going out, finally. Cheers, Jean > > -- > Catalin > > _______________________________________________ > linux-arm-kernel mailing list > [email protected] > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
