diff options
| -rw-r--r-- | tools/perf/Documentation/perf-intel-pt.txt | 70 | ||||
| -rw-r--r-- | tools/perf/util/intel-pt.c | 20 |
2 files changed, 88 insertions, 2 deletions
diff --git a/tools/perf/Documentation/perf-intel-pt.txt b/tools/perf/Documentation/perf-intel-pt.txt index 8acd704e8a39..238ab9d3cb93 100644 --- a/tools/perf/Documentation/perf-intel-pt.txt +++ b/tools/perf/Documentation/perf-intel-pt.txt @@ -1400,6 +1400,76 @@ There were none. :17006 17006 [001] 11500.262869216: ffffffff8220116e error_entry+0xe ([guest.kernel.kallsyms]) pushq %rax +Tracing Virtual Machines - Guest Code +------------------------------------- + +A common case for KVM test programs is that the test program acts as the +hypervisor, creating, running and destroying the virtual machine, and +providing the guest object code from its own object code. In this case, +the VM is not running an OS, but only the functions loaded into it by the +hypervisor test program, and conveniently, loaded at the same virtual +addresses. To support that, option "--guest-code" has been added to perf script +and perf kvm report. + +Here is an example tracing a test program from the kernel's KVM selftests: + + # perf record --kcore -e intel_pt/cyc/ -- tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test + [ perf record: Woken up 1 times to write data ] + [ perf record: Captured and wrote 0.280 MB perf.data ] + # perf script --guest-code --itrace=bep --ns -F-period,+addr,+flags + [SNIP] + tsc_msrs_test 18436 [007] 10897.962087733: branches: call ffffffffc13b2ff5 __vmx_vcpu_run+0x15 (vmlinux) => ffffffffc13b2f50 vmx_update_host_rsp+0x0 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962087733: branches: return ffffffffc13b2f5d vmx_update_host_rsp+0xd (vmlinux) => ffffffffc13b2ffa __vmx_vcpu_run+0x1a (vmlinux) + tsc_msrs_test 18436 [007] 10897.962087733: branches: call ffffffffc13b303b __vmx_vcpu_run+0x5b (vmlinux) => ffffffffc13b2f80 vmx_vmenter+0x0 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962087836: branches: vmentry ffffffffc13b2f82 vmx_vmenter+0x2 (vmlinux) => 0 [unknown] ([unknown]) + [guest/18436] 18436 [007] 10897.962087836: branches: vmentry 0 [unknown] ([unknown]) => 402c81 guest_code+0x131 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) + [guest/18436] 18436 [007] 10897.962087836: branches: call 402c81 guest_code+0x131 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) => 40dba0 ucall+0x0 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) + [guest/18436] 18436 [007] 10897.962088248: branches: vmexit 40dba0 ucall+0x0 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) => 0 [unknown] ([unknown]) + tsc_msrs_test 18436 [007] 10897.962088248: branches: vmexit 0 [unknown] ([unknown]) => ffffffffc13b2fa0 vmx_vmexit+0x0 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962088248: branches: jmp ffffffffc13b2fa0 vmx_vmexit+0x0 (vmlinux) => ffffffffc13b2fd2 vmx_vmexit+0x32 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962088256: branches: return ffffffffc13b2fd2 vmx_vmexit+0x32 (vmlinux) => ffffffffc13b3040 __vmx_vcpu_run+0x60 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962088270: branches: return ffffffffc13b30b6 __vmx_vcpu_run+0xd6 (vmlinux) => ffffffffc13b2f2e vmx_vcpu_enter_exit+0x4e (vmlinux) + [SNIP] + tsc_msrs_test 18436 [007] 10897.962089321: branches: call ffffffffc13b2ff5 __vmx_vcpu_run+0x15 (vmlinux) => ffffffffc13b2f50 vmx_update_host_rsp+0x0 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962089321: branches: return ffffffffc13b2f5d vmx_update_host_rsp+0xd (vmlinux) => ffffffffc13b2ffa __vmx_vcpu_run+0x1a (vmlinux) + tsc_msrs_test 18436 [007] 10897.962089321: branches: call ffffffffc13b303b __vmx_vcpu_run+0x5b (vmlinux) => ffffffffc13b2f80 vmx_vmenter+0x0 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962089424: branches: vmentry ffffffffc13b2f82 vmx_vmenter+0x2 (vmlinux) => 0 [unknown] ([unknown]) + [guest/18436] 18436 [007] 10897.962089424: branches: vmentry 0 [unknown] ([unknown]) => 40dba0 ucall+0x0 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) + [guest/18436] 18436 [007] 10897.962089701: branches: jmp 40dc1b ucall+0x7b (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) => 40dc39 ucall+0x99 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) + [guest/18436] 18436 [007] 10897.962089701: branches: jcc 40dc3c ucall+0x9c (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) => 40dc20 ucall+0x80 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) + [guest/18436] 18436 [007] 10897.962089701: branches: jcc 40dc3c ucall+0x9c (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) => 40dc20 ucall+0x80 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) + [guest/18436] 18436 [007] 10897.962089701: branches: jcc 40dc37 ucall+0x97 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) => 40dc50 ucall+0xb0 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) + [guest/18436] 18436 [007] 10897.962089878: branches: vmexit 40dc55 ucall+0xb5 (/home/user/git/work/tools/testing/selftests/kselftest_install/kvm/tsc_msrs_test) => 0 [unknown] ([unknown]) + tsc_msrs_test 18436 [007] 10897.962089878: branches: vmexit 0 [unknown] ([unknown]) => ffffffffc13b2fa0 vmx_vmexit+0x0 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962089878: branches: jmp ffffffffc13b2fa0 vmx_vmexit+0x0 (vmlinux) => ffffffffc13b2fd2 vmx_vmexit+0x32 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962089887: branches: return ffffffffc13b2fd2 vmx_vmexit+0x32 (vmlinux) => ffffffffc13b3040 __vmx_vcpu_run+0x60 (vmlinux) + tsc_msrs_test 18436 [007] 10897.962089901: branches: return ffffffffc13b30b6 __vmx_vcpu_run+0xd6 (vmlinux) => ffffffffc13b2f2e vmx_vcpu_enter_exit+0x4e (vmlinux) + [SNIP] + + # perf kvm --guest-code --guest --host report -i perf.data --stdio | head -20 + + # To display the perf.data header info, please use --header/--header-only options. + # + # + # Total Lost Samples: 0 + # + # Samples: 12 of event 'instructions' + # Event count (approx.): 2274583 + # + # Children Self Command Shared Object Symbol + # ........ ........ ............. .................... ........................................... + # + 54.70% 0.00% tsc_msrs_test [kernel.vmlinux] [k] entry_SYSCALL_64_after_hwframe + | + ---entry_SYSCALL_64_after_hwframe + do_syscall_64 + | + |--29.44%--syscall_exit_to_user_mode + | exit_to_user_mode_prepare + | task_work_run + | __fput + + Event Trace ----------- diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c index c7e115fefe7d..62b2f375a94d 100644 --- a/tools/perf/util/intel-pt.c +++ b/tools/perf/util/intel-pt.c @@ -192,6 +192,7 @@ struct intel_pt_queue { pid_t next_tid; struct thread *thread; struct machine *guest_machine; + struct thread *guest_thread; struct thread *unknown_guest_thread; pid_t guest_machine_pid; bool exclude_kernel; @@ -690,6 +691,11 @@ static int intel_pt_get_guest(struct intel_pt_queue *ptq) ptq->guest_machine = NULL; thread__zput(ptq->unknown_guest_thread); + if (symbol_conf.guest_code) { + thread__zput(ptq->guest_thread); + ptq->guest_thread = machines__findnew_guest_code(machines, pid); + } + machine = machines__find_guest(machines, pid); if (!machine) return -1; @@ -753,11 +759,16 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn, cpumode = intel_pt_nr_cpumode(ptq, *ip, nr); if (nr) { - if (cpumode != PERF_RECORD_MISC_GUEST_KERNEL || + if ((!symbol_conf.guest_code && cpumode != PERF_RECORD_MISC_GUEST_KERNEL) || intel_pt_get_guest(ptq)) return -EINVAL; machine = ptq->guest_machine; - thread = ptq->unknown_guest_thread; + thread = ptq->guest_thread; + if (!thread) { + if (cpumode != PERF_RECORD_MISC_GUEST_KERNEL) + return -EINVAL; + thread = ptq->unknown_guest_thread; + } } else { thread = ptq->thread; if (!thread) { @@ -1335,6 +1346,7 @@ static void intel_pt_free_queue(void *priv) if (!ptq) return; thread__zput(ptq->thread); + thread__zput(ptq->guest_thread); thread__zput(ptq->unknown_guest_thread); intel_pt_decoder_free(ptq->decoder); zfree(&ptq->event_buf); @@ -2407,6 +2419,10 @@ static int intel_pt_sample(struct intel_pt_queue *ptq) ptq->sample_ipc = ptq->state->flags & INTEL_PT_SAMPLE_IPC; } + /* Ensure guest code maps are set up */ + if (symbol_conf.guest_code && (state->from_nr || state->to_nr)) + intel_pt_get_guest(ptq); + /* * Do PEBS first to allow for the possibility that the PEBS timestamp * precedes the current timestamp. |