From mboxrd@z Thu Jan 1 00:00:00 1970 From: gregkh@linuxfoundation.org (gregkh at linuxfoundation.org) Date: Mon, 19 Nov 2018 12:05:35 +0100 Subject: Patch "perf cs-etm: Correct CPU mode for samples" has been added to the 4.19-stable tree Message-ID: <1542625535250192@kroah.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org This is a note to let you know that I've just added the patch titled perf cs-etm: Correct CPU mode for samples to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: perf-cs-etm-correct-cpu-mode-for-samples.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From d6c9c05fe1eb4b213b183d8a1e79416256dc833a Mon Sep 17 00:00:00 2001 From: Leo Yan Date: Tue, 30 Oct 2018 15:18:28 +0800 Subject: perf cs-etm: Correct CPU mode for samples From: Leo Yan commit d6c9c05fe1eb4b213b183d8a1e79416256dc833a upstream. Since commit edeb0c90df35 ("perf tools: Stop fallbacking to kallsyms for vdso symbols lookup"), the kernel address cannot be properly parsed to kernel symbol with command 'perf script -k vmlinux'. The reason is CoreSight samples is always to set CPU mode as PERF_RECORD_MISC_USER, thus it fails to find corresponding map/dso in below flows: process_sample_event() `-> machine__resolve() `-> thread__find_map(thread, sample->cpumode, sample->ip, al); In this flow it needs to pass argument 'sample->cpumode' to tell what's the CPU mode, before it always passed PERF_RECORD_MISC_USER but without any failure until the commit edeb0c90df35 ("perf tools: Stop fallbacking to kallsyms for vdso symbols lookup") has been merged. The reason is even with the wrong CPU mode the function thread__find_map() firstly fails to find map but it will rollback to find kernel map for vdso symbols lookup. In the latest code it has removed the fallback code, thus if CPU mode is PERF_RECORD_MISC_USER then it cannot find map anymore with kernel address. This patch is to correct samples CPU mode setting, it creates a new helper function cs_etm__cpu_mode() to tell what's the CPU mode based on the address with the info from machine structure; this patch has a bit extension to check not only kernel and user mode, but also check for host/guest and hypervisor mode. Finally this patch uses the function in instruction and branch samples and also apply in cs_etm__mem_access() for a minor polishing. Signed-off-by: Leo Yan Cc: Adrian Hunter Cc: Alexander Shishkin Cc: David Miller Cc: Jiri Olsa Cc: Mathieu Poirier Cc: Namhyung Kim Cc: Peter Zijlstra Cc: coresight at lists.linaro.org Cc: linux-arm-kernel at lists.infradead.org Cc: stable at kernel.org # v4.19 Link: http://lkml.kernel.org/r/1540883908-17018-1-git-send-email-leo.yan at linaro.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman --- tools/perf/util/cs-etm.c | 39 ++++++++++++++++++++++++++++++--------- 1 file changed, 30 insertions(+), 9 deletions(-) --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -244,6 +244,27 @@ static void cs_etm__free(struct perf_ses zfree(&aux); } +static u8 cs_etm__cpu_mode(struct cs_etm_queue *etmq, u64 address) +{ + struct machine *machine; + + machine = etmq->etm->machine; + + if (address >= etmq->etm->kernel_start) { + if (machine__is_host(machine)) + return PERF_RECORD_MISC_KERNEL; + else + return PERF_RECORD_MISC_GUEST_KERNEL; + } else { + if (machine__is_host(machine)) + return PERF_RECORD_MISC_USER; + else if (perf_guest) + return PERF_RECORD_MISC_GUEST_USER; + else + return PERF_RECORD_MISC_HYPERVISOR; + } +} + static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u64 address, size_t size, u8 *buffer) { @@ -258,10 +279,7 @@ static u32 cs_etm__mem_access(struct cs_ return -1; machine = etmq->etm->machine; - if (address >= etmq->etm->kernel_start) - cpumode = PERF_RECORD_MISC_KERNEL; - else - cpumode = PERF_RECORD_MISC_USER; + cpumode = cs_etm__cpu_mode(etmq, address); thread = etmq->thread; if (!thread) { @@ -653,7 +671,7 @@ static int cs_etm__synth_instruction_sam struct perf_sample sample = {.ip = 0,}; event->sample.header.type = PERF_RECORD_SAMPLE; - event->sample.header.misc = PERF_RECORD_MISC_USER; + event->sample.header.misc = cs_etm__cpu_mode(etmq, addr); event->sample.header.size = sizeof(struct perf_event_header); sample.ip = addr; @@ -665,7 +683,7 @@ static int cs_etm__synth_instruction_sam sample.cpu = etmq->packet->cpu; sample.flags = 0; sample.insn_len = 1; - sample.cpumode = event->header.misc; + sample.cpumode = event->sample.header.misc; if (etm->synth_opts.last_branch) { cs_etm__copy_last_branch_rb(etmq); @@ -706,12 +724,15 @@ static int cs_etm__synth_branch_sample(s u64 nr; struct branch_entry entries; } dummy_bs; + u64 ip; + + ip = cs_etm__last_executed_instr(etmq->prev_packet); event->sample.header.type = PERF_RECORD_SAMPLE; - event->sample.header.misc = PERF_RECORD_MISC_USER; + event->sample.header.misc = cs_etm__cpu_mode(etmq, ip); event->sample.header.size = sizeof(struct perf_event_header); - sample.ip = cs_etm__last_executed_instr(etmq->prev_packet); + sample.ip = ip; sample.pid = etmq->pid; sample.tid = etmq->tid; sample.addr = cs_etm__first_executed_instr(etmq->packet); @@ -720,7 +741,7 @@ static int cs_etm__synth_branch_sample(s sample.period = 1; sample.cpu = etmq->packet->cpu; sample.flags = 0; - sample.cpumode = PERF_RECORD_MISC_USER; + sample.cpumode = event->sample.header.misc; /* * perf report cannot handle events without a branch stack Patches currently in stable-queue which might be from leo.yan at linaro.org are queue-4.19/perf-cs-etm-correct-cpu-mode-for-samples.patch queue-4.19/perf-intel-pt-bts-calculate-cpumode-for-synthesized-samples.patch queue-4.19/perf-intel-pt-insert-callchain-context-into-synthesized-callchains.patch