[PATCH 09/25] perf intel-pt: Add gp registers to synthesized PEBS sample

Arnaldo Carvalho de Melo
2019-06-21T17:40:03Z

From: Adrian Hunter <adrian.hunter@intel.com>

Add general purpose register information from PEBS data in the Intel PT
trace to the synthesized PEBS sample.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20190610072803.10456-8-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/intel-pt.c | 69 ++++++++++++++++++++++++++++++++++++++
1 file changed, 69 insertions(+)

diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
index 979519b00a74..00c2c96bb805 100644
--- a/tools/perf/util/intel-pt.c
+++ b/tools/perf/util/intel-pt.c
@@ -35,6 +35,8 @@
#include "config.h"
#include "time-utils.h"

+#include "../arch/x86/include/uapi/asm/perf_regs.h"
+
#include "intel-pt-decoder/intel-pt-log.h"
#include "intel-pt-decoder/intel-pt-decoder.h"
#include "intel-pt-decoder/intel-pt-insn-decoder.h"
@@ -1547,6 +1549,60 @@ static int intel_pt_synth_pwrx_sample(struct intel_pt_queue *ptq)
pt->pwr_events_sample_type);
}

+/*
+ * PEBS gp_regs array indexes plus 1 so that 0 means not present. Refer
+ * intel_pt_add_gp_regs().
+ */
+static const int pebs_gp_regs[] = {
+ [PERF_REG_X86_FLAGS] = 1,
+ [PERF_REG_X86_IP] = 2,
+ [PERF_REG_X86_AX] = 3,
+ [PERF_REG_X86_CX] = 4,
+ [PERF_REG_X86_DX] = 5,
+ [PERF_REG_X86_BX] = 6,
+ [PERF_REG_X86_SP] = 7,
+ [PERF_REG_X86_BP] = 8,
+ [PERF_REG_X86_SI] = 9,
+ [PERF_REG_X86_DI] = 10,
+ [PERF_REG_X86_R8] = 11,
+ [PERF_REG_X86_R9] = 12,
+ [PERF_REG_X86_R10] = 13,
+ [PERF_REG_X86_R11] = 14,
+ [PERF_REG_X86_R12] = 15,
+ [PERF_REG_X86_R13] = 16,
+ [PERF_REG_X86_R14] = 17,
+ [PERF_REG_X86_R15] = 18,
+};
+
+static u64 *intel_pt_add_gp_regs(struct regs_dump *intr_regs, u64 *pos,
+ const struct intel_pt_blk_items *items,
+ u64 regs_mask)
+{
+ const u64 *gp_regs = items->val[INTEL_PT_GP_REGS_POS];
+ u32 mask = items->mask[INTEL_PT_GP_REGS_POS];
+ u32 bit;
+ int i;
+
+ for (i = 0, bit = 1; i < PERF_REG_X86_64_MAX; i++, bit <<= 1) {
+ /* Get the PEBS gp_regs array index */
+ int n = pebs_gp_regs[i] - 1;
+
+ if (n < 0)
+ continue;
+ /*
+ * Add only registers that were requested (i.e. 'regs_mask') and
+ * that were provided (i.e. 'mask'), and update the resulting
+ * mask (i.e. 'intr_regs->mask') accordingly.
+ */
+ if (mask & 1 << n && regs_mask & bit) {
+ intr_regs->mask |= bit;
+ *pos++ = gp_regs[n];
+ }
+ }
+
+ return pos;
+}
+
static int intel_pt_synth_pebs_sample(struct intel_pt_queue *ptq)
{
const struct intel_pt_blk_items *items = &ptq->state->items;
@@ -1597,6 +1653,19 @@ static int intel_pt_synth_pebs_sample(struct intel_pt_queue *ptq)
sample.time = tsc_to_perf_time(timestamp, &pt->tc);
}

+ if (sample_type & PERF_SAMPLE_REGS_INTR &&
+ items->mask[INTEL_PT_GP_REGS_POS]) {
+ u64 regs[sizeof(sample.intr_regs.mask)];
+ u64 regs_mask = evsel->attr.sample_regs_intr;
+
+ sample.intr_regs.abi = items->is_32_bit ?
+ PERF_SAMPLE_REGS_ABI_32 :
+ PERF_SAMPLE_REGS_ABI_64;
+ sample.intr_regs.regs = regs;
+
+ intel_pt_add_gp_regs(&sample.intr_regs, regs, items, regs_mask);
+ }
+
return intel_pt_deliver_synth_event(pt, ptq, event, &sample, sample_type);
}

--
2.20.1