perf report: Fix wrong jump arrow
When we use perf report interactive annotate view, we can see the position of jump arrow is not correct. For example, 1. perf record -b ... 2. perf report 3. In interactive mode, select Annotate 'function' Percent│ IPC Cycle │ if (flag) 1.37 │0.4┌── 1 ↓ je 82 │ │ x += x / y + y / x; 0.00 │0.4│ 1310 movsd (%rsp),%xmm0 0.00 │0.4│ 565 movsd 0x8(%rsp),%xmm4 │0.4│ movsd 0x8(%rsp),%xmm1 │0.4│ movsd (%rsp),%xmm3 │0.4│ divsd %xmm4,%xmm0 0.00 │0.4│ 579 divsd %xmm3,%xmm1 │0.4│ movsd (%rsp),%xmm2 │0.4│ addsd %xmm1,%xmm0 │0.4│ addsd %xmm2,%xmm0 0.00 │0.4│ movsd %xmm0,(%rsp) │ │ volatile double x = 1212121212, y = 121212; │ │ │ │ s_randseed = time(0); │ │ srand(s_randseed); │ │ │ │ for (i = 0; i < 2000000000; i++) { 1.37 │0.4└─→ 82: sub $0x1,%ebx 28.21 │0.48 17 ↑ jne 38 The jump arrow in above example is not correct. It should add the width of IPC and Cycle. With this patch, the result is: Percent│ IPC Cycle │ if (flag) 1.37 │0.48 1 ┌──je 82 │ │ x += x / y + y / x; 0.00 │0.48 1310 │ movsd (%rsp),%xmm0 0.00 │0.48 565 │ movsd 0x8(%rsp),%xmm4 │0.48 │ movsd 0x8(%rsp),%xmm1 │0.48 │ movsd (%rsp),%xmm3 │0.48 │ divsd %xmm4,%xmm0 0.00 │0.48 579 │ divsd %xmm3,%xmm1 │0.48 │ movsd (%rsp),%xmm2 │0.48 │ addsd %xmm1,%xmm0 │0.48 │ addsd %xmm2,%xmm0 0.00 │0.48 │ movsd %xmm0,(%rsp) │ │ volatile double x = 1212121212, y = 121212; │ │ │ │ s_randseed = time(0); │ │ srand(s_randseed); │ │ │ │ for (i = 0; i < 2000000000; i++) { 1.37 │0.48 82:└─→sub $0x1,%ebx 28.21 │0.48 17 ↑ jne 38 Committer notes: Please note that only from LBRv5 (according to Jiri) onwards, i.e. >= Skylake is that we'll have the cycles counts in each branch record entry, so to see the Cycles and IPC columns, and be able to test this patch, one need a capable hardware. While applying this I first tested it on a Broadwell class machine and couldn't get those columns, will add code to the annotate browser to warn the user about that, i.e. you have branch records, but no cycles, use a more recent hardware to get the cycles and IPC columns. Signed-off-by: Jin Yao <yao.jin@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jin Yao <yao.jin@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1517223473-14750-1-git-send-email-yao.jin@linux.intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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