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bpftool: Add {i,d}tlb_misses support for bpftool profile

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Commit 47c09d6a9f67("bpftool: Introduce "prog profile" command")
introduced "bpftool prog profile" command which can be used
to profile bpf program with metrics like # of instructions,

This patch added support for itlb_misses and dtlb_misses.
During an internal bpf program performance evaluation,
I found these two metrics are also very useful. The following
is an example output:

 $ bpftool prog profile id 324 duration 3 cycles itlb_misses

           1885029 run_cnt
        5134686073 cycles
            306893 itlb_misses

 $ bpftool prog profile id 324 duration 3 cycles dtlb_misses

           1827382 run_cnt
        4943593648 cycles
           5975636 dtlb_misses

 $ bpftool prog profile id 324 duration 3 cycles llc_misses

           1836527 run_cnt
        5019612972 cycles
           4161041 llc_misses

From the above, we can see quite some dtlb misses, 3 dtlb misses
perf prog run. This might be something worth further investigation.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201119073039.4060095-1-yhs@fb.com
This commit is contained in:
Yonghong Song 2020-11-18 23:30:39 -08:00 committed by Daniel Borkmann
parent 4e99d115d8
commit 450d060e8f
1 changed files with 29 additions and 1 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

30
tools/bpf/bpftool/prog.c
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@ -1717,6 +1717,34 @@ struct profile_metric {
.ratio_desc = "LLC misses per million insns", .ratio_desc = "LLC misses per million insns",
.ratio_mul = 1e6, .ratio_mul = 1e6,
}, },
{
.name = "itlb_misses",
.attr = {
.type = PERF_TYPE_HW_CACHE,
.config =
PERF_COUNT_HW_CACHE_ITLB |
(PERF_COUNT_HW_CACHE_OP_READ << 8) |
(PERF_COUNT_HW_CACHE_RESULT_MISS << 16),
.exclude_user = 1
},
.ratio_metric = 2,
.ratio_desc = "itlb misses per million insns",
.ratio_mul = 1e6,
},
{
.name = "dtlb_misses",
.attr = {
.type = PERF_TYPE_HW_CACHE,
.config =
PERF_COUNT_HW_CACHE_DTLB |
(PERF_COUNT_HW_CACHE_OP_READ << 8) |
(PERF_COUNT_HW_CACHE_RESULT_MISS << 16),
.exclude_user = 1
},
.ratio_metric = 2,
.ratio_desc = "dtlb misses per million insns",
.ratio_mul = 1e6,
},
}; };
static __u64 profile_total_count; static __u64 profile_total_count;
@ -2109,7 +2137,7 @@ static int do_help(int argc, char **argv)
" struct_ops | fentry | fexit | freplace | sk_lookup }\n" " struct_ops | fentry | fexit | freplace | sk_lookup }\n"
" ATTACH_TYPE := { msg_verdict | stream_verdict | stream_parser |\n" " ATTACH_TYPE := { msg_verdict | stream_verdict | stream_parser |\n"
" flow_dissector }\n" " flow_dissector }\n"
" METRIC := { cycles | instructions | l1d_loads | llc_misses }\n" " METRIC := { cycles | instructions | l1d_loads | llc_misses | itlb_misses | dtlb_misses }\n"
" " HELP_SPEC_OPTIONS "\n" " " HELP_SPEC_OPTIONS "\n"
"", "",
bin_name, argv[-2]); bin_name, argv[-2]);