[tip: perf/core] perf beauty: Introduce strtoul() for x86 MSRs

From: tip-bot2 for Arnaldo Carvalho de Melo
Date: Tue Oct 15 2019 - 01:32:16 EST


The following commit has been merged into the perf/core branch of tip:

Commit-ID: 728db198868c7b46db5e65717d4518aeb6523ccc
Gitweb: https://git.kernel.org/tip/728db198868c7b46db5e65717d4518aeb6523ccc
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Wed, 09 Oct 2019 16:25:02 -03:00
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitterDate: Wed, 09 Oct 2019 16:25:02 -03:00

perf beauty: Introduce strtoul() for x86 MSRs

Continuing from the previous cset comment, now that filter expression
works:

# perf trace -e msr:* --filter="msr!=FS_BASE && msr != IA32_TSC_DEADLINE && msr != 0x830 && msr != 0x83f && msr !=IA32_SPEC_CTRL" --filter-pids 3750
0.000 Timer/5033 msr:write_msr(msr: SYSCALL_MASK, val: 292608)
0.009 Timer/5033 msr:write_msr(msr: LSTAR, val: -1398800368)
0.010 Timer/5033 msr:write_msr(msr: TSC_AUX, val: 4)
0.050 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
45.661 gnome-terminal/12595 msr:write_msr(msr: SYSCALL_MASK, val: 292608)
45.672 gnome-terminal/12595 msr:write_msr(msr: LSTAR, val: -1398800368)
45.675 gnome-terminal/12595 msr:write_msr(msr: TSC_AUX, val: 3)
54.852 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
130.508 Timer/4050 msr:write_msr(msr: SYSCALL_MASK, val: 292608)
130.527 Timer/4050 msr:write_msr(msr: LSTAR, val: -1398800368)
130.531 Timer/4050 msr:write_msr(msr: TSC_AUX, val: 3)
140.924 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
164.738 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
603.578 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
620.809 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
690.115 JS Watchdog/4259 msr:write_msr(msr: SYSCALL_MASK, val: 292608)
690.136 JS Watchdog/4259 msr:write_msr(msr: LSTAR, val: -1398800368)
690.141 JS Watchdog/4259 msr:write_msr(msr: TSC_AUX, val: 3)
690.186 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
759.016 :0/0 msr:read_msr(msr: IA32_TSC_ADJUST)
^C[root@quaco ~]#

Or look at the first 3 write_msr events for that IA32_TSC_DEADLINE to learn why
it happens so often:

# perf trace --max-events=3 --max-stack=8 -e msr:* --filter="msr==IA32_TSC_DEADLINE" --filter-pids 3750
0.000 :0/0 msr:write_msr(msr: IA32_TSC_DEADLINE, val: 19296732550862)
do_trace_write_msr ([kernel.kallsyms])
do_trace_write_msr ([kernel.kallsyms])
lapic_next_deadline ([kernel.kallsyms])
clockevents_program_event ([kernel.kallsyms])
hrtimer_interrupt ([kernel.kallsyms])
smp_apic_timer_interrupt ([kernel.kallsyms])
apic_timer_interrupt ([kernel.kallsyms])
cpuidle_enter_state ([kernel.kallsyms])
32.646 :0/0 msr:write_msr(msr: IA32_TSC_DEADLINE, val: 19296800134158)
do_trace_write_msr ([kernel.kallsyms])
do_trace_write_msr ([kernel.kallsyms])
lapic_next_deadline ([kernel.kallsyms])
clockevents_program_event ([kernel.kallsyms])
hrtimer_start_range_ns ([kernel.kallsyms])
tick_nohz_restart_sched_tick ([kernel.kallsyms])
tick_nohz_idle_exit ([kernel.kallsyms])
do_idle ([kernel.kallsyms])
32.802 :0/0 msr:write_msr(msr: IA32_TSC_DEADLINE, val: 19297507436922)
do_trace_write_msr ([kernel.kallsyms])
do_trace_write_msr ([kernel.kallsyms])
lapic_next_deadline ([kernel.kallsyms])
clockevents_program_event ([kernel.kallsyms])
hrtimer_try_to_cancel ([kernel.kallsyms])
hrtimer_cancel ([kernel.kallsyms])
tick_nohz_restart_sched_tick ([kernel.kallsyms])
tick_nohz_idle_exit ([kernel.kallsyms])
#

And if some of the strings can't be found:

# trace -e msr:* --filter="msr!=SPECULATIVE_EXECUTION_PROBLEMS_SOLUTION && msr != IA32_TSC_DEADLINE && msr != 0x830 && msr != 0x83f && msr !=IA32_SPEC_CTRL" --filter-pids 3750
"SPECULATIVE_EXECUTION_PROBLEMS_SOLUTION" not found for "msr" in "msr:read_msr", can't set filter "(msr!=SPECULATIVE_EXECUTION_PROBLEMS_SOLUTION && msr != IA32_TSC_DEADLINE && msr != 0x830 && msr != 0x83f && msr !=IA32_SPEC_CTRL) && (common_pid != 28131 && common_pid != 3750)"
#

Next step is to automatically wire up the pre-existing strarrays, which there
are quite a few.

The strtoul() methods will be further enhanced to allow for looking at other
arguments in a syscall/tracepoint, just like going from integer to string
(scnprintf methods), so that those "val" lines for the msr tracepoints can be
properly formatted or even resolved into some string.

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Luis ClÃudio GonÃalves <lclaudio@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-4qaai5iqjgefd11k4ddm7qg8@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-trace.c | 2 +-
tools/perf/trace/beauty/beauty.h | 3 +++
tools/perf/trace/beauty/tracepoints/x86_msr.c | 5 +++++
3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 515a800..b627975 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -1512,7 +1512,7 @@ static int syscall__alloc_arg_fmts(struct syscall *sc, int nr_args)
}

static struct syscall_arg_fmt syscall_arg_fmts__by_name[] = {
- { .name = "msr", .scnprintf = SCA_X86_MSR, }
+ { .name = "msr", .scnprintf = SCA_X86_MSR, .strtoul = STUL_X86_MSR, }
};

static int syscall_arg_fmt__cmp(const void *name, const void *fmtp)
diff --git a/tools/perf/trace/beauty/beauty.h b/tools/perf/trace/beauty/beauty.h
index 919ac45..77ad80a 100644
--- a/tools/perf/trace/beauty/beauty.h
+++ b/tools/perf/trace/beauty/beauty.h
@@ -122,6 +122,9 @@ size_t syscall_arg__scnprintf_strarray_flags(char *bf, size_t size, struct sysca
size_t syscall_arg__scnprintf_x86_MSR(char *bf, size_t size, struct syscall_arg *arg);
#define SCA_X86_MSR syscall_arg__scnprintf_x86_MSR

+bool syscall_arg__strtoul_x86_MSR(char *bf, size_t size, struct syscall_arg *arg, u64 *ret);
+#define STUL_X86_MSR syscall_arg__strtoul_x86_MSR
+
size_t syscall_arg__scnprintf_strarrays(char *bf, size_t size, struct syscall_arg *arg);
#define SCA_STRARRAYS syscall_arg__scnprintf_strarrays

diff --git a/tools/perf/trace/beauty/tracepoints/x86_msr.c b/tools/perf/trace/beauty/tracepoints/x86_msr.c
index 5e9ef53..6b8f129 100644
--- a/tools/perf/trace/beauty/tracepoints/x86_msr.c
+++ b/tools/perf/trace/beauty/tracepoints/x86_msr.c
@@ -32,3 +32,8 @@ size_t syscall_arg__scnprintf_x86_MSR(char *bf, size_t size, struct syscall_arg

return x86_MSR__scnprintf(flags, bf, size, arg->show_string_prefix);
}
+
+bool syscall_arg__strtoul_x86_MSR(char *bf, size_t size, struct syscall_arg *arg __maybe_unused, u64 *ret)
+{
+ return strarrays__strtoul(&strarrays__x86_MSRs_tables, bf, size, ret);
+}