Re: [PATCH 1/1 FYI] tools arch x86: Sync the msr-index.h copy with the kernel sources
From: Rafael J. Wysocki
Date: Thu Jan 13 2022 - 14:14:50 EST
On 1/13/2022 3:25 PM, Arnaldo Carvalho de Melo wrote:
To pick up the changes in:
89aa94b4a218339b ("x86/msr: Add AMD CPPC MSR definitions")
Addressing these tools/perf build warnings:
diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h
Warning: Kernel ABI header at 'tools/arch/x86/include/asm/msr-index.h' differs from latest version at 'arch/x86/include/asm/msr-index.h'
That makes the beautification scripts to pick some new entries:
$ tools/perf/trace/beauty/tracepoints/x86_msr.sh > before
$ cp arch/x86/include/asm/msr-index.h tools/arch/x86/include/asm/msr-index.h
$ tools/perf/trace/beauty/tracepoints/x86_msr.sh > after
$ diff -u before after
--- before 2022-01-13 10:59:51.743416890 -0300
+++ after 2022-01-13 11:00:00.776644178 -0300
@@ -303,6 +303,11 @@
[0xc0010299 - x86_AMD_V_KVM_MSRs_offset] = "AMD_RAPL_POWER_UNIT",
[0xc001029a - x86_AMD_V_KVM_MSRs_offset] = "AMD_CORE_ENERGY_STATUS",
[0xc001029b - x86_AMD_V_KVM_MSRs_offset] = "AMD_PKG_ENERGY_STATUS",
+ [0xc00102b0 - x86_AMD_V_KVM_MSRs_offset] = "AMD_CPPC_CAP1",
+ [0xc00102b1 - x86_AMD_V_KVM_MSRs_offset] = "AMD_CPPC_ENABLE",
+ [0xc00102b2 - x86_AMD_V_KVM_MSRs_offset] = "AMD_CPPC_CAP2",
+ [0xc00102b3 - x86_AMD_V_KVM_MSRs_offset] = "AMD_CPPC_REQ",
+ [0xc00102b4 - x86_AMD_V_KVM_MSRs_offset] = "AMD_CPPC_STATUS",
[0xc00102f0 - x86_AMD_V_KVM_MSRs_offset] = "AMD_PPIN_CTL",
[0xc00102f1 - x86_AMD_V_KVM_MSRs_offset] = "AMD_PPIN",
};
$
And this gets rebuilt:
CC /tmp/build/perf/trace/beauty/tracepoints/x86_msr.o
INSTALL trace_plugins
LD /tmp/build/perf/trace/beauty/tracepoints/perf-in.o
LD /tmp/build/perf/trace/beauty/perf-in.o
LD /tmp/build/perf/perf-in.o
LINK /tmp/build/perf/perf
Now one can trace systemwide asking to see backtraces to where those
MSRs are being read/written with:
# perf trace -e msr:*_msr/max-stack=32/ --filter="msr>=AMD_CPPC_CAP1 && msr<="
Failed to set filter "(msr>=0xc00102b0 && msr<=) && (common_pid != 2612094 && common_pid != 3841)" on event msr:read_msr with 22 (Invalid argument)
# ^C
If we use -v (verbose mode) we can see what it does behind the scenes:
# perf trace -v -e msr:*_msr/max-stack=32/ --filter="msr>=AMD_CPPC_CAP1 && msr<=AMD_CPPC_STATUS"
<SNIP>
New filter for msr:read_msr: (msr>=0xc00102b0 && msr<=0xc00102b4) && (common_pid != 2612102 && common_pid != 3841)
New filter for msr:write_msr: (msr>=0xc00102b0 && msr<=0xc00102b4) && (common_pid != 2612102 && common_pid != 3841)
<SNIP>
^C[root@five ~]#
Example with a frequent msr:
# perf trace -v -e msr:*_msr/max-stack=32/ --filter="msr==IA32_SPEC_CTRL" --max-events 2
Using CPUID AuthenticAMD-25-21-0
0x48
New filter for msr:read_msr: (msr==0x48) && (common_pid != 2612129 && common_pid != 3841)
0x48
New filter for msr:write_msr: (msr==0x48) && (common_pid != 2612129 && common_pid != 3841)
mmap size 528384B
Looking at the vmlinux_path (8 entries long)
symsrc__init: build id mismatch for vmlinux.
Using /proc/kcore for kernel data
Using /proc/kallsyms for symbols
0.000 Timer/2525383 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
do_trace_write_msr ([kernel.kallsyms])
do_trace_write_msr ([kernel.kallsyms])
__switch_to_xtra ([kernel.kallsyms])
__switch_to ([kernel.kallsyms])
__schedule ([kernel.kallsyms])
schedule ([kernel.kallsyms])
futex_wait_queue_me ([kernel.kallsyms])
futex_wait ([kernel.kallsyms])
do_futex ([kernel.kallsyms])
__x64_sys_futex ([kernel.kallsyms])
do_syscall_64 ([kernel.kallsyms])
entry_SYSCALL_64_after_hwframe ([kernel.kallsyms])
__futex_abstimed_wait_common64 (/usr/lib64/libpthread-2.33.so)
0.030 :0/0 msr:write_msr(msr: IA32_SPEC_CTRL, val: 2)
do_trace_write_msr ([kernel.kallsyms])
do_trace_write_msr ([kernel.kallsyms])
__switch_to_xtra ([kernel.kallsyms])
__switch_to ([kernel.kallsyms])
__schedule ([kernel.kallsyms])
schedule_idle ([kernel.kallsyms])
do_idle ([kernel.kallsyms])
cpu_startup_entry ([kernel.kallsyms])
secondary_startup_64_no_verify ([kernel.kallsyms])
#
Cc: Huang Rui <ray.huang@xxxxxxx>
Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
tools/arch/x86/include/asm/msr-index.h | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/tools/arch/x86/include/asm/msr-index.h b/tools/arch/x86/include/asm/msr-index.h
index 01e2650b958591e0..3faf0f97edb1bcd3 100644
--- a/tools/arch/x86/include/asm/msr-index.h
+++ b/tools/arch/x86/include/asm/msr-index.h
@@ -486,6 +486,23 @@
#define MSR_AMD64_VIRT_SPEC_CTRL 0xc001011f
+/* AMD Collaborative Processor Performance Control MSRs */
+#define MSR_AMD_CPPC_CAP1 0xc00102b0
+#define MSR_AMD_CPPC_ENABLE 0xc00102b1
+#define MSR_AMD_CPPC_CAP2 0xc00102b2
+#define MSR_AMD_CPPC_REQ 0xc00102b3
+#define MSR_AMD_CPPC_STATUS 0xc00102b4
+
+#define AMD_CPPC_LOWEST_PERF(x) (((x) >> 0) & 0xff)
+#define AMD_CPPC_LOWNONLIN_PERF(x) (((x) >> 8) & 0xff)
+#define AMD_CPPC_NOMINAL_PERF(x) (((x) >> 16) & 0xff)
+#define AMD_CPPC_HIGHEST_PERF(x) (((x) >> 24) & 0xff)
+
+#define AMD_CPPC_MAX_PERF(x) (((x) & 0xff) << 0)
+#define AMD_CPPC_MIN_PERF(x) (((x) & 0xff) << 8)
+#define AMD_CPPC_DES_PERF(x) (((x) & 0xff) << 16)
+#define AMD_CPPC_ENERGY_PERF_PREF(x) (((x) & 0xff) << 24)
+
/* Fam 17h MSRs */
#define MSR_F17H_IRPERF 0xc00000e9