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Subject[PATCH 1/1 FYI] tools arch x86: Sync the msr-index.h copy with the kernel sources
Just FYI, I'm carrying this on my perf/urgent branch, resent to have
lkml on CC list so that I can add a Link: to the commit.

- Arnaldo

--

To pick up the changes in:

3915035282573c5e ("KVM: x86: SVM: move avic definitions from AMD's spec to svm.h")

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 2022-02-22 17:35:36.996271430 -0300
+++ after 2022-02-22 17:35:46.258503347 -0300
@@ -287,6 +287,7 @@
[0xc0010114 - x86_AMD_V_KVM_MSRs_offset] = "VM_CR",
[0xc0010115 - x86_AMD_V_KVM_MSRs_offset] = "VM_IGNNE",
[0xc0010117 - x86_AMD_V_KVM_MSRs_offset] = "VM_HSAVE_PA",
+ [0xc001011b - x86_AMD_V_KVM_MSRs_offset] = "AMD64_SVM_AVIC_DOORBELL",
[0xc001011e - x86_AMD_V_KVM_MSRs_offset] = "AMD64_VM_PAGE_FLUSH",
[0xc001011f - x86_AMD_V_KVM_MSRs_offset] = "AMD64_VIRT_SPEC_CTRL",
[0xc0010130 - x86_AMD_V_KVM_MSRs_offset] = "AMD64_SEV_ES_GHCB",
$
And this gets rebuilt:

CC /tmp/build/perf/trace/beauty/tracepoints/x86_msr.o
LD /tmp/build/perf/trace/beauty/tracepoints/perf-in.o
LD /tmp/build/perf/trace/beauty/perf-in.o
CC /tmp/build/perf/util/amd-sample-raw.o
LD /tmp/build/perf/util/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>=AMD64_SVM_AVIC_DOORBELL && msr<=AMD64_SEV_ES_GHCB"
^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>=AMD64_SVM_AVIC_DOORBELL && msr<=AMD64_SEV_ES_GHCB"
Using CPUID AuthenticAMD-25-21-0
0xc001011b
0xc0010130
New filter for msr:read_msr: (msr>=0xc001011b && msr<=0xc0010130) && (common_pid != 1019953 && common_pid != 3629)
0xc001011b
0xc0010130
New filter for msr:write_msr: (msr>=0xc001011b && msr<=0xc0010130) && (common_pid != 1019953 && common_pid != 3629)
mmap size 528384B
^C#

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: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/arch/x86/include/asm/msr-index.h | 1 +
1 file changed, 1 insertion(+)
diff --git a/tools/arch/x86/include/asm/msr-index.h b/tools/arch/x86/include/asm/msr-index.h
index 3faf0f97edb1bcd3..a4a39c3e0f196747 100644
--- a/tools/arch/x86/include/asm/msr-index.h
+++ b/tools/arch/x86/include/asm/msr-index.h
@@ -476,6 +476,7 @@
#define MSR_AMD64_ICIBSEXTDCTL 0xc001103c
#define MSR_AMD64_IBSOPDATA4 0xc001103d
#define MSR_AMD64_IBS_REG_COUNT_MAX 8 /* includes MSR_AMD64_IBSBRTARGET */
+#define MSR_AMD64_SVM_AVIC_DOORBELL 0xc001011b
#define MSR_AMD64_VM_PAGE_FLUSH 0xc001011e
#define MSR_AMD64_SEV_ES_GHCB 0xc0010130
#define MSR_AMD64_SEV 0xc0010131
--
2.34.1

----- End forwarded message -----
--

- Arnaldo

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