To pick up the changes in:
e7862eda309ecfcc ("x86/cpu: Support AMD Automatic IBRS")
0125acda7d76b943 ("x86/bugs: Reset speculation control settings on init")
38aaf921e92dc5cf ("perf/x86: Add Meteor Lake support")
5b6fac3fa44bafee ("x86/resctrl: Detect and configure Slow Memory Bandwidth Allocation")
dc2a3e857981f859 ("x86/resctrl: Add interface to read mbm_total_bytes_config")
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 2023-03-03 18:26:51.
766923522 -0300
+++ after 2023-03-03 18:27:09.
987415481 -0300
@@ -267,9 +267,11 @@
[0xc000010e - x86_64_specific_MSRs_offset] = "AMD64_LBR_SELECT",
[0xc000010f - x86_64_specific_MSRs_offset] = "AMD_DBG_EXTN_CFG",
[0xc0000200 - x86_64_specific_MSRs_offset] = "IA32_MBA_BW_BASE",
+ [0xc0000280 - x86_64_specific_MSRs_offset] = "IA32_SMBA_BW_BASE",
[0xc0000300 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_STATUS",
[0xc0000301 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_CTL",
[0xc0000302 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_STATUS_CLR",
+ [0xc0000400 - x86_64_specific_MSRs_offset] = "IA32_EVT_CFG_BASE",
};
#define x86_AMD_V_KVM_MSRs_offset 0xc0010000
$
Now one can trace systemwide asking to see backtraces to where that MSR
is being read/written, see this example with a previous update:
# perf trace -e msr:*_msr/max-stack=32/ --filter="msr>=IA32_U_CET && msr<=IA32_INT_SSP_TAB"
^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>=IA32_U_CET && msr<=IA32_INT_SSP_TAB"
Using CPUID AuthenticAMD-25-21-0
0x6a0
0x6a8
New filter for msr:read_msr: (msr>=0x6a0 && msr<=0x6a8) && (common_pid != 597499 && common_pid != 3313)
0x6a0
0x6a8
New filter for msr:write_msr: (msr>=0x6a0 && msr<=0x6a8) && (common_pid != 597499 && common_pid != 3313)
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: Babu Moger <babu.moger@amd.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Breno Leitao <leitao@debian.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nikunj A Dadhania <nikunj@amd.com>
Link: https://lore.kernel.org/lkml/ZAJoaZ41+rU5H0vL@kernel.org
[ I had published the perf-tools branch before with the sync with ]
[
8c29f01654053258 ("x86/sev: Add SEV-SNP guest feature negotiation support") ]
[ I removed it from this new sync ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
#define _EFER_SVME 12 /* Enable virtualization */
#define _EFER_LMSLE 13 /* Long Mode Segment Limit Enable */
#define _EFER_FFXSR 14 /* Enable Fast FXSAVE/FXRSTOR */
+#define _EFER_AUTOIBRS 21 /* Enable Automatic IBRS */
#define EFER_SCE (1<<_EFER_SCE)
#define EFER_LME (1<<_EFER_LME)
#define EFER_SVME (1<<_EFER_SVME)
#define EFER_LMSLE (1<<_EFER_LMSLE)
#define EFER_FFXSR (1<<_EFER_FFXSR)
+#define EFER_AUTOIBRS (1<<_EFER_AUTOIBRS)
/* Intel MSRs. Some also available on other CPUs */
#define SPEC_CTRL_RRSBA_DIS_S_SHIFT 6 /* Disable RRSBA behavior */
#define SPEC_CTRL_RRSBA_DIS_S BIT(SPEC_CTRL_RRSBA_DIS_S_SHIFT)
+/* A mask for bits which the kernel toggles when controlling mitigations */
+#define SPEC_CTRL_MITIGATIONS_MASK (SPEC_CTRL_IBRS | SPEC_CTRL_STIBP | SPEC_CTRL_SSBD \
+ | SPEC_CTRL_RRSBA_DIS_S)
+
#define MSR_IA32_PRED_CMD 0x00000049 /* Prediction Command */
#define PRED_CMD_IBPB BIT(0) /* Indirect Branch Prediction Barrier */
#define MSR_TURBO_RATIO_LIMIT1 0x000001ae
#define MSR_TURBO_RATIO_LIMIT2 0x000001af
+#define MSR_SNOOP_RSP_0 0x00001328
+#define MSR_SNOOP_RSP_1 0x00001329
+
#define MSR_LBR_SELECT 0x000001c8
#define MSR_LBR_TOS 0x000001c9
/* - AMD: */
#define MSR_IA32_MBA_BW_BASE 0xc0000200
+#define MSR_IA32_SMBA_BW_BASE 0xc0000280
+#define MSR_IA32_EVT_CFG_BASE 0xc0000400
/* MSR_IA32_VMX_MISC bits */
#define MSR_IA32_VMX_MISC_INTEL_PT (1ULL << 14)