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Arnaldo Carvalho de Melo a3a365655a tools arch x86: Sync the msr-index.h copy with the kernel sources 
To pick up the changes in:

  b8d1d16360 ("x86/apic: Don't disable x2APIC if locked")
  ca5b7c0d96 ("perf/x86/amd/lbr: Add LbrExtV2 branch record support")

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	2022-10-14 18:06:34.294561729 -0300
  +++ after	2022-10-14 18:06:41.285744044 -0300
  @@ -264,6 +264,7 @@
   	[0xc0000102 - x86_64_specific_MSRs_offset] = "KERNEL_GS_BASE",
   	[0xc0000103 - x86_64_specific_MSRs_offset] = "TSC_AUX",
   	[0xc0000104 - x86_64_specific_MSRs_offset] = "AMD64_TSC_RATIO",
  +	[0xc000010e - x86_64_specific_MSRs_offset] = "AMD64_LBR_SELECT",
   	[0xc000010f - x86_64_specific_MSRs_offset] = "AMD_DBG_EXTN_CFG",
   	[0xc0000300 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_STATUS",
   	[0xc0000301 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_CTL",
  $

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: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sandipan Das <sandipan.das@amd.com>
Link: https://lore.kernel.org/lkml/Y0nQkz2TUJxwfXJd@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-10-15 10:13:16 -03:00
arch xen: branch for v6.1-rc1 2022-10-12 14:39:38 -07:00
block block-6.1-2022-10-13 2022-10-13 21:25:57 -07:00
certs certs: make system keyring depend on built-in x509 parser 2022-09-24 04:31:18 +09:00
crypto - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
Documentation Devicetree fixes for v6.1-rc, part 1: 2022-10-13 12:22:42 -07:00
drivers drm fixes for 6.1-rc1 2022-10-13 21:56:34 -07:00
fs A quiet round this time: several assorted filesystem fixes, the most 2022-10-13 10:21:37 -07:00
include block-6.1-2022-10-13 2022-10-13 21:25:57 -07:00
init - hfs and hfsplus kmap API modernization from Fabio Francesco 2022-10-12 11:00:22 -07:00
io_uring io_uring/rw: ensure kiocb_end_write() is always called 2022-10-12 16:30:56 -06:00
ipc - hfs and hfsplus kmap API modernization from Fabio Francesco 2022-10-12 11:00:22 -07:00
kernel Tracing fixes for 6.1: 2022-10-13 10:36:57 -07:00
lib linux-kselftest-kunit-6.1-rc1-2 2022-10-12 15:01:58 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm Five hotfixes - three for nilfs2, two for MM. For are cc:stable, one is 2022-10-12 11:16:58 -07:00
net io_uring-6.1-2022-10-13 2022-10-13 21:15:30 -07:00
rust Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
samples VFIO updates for v6.1-rc1 2022-10-12 14:46:48 -07:00
scripts - hfs and hfsplus kmap API modernization from Fabio Francesco 2022-10-12 11:00:22 -07:00
security - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
sound sound updates for 6.1-rc1 2022-10-05 12:02:07 -07:00
tools tools arch x86: Sync the msr-index.h copy with the kernel sources 2022-10-15 10:13:16 -03:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt VFIO updates for v6.1-rc1 2022-10-12 14:46:48 -07:00
.clang-format PCI/DOE: Add DOE mailbox support functions 2022-07-19 15:38:04 -07:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes
.gitignore Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap - hfs and hfsplus kmap API modernization from Fabio Francesco 2022-10-12 11:00:22 -07:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS drm for 5.20/6.0 2022-08-03 19:52:08 -07:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS block-6.1-2022-10-13 2022-10-13 21:25:57 -07:00
Makefile - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
README

README 

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.