Re: [PATCH V1 00/19] perf tools and x86 PTI entry trampolines

[Jiri Olsa]

On Tue, May 15, 2018 at 03:43:14PM +0300, Adrian Hunter wrote:

SNIP

> 
>  # Overhead  Command    Shared Object     Symbol
>  # ........  .........  ................  ..................................
>  #
>     41.91%  uname_x_n  [kernel.vmlinux]  [k] syscall_return_via_sysret
>     24.70%  uname_x_n  [kernel.vmlinux]  [k] entry_SYSCALL_64_trampoline
>     19.22%  uname_x_n  [kernel.vmlinux]  [k] copy_user_enhanced_fast_string
>      4.09%  uname_x_n  libc-2.19.so      [.] __GI___uname
>      3.08%  uname_x_n  [kernel.vmlinux]  [k] do_syscall_64
>      2.32%  uname_x_n  [kernel.vmlinux]  [k] down_read
>      2.27%  uname_x_n  ld-2.19.so        [.] _dl_start
>      1.25%  uname_x_n  [kernel.vmlinux]  [k] up_read
>      0.99%  uname_x_n  [kernel.vmlinux]  [k] entry_SYSCALL_64
>      0.16%  uname_x_n  [kernel.vmlinux]  [k] flush_signal_handlers
>      0.01%  perf       [kernel.vmlinux]  [k] native_sched_clock
>      0.00%  perf       [kernel.vmlinux]  [k] native_write_msr
> 
> 
> Adrian Hunter (17):
>       kallsyms: Simplify update_iter_mod()
>       x86: kcore: Give entry trampolines all the same offset in kcore
>       perf tools: Use the _stest symbol to identify the kernel map when loading kcore
>       perf tools: Fix kernel_start for PTI on x86
>       perf tools: Workaround missing maps for x86 PTI entry trampolines
>       perf tools: Fix map_groups__split_kallsyms() for entry trampoline symbols
>       perf tools: Allow for extra kernel maps
>       perf tools: Create maps for x86 PTI entry trampolines
>       perf tools: Synthesize and process mmap events for x86 PTI entry trampolines

the perf tools patches look good to me:

    Acked-and-tested-by: Jiri Olsa <jolsa@xxxxxxxxxx>

jirka

>       perf buildid-cache: kcore_copy: Keep phdr data in a list
>       perf buildid-cache: kcore_copy: Keep a count of phdrs
>       perf buildid-cache: kcore_copy: Calculate offset from phnum
>       perf buildid-cache: kcore_copy: Layout sections
>       perf buildid-cache: kcore_copy: Iterate phdrs
>       perf buildid-cache: kcore_copy: Get rid of kernel_map
>       perf buildid-cache: kcore_copy: Copy x86 PTI entry trampoline sections
>       perf buildid-cache: kcore_copy: Amend the offset of sections that remap kernel text