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    SubjectRe: [PATCH v5 0/2] perf probe: add sdt probes arguments into the uprobe cmd string

    * Alexis Berlemont <alexis.berlemont@gmail.com> wrote:

    > Hi Masami,
    >
    > Many thanks for your mail.
    >
    > Here is another patch set which tries to fix the points you mentioned:
    >
    > * Skip the arguments containing a constant ($123);
    > * Review the code in charge of the register renaming (search for '%'
    > and parse it);
    > * Minor changes (print the argument in case of error, skipping, check
    > the sdt arg type index);
    >
    > Many thanks,
    >
    > Alexis.
    >
    > Alexis Berlemont (2):
    > perf sdt: add scanning of sdt probles arguments
    > perf probe: add sdt probes arguments into the uprobe cmd string

    I'd like to hijack this thread to report an SDT oddity - one of my boxen reports
    lots of SDT tracepoints in 'perf list':

    mem:<addr>[/len][:access] [Hardware breakpoint]

    sdt_libc:lll_lock_wait_private [SDT event]
    sdt_libc:longjmp [SDT event]
    sdt_libc:longjmp_target [SDT event]
    sdt_libc:memory_arena_new [SDT event]
    sdt_libc:memory_arena_retry [SDT event]
    sdt_libc:memory_arena_reuse [SDT event]
    sdt_libc:memory_arena_reuse_free_list [SDT event]
    sdt_libc:memory_arena_reuse_wait [SDT event]
    sdt_libc:memory_calloc_retry [SDT event]
    sdt_libc:memory_heap_free [SDT event]
    ...

    But none of them work:

    Error: No permissions to read /sys/kernel/debug/tracing/events/sdt_libc/longjmp
    Hint: Try 'sudo mount -o remount,mode=755 /sys/kernel/debug/tracing'

    ...

    Error: File /sys/kernel/debug/tracing/events/sdt_libc/longjmp not found.
    Hint: Perhaps this kernel misses some CONFIG_ setting to enable this feature?.

    What kind of patches are required for SDT probes to work?

    Thanks,

    Ingo

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