• Ravi Bangoria's avatar
    perf probe: Change MAX_CMDLEN · 2e1f8f78
    Ravi Bangoria authored
    There are many SDT markers in powerpc whose uprobe definition goes
    beyond current MAX_CMDLEN, especially when target filename is long and
    sdt marker has long list of arguments. For example, definition of sdt
    marker
    
      method__compile__end: 8@17 8@9 8@10 -4@8 8@7 -4@6 8@5 -4@4 1@37(28)
    
    from file
    
      /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.91-2.b14.fc22.ppc64/jre/lib/ppc64/server/libjvm.so
    
    is
    
      p:sdt_hotspot/method__compile__end /usr/lib/jvm/java-1.8.0-openjdk-\
        1.8.0.91-2.b14.fc22.ppc64/jre/lib/ppc64/server/libjvm.so:0x4c4e00\
        arg1=%gpr17:u64 arg2=%gpr9:u64 arg3=%gpr10:u64 arg4=%gpr8:s32\
        arg5=%gpr7:u64 arg6=%gpr6:s32 arg7=%gpr5:u64 arg8=%gpr4:s32\
        arg9=+37(%gpr28):u8
    
    'perf probe' fails with segfault for such markers. As the uprobe_events
    file accepts definitions up to 4094 characters(4096 - 2 (\n\0)),
    increase value of MAX_CMDLEN match that.
    Signed-off-by: default avatarRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
    Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
    Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
    Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
    Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
    Cc: Michael Ellerman <mpe@ellerman.id.au>
    Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Link: http://lkml.kernel.org/r/20170207054547.3690-1-ravi.bangoria@linux.vnet.ibm.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
    2e1f8f78
probe-file.c 20.2 KB