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 seg fault for such markers. As uprobe_events file accepts definition upto 4094 characters(4096 - 2 (\n\0)), increase value of MAX_CMDLEN to 4094. Signed-off-by: Ravi Bangoria <ravi.bango...@linux.vnet.ibm.com> --- Changes in v2: - Set MAX_CMDLEN to 4094 instead of 512 tools/perf/util/probe-event.c | 1 - tools/perf/util/probe-file.c | 3 ++- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 6a6f44d..e6e3244 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -47,7 +47,6 @@ #include "probe-file.h" #include "session.h" -#define MAX_CMDLEN 256 #define PERFPROBE_GROUP "probe" bool probe_event_dry_run; /* Dry run flag */ diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c index 38eca3c..fdabe7e 100644 --- a/tools/perf/util/probe-file.c +++ b/tools/perf/util/probe-file.c @@ -29,7 +29,8 @@ #include "session.h" #include "perf_regs.h" -#define MAX_CMDLEN 256 +/* 4096 - 2 ('\n' + '\0') */ +#define MAX_CMDLEN 4094 static void print_open_warning(int err, bool uprobe) { -- 2.9.3