From a1d9972e59e15538458c030affbfc298c32a47f8 Mon Sep 17 00:00:00 2001 From: Ravi Bangoria Date: Tue, 4 Oct 2016 15:57:45 +0530 Subject: [PATCH] perf uretprobe ppc64le: Fix probe location Perf uretprobe probes on GEP(Global Entry Point) which fails to record all function calls via LEP(Local Entry Point). Fix that by probing on LEP. Objdump: 00000000100005f0 : 100005f0: 02 10 40 3c lis r2,4098 100005f4: 00 7f 42 38 addi r2,r2,32512 100005f8: a6 02 08 7c mflr r0 100005fc: 10 00 01 f8 std r0,16(r1) 10000600: f8 ff e1 fb std r31,-8(r1) Before applying patch: $ cat /sys/kernel/debug/tracing/uprobe_events r:probe_uprobe_test/doit /home/ravi/uprobe_test:0x00000000000005f0 After applying patch: $ cat /sys/kernel/debug/tracing/uprobe_events r:probe_uprobe_test/doit /home/ravi/uprobe_test:0x00000000000005f8 This is not the case with kretprobes because the kernel itself finds LEP and probes on it. Signed-off-by: Ravi Bangoria Cc: Alexander Shishkin Cc: Balbir Singh Cc: Masami Hiramatsu Cc: Naveen N. Rao Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1475576865-6562-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/powerpc/util/sym-handling.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c index ed9d5d15d5b6..1030a6e504bb 100644 --- a/tools/perf/arch/powerpc/util/sym-handling.c +++ b/tools/perf/arch/powerpc/util/sym-handling.c @@ -82,7 +82,8 @@ void arch__fix_tev_from_maps(struct perf_probe_event *pev, * * In addition, we shouldn't specify an offset for kretprobes. */ - if (pev->point.offset || pev->point.retprobe || !map || !sym) + if (pev->point.offset || (!pev->uprobes && pev->point.retprobe) || + !map || !sym) return; lep_offset = PPC64_LOCAL_ENTRY_OFFSET(sym->arch_sym); -- 2.20.1