From: Masami Hiramatsu <mhiramat@xxxxxxxxxx> [ Upstream commit dee36a2abb67c175265d49b9a8c7dfa564463d9a ] Since debuginfo__find_probes() callback function can be called with the location which already passed, the callback function must filter out such overlapped locations. add_probe_trace_event() has already done it by commit 1a375ae7659a ("perf probe: Skip same probe address for a given line"), but add_available_vars() doesn't. Thus perf probe -v shows same address repeatedly as below: # perf probe -V vfs_read:18 Available variables at vfs_read:18 @<vfs_read+217> char* buf loff_t* pos ssize_t ret struct file* file @<vfs_read+217> char* buf loff_t* pos ssize_t ret struct file* file @<vfs_read+226> char* buf loff_t* pos ssize_t ret struct file* file With this fix, perf probe -V shows it correctly: # perf probe -V vfs_read:18 Available variables at vfs_read:18 @<vfs_read+217> char* buf loff_t* pos ssize_t ret struct file* file @<vfs_read+226> char* buf loff_t* pos ssize_t ret struct file* file Fixes: cf6eb489e5c0 ("perf probe: Show accessible local variables") Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Link: http://lore.kernel.org/lkml/157241938927.32002.4026859017790562751.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/perf/util/probe-finder.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index 28a0f37b05c0..d917f83e8e85 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -1331,6 +1331,18 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data) return DIE_FIND_CB_SIBLING; } +static bool available_var_finder_overlap(struct available_var_finder *af) +{ + int i; + + for (i = 0; i < af->nvls; i++) { + if (af->pf.addr == af->vls[i].point.address) + return true; + } + return false; + +} + /* Add a found vars into available variables list */ static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf) { @@ -1341,6 +1353,14 @@ static int add_available_vars(Dwarf_Die *sc_die, struct probe_finder *pf) Dwarf_Die die_mem; int ret; + /* + * For some reason (e.g. different column assigned to same address), + * this callback can be called with the address which already passed. + * Ignore it first. + */ + if (available_var_finder_overlap(af)) + return 0; + /* Check number of tevs */ if (af->nvls == af->max_vls) { pr_warning("Too many( > %d) probe point found.\n", af->max_vls); -- 2.20.1