From e63cc2397ecc0f2b604f22fb9cdbb05911c1e5d4 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Fri, 16 Oct 2009 20:07:28 -0400 Subject: [PATCH] tracing/kprobes: Add failure messages for debugging Add verbose failure messages to kprobe-tracer for debugging. Signed-off-by: Masami Hiramatsu Cc: Frederic Weisbecker Cc: Arnaldo Carvalho de Melo Cc: Steven Rostedt Cc: Paul Mackerras Cc: Peter Zijlstra LKML-Reference: <20091017000728.16556.16713.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar --- kernel/trace/trace_kprobe.c | 35 +++++++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 8 deletions(-) diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index cdacdab10020..b8ef707c84d7 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -597,15 +597,19 @@ static int create_trace_probe(int argc, char **argv) void *addr = NULL; char buf[MAX_EVENT_NAME_LEN]; - if (argc < 2) + if (argc < 2) { + pr_info("Probe point is not specified.\n"); return -EINVAL; + } if (argv[0][0] == 'p') is_return = 0; else if (argv[0][0] == 'r') is_return = 1; - else + else { + pr_info("Probe definition must be started with 'p' or 'r'.\n"); return -EINVAL; + } if (argv[0][1] == ':') { event = &argv[0][2]; @@ -625,21 +629,29 @@ static int create_trace_probe(int argc, char **argv) } if (isdigit(argv[1][0])) { - if (is_return) + if (is_return) { + pr_info("Return probe point must be a symbol.\n"); return -EINVAL; + } /* an address specified */ ret = strict_strtoul(&argv[0][2], 0, (unsigned long *)&addr); - if (ret) + if (ret) { + pr_info("Failed to parse address.\n"); return ret; + } } else { /* a symbol specified */ symbol = argv[1]; /* TODO: support .init module functions */ ret = split_symbol_offset(symbol, &offset); - if (ret) + if (ret) { + pr_info("Failed to parse symbol.\n"); return ret; - if (offset && is_return) + } + if (offset && is_return) { + pr_info("Return probe must be used without offset.\n"); return -EINVAL; + } } argc -= 2; argv += 2; @@ -658,8 +670,11 @@ static int create_trace_probe(int argc, char **argv) } tp = alloc_trace_probe(group, event, addr, symbol, offset, argc, is_return); - if (IS_ERR(tp)) + if (IS_ERR(tp)) { + pr_info("Failed to allocate trace_probe.(%d)\n", + (int)PTR_ERR(tp)); return PTR_ERR(tp); + } /* parse arguments */ ret = 0; @@ -672,6 +687,8 @@ static int create_trace_probe(int argc, char **argv) arg = argv[i]; if (conflict_field_name(argv[i], tp->args, i)) { + pr_info("Argument%d name '%s' conflicts with " + "another field.\n", i, argv[i]); ret = -EINVAL; goto error; } @@ -685,8 +702,10 @@ static int create_trace_probe(int argc, char **argv) goto error; } ret = parse_probe_arg(arg, &tp->args[i].fetch, is_return); - if (ret) + if (ret) { + pr_info("Parse error at argument%d. (%d)\n", i, ret); goto error; + } } tp->nr_args = i;