From mboxrd@z Thu Jan 1 00:00:00 1970 From: Masami Hiramatsu Subject: [RFC PATCH 10/11] tracing: of: Add kprobe event support Date: Sat, 22 Jun 2019 01:19:40 +0900 Message-ID: <156113398039.28344.4353616217444927643.stgit@devnote2> References: <156113387975.28344.16009584175308192243.stgit@devnote2> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <156113387975.28344.16009584175308192243.stgit@devnote2> Sender: linux-kernel-owner@vger.kernel.org To: Steven Rostedt , Rob Herring , Frank Rowand , Tom Zanussi Cc: Ingo Molnar , Namhyung Kim , Jiri Olsa , Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org Add kprobe event support in event node. User can add probe definitions by "probes" property as a string array. Signed-off-by: Masami Hiramatsu --- kernel/trace/trace_kprobe.c | 5 +++ kernel/trace/trace_of.c | 65 ++++++++++++++++++++++++++++++++++++------- 2 files changed, 60 insertions(+), 10 deletions(-) diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 5166a12a9d49..cc5ba13028cd 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -765,6 +765,11 @@ static int create_or_delete_trace_kprobe(int argc, char **argv) return ret == -ECANCELED ? -EINVAL : ret; } +int trace_kprobe_run_command(const char *command) +{ + return trace_run_command(command, create_or_delete_trace_kprobe); +} + static int trace_kprobe_release(struct dyn_event *ev) { struct trace_kprobe *tk = to_trace_kprobe(ev); diff --git a/kernel/trace/trace_of.c b/kernel/trace/trace_of.c index 696f59234e62..43d87e5065a3 100644 --- a/kernel/trace/trace_of.c +++ b/kernel/trace/trace_of.c @@ -23,6 +23,7 @@ extern void __init trace_init_tracepoint_printk(void); extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr, unsigned long size, int cpu_id); extern int trigger_process_regex(struct trace_event_file *file, char *buff); +extern int trace_kprobe_run_command(const char *command); static void __init trace_of_set_ftrace_options(struct trace_array *tr, struct device_node *node) @@ -99,14 +100,47 @@ trace_of_enable_events(struct trace_array *tr, struct device_node *node) } } +static int __init +trace_of_add_kprobe_event(struct device_node *node, + const char *group, const char *event) +{ + struct property *prop; + char buf[MAX_BUF_LEN]; + const char *p; + char *q; + int len, ret; + + len = snprintf(buf, ARRAY_SIZE(buf) - 1, "p:%s/%s ", group, event); + if (len >= ARRAY_SIZE(buf)) { + pr_err("Event name is too long: %s\n", event); + return -E2BIG; + } + q = buf + len; + len = ARRAY_SIZE(buf) - len; + + of_property_for_each_string(node, "probes", prop, p) { + if (strlcpy(q, p, len) >= len) { + pr_err("Probe definition is too long: %s\n", p); + return -E2BIG; + } + ret = trace_kprobe_run_command(buf); + if (ret < 0) { + pr_err("Failed to add probe: %s\n", buf); + return ret; + } + } + + return 0; +} + static void __init trace_of_init_one_event(struct trace_array *tr, struct device_node *node) { struct trace_event_file *file; struct property *prop; char buf[MAX_BUF_LEN]; - char *bufp; - const char *p; + const char *p, *group; + char *event; int err; if (!of_node_name_prefix(node, "event")) @@ -123,18 +157,29 @@ trace_of_init_one_event(struct trace_array *tr, struct device_node *node) pr_err("Event name is too long: %s\n", p); return; } - bufp = buf; - - p = strsep(&bufp, ":"); - if (!bufp) { - pr_err("%s has no group name\n", buf); - return; + event = buf; + + group = strsep(&event, ":"); + /* For a kprobe event, we have to generates an event at first */ + if (of_find_property(node, "probes", NULL)) { + if (!event) { + event = buf; + group = "kprobes"; + } + err = trace_of_add_kprobe_event(node, group, event); + if (err < 0) + return; + } else { + if (!event) { + pr_err("%s has no group name\n", buf); + return; + } } mutex_lock(&event_mutex); - file = find_event_file(tr, buf, bufp); + file = find_event_file(tr, group, event); if (!file) { - pr_err("Failed to find event: %s\n", buf); + pr_err("Failed to find event: %s:%s\n", group, event); return; }