perf probe: Move ftrace probe-event operations to probe-file.c

Move ftrace probe-event operations to probe-file.c from probe-event.c.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Hemant Kumar <hemant@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20150715091407.8915.14316.stgit@localhost.localdomain
[ Fixed up strlist__new() calls wrt 4a77e2183fc0 ("perf strlist: Make dupstr be the...") ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 301 insertions, 0 deletions

diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
new file mode 100644
index 000000000000..bbb243717ec8
--- /dev/null
+++ b/tools/perf/util/probe-file.c
@@ -0,0 +1,301 @@
+/*
+ * probe-file.c : operate ftrace k/uprobe events files
+ *
+ * Written by Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include "util.h"
+#include "event.h"
+#include "strlist.h"
+#include "debug.h"
+#include "cache.h"
+#include "color.h"
+#include "symbol.h"
+#include "thread.h"
+#include <api/fs/debugfs.h>
+#include <api/fs/tracefs.h>
+#include "probe-event.h"
+#include "probe-file.h"
+#include "session.h"
+
+#define MAX_CMDLEN 256
+
+static void print_open_warning(int err, bool uprobe)
+{
+        char sbuf[STRERR_BUFSIZE];
+
+        if (err == -ENOENT) {
+                const char *config;
+
+                if (uprobe)
+                        config = "CONFIG_UPROBE_EVENTS";
+                else
+                        config = "CONFIG_KPROBE_EVENTS";
+
+                pr_warning("%cprobe_events file does not exist"
+                           " - please rebuild kernel with %s.\n",
+                           uprobe ? 'u' : 'k', config);
+        } else if (err == -ENOTSUP)
+                pr_warning("Tracefs or debugfs is not mounted.\n");
+        else
+                pr_warning("Failed to open %cprobe_events: %s\n",
+                           uprobe ? 'u' : 'k',
+                           strerror_r(-err, sbuf, sizeof(sbuf)));
+}
+
+static void print_both_open_warning(int kerr, int uerr)
+{
+        /* Both kprobes and uprobes are disabled, warn it. */
+        if (kerr == -ENOTSUP && uerr == -ENOTSUP)
+                pr_warning("Tracefs or debugfs is not mounted.\n");
+        else if (kerr == -ENOENT && uerr == -ENOENT)
+                pr_warning("Please rebuild kernel with CONFIG_KPROBE_EVENTS "
+                           "or/and CONFIG_UPROBE_EVENTS.\n");
+        else {
+                char sbuf[STRERR_BUFSIZE];
+                pr_warning("Failed to open kprobe events: %s.\n",
+                           strerror_r(-kerr, sbuf, sizeof(sbuf)));
+                pr_warning("Failed to open uprobe events: %s.\n",
+                           strerror_r(-uerr, sbuf, sizeof(sbuf)));
+        }
+}
+
+static int open_probe_events(const char *trace_file, bool readwrite)
+{
+        char buf[PATH_MAX];
+        const char *__debugfs;
+        const char *tracing_dir = "";
+        int ret;
+
+        __debugfs = tracefs_find_mountpoint();
+        if (__debugfs == NULL) {
+                tracing_dir = "tracing/";
+
+                __debugfs = debugfs_find_mountpoint();
+                if (__debugfs == NULL)
+                        return -ENOTSUP;
+        }
+
+        ret = e_snprintf(buf, PATH_MAX, "%s/%s%s",
+                         __debugfs, tracing_dir, trace_file);
+        if (ret >= 0) {
+                pr_debug("Opening %s write=%d\n", buf, readwrite);
+                if (readwrite && !probe_event_dry_run)
+                        ret = open(buf, O_RDWR | O_APPEND, 0);
+                else
+                        ret = open(buf, O_RDONLY, 0);
+
+                if (ret < 0)
+                        ret = -errno;
+        }
+        return ret;
+}
+
+static int open_kprobe_events(bool readwrite)
+{
+        return open_probe_events("kprobe_events", readwrite);
+}
+
+static int open_uprobe_events(bool readwrite)
+{
+        return open_probe_events("uprobe_events", readwrite);
+}
+
+int probe_file__open(int flag)
+{
+        int fd;
+
+        if (flag & PF_FL_UPROBE)
+                fd = open_uprobe_events(flag & PF_FL_RW);
+        else
+                fd = open_kprobe_events(flag & PF_FL_RW);
+        if (fd < 0)
+                print_open_warning(fd, flag & PF_FL_UPROBE);
+
+        return fd;
+}
+
+int probe_file__open_both(int *kfd, int *ufd, int flag)
+{
+        if (!kfd || !ufd)
+                return -EINVAL;
+
+        *kfd = open_kprobe_events(flag & PF_FL_RW);
+        *ufd = open_uprobe_events(flag & PF_FL_RW);
+        if (*kfd < 0 && *ufd < 0) {
+                print_both_open_warning(*kfd, *ufd);
+                return *kfd;
+        }
+
+        return 0;
+}
+
+/* Get raw string list of current kprobe_events  or uprobe_events */
+struct strlist *probe_file__get_rawlist(int fd)
+{
+        int ret, idx;
+        FILE *fp;
+        char buf[MAX_CMDLEN];
+        char *p;
+        struct strlist *sl;
+
+        sl = strlist__new(NULL, NULL);
+
+        fp = fdopen(dup(fd), "r");
+        while (!feof(fp)) {
+                p = fgets(buf, MAX_CMDLEN, fp);
+                if (!p)
+                        break;
+
+                idx = strlen(p) - 1;
+                if (p[idx] == '\n')
+                        p[idx] = '\0';
+                ret = strlist__add(sl, buf);
+                if (ret < 0) {
+                        pr_debug("strlist__add failed (%d)\n", ret);
+                        strlist__delete(sl);
+                        return NULL;
+                }
+        }
+        fclose(fp);
+
+        return sl;
+}
+
+static struct strlist *__probe_file__get_namelist(int fd, bool include_group)
+{
+        char buf[128];
+        struct strlist *sl, *rawlist;
+        struct str_node *ent;
+        struct probe_trace_event tev;
+        int ret = 0;
+
+        memset(&tev, 0, sizeof(tev));
+        rawlist = probe_file__get_rawlist(fd);
+        if (!rawlist)
+                return NULL;
+        sl = strlist__new(NULL, NULL);
+        strlist__for_each(ent, rawlist) {
+                ret = parse_probe_trace_command(ent->s, &tev);
+                if (ret < 0)
+                        break;
+                if (include_group) {
+                        ret = e_snprintf(buf, 128, "%s:%s", tev.group,
+                                        tev.event);
+                        if (ret >= 0)
+                                ret = strlist__add(sl, buf);
+                } else
+                        ret = strlist__add(sl, tev.event);
+                clear_probe_trace_event(&tev);
+                if (ret < 0)
+                        break;
+        }
+        strlist__delete(rawlist);
+
+        if (ret < 0) {
+                strlist__delete(sl);
+                return NULL;
+        }
+        return sl;
+}
+
+/* Get current perf-probe event names */
+struct strlist *probe_file__get_namelist(int fd)
+{
+        return __probe_file__get_namelist(fd, false);
+}
+
+int probe_file__add_event(int fd, struct probe_trace_event *tev)
+{
+        int ret = 0;
+        char *buf = synthesize_probe_trace_command(tev);
+        char sbuf[STRERR_BUFSIZE];
+
+        if (!buf) {
+                pr_debug("Failed to synthesize probe trace event.\n");
+                return -EINVAL;
+        }
+
+        pr_debug("Writing event: %s\n", buf);
+        if (!probe_event_dry_run) {
+                ret = write(fd, buf, strlen(buf));
+                if (ret <= 0) {
+                        ret = -errno;
+                        pr_warning("Failed to write event: %s\n",
+                                   strerror_r(errno, sbuf, sizeof(sbuf)));
+                }
+        }
+        free(buf);
+
+        return ret;
+}
+
+static int __del_trace_probe_event(int fd, struct str_node *ent)
+{
+        char *p;
+        char buf[128];
+        int ret;
+
+        /* Convert from perf-probe event to trace-probe event */
+        ret = e_snprintf(buf, 128, "-:%s", ent->s);
+        if (ret < 0)
+                goto error;
+
+        p = strchr(buf + 2, ':');
+        if (!p) {
+                pr_debug("Internal error: %s should have ':' but not.\n",
+                         ent->s);
+                ret = -ENOTSUP;
+                goto error;
+        }
+        *p = '/';
+
+        pr_debug("Writing event: %s\n", buf);
+        ret = write(fd, buf, strlen(buf));
+        if (ret < 0) {
+                ret = -errno;
+                goto error;
+        }
+
+        pr_info("Removed event: %s\n", ent->s);
+        return 0;
+error:
+        pr_warning("Failed to delete event: %s\n",
+                   strerror_r(-ret, buf, sizeof(buf)));
+        return ret;
+}
+
+int probe_file__del_events(int fd, struct strfilter *filter)
+{
+        struct strlist *namelist;
+        struct str_node *ent;
+        const char *p;
+        int ret = -ENOENT;
+
+        namelist = __probe_file__get_namelist(fd, true);
+        if (!namelist)
+                return -ENOENT;
+
+        strlist__for_each(ent, namelist) {
+                p = strchr(ent->s, ':');
+                if ((p && strfilter__compare(filter, p + 1)) ||
+                    strfilter__compare(filter, ent->s)) {
+                        ret = __del_trace_probe_event(fd, ent);
+                        if (ret < 0)
+                                break;
+                }
+        }
+        strlist__delete(namelist);
+
+        return ret;
+}