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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /tools/lib/api/fs/tracing_path.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/lib/api/fs/tracing_path.c')
-rw-r--r--tools/lib/api/fs/tracing_path.c167
1 files changed, 167 insertions, 0 deletions
diff --git a/tools/lib/api/fs/tracing_path.c b/tools/lib/api/fs/tracing_path.c
new file mode 100644
index 000000000..5afb11b30
--- /dev/null
+++ b/tools/lib/api/fs/tracing_path.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef _GNU_SOURCE
+# define _GNU_SOURCE
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <linux/string.h>
+#include <errno.h>
+#include <unistd.h>
+#include "fs.h"
+
+#include "tracing_path.h"
+
+static char tracing_mnt[PATH_MAX] = "/sys/kernel/debug";
+static char tracing_path[PATH_MAX] = "/sys/kernel/debug/tracing";
+static char tracing_events_path[PATH_MAX] = "/sys/kernel/debug/tracing/events";
+
+static void __tracing_path_set(const char *tracing, const char *mountpoint)
+{
+ snprintf(tracing_mnt, sizeof(tracing_mnt), "%s", mountpoint);
+ snprintf(tracing_path, sizeof(tracing_path), "%s/%s",
+ mountpoint, tracing);
+ snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s",
+ mountpoint, tracing, "events");
+}
+
+static const char *tracing_path_tracefs_mount(void)
+{
+ const char *mnt;
+
+ mnt = tracefs__mount();
+ if (!mnt)
+ return NULL;
+
+ __tracing_path_set("", mnt);
+
+ return tracing_path;
+}
+
+static const char *tracing_path_debugfs_mount(void)
+{
+ const char *mnt;
+
+ mnt = debugfs__mount();
+ if (!mnt)
+ return NULL;
+
+ __tracing_path_set("tracing/", mnt);
+
+ return tracing_path;
+}
+
+const char *tracing_path_mount(void)
+{
+ const char *mnt;
+
+ mnt = tracing_path_tracefs_mount();
+ if (mnt)
+ return mnt;
+
+ mnt = tracing_path_debugfs_mount();
+
+ return mnt;
+}
+
+void tracing_path_set(const char *mntpt)
+{
+ __tracing_path_set("tracing/", mntpt);
+}
+
+char *get_tracing_file(const char *name)
+{
+ char *file;
+
+ if (asprintf(&file, "%s/%s", tracing_path_mount(), name) < 0)
+ return NULL;
+
+ return file;
+}
+
+void put_tracing_file(char *file)
+{
+ free(file);
+}
+
+char *get_events_file(const char *name)
+{
+ char *file;
+
+ if (asprintf(&file, "%s/events/%s", tracing_path_mount(), name) < 0)
+ return NULL;
+
+ return file;
+}
+
+void put_events_file(char *file)
+{
+ free(file);
+}
+
+DIR *tracing_events__opendir(void)
+{
+ DIR *dir = NULL;
+ char *path = get_tracing_file("events");
+
+ if (path) {
+ dir = opendir(path);
+ put_events_file(path);
+ }
+
+ return dir;
+}
+
+int tracing_path__strerror_open_tp(int err, char *buf, size_t size,
+ const char *sys, const char *name)
+{
+ char sbuf[128];
+ char filename[PATH_MAX];
+
+ snprintf(filename, PATH_MAX, "%s/%s", sys, name ?: "*");
+
+ switch (err) {
+ case ENOENT:
+ /*
+ * We will get here if we can't find the tracepoint, but one of
+ * debugfs or tracefs is configured, which means you probably
+ * want some tracepoint which wasn't compiled in your kernel.
+ * - jirka
+ */
+ if (debugfs__configured() || tracefs__configured()) {
+ /* sdt markers */
+ if (!strncmp(filename, "sdt_", 4)) {
+ snprintf(buf, size,
+ "Error:\tFile %s/%s not found.\n"
+ "Hint:\tSDT event cannot be directly recorded on.\n"
+ "\tPlease first use 'perf probe %s:%s' before recording it.\n",
+ tracing_events_path, filename, sys, name);
+ } else {
+ snprintf(buf, size,
+ "Error:\tFile %s/%s not found.\n"
+ "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n",
+ tracing_events_path, filename);
+ }
+ break;
+ }
+ snprintf(buf, size, "%s",
+ "Error:\tUnable to find debugfs/tracefs\n"
+ "Hint:\tWas your kernel compiled with debugfs/tracefs support?\n"
+ "Hint:\tIs the debugfs/tracefs filesystem mounted?\n"
+ "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'");
+ break;
+ case EACCES: {
+ snprintf(buf, size,
+ "Error:\tNo permissions to read %s/%s\n"
+ "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n",
+ tracing_events_path, filename, tracing_path_mount());
+ }
+ break;
+ default:
+ snprintf(buf, size, "%s", str_error_r(err, sbuf, sizeof(sbuf)));
+ break;
+ }
+
+ return 0;
+}