Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[karo-tx-linux.git] / tools / lib / api / fs / fs.c

diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c
index 128ef6332a6bd89c0ddbeef283c4dfccbf5f8417..459599d1b6c410b7b41333c13f248ee685c2dd4a 100644 (file)
--- a/tools/lib/api/fs/fs.c
+++ b/tools/lib/api/fs/fs.c
@@ -1,7 +1,6 @@
-/* TODO merge/factor in debugfs.c here */
-
 #include <ctype.h>
 #include <errno.h>
+#include <limits.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -11,10 +10,29 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <sys/mount.h>
 
-#include "debugfs.h"
 #include "fs.h"
 
+#define _STR(x) #x
+#define STR(x) _STR(x)
+
+#ifndef SYSFS_MAGIC
+#define SYSFS_MAGIC            0x62656572
+#endif
+
+#ifndef PROC_SUPER_MAGIC
+#define PROC_SUPER_MAGIC       0x9fa0
+#endif
+
+#ifndef DEBUGFS_MAGIC
+#define DEBUGFS_MAGIC          0x64626720
+#endif
+
+#ifndef TRACEFS_MAGIC
+#define TRACEFS_MAGIC          0x74726163
+#endif
+
 static const char * const sysfs__fs_known_mountpoints[] = {
        "/sys",
        0,
@@ -25,19 +43,48 @@ static const char * const procfs__known_mountpoints[] = {
        0,
 };
 
+#ifndef DEBUGFS_DEFAULT_PATH
+#define DEBUGFS_DEFAULT_PATH "/sys/kernel/debug"
+#endif
+
+static const char * const debugfs__known_mountpoints[] = {
+       DEBUGFS_DEFAULT_PATH,
+       "/debug",
+       0,
+};
+
+
+#ifndef TRACEFS_DEFAULT_PATH
+#define TRACEFS_DEFAULT_PATH "/sys/kernel/tracing"
+#endif
+
+static const char * const tracefs__known_mountpoints[] = {
+       TRACEFS_DEFAULT_PATH,
+       "/sys/kernel/debug/tracing",
+       "/tracing",
+       "/trace",
+       0,
+};
+
 struct fs {
        const char              *name;
        const char * const      *mounts;
-       char                     path[PATH_MAX + 1];
+       char                     path[PATH_MAX];
        bool                     found;
        long                     magic;
 };
 
 enum {
-       FS__SYSFS  = 0,
-       FS__PROCFS = 1,
+       FS__SYSFS   = 0,
+       FS__PROCFS  = 1,
+       FS__DEBUGFS = 2,
+       FS__TRACEFS = 3,
 };
 
+#ifndef TRACEFS_MAGIC
+#define TRACEFS_MAGIC 0x74726163
+#endif
+
 static struct fs fs__entries[] = {
        [FS__SYSFS] = {
                .name   = "sysfs",
@@ -49,6 +96,16 @@ static struct fs fs__entries[] = {
                .mounts = procfs__known_mountpoints,
                .magic  = PROC_SUPER_MAGIC,
        },
+       [FS__DEBUGFS] = {
+               .name   = "debugfs",
+               .mounts = debugfs__known_mountpoints,
+               .magic  = DEBUGFS_MAGIC,
+       },
+       [FS__TRACEFS] = {
+               .name   = "tracefs",
+               .mounts = tracefs__known_mountpoints,
+               .magic  = TRACEFS_MAGIC,
+       },
 };
 
 static bool fs__read_mounts(struct fs *fs)
@@ -159,14 +216,54 @@ static const char *fs__mountpoint(int idx)
        return fs__get_mountpoint(fs);
 }
 
-#define FS__MOUNTPOINT(name, idx)      \
-const char *name##__mountpoint(void)   \
-{                                      \
-       return fs__mountpoint(idx);     \
+static const char *mount_overload(struct fs *fs)
+{
+       size_t name_len = strlen(fs->name);
+       /* "PERF_" + name + "_ENVIRONMENT" + '\0' */
+       char upper_name[5 + name_len + 12 + 1];
+
+       snprintf(upper_name, name_len, "PERF_%s_ENVIRONMENT", fs->name);
+       mem_toupper(upper_name, name_len);
+
+       return getenv(upper_name) ?: *fs->mounts;
+}
+
+static const char *fs__mount(int idx)
+{
+       struct fs *fs = &fs__entries[idx];
+       const char *mountpoint;
+
+       if (fs__mountpoint(idx))
+               return (const char *)fs->path;
+
+       mountpoint = mount_overload(fs);
+
+       if (mount(NULL, mountpoint, fs->name, 0, NULL) < 0)
+               return NULL;
+
+       return fs__check_mounts(fs) ? fs->path : NULL;
+}
+
+#define FS(name, idx)                          \
+const char *name##__mountpoint(void)           \
+{                                              \
+       return fs__mountpoint(idx);             \
+}                                              \
+                                               \
+const char *name##__mount(void)                        \
+{                                              \
+       return fs__mount(idx);                  \
+}                                              \
+                                               \
+bool name##__configured(void)                  \
+{                                              \
+       return name##__mountpoint() != NULL;    \
 }
 
-FS__MOUNTPOINT(sysfs,  FS__SYSFS);
-FS__MOUNTPOINT(procfs, FS__PROCFS);
+FS(sysfs,   FS__SYSFS);
+FS(procfs,  FS__PROCFS);
+FS(debugfs, FS__DEBUGFS);
+FS(tracefs, FS__TRACEFS);
 
 int filename__read_int(const char *filename, int *value)
 {
@@ -185,6 +282,50 @@ int filename__read_int(const char *filename, int *value)
        return err;
 }
 
+int filename__read_ull(const char *filename, unsigned long long *value)
+{
+       char line[64];
+       int fd = open(filename, O_RDONLY), err = -1;
+
+       if (fd < 0)
+               return -1;
+
+       if (read(fd, line, sizeof(line)) > 0) {
+               *value = strtoull(line, NULL, 10);
+               if (*value != ULLONG_MAX)
+                       err = 0;
+       }
+
+       close(fd);
+       return err;
+}
+
+int sysfs__read_ull(const char *entry, unsigned long long *value)
+{
+       char path[PATH_MAX];
+       const char *sysfs = sysfs__mountpoint();
+
+       if (!sysfs)
+               return -1;
+
+       snprintf(path, sizeof(path), "%s/%s", sysfs, entry);
+
+       return filename__read_ull(path, value);
+}
+
+int sysfs__read_int(const char *entry, int *value)
+{
+       char path[PATH_MAX];
+       const char *sysfs = sysfs__mountpoint();
+
+       if (!sysfs)
+               return -1;
+
+       snprintf(path, sizeof(path), "%s/%s", sysfs, entry);
+
+       return filename__read_int(path, value);
+}
+
 int sysctl__read_int(const char *sysctl, int *value)
 {
        char path[PATH_MAX];