diff options
Diffstat (limited to 'tools/lib/api/fs/fs.c')
| -rw-r--r-- | tools/lib/api/fs/fs.c | 165 |
1 files changed, 153 insertions, 12 deletions
diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c index 128ef6332a6b..459599d1b6c4 100644 --- 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]; |