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authorThomas Gleixner <tglx@linutronix.de>2020-06-30 12:07:51 +0200
committerThomas Gleixner <tglx@linutronix.de>2020-06-30 12:07:51 +0200
commit98817a84ff1c755c347ac633ff017a623a631fad (patch)
tree93bd22485a697d1dbba97b2829b82e03c08ae57f /tools/lib/api/fs
parent0e698dfa282211e414076f9dc7e83c1c288314fd (diff)
parent005c34ae4b44f085120d7f371121ec7ded677761 (diff)
Merge tag 'irqchip-fixes-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent
Pull irqchip fixes from Marc Zyngier: - Fix atomicity of affinity update in the GIC driver - Don't sleep in atomic when waiting for a GICv4.1 RD to respond - Fix a couple of typos in user-visible messages
Diffstat (limited to 'tools/lib/api/fs')
-rw-r--r--tools/lib/api/fs/fs.c17
-rw-r--r--tools/lib/api/fs/fs.h12
2 files changed, 29 insertions, 0 deletions
diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c
index 027b18f7ed8c..82f53d81a7a7 100644
--- a/tools/lib/api/fs/fs.c
+++ b/tools/lib/api/fs/fs.c
@@ -90,6 +90,7 @@ struct fs {
const char * const *mounts;
char path[PATH_MAX];
bool found;
+ bool checked;
long magic;
};
@@ -111,31 +112,37 @@ static struct fs fs__entries[] = {
.name = "sysfs",
.mounts = sysfs__fs_known_mountpoints,
.magic = SYSFS_MAGIC,
+ .checked = false,
},
[FS__PROCFS] = {
.name = "proc",
.mounts = procfs__known_mountpoints,
.magic = PROC_SUPER_MAGIC,
+ .checked = false,
},
[FS__DEBUGFS] = {
.name = "debugfs",
.mounts = debugfs__known_mountpoints,
.magic = DEBUGFS_MAGIC,
+ .checked = false,
},
[FS__TRACEFS] = {
.name = "tracefs",
.mounts = tracefs__known_mountpoints,
.magic = TRACEFS_MAGIC,
+ .checked = false,
},
[FS__HUGETLBFS] = {
.name = "hugetlbfs",
.mounts = hugetlbfs__known_mountpoints,
.magic = HUGETLBFS_MAGIC,
+ .checked = false,
},
[FS__BPF_FS] = {
.name = "bpf",
.mounts = bpf_fs__known_mountpoints,
.magic = BPF_FS_MAGIC,
+ .checked = false,
},
};
@@ -158,6 +165,7 @@ static bool fs__read_mounts(struct fs *fs)
}
fclose(fp);
+ fs->checked = true;
return fs->found = found;
}
@@ -220,6 +228,7 @@ static bool fs__env_override(struct fs *fs)
return false;
fs->found = true;
+ fs->checked = true;
strncpy(fs->path, override_path, sizeof(fs->path) - 1);
fs->path[sizeof(fs->path) - 1] = '\0';
return true;
@@ -246,6 +255,14 @@ static const char *fs__mountpoint(int idx)
if (fs->found)
return (const char *)fs->path;
+ /* the mount point was already checked for the mount point
+ * but and did not exist, so return NULL to avoid scanning again.
+ * This makes the found and not found paths cost equivalent
+ * in case of multiple calls.
+ */
+ if (fs->checked)
+ return NULL;
+
return fs__get_mountpoint(fs);
}
diff --git a/tools/lib/api/fs/fs.h b/tools/lib/api/fs/fs.h
index 936edb95e1f3..aa222ca30311 100644
--- a/tools/lib/api/fs/fs.h
+++ b/tools/lib/api/fs/fs.h
@@ -18,6 +18,18 @@
const char *name##__mount(void); \
bool name##__configured(void); \
+/*
+ * The xxxx__mountpoint() entry points find the first match mount point for each
+ * filesystems listed below, where xxxx is the filesystem type.
+ *
+ * The interface is as follows:
+ *
+ * - If a mount point is found on first call, it is cached and used for all
+ * subsequent calls.
+ *
+ * - If a mount point is not found, NULL is returned on first call and all
+ * subsequent calls.
+ */
FS(sysfs)
FS(procfs)
FS(debugfs)