fs: remove fget_many and fput_many interface

These two interface were added in 091141a42 commit,
but now there is no place to call them.

The only user of fput/fget_many() was removed in commit
62906e89e63b ("io_uring: remove file batch-get optimisation").

A user of get_file_rcu_many() were removed in commit
f073531070d2 ("init: add an init_dup helper").

And replace atomic_long_sub/add to atomic_long_dec/inc
can improve performance.

Here are the test results of unixbench:

Cmd: ./Run -c 64 context1

Without patch:
System Benchmarks Partial Index              BASELINE       RESULT    INDEX
Pipe-based Context Switching                   4000.0    2798407.0   6996.0
                                                                   ========
System Benchmarks Index Score (Partial Only)                         6996.0

With patch:
System Benchmarks Partial Index              BASELINE       RESULT    INDEX
Pipe-based Context Switching                   4000.0    3486268.8   8715.7
                                                                   ========
System Benchmarks Index Score (Partial Only)                         8715.7

Signed-off-by: Gou Hao <gouhao@uniontech.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/file.c b/fs/file.c
index ee931734670257393aa9ee1383596e233c69d05b..4c59f410a48df936d28ff5e33c19b14555c986f5 100644 (file)
--- a/fs/file.c
+++ b/fs/file.c
@@ -871,7 +871,7 @@ void do_close_on_exec(struct files_struct *files)
 }
 
 static inline struct file *__fget_files_rcu(struct files_struct *files,
-       unsigned int fd, fmode_t mask, unsigned int refs)
+       unsigned int fd, fmode_t mask)
 {
        for (;;) {
                struct file *file;
@@ -897,10 +897,9 @@ static inline struct file *__fget_files_rcu(struct files_struct *files,
                 * Such a race can take two forms:
                 *
                 *  (a) the file ref already went down to zero,
-                *      and get_file_rcu_many() fails. Just try
-                *      again:
+                *      and get_file_rcu() fails. Just try again:
                 */
-               if (unlikely(!get_file_rcu_many(file, refs)))
+               if (unlikely(!get_file_rcu(file)))
                        continue;
 
                /*
@@ -909,11 +908,11 @@ static inline struct file *__fget_files_rcu(struct files_struct *files,
                 *       pointer having changed, because it always goes
                 *       hand-in-hand with 'fdt'.
                 *
-                * If so, we need to put our refs and try again.
+                * If so, we need to put our ref and try again.
                 */
                if (unlikely(rcu_dereference_raw(files->fdt) != fdt) ||
                    unlikely(rcu_dereference_raw(*fdentry) != file)) {
-                       fput_many(file, refs);
+                       fput(file);
                        continue;
                }
 
@@ -926,37 +925,31 @@ static inline struct file *__fget_files_rcu(struct files_struct *files,
 }
 
 static struct file *__fget_files(struct files_struct *files, unsigned int fd,
-                                fmode_t mask, unsigned int refs)
+                                fmode_t mask)
 {
        struct file *file;
 
        rcu_read_lock();
-       file = __fget_files_rcu(files, fd, mask, refs);
+       file = __fget_files_rcu(files, fd, mask);
        rcu_read_unlock();
 
        return file;
 }
 
-static inline struct file *__fget(unsigned int fd, fmode_t mask,
-                                 unsigned int refs)
-{
-       return __fget_files(current->files, fd, mask, refs);
-}
-
-struct file *fget_many(unsigned int fd, unsigned int refs)
+static inline struct file *__fget(unsigned int fd, fmode_t mask)
 {
-       return __fget(fd, FMODE_PATH, refs);
+       return __fget_files(current->files, fd, mask);
 }
 
 struct file *fget(unsigned int fd)
 {
-       return __fget(fd, FMODE_PATH, 1);
+       return __fget(fd, FMODE_PATH);
 }
 EXPORT_SYMBOL(fget);
 
 struct file *fget_raw(unsigned int fd)
 {
-       return __fget(fd, 0, 1);
+       return __fget(fd, 0);
 }
 EXPORT_SYMBOL(fget_raw);
 
@@ -966,7 +959,7 @@ struct file *fget_task(struct task_struct *task, unsigned int fd)
 
        task_lock(task);
        if (task->files)
-               file = __fget_files(task->files, fd, 0, 1);
+               file = __fget_files(task->files, fd, 0);
        task_unlock(task);
 
        return file;
@@ -1035,7 +1028,7 @@ static unsigned long __fget_light(unsigned int fd, fmode_t mask)
                        return 0;
                return (unsigned long)file;
        } else {
-               file = __fget(fd, mask, 1);
+               file = __fget(fd, mask);
                if (!file)
                        return 0;
                return FDPUT_FPUT | (unsigned long)file;

diff --git a/fs/file_table.c b/fs/file_table.c
index 7d2e692b66a94fcfc609747802517e27489b8a0c..1ffd74bbbed69cd246a6e7f7811afd0e96fd5c50 100644 (file)
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -368,9 +368,9 @@ EXPORT_SYMBOL_GPL(flush_delayed_fput);
 
 static DECLARE_DELAYED_WORK(delayed_fput_work, delayed_fput);
 
-void fput_many(struct file *file, unsigned int refs)
+void fput(struct file *file)
 {
-       if (atomic_long_sub_and_test(refs, &file->f_count)) {
+       if (atomic_long_dec_and_test(&file->f_count)) {
                struct task_struct *task = current;
 
                if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) {
@@ -389,11 +389,6 @@ void fput_many(struct file *file, unsigned int refs)
        }
 }
 
-void fput(struct file *file)
-{
-       fput_many(file, 1);
-}
-
 /*
  * synchronous analog of fput(); for kernel threads that might be needed
  * in some umount() (and thus can't use flush_delayed_fput() without

diff --git a/include/linux/file.h b/include/linux/file.h
index 51e830b4fe3ab19764f7a5d385550907dbd765cb..39704eae83e27fdc8b099de6718f5f1392f4904c 100644 (file)
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -14,7 +14,6 @@
 struct file;
 
 extern void fput(struct file *);
-extern void fput_many(struct file *, unsigned int);
 
 struct file_operations;
 struct task_struct;
@@ -47,7 +46,6 @@ static inline void fdput(struct fd fd)
 }
 
 extern struct file *fget(unsigned int fd);
-extern struct file *fget_many(unsigned int fd, unsigned int refs);
 extern struct file *fget_raw(unsigned int fd);
 extern struct file *fget_task(struct task_struct *task, unsigned int fd);
 extern unsigned long __fdget(unsigned int fd);

diff --git a/include/linux/fs.h b/include/linux/fs.h
index bbde95387a23af8daf91f0926069a2090c35bd0f..3660c338bb16eb24e97a21ccf0ad665422adf814 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -981,9 +981,7 @@ static inline struct file *get_file(struct file *f)
        atomic_long_inc(&f->f_count);
        return f;
 }
-#define get_file_rcu_many(x, cnt)      \
-       atomic_long_add_unless(&(x)->f_count, (cnt), 0)
-#define get_file_rcu(x) get_file_rcu_many((x), 1)
+#define get_file_rcu(x) atomic_long_inc_not_zero(&(x)->f_count)
 #define file_count(x)  atomic_long_read(&(x)->f_count)
 
 #define        MAX_NON_LFS     ((1UL<<31) - 1)