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	 e8edc6e03a
			
		
	
	
		e8edc6e03a
		
	
	
	
	
		
			
			First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			138 lines
		
	
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			138 lines
		
	
	
	
		
			4.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * include/linux/writeback.h
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|  */
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| #ifndef WRITEBACK_H
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| #define WRITEBACK_H
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| 
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| #include <linux/sched.h>
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| 
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| struct backing_dev_info;
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| 
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| extern spinlock_t inode_lock;
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| extern struct list_head inode_in_use;
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| extern struct list_head inode_unused;
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| 
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| /*
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|  * Yes, writeback.h requires sched.h
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|  * No, sched.h is not included from here.
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|  */
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| static inline int task_is_pdflush(struct task_struct *task)
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| {
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| 	return task->flags & PF_FLUSHER;
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| }
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| 
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| #define current_is_pdflush()	task_is_pdflush(current)
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| 
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| /*
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|  * fs/fs-writeback.c
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|  */
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| enum writeback_sync_modes {
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| 	WB_SYNC_NONE,	/* Don't wait on anything */
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| 	WB_SYNC_ALL,	/* Wait on every mapping */
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| 	WB_SYNC_HOLD,	/* Hold the inode on sb_dirty for sys_sync() */
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| };
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| 
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| /*
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|  * A control structure which tells the writeback code what to do.  These are
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|  * always on the stack, and hence need no locking.  They are always initialised
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|  * in a manner such that unspecified fields are set to zero.
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|  */
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| struct writeback_control {
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| 	struct backing_dev_info *bdi;	/* If !NULL, only write back this
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| 					   queue */
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| 	enum writeback_sync_modes sync_mode;
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| 	unsigned long *older_than_this;	/* If !NULL, only write back inodes
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| 					   older than this */
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| 	long nr_to_write;		/* Write this many pages, and decrement
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| 					   this for each page written */
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| 	long pages_skipped;		/* Pages which were not written */
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| 
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| 	/*
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| 	 * For a_ops->writepages(): is start or end are non-zero then this is
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| 	 * a hint that the filesystem need only write out the pages inside that
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| 	 * byterange.  The byte at `end' is included in the writeout request.
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| 	 */
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| 	loff_t range_start;
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| 	loff_t range_end;
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| 
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| 	unsigned nonblocking:1;		/* Don't get stuck on request queues */
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| 	unsigned encountered_congestion:1; /* An output: a queue is full */
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| 	unsigned for_kupdate:1;		/* A kupdate writeback */
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| 	unsigned for_reclaim:1;		/* Invoked from the page allocator */
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| 	unsigned for_writepages:1;	/* This is a writepages() call */
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| 	unsigned range_cyclic:1;	/* range_start is cyclic */
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| 
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| 	void *fs_private;		/* For use by ->writepages() */
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| };
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| 
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| /*
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|  * fs/fs-writeback.c
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|  */	
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| void writeback_inodes(struct writeback_control *wbc);
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| void wake_up_inode(struct inode *inode);
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| int inode_wait(void *);
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| void sync_inodes_sb(struct super_block *, int wait);
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| void sync_inodes(int wait);
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| 
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| /* writeback.h requires fs.h; it, too, is not included from here. */
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| static inline void wait_on_inode(struct inode *inode)
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| {
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| 	might_sleep();
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| 	wait_on_bit(&inode->i_state, __I_LOCK, inode_wait,
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| 							TASK_UNINTERRUPTIBLE);
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| }
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| 
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| /*
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|  * mm/page-writeback.c
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|  */
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| int wakeup_pdflush(long nr_pages);
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| void laptop_io_completion(void);
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| void laptop_sync_completion(void);
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| void throttle_vm_writeout(gfp_t gfp_mask);
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| 
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| /* These are exported to sysctl. */
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| extern int dirty_background_ratio;
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| extern int vm_dirty_ratio;
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| extern int dirty_writeback_interval;
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| extern int dirty_expire_interval;
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| extern int block_dump;
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| extern int laptop_mode;
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| 
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| struct ctl_table;
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| struct file;
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| int dirty_writeback_centisecs_handler(struct ctl_table *, int, struct file *,
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| 				      void __user *, size_t *, loff_t *);
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| 
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| void page_writeback_init(void);
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| void balance_dirty_pages_ratelimited_nr(struct address_space *mapping,
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| 					unsigned long nr_pages_dirtied);
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| 
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| static inline void
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| balance_dirty_pages_ratelimited(struct address_space *mapping)
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| {
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| 	balance_dirty_pages_ratelimited_nr(mapping, 1);
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| }
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| 
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| typedef int (*writepage_t)(struct page *page, struct writeback_control *wbc,
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| 				void *data);
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| 
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| int pdflush_operation(void (*fn)(unsigned long), unsigned long arg0);
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| int generic_writepages(struct address_space *mapping,
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| 		       struct writeback_control *wbc);
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| int write_cache_pages(struct address_space *mapping,
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| 		      struct writeback_control *wbc, writepage_t writepage,
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| 		      void *data);
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| int do_writepages(struct address_space *mapping, struct writeback_control *wbc);
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| int sync_page_range(struct inode *inode, struct address_space *mapping,
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| 			loff_t pos, loff_t count);
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| int sync_page_range_nolock(struct inode *inode, struct address_space *mapping,
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| 			   loff_t pos, loff_t count);
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| void set_page_dirty_balance(struct page *page);
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| void writeback_set_ratelimit(void);
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| 
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| /* pdflush.c */
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| extern int nr_pdflush_threads;	/* Global so it can be exported to sysctl
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| 				   read-only. */
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| 
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| 
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| #endif		/* WRITEBACK_H */
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