From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/include/linux/backing-dev.h | 321 +++++++++++++++++++++++++++++++++++++ 1 file changed, 321 insertions(+) create mode 100644 kernel/include/linux/backing-dev.h (limited to 'kernel/include/linux/backing-dev.h') diff --git a/kernel/include/linux/backing-dev.h b/kernel/include/linux/backing-dev.h new file mode 100644 index 000000000..d87d8eced --- /dev/null +++ b/kernel/include/linux/backing-dev.h @@ -0,0 +1,321 @@ +/* + * include/linux/backing-dev.h + * + * low-level device information and state which is propagated up through + * to high-level code. + */ + +#ifndef _LINUX_BACKING_DEV_H +#define _LINUX_BACKING_DEV_H + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct page; +struct device; +struct dentry; + +/* + * Bits in backing_dev_info.state + */ +enum bdi_state { + BDI_async_congested, /* The async (write) queue is getting full */ + BDI_sync_congested, /* The sync queue is getting full */ + BDI_registered, /* bdi_register() was done */ + BDI_writeback_running, /* Writeback is in progress */ +}; + +typedef int (congested_fn)(void *, int); + +enum bdi_stat_item { + BDI_RECLAIMABLE, + BDI_WRITEBACK, + BDI_DIRTIED, + BDI_WRITTEN, + NR_BDI_STAT_ITEMS +}; + +#define BDI_STAT_BATCH (8*(1+ilog2(nr_cpu_ids))) + +struct bdi_writeback { + struct backing_dev_info *bdi; /* our parent bdi */ + + unsigned long last_old_flush; /* last old data flush */ + + struct delayed_work dwork; /* work item used for writeback */ + struct list_head b_dirty; /* dirty inodes */ + struct list_head b_io; /* parked for writeback */ + struct list_head b_more_io; /* parked for more writeback */ + struct list_head b_dirty_time; /* time stamps are dirty */ + spinlock_t list_lock; /* protects the b_* lists */ +}; + +struct backing_dev_info { + struct list_head bdi_list; + unsigned long ra_pages; /* max readahead in PAGE_CACHE_SIZE units */ + unsigned long state; /* Always use atomic bitops on this */ + unsigned int capabilities; /* Device capabilities */ + congested_fn *congested_fn; /* Function pointer if device is md/dm */ + void *congested_data; /* Pointer to aux data for congested func */ + + char *name; + + struct percpu_counter bdi_stat[NR_BDI_STAT_ITEMS]; + + unsigned long bw_time_stamp; /* last time write bw is updated */ + unsigned long dirtied_stamp; + unsigned long written_stamp; /* pages written at bw_time_stamp */ + unsigned long write_bandwidth; /* the estimated write bandwidth */ + unsigned long avg_write_bandwidth; /* further smoothed write bw */ + + /* + * The base dirty throttle rate, re-calculated on every 200ms. + * All the bdi tasks' dirty rate will be curbed under it. + * @dirty_ratelimit tracks the estimated @balanced_dirty_ratelimit + * in small steps and is much more smooth/stable than the latter. + */ + unsigned long dirty_ratelimit; + unsigned long balanced_dirty_ratelimit; + + struct fprop_local_percpu completions; + int dirty_exceeded; + + unsigned int min_ratio; + unsigned int max_ratio, max_prop_frac; + + struct bdi_writeback wb; /* default writeback info for this bdi */ + spinlock_t wb_lock; /* protects work_list & wb.dwork scheduling */ + + struct list_head work_list; + + struct device *dev; + + struct timer_list laptop_mode_wb_timer; + +#ifdef CONFIG_DEBUG_FS + struct dentry *debug_dir; + struct dentry *debug_stats; +#endif +}; + +struct backing_dev_info *inode_to_bdi(struct inode *inode); + +int __must_check bdi_init(struct backing_dev_info *bdi); +void bdi_destroy(struct backing_dev_info *bdi); + +__printf(3, 4) +int bdi_register(struct backing_dev_info *bdi, struct device *parent, + const char *fmt, ...); +int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev); +int __must_check bdi_setup_and_register(struct backing_dev_info *, char *); +void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages, + enum wb_reason reason); +void bdi_start_background_writeback(struct backing_dev_info *bdi); +void bdi_writeback_workfn(struct work_struct *work); +int bdi_has_dirty_io(struct backing_dev_info *bdi); +void bdi_wakeup_thread_delayed(struct backing_dev_info *bdi); + +extern spinlock_t bdi_lock; +extern struct list_head bdi_list; + +extern struct workqueue_struct *bdi_wq; + +static inline int wb_has_dirty_io(struct bdi_writeback *wb) +{ + return !list_empty(&wb->b_dirty) || + !list_empty(&wb->b_io) || + !list_empty(&wb->b_more_io); +} + +static inline void __add_bdi_stat(struct backing_dev_info *bdi, + enum bdi_stat_item item, s64 amount) +{ + __percpu_counter_add(&bdi->bdi_stat[item], amount, BDI_STAT_BATCH); +} + +static inline void __inc_bdi_stat(struct backing_dev_info *bdi, + enum bdi_stat_item item) +{ + __add_bdi_stat(bdi, item, 1); +} + +static inline void inc_bdi_stat(struct backing_dev_info *bdi, + enum bdi_stat_item item) +{ + unsigned long flags; + + local_irq_save(flags); + __inc_bdi_stat(bdi, item); + local_irq_restore(flags); +} + +static inline void __dec_bdi_stat(struct backing_dev_info *bdi, + enum bdi_stat_item item) +{ + __add_bdi_stat(bdi, item, -1); +} + +static inline void dec_bdi_stat(struct backing_dev_info *bdi, + enum bdi_stat_item item) +{ + unsigned long flags; + + local_irq_save(flags); + __dec_bdi_stat(bdi, item); + local_irq_restore(flags); +} + +static inline s64 bdi_stat(struct backing_dev_info *bdi, + enum bdi_stat_item item) +{ + return percpu_counter_read_positive(&bdi->bdi_stat[item]); +} + +static inline s64 __bdi_stat_sum(struct backing_dev_info *bdi, + enum bdi_stat_item item) +{ + return percpu_counter_sum_positive(&bdi->bdi_stat[item]); +} + +static inline s64 bdi_stat_sum(struct backing_dev_info *bdi, + enum bdi_stat_item item) +{ + s64 sum; + unsigned long flags; + + local_irq_save(flags); + sum = __bdi_stat_sum(bdi, item); + local_irq_restore(flags); + + return sum; +} + +extern void bdi_writeout_inc(struct backing_dev_info *bdi); + +/* + * maximal error of a stat counter. + */ +static inline unsigned long bdi_stat_error(struct backing_dev_info *bdi) +{ +#ifdef CONFIG_SMP + return nr_cpu_ids * BDI_STAT_BATCH; +#else + return 1; +#endif +} + +int bdi_set_min_ratio(struct backing_dev_info *bdi, unsigned int min_ratio); +int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); + +/* + * Flags in backing_dev_info::capability + * + * The first three flags control whether dirty pages will contribute to the + * VM's accounting and whether writepages() should be called for dirty pages + * (something that would not, for example, be appropriate for ramfs) + * + * WARNING: these flags are closely related and should not normally be + * used separately. The BDI_CAP_NO_ACCT_AND_WRITEBACK combines these + * three flags into a single convenience macro. + * + * BDI_CAP_NO_ACCT_DIRTY: Dirty pages shouldn't contribute to accounting + * BDI_CAP_NO_WRITEBACK: Don't write pages back + * BDI_CAP_NO_ACCT_WB: Don't automatically account writeback pages + * BDI_CAP_STRICTLIMIT: Keep number of dirty pages below bdi threshold. + */ +#define BDI_CAP_NO_ACCT_DIRTY 0x00000001 +#define BDI_CAP_NO_WRITEBACK 0x00000002 +#define BDI_CAP_NO_ACCT_WB 0x00000004 +#define BDI_CAP_STABLE_WRITES 0x00000008 +#define BDI_CAP_STRICTLIMIT 0x00000010 + +#define BDI_CAP_NO_ACCT_AND_WRITEBACK \ + (BDI_CAP_NO_WRITEBACK | BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_ACCT_WB) + +extern struct backing_dev_info noop_backing_dev_info; + +int writeback_in_progress(struct backing_dev_info *bdi); + +static inline int bdi_congested(struct backing_dev_info *bdi, int bdi_bits) +{ + if (bdi->congested_fn) + return bdi->congested_fn(bdi->congested_data, bdi_bits); + return (bdi->state & bdi_bits); +} + +static inline int bdi_read_congested(struct backing_dev_info *bdi) +{ + return bdi_congested(bdi, 1 << BDI_sync_congested); +} + +static inline int bdi_write_congested(struct backing_dev_info *bdi) +{ + return bdi_congested(bdi, 1 << BDI_async_congested); +} + +static inline int bdi_rw_congested(struct backing_dev_info *bdi) +{ + return bdi_congested(bdi, (1 << BDI_sync_congested) | + (1 << BDI_async_congested)); +} + +enum { + BLK_RW_ASYNC = 0, + BLK_RW_SYNC = 1, +}; + +void clear_bdi_congested(struct backing_dev_info *bdi, int sync); +void set_bdi_congested(struct backing_dev_info *bdi, int sync); +long congestion_wait(int sync, long timeout); +long wait_iff_congested(struct zone *zone, int sync, long timeout); +int pdflush_proc_obsolete(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos); + +static inline bool bdi_cap_stable_pages_required(struct backing_dev_info *bdi) +{ + return bdi->capabilities & BDI_CAP_STABLE_WRITES; +} + +static inline bool bdi_cap_writeback_dirty(struct backing_dev_info *bdi) +{ + return !(bdi->capabilities & BDI_CAP_NO_WRITEBACK); +} + +static inline bool bdi_cap_account_dirty(struct backing_dev_info *bdi) +{ + return !(bdi->capabilities & BDI_CAP_NO_ACCT_DIRTY); +} + +static inline bool bdi_cap_account_writeback(struct backing_dev_info *bdi) +{ + /* Paranoia: BDI_CAP_NO_WRITEBACK implies BDI_CAP_NO_ACCT_WB */ + return !(bdi->capabilities & (BDI_CAP_NO_ACCT_WB | + BDI_CAP_NO_WRITEBACK)); +} + +static inline bool mapping_cap_writeback_dirty(struct address_space *mapping) +{ + return bdi_cap_writeback_dirty(inode_to_bdi(mapping->host)); +} + +static inline bool mapping_cap_account_dirty(struct address_space *mapping) +{ + return bdi_cap_account_dirty(inode_to_bdi(mapping->host)); +} + +static inline int bdi_sched_wait(void *word) +{ + schedule(); + return 0; +} + +#endif /* _LINUX_BACKING_DEV_H */ -- cgit 1.2.3-korg