kernel-fxtec-pro1x/include/trace/events/writeback.h
Wu Fengguang 83712358ba writeback: dirty ratelimit - think time compensation
Compensate the task's think time when computing the final pause time,
so that ->dirty_ratelimit can be executed accurately.

        think time := time spend outside of balance_dirty_pages()

In the rare case that the task slept longer than the 200ms period time
(result in negative pause time), the sleep time will be compensated in
the following periods, too, if it's less than 1 second.

Accumulated errors are carefully avoided as long as the max pause area
is not hitted.

Pseudo code:

        period = pages_dirtied / task_ratelimit;
        think = jiffies - dirty_paused_when;
        pause = period - think;

1) normal case: period > think

        pause = period - think
        dirty_paused_when = jiffies + pause
        nr_dirtied = 0

                             period time
              |===============================>|
                  think time      pause time
              |===============>|==============>|
        ------|----------------|---------------|------------------------
        dirty_paused_when   jiffies

2) no pause case: period <= think

        don't pause; reduce future pause time by:
        dirty_paused_when += period
        nr_dirtied = 0

                           period time
              |===============================>|
                                  think time
              |===================================================>|
        ------|--------------------------------+-------------------|----
        dirty_paused_when                                       jiffies

Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
2011-12-18 14:20:27 +08:00

468 lines
13 KiB
C

#undef TRACE_SYSTEM
#define TRACE_SYSTEM writeback
#if !defined(_TRACE_WRITEBACK_H) || defined(TRACE_HEADER_MULTI_READ)
#define _TRACE_WRITEBACK_H
#include <linux/backing-dev.h>
#include <linux/device.h>
#include <linux/writeback.h>
#define show_inode_state(state) \
__print_flags(state, "|", \
{I_DIRTY_SYNC, "I_DIRTY_SYNC"}, \
{I_DIRTY_DATASYNC, "I_DIRTY_DATASYNC"}, \
{I_DIRTY_PAGES, "I_DIRTY_PAGES"}, \
{I_NEW, "I_NEW"}, \
{I_WILL_FREE, "I_WILL_FREE"}, \
{I_FREEING, "I_FREEING"}, \
{I_CLEAR, "I_CLEAR"}, \
{I_SYNC, "I_SYNC"}, \
{I_REFERENCED, "I_REFERENCED"} \
)
#define WB_WORK_REASON \
{WB_REASON_BACKGROUND, "background"}, \
{WB_REASON_TRY_TO_FREE_PAGES, "try_to_free_pages"}, \
{WB_REASON_SYNC, "sync"}, \
{WB_REASON_PERIODIC, "periodic"}, \
{WB_REASON_LAPTOP_TIMER, "laptop_timer"}, \
{WB_REASON_FREE_MORE_MEM, "free_more_memory"}, \
{WB_REASON_FS_FREE_SPACE, "fs_free_space"}, \
{WB_REASON_FORKER_THREAD, "forker_thread"}
struct wb_writeback_work;
DECLARE_EVENT_CLASS(writeback_work_class,
TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work),
TP_ARGS(bdi, work),
TP_STRUCT__entry(
__array(char, name, 32)
__field(long, nr_pages)
__field(dev_t, sb_dev)
__field(int, sync_mode)
__field(int, for_kupdate)
__field(int, range_cyclic)
__field(int, for_background)
__field(int, reason)
),
TP_fast_assign(
strncpy(__entry->name, dev_name(bdi->dev), 32);
__entry->nr_pages = work->nr_pages;
__entry->sb_dev = work->sb ? work->sb->s_dev : 0;
__entry->sync_mode = work->sync_mode;
__entry->for_kupdate = work->for_kupdate;
__entry->range_cyclic = work->range_cyclic;
__entry->for_background = work->for_background;
__entry->reason = work->reason;
),
TP_printk("bdi %s: sb_dev %d:%d nr_pages=%ld sync_mode=%d "
"kupdate=%d range_cyclic=%d background=%d reason=%s",
__entry->name,
MAJOR(__entry->sb_dev), MINOR(__entry->sb_dev),
__entry->nr_pages,
__entry->sync_mode,
__entry->for_kupdate,
__entry->range_cyclic,
__entry->for_background,
__print_symbolic(__entry->reason, WB_WORK_REASON)
)
);
#define DEFINE_WRITEBACK_WORK_EVENT(name) \
DEFINE_EVENT(writeback_work_class, name, \
TP_PROTO(struct backing_dev_info *bdi, struct wb_writeback_work *work), \
TP_ARGS(bdi, work))
DEFINE_WRITEBACK_WORK_EVENT(writeback_nothread);
DEFINE_WRITEBACK_WORK_EVENT(writeback_queue);
DEFINE_WRITEBACK_WORK_EVENT(writeback_exec);
DEFINE_WRITEBACK_WORK_EVENT(writeback_start);
DEFINE_WRITEBACK_WORK_EVENT(writeback_written);
DEFINE_WRITEBACK_WORK_EVENT(writeback_wait);
TRACE_EVENT(writeback_pages_written,
TP_PROTO(long pages_written),
TP_ARGS(pages_written),
TP_STRUCT__entry(
__field(long, pages)
),
TP_fast_assign(
__entry->pages = pages_written;
),
TP_printk("%ld", __entry->pages)
);
DECLARE_EVENT_CLASS(writeback_class,
TP_PROTO(struct backing_dev_info *bdi),
TP_ARGS(bdi),
TP_STRUCT__entry(
__array(char, name, 32)
),
TP_fast_assign(
strncpy(__entry->name, dev_name(bdi->dev), 32);
),
TP_printk("bdi %s",
__entry->name
)
);
#define DEFINE_WRITEBACK_EVENT(name) \
DEFINE_EVENT(writeback_class, name, \
TP_PROTO(struct backing_dev_info *bdi), \
TP_ARGS(bdi))
DEFINE_WRITEBACK_EVENT(writeback_nowork);
DEFINE_WRITEBACK_EVENT(writeback_wake_background);
DEFINE_WRITEBACK_EVENT(writeback_wake_thread);
DEFINE_WRITEBACK_EVENT(writeback_wake_forker_thread);
DEFINE_WRITEBACK_EVENT(writeback_bdi_register);
DEFINE_WRITEBACK_EVENT(writeback_bdi_unregister);
DEFINE_WRITEBACK_EVENT(writeback_thread_start);
DEFINE_WRITEBACK_EVENT(writeback_thread_stop);
DECLARE_EVENT_CLASS(wbc_class,
TP_PROTO(struct writeback_control *wbc, struct backing_dev_info *bdi),
TP_ARGS(wbc, bdi),
TP_STRUCT__entry(
__array(char, name, 32)
__field(long, nr_to_write)
__field(long, pages_skipped)
__field(int, sync_mode)
__field(int, for_kupdate)
__field(int, for_background)
__field(int, for_reclaim)
__field(int, range_cyclic)
__field(long, range_start)
__field(long, range_end)
),
TP_fast_assign(
strncpy(__entry->name, dev_name(bdi->dev), 32);
__entry->nr_to_write = wbc->nr_to_write;
__entry->pages_skipped = wbc->pages_skipped;
__entry->sync_mode = wbc->sync_mode;
__entry->for_kupdate = wbc->for_kupdate;
__entry->for_background = wbc->for_background;
__entry->for_reclaim = wbc->for_reclaim;
__entry->range_cyclic = wbc->range_cyclic;
__entry->range_start = (long)wbc->range_start;
__entry->range_end = (long)wbc->range_end;
),
TP_printk("bdi %s: towrt=%ld skip=%ld mode=%d kupd=%d "
"bgrd=%d reclm=%d cyclic=%d "
"start=0x%lx end=0x%lx",
__entry->name,
__entry->nr_to_write,
__entry->pages_skipped,
__entry->sync_mode,
__entry->for_kupdate,
__entry->for_background,
__entry->for_reclaim,
__entry->range_cyclic,
__entry->range_start,
__entry->range_end)
)
#define DEFINE_WBC_EVENT(name) \
DEFINE_EVENT(wbc_class, name, \
TP_PROTO(struct writeback_control *wbc, struct backing_dev_info *bdi), \
TP_ARGS(wbc, bdi))
DEFINE_WBC_EVENT(wbc_writepage);
TRACE_EVENT(writeback_queue_io,
TP_PROTO(struct bdi_writeback *wb,
struct wb_writeback_work *work,
int moved),
TP_ARGS(wb, work, moved),
TP_STRUCT__entry(
__array(char, name, 32)
__field(unsigned long, older)
__field(long, age)
__field(int, moved)
__field(int, reason)
),
TP_fast_assign(
unsigned long *older_than_this = work->older_than_this;
strncpy(__entry->name, dev_name(wb->bdi->dev), 32);
__entry->older = older_than_this ? *older_than_this : 0;
__entry->age = older_than_this ?
(jiffies - *older_than_this) * 1000 / HZ : -1;
__entry->moved = moved;
__entry->reason = work->reason;
),
TP_printk("bdi %s: older=%lu age=%ld enqueue=%d reason=%s",
__entry->name,
__entry->older, /* older_than_this in jiffies */
__entry->age, /* older_than_this in relative milliseconds */
__entry->moved,
__print_symbolic(__entry->reason, WB_WORK_REASON)
)
);
TRACE_EVENT(global_dirty_state,
TP_PROTO(unsigned long background_thresh,
unsigned long dirty_thresh
),
TP_ARGS(background_thresh,
dirty_thresh
),
TP_STRUCT__entry(
__field(unsigned long, nr_dirty)
__field(unsigned long, nr_writeback)
__field(unsigned long, nr_unstable)
__field(unsigned long, background_thresh)
__field(unsigned long, dirty_thresh)
__field(unsigned long, dirty_limit)
__field(unsigned long, nr_dirtied)
__field(unsigned long, nr_written)
),
TP_fast_assign(
__entry->nr_dirty = global_page_state(NR_FILE_DIRTY);
__entry->nr_writeback = global_page_state(NR_WRITEBACK);
__entry->nr_unstable = global_page_state(NR_UNSTABLE_NFS);
__entry->nr_dirtied = global_page_state(NR_DIRTIED);
__entry->nr_written = global_page_state(NR_WRITTEN);
__entry->background_thresh = background_thresh;
__entry->dirty_thresh = dirty_thresh;
__entry->dirty_limit = global_dirty_limit;
),
TP_printk("dirty=%lu writeback=%lu unstable=%lu "
"bg_thresh=%lu thresh=%lu limit=%lu "
"dirtied=%lu written=%lu",
__entry->nr_dirty,
__entry->nr_writeback,
__entry->nr_unstable,
__entry->background_thresh,
__entry->dirty_thresh,
__entry->dirty_limit,
__entry->nr_dirtied,
__entry->nr_written
)
);
#define KBps(x) ((x) << (PAGE_SHIFT - 10))
TRACE_EVENT(bdi_dirty_ratelimit,
TP_PROTO(struct backing_dev_info *bdi,
unsigned long dirty_rate,
unsigned long task_ratelimit),
TP_ARGS(bdi, dirty_rate, task_ratelimit),
TP_STRUCT__entry(
__array(char, bdi, 32)
__field(unsigned long, write_bw)
__field(unsigned long, avg_write_bw)
__field(unsigned long, dirty_rate)
__field(unsigned long, dirty_ratelimit)
__field(unsigned long, task_ratelimit)
__field(unsigned long, balanced_dirty_ratelimit)
),
TP_fast_assign(
strlcpy(__entry->bdi, dev_name(bdi->dev), 32);
__entry->write_bw = KBps(bdi->write_bandwidth);
__entry->avg_write_bw = KBps(bdi->avg_write_bandwidth);
__entry->dirty_rate = KBps(dirty_rate);
__entry->dirty_ratelimit = KBps(bdi->dirty_ratelimit);
__entry->task_ratelimit = KBps(task_ratelimit);
__entry->balanced_dirty_ratelimit =
KBps(bdi->balanced_dirty_ratelimit);
),
TP_printk("bdi %s: "
"write_bw=%lu awrite_bw=%lu dirty_rate=%lu "
"dirty_ratelimit=%lu task_ratelimit=%lu "
"balanced_dirty_ratelimit=%lu",
__entry->bdi,
__entry->write_bw, /* write bandwidth */
__entry->avg_write_bw, /* avg write bandwidth */
__entry->dirty_rate, /* bdi dirty rate */
__entry->dirty_ratelimit, /* base ratelimit */
__entry->task_ratelimit, /* ratelimit with position control */
__entry->balanced_dirty_ratelimit /* the balanced ratelimit */
)
);
TRACE_EVENT(balance_dirty_pages,
TP_PROTO(struct backing_dev_info *bdi,
unsigned long thresh,
unsigned long bg_thresh,
unsigned long dirty,
unsigned long bdi_thresh,
unsigned long bdi_dirty,
unsigned long dirty_ratelimit,
unsigned long task_ratelimit,
unsigned long dirtied,
unsigned long period,
long pause,
unsigned long start_time),
TP_ARGS(bdi, thresh, bg_thresh, dirty, bdi_thresh, bdi_dirty,
dirty_ratelimit, task_ratelimit,
dirtied, period, pause, start_time),
TP_STRUCT__entry(
__array( char, bdi, 32)
__field(unsigned long, limit)
__field(unsigned long, setpoint)
__field(unsigned long, dirty)
__field(unsigned long, bdi_setpoint)
__field(unsigned long, bdi_dirty)
__field(unsigned long, dirty_ratelimit)
__field(unsigned long, task_ratelimit)
__field(unsigned int, dirtied)
__field(unsigned int, dirtied_pause)
__field(unsigned long, paused)
__field( long, pause)
__field(unsigned long, period)
__field( long, think)
),
TP_fast_assign(
unsigned long freerun = (thresh + bg_thresh) / 2;
strlcpy(__entry->bdi, dev_name(bdi->dev), 32);
__entry->limit = global_dirty_limit;
__entry->setpoint = (global_dirty_limit + freerun) / 2;
__entry->dirty = dirty;
__entry->bdi_setpoint = __entry->setpoint *
bdi_thresh / (thresh + 1);
__entry->bdi_dirty = bdi_dirty;
__entry->dirty_ratelimit = KBps(dirty_ratelimit);
__entry->task_ratelimit = KBps(task_ratelimit);
__entry->dirtied = dirtied;
__entry->dirtied_pause = current->nr_dirtied_pause;
__entry->think = current->dirty_paused_when == 0 ? 0 :
(long)(jiffies - current->dirty_paused_when) * 1000/HZ;
__entry->period = period * 1000 / HZ;
__entry->pause = pause * 1000 / HZ;
__entry->paused = (jiffies - start_time) * 1000 / HZ;
),
TP_printk("bdi %s: "
"limit=%lu setpoint=%lu dirty=%lu "
"bdi_setpoint=%lu bdi_dirty=%lu "
"dirty_ratelimit=%lu task_ratelimit=%lu "
"dirtied=%u dirtied_pause=%u "
"paused=%lu pause=%ld period=%lu think=%ld",
__entry->bdi,
__entry->limit,
__entry->setpoint,
__entry->dirty,
__entry->bdi_setpoint,
__entry->bdi_dirty,
__entry->dirty_ratelimit,
__entry->task_ratelimit,
__entry->dirtied,
__entry->dirtied_pause,
__entry->paused, /* ms */
__entry->pause, /* ms */
__entry->period, /* ms */
__entry->think /* ms */
)
);
DECLARE_EVENT_CLASS(writeback_congest_waited_template,
TP_PROTO(unsigned int usec_timeout, unsigned int usec_delayed),
TP_ARGS(usec_timeout, usec_delayed),
TP_STRUCT__entry(
__field( unsigned int, usec_timeout )
__field( unsigned int, usec_delayed )
),
TP_fast_assign(
__entry->usec_timeout = usec_timeout;
__entry->usec_delayed = usec_delayed;
),
TP_printk("usec_timeout=%u usec_delayed=%u",
__entry->usec_timeout,
__entry->usec_delayed)
);
DEFINE_EVENT(writeback_congest_waited_template, writeback_congestion_wait,
TP_PROTO(unsigned int usec_timeout, unsigned int usec_delayed),
TP_ARGS(usec_timeout, usec_delayed)
);
DEFINE_EVENT(writeback_congest_waited_template, writeback_wait_iff_congested,
TP_PROTO(unsigned int usec_timeout, unsigned int usec_delayed),
TP_ARGS(usec_timeout, usec_delayed)
);
DECLARE_EVENT_CLASS(writeback_single_inode_template,
TP_PROTO(struct inode *inode,
struct writeback_control *wbc,
unsigned long nr_to_write
),
TP_ARGS(inode, wbc, nr_to_write),
TP_STRUCT__entry(
__array(char, name, 32)
__field(unsigned long, ino)
__field(unsigned long, state)
__field(unsigned long, dirtied_when)
__field(unsigned long, writeback_index)
__field(long, nr_to_write)
__field(unsigned long, wrote)
),
TP_fast_assign(
strncpy(__entry->name,
dev_name(inode->i_mapping->backing_dev_info->dev), 32);
__entry->ino = inode->i_ino;
__entry->state = inode->i_state;
__entry->dirtied_when = inode->dirtied_when;
__entry->writeback_index = inode->i_mapping->writeback_index;
__entry->nr_to_write = nr_to_write;
__entry->wrote = nr_to_write - wbc->nr_to_write;
),
TP_printk("bdi %s: ino=%lu state=%s dirtied_when=%lu age=%lu "
"index=%lu to_write=%ld wrote=%lu",
__entry->name,
__entry->ino,
show_inode_state(__entry->state),
__entry->dirtied_when,
(jiffies - __entry->dirtied_when) / HZ,
__entry->writeback_index,
__entry->nr_to_write,
__entry->wrote
)
);
DEFINE_EVENT(writeback_single_inode_template, writeback_single_inode_requeue,
TP_PROTO(struct inode *inode,
struct writeback_control *wbc,
unsigned long nr_to_write),
TP_ARGS(inode, wbc, nr_to_write)
);
DEFINE_EVENT(writeback_single_inode_template, writeback_single_inode,
TP_PROTO(struct inode *inode,
struct writeback_control *wbc,
unsigned long nr_to_write),
TP_ARGS(inode, wbc, nr_to_write)
);
#endif /* _TRACE_WRITEBACK_H */
/* This part must be outside protection */
#include <trace/define_trace.h>