writeback: trace event bdi_dirty_ratelimit

It helps understand how various throttle bandwidths are updated.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
This commit is contained in:
Wu Fengguang 2011-03-02 17:22:49 -06:00
parent 50657fc4df
commit b48c104d22
2 changed files with 47 additions and 0 deletions

View File

@ -226,6 +226,51 @@ TRACE_EVENT(global_dirty_state,
)
);
#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 */
)
);
DECLARE_EVENT_CLASS(writeback_congest_waited_template,
TP_PROTO(unsigned int usec_timeout, unsigned int usec_delayed),

View File

@ -875,6 +875,8 @@ static void bdi_update_dirty_ratelimit(struct backing_dev_info *bdi,
bdi->dirty_ratelimit = max(dirty_ratelimit, 1UL);
bdi->balanced_dirty_ratelimit = balanced_dirty_ratelimit;
trace_bdi_dirty_ratelimit(bdi, dirty_rate, task_ratelimit);
}
void __bdi_update_bandwidth(struct backing_dev_info *bdi,