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| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2008-04-30 00:54:36 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-04-30 08:29:50 -0700 |
| commit | a42dde04152750426cc620fd277e80fffae2f65a (patch) | |
| tree | 98cdf246280c59e0bf044ae6d2c229fc27b73203 /include | |
| parent | 189d3c4a94ef19fca2a71a6a336e9fda900e25e7 (diff) | |
| download | linux-a42dde04152750426cc620fd277e80fffae2f65a.tar.gz linux-a42dde04152750426cc620fd277e80fffae2f65a.tar.bz2 linux-a42dde04152750426cc620fd277e80fffae2f65a.zip | |
mm: bdi: allow setting a maximum for the bdi dirty limit
Add "max_ratio" to /sys/class/bdi. This indicates the maximum percentage of
the global dirty threshold allocated to this bdi.
[mszeredi@suse.cz]
- fix parsing in max_ratio_store().
- export bdi_set_max_ratio() to modules
- limit bdi_dirty with bdi->max_ratio
- document new sysfs attribute
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/backing-dev.h | 2 | ||||
| -rw-r--r-- | include/linux/proportions.h | 13 |
2 files changed, 15 insertions, 0 deletions
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 9a8965518d1d..ad3271d1e90a 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -52,6 +52,7 @@ struct backing_dev_info { int dirty_exceeded; unsigned int min_ratio; + unsigned int max_ratio, max_prop_frac; struct device *dev; }; @@ -140,6 +141,7 @@ static inline unsigned long bdi_stat_error(struct backing_dev_info *bdi) } 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 diff --git a/include/linux/proportions.h b/include/linux/proportions.h index 2c3b3cad92be..5afc1b23346d 100644 --- a/include/linux/proportions.h +++ b/include/linux/proportions.h @@ -78,6 +78,19 @@ void prop_inc_percpu(struct prop_descriptor *pd, struct prop_local_percpu *pl) } /* + * Limit the time part in order to ensure there are some bits left for the + * cycle counter and fraction multiply. + */ +#define PROP_MAX_SHIFT (3*BITS_PER_LONG/4) + +#define PROP_FRAC_SHIFT (BITS_PER_LONG - PROP_MAX_SHIFT - 1) +#define PROP_FRAC_BASE (1UL << PROP_FRAC_SHIFT) + +void __prop_inc_percpu_max(struct prop_descriptor *pd, + struct prop_local_percpu *pl, long frac); + + +/* * ----- SINGLE ------ */ |