Messages in this thread Patch in this message | | | Date | Sun, 12 Sep 2010 23:50:01 +0800 | From | Wu Fengguang <> | Subject | [PATCH 16/17] mm: create /vm/dirty_pressure in debugfs |
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Create /debug/vm/ -- a convenient place for kernel hackers to play with VM variables.
The first exported is vm_dirty_pressure for avoiding excessive pageout()s. It ranges from 0 to 1024, the lower value, the lower dirty limit.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> --- mm/vmstat.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-)
--- linux-next.orig/mm/vmstat.c 2010-09-12 09:50:57.000000000 +0800 +++ linux-next/mm/vmstat.c 2010-09-12 13:27:44.000000000 +0800 @@ -1045,9 +1045,33 @@ static int __init setup_vmstat(void) } module_init(setup_vmstat) -#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION) +#if defined(CONFIG_DEBUG_FS) #include <linux/debugfs.h> +#include <linux/writeback.h> +static struct dentry *vm_debug_root; + +static int __init vm_debug_init(void) +{ + struct dentry *dentry; + + vm_debug_root = debugfs_create_dir("vm", NULL); + if (!vm_debug_root) + goto fail; + + dentry = debugfs_create_u32("dirty_pressure", 0644, + vm_debug_root, &vm_dirty_pressure); + if (!dentry) + goto fail; + + return 0; +fail: + return -ENOMEM; +} + +module_init(vm_debug_init); + +#if defined(CONFIG_COMPACTION) static struct dentry *extfrag_debug_root; /* @@ -1202,4 +1226,5 @@ static int __init extfrag_debug_init(voi } module_init(extfrag_debug_init); -#endif +#endif /* CONFIG_COMPACTION */ +#endif /* CONFIG_DEBUG_FS */
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