lkml.org 
[lkml]   [2008]   [Dec]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/3] dm-target: use pointer reference instead of making a copy
Date
From: Cheng Renquan <crquan@gmail.com>

The tt_internal always use target_type read-only, so there's no need to
making a copy, just a pointer reference is good, this could save
(sizeof(target_type) - sizeof(pointer)) bytes memory per target_type.

- ti->tt = *t;
+ ti->tt = t;

Signed-off-by: Cheng Renquan <crquan@gmail.com>
---
drivers/md/dm-target.c | 16 ++++++++--------
1 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
index 018df35..a713c7f 100644
--- a/drivers/md/dm-target.c
+++ b/drivers/md/dm-target.c
@@ -15,7 +15,7 @@
#define DM_MSG_PREFIX "target"

struct tt_internal {
- struct target_type tt;
+ struct target_type *tt;

struct list_head list;
};
@@ -30,7 +30,7 @@ static inline struct tt_internal *__find_target_type(const char *name)
struct tt_internal *ti;

list_for_each_entry (ti, &_targets, list)
- if (!strcmp(name, ti->tt.name))
+ if (!strcmp(name, ti->tt->name))
return ti;

return NULL;
@@ -43,7 +43,7 @@ static struct tt_internal *get_target_type(const char *name)
down_read(&_lock);

ti = __find_target_type(name);
- if (ti && !try_module_get(ti->tt.module))
+ if (ti && !try_module_get(ti->tt->module))
ti = NULL;

up_read(&_lock);
@@ -64,7 +64,7 @@ struct target_type *dm_get_target_type(const char *name)
ti = get_target_type(name);
}

- return ti ? &ti->tt : NULL;
+ return ti ? ti->tt : NULL;
}

void dm_put_target_type(struct target_type *t)
@@ -72,7 +72,7 @@ void dm_put_target_type(struct target_type *t)
struct tt_internal *ti = (struct tt_internal *) t;

down_read(&_lock);
- module_put(ti->tt.module);
+ module_put(ti->tt->module);
up_read(&_lock);

return;
@@ -83,7 +83,7 @@ static struct tt_internal *alloc_target(struct target_type *t)
struct tt_internal *ti = kzalloc(sizeof(*ti), GFP_KERNEL);

if (ti)
- ti->tt = *t;
+ ti->tt = t;

return ti;
}
@@ -96,7 +96,7 @@ int dm_target_iterate(void (*iter_func)(struct target_type *tt,

down_read(&_lock);
list_for_each_entry (ti, &_targets, list)
- iter_func(&ti->tt, param);
+ iter_func(ti->tt, param);
up_read(&_lock);

return 0;
@@ -132,7 +132,7 @@ int dm_unregister_target(struct target_type *t)
return -EINVAL;
}

- if (ti->tt.module && module_refcount(ti->tt.module)) {
+ if (ti->tt->module && module_refcount(ti->tt->module)) {
up_write(&_lock);
return -ETXTBSY;
}
--
1.6.0.2.GIT


\
 
 \ /
  Last update: 2008-12-19 05:23    [W:0.125 / U:0.456 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site