linux-ext4 - [PATCH 3/5] mbcache: remove unnecessary module_get/module

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Message-Id: <1480227481-98535-3-git-send-email-ebiggers@google.com>
Date:   Sat, 26 Nov 2016 22:17:59 -0800
From:   Eric Biggers <ebiggers@...gle.com>
To:     linux-ext4@...r.kernel.org
Cc:     Jan Kara <jack@...e.cz>, Andreas Gruenbacher <agruenba@...hat.com>,
        Eric Biggers <ebiggers@...gle.com>
Subject: [PATCH 3/5] mbcache: remove unnecessary module_get/module_put

When mbcache is built as a module, any modules that use it (ext2 and/or
ext4) will depend on its symbols directly, incrementing its reference
count.  Therefore, there is no need to do module_get/module_put.

Also note that since the module_get/module_put were in the mbcache
module itself, executing those lines of code was already dependent on
another reference to the mbcache module being held.

Signed-off-by: Eric Biggers <ebiggers@...gle.com>
---
 fs/mbcache.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/fs/mbcache.c b/fs/mbcache.c
index c56ab21..07c5d7d 100644
--- a/fs/mbcache.c
+++ b/fs/mbcache.c
@@ -344,9 +344,6 @@ struct mb_cache *mb_cache_create(int bucket_bits)
 	int bucket_count = 1 << bucket_bits;
 	int i;
 
-	if (!try_module_get(THIS_MODULE))
-		return NULL;
-
 	cache = kzalloc(sizeof(struct mb_cache), GFP_KERNEL);
 	if (!cache)
 		goto err_out;
@@ -377,7 +374,6 @@ struct mb_cache *mb_cache_create(int bucket_bits)
 	return cache;
 
 err_out:
-	module_put(THIS_MODULE);
 	return NULL;
 }
 EXPORT_SYMBOL(mb_cache_create);
@@ -411,7 +407,6 @@ void mb_cache_destroy(struct mb_cache *cache)
 	}
 	kfree(cache->c_hash);
 	kfree(cache);
-	module_put(THIS_MODULE);
 }
 EXPORT_SYMBOL(mb_cache_destroy);
 
-- 
2.8.0.rc3.226.g39d4020

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