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Date: Mon, 17 Jul 2006 19:24:53 -0700
From: "Joshua Hudson" <joshudson@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: How to explain to lock validator: locking inodes in inode order
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Code does this:

/* Lock two items. See locking.txt */
static inline void kb0_lock2m(struct kb0_idata *m1, struct kb0_idata *m2)
{
        if (m1->vi.i_ino > m2->vi.i_ino)
                mutex_lock(&m2->k_mutex);
        mutex_lock(&m1->k_mutex);
        if (m1->vi.i_ino < m2->vi.i_ino)
                mutex_lock(&m2->k_mutex);
}

Not sure how to explain to the lock validator that this code can never deadlock.

Note struct kb0_idata has an element of struct inode called vi.