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random: forget lock in lockless accounting

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The only mutable data accessed here is ->entropy_count, but since
10b3a32d2 ("random: fix accounting race condition") we use cmpxchg to
protect our accesses to ->entropy_count here.  Drop the use of the
lock.

Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Price <price@mit.edu>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Greg Price 2013-11-29 20:09:37 -05:00 committed by Theodore Ts'o
parent ee1de406ba
commit a58aa4edc6
1 changed files with 0 additions and 4 deletions
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4
drivers/char/random.c
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@ -970,9 +970,6 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min,
int entropy_count, orig;
size_t ibytes;
/* Hold lock while accounting */
spin_lock_irqsave(&r->lock, flags);
BUG_ON(r->entropy_count > r->poolinfo->poolfracbits);
/* Can we pull enough? */
@ -995,7 +992,6 @@ retry:
< random_write_wakeup_thresh)
wakeup_write = 1;
}
spin_unlock_irqrestore(&r->lock, flags);
trace_debit_entropy(r->name, 8 * ibytes);
if (wakeup_write) {