evie/android_kernel_oneplus_msm8998
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random: optimize the entropy_store structure

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Use smaller types to slightly shrink the size of the entropy store
structure.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o 2013-09-21 19:42:41 -04:00
parent 3ef4cb2d65
commit c59974aea4
1 changed files with 8 additions and 8 deletions
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16
drivers/char/random.c
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@ -436,16 +436,16 @@ struct entropy_store {
__u32 *pool; __u32 *pool;
const char *name; const char *name;
struct entropy_store *pull; struct entropy_store *pull;
int limit;
/* read-write data: */ /* read-write data: */
spinlock_t lock; spinlock_t lock;
unsigned add_ptr; unsigned short add_ptr;
unsigned input_rotate; unsigned short input_rotate;
int entropy_count; int entropy_count;
int entropy_total; int entropy_total;
unsigned int initialized:1; unsigned int initialized:1;
bool last_data_init; unsigned int limit:1;
unsigned int last_data_init:1;
__u8 last_data[EXTRACT_SIZE]; __u8 last_data[EXTRACT_SIZE];
}; };
@ -513,7 +513,7 @@ static void _mix_pool_bytes(struct entropy_store *r, const void *in,
/* mix one byte at a time to simplify size handling and churn faster */ /* mix one byte at a time to simplify size handling and churn faster */
while (nbytes--) { while (nbytes--) {
w = rol32(*bytes++, input_rotate & 31); w = rol32(*bytes++, input_rotate);
i = (i - 1) & wordmask; i = (i - 1) & wordmask;
/* XOR in the various taps */ /* XOR in the various taps */
@ -533,7 +533,7 @@ static void _mix_pool_bytes(struct entropy_store *r, const void *in,
* rotation, so that successive passes spread the * rotation, so that successive passes spread the
* input bits across the pool evenly. * input bits across the pool evenly.
*/ */
input_rotate += i ? 7 : 14; input_rotate = (input_rotate + (i ? 7 : 14)) & 31;
} }
ACCESS_ONCE(r->input_rotate) = input_rotate; ACCESS_ONCE(r->input_rotate) = input_rotate;
@ -1049,7 +1049,7 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf,
if (fips_enabled) { if (fips_enabled) {
spin_lock_irqsave(&r->lock, flags); spin_lock_irqsave(&r->lock, flags);
if (!r->last_data_init) { if (!r->last_data_init) {
r->last_data_init = true; r->last_data_init = 1;
spin_unlock_irqrestore(&r->lock, flags); spin_unlock_irqrestore(&r->lock, flags);
trace_extract_entropy(r->name, EXTRACT_SIZE, trace_extract_entropy(r->name, EXTRACT_SIZE,
ENTROPY_BITS(r), _RET_IP_); ENTROPY_BITS(r), _RET_IP_);
@ -1189,7 +1189,7 @@ static void init_std_data(struct entropy_store *r)
r->entropy_count = 0; r->entropy_count = 0;
r->entropy_total = 0; r->entropy_total = 0;
r->last_data_init = false; r->last_data_init = 0;
mix_pool_bytes(r, &now, sizeof(now), NULL); mix_pool_bytes(r, &now, sizeof(now), NULL);
for (i = r->poolinfo->poolbytes; i > 0; i -= sizeof(rv)) { for (i = r->poolinfo->poolbytes; i > 0; i -= sizeof(rv)) {
if (!arch_get_random_long(&rv)) if (!arch_get_random_long(&rv))