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@@ -282,10 +282,8 @@
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#define LONGS(x) (((x) + sizeof(unsigned long) - 1)/sizeof(unsigned long))
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/*
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- * To allow fractional bits to be tracked, the following fields contain
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- * this many fractional bits:
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- *
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- * entropy_count, trickle_thresh
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+ * To allow fractional bits to be tracked, the entropy_count field is
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+ * denominated in units of 1/8th bits.
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*
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* 2*(ENTROPY_SHIFT + log2(poolbits)) must <= 31, or the multiply in
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* credit_entropy_bits() needs to be 64 bits wide.
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@@ -313,14 +311,6 @@ static int random_write_wakeup_thresh = 128;
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*/
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static int random_min_urandom_seed = 60;
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-/*
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- * When the input pool goes over trickle_thresh, start dropping most
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- * samples to avoid wasting CPU time and reduce lock contention.
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- */
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-static const int trickle_thresh = (INPUT_POOL_WORDS * 28) << ENTROPY_SHIFT;
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-
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-static DEFINE_PER_CPU(int, trickle_count);
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-
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/*
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* Originally, we used a primitive polynomial of degree .poolwords
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* over GF(2). The taps for various sizes are defined below. They
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@@ -755,10 +745,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
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long delta, delta2, delta3;
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preempt_disable();
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- /* if over the trickle threshold, use only 1 in 4096 samples */
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- if (ENTROPY_BITS(&input_pool) > trickle_thresh &&
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- ((__this_cpu_inc_return(trickle_count) - 1) & 0xfff))
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- goto out;
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sample.jiffies = jiffies;
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sample.cycles = random_get_entropy();
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@@ -800,7 +786,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num)
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credit_entropy_bits(&input_pool,
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min_t(int, fls(delta>>1), 11));
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}
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-out:
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preempt_enable();
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}
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