From 3060d6fe28570640c2d7d66d38b9eaa848c3b9e3 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Tue, 19 Aug 2008 20:50:08 -0700 Subject: x86: put timer_rand_state pointer into irq_desc irq_timer_state[] is a NR_IRQS sized array that is a side-by array to the real irq_desc[] array. Integrate that field into the (now dynamic) irq_desc dynamic array and save some RAM. v2: keep the old way to support arch not support irq_desc Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- drivers/char/random.c | 66 +++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 61 insertions(+), 5 deletions(-) (limited to 'drivers/char/random.c') diff --git a/drivers/char/random.c b/drivers/char/random.c index 1610aa64c7c..60c9c7ee6b2 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -558,7 +558,7 @@ struct timer_rand_state { unsigned dont_count_entropy:1; }; -static struct timer_rand_state input_timer_state; +#ifndef CONFIG_HAVE_SPARSE_IRQ #ifdef CONFIG_HAVE_DYN_ARRAY static struct timer_rand_state **irq_timer_state; @@ -567,6 +567,51 @@ DEFINE_DYN_ARRAY(irq_timer_state, sizeof(struct timer_rand_state *), nr_irqs, PA static struct timer_rand_state *irq_timer_state[NR_IRQS]; #endif +static struct timer_rand_state *get_timer_rand_state(unsigned int irq) +{ + if (irq >= nr_irqs) + return NULL; + + return irq_timer_state[irq]; +} + +static void set_timer_rand_state(unsigned int irq, struct timer_rand_state *state) +{ + if (irq >= nr_irqs) + return; + + irq_timer_state[irq] = state; +} + +#else + +static struct timer_rand_state *get_timer_rand_state(unsigned int irq) +{ + struct irq_desc *desc; + + desc = irq_to_desc(irq); + + if (!desc) + return NULL; + + return desc->timer_rand_state; +} + +static void set_timer_rand_state(unsigned int irq, struct timer_rand_state *state) +{ + struct irq_desc *desc; + + desc = irq_to_desc(irq); + + if (!desc) + return; + + desc->timer_rand_state = state; +} +#endif + +static struct timer_rand_state input_timer_state; + /* * This function adds entropy to the entropy "pool" by using timing * delays. It uses the timer_rand_state structure to make an estimate @@ -654,11 +699,15 @@ EXPORT_SYMBOL_GPL(add_input_randomness); void add_interrupt_randomness(int irq) { - if (irq >= nr_irqs || irq_timer_state[irq] == NULL) + struct timer_rand_state *state; + + state = get_timer_rand_state(irq); + + if (state == NULL) return; DEBUG_ENT("irq event %d\n", irq); - add_timer_randomness(irq_timer_state[irq], 0x100 + irq); + add_timer_randomness(state, 0x100 + irq); } #ifdef CONFIG_BLOCK @@ -918,7 +967,14 @@ void rand_initialize_irq(int irq) { struct timer_rand_state *state; - if (irq >= nr_irqs || irq_timer_state[irq]) +#ifndef CONFIG_HAVE_SPARSE_IRQ + if (irq >= nr_irqs) + return; +#endif + + state = get_timer_rand_state(irq); + + if (state) return; /* @@ -927,7 +983,7 @@ void rand_initialize_irq(int irq) */ state = kzalloc(sizeof(struct timer_rand_state), GFP_KERNEL); if (state) - irq_timer_state[irq] = state; + set_timer_rand_state(irq, state); } #ifdef CONFIG_BLOCK -- cgit v1.2.3