From 1c78217fc8c0983f5768a2d1c17c022f1079751e Mon Sep 17 00:00:00 2001 From: Nishanth Menon Date: Thu, 26 May 2011 19:39:20 -0700 Subject: [PATCH] cpufreq: OMAP: fix freq_table leak We use a single frequency table for multiple CPUs. But, with OMAP4, since we have multiple CPUs, the cpu_init call for CPU1 causes freq_table previously allocated for CPU0 to be overwritten. In addition, we dont free the table on exit path. We solve this by maintaining an atomic type counter to ensure just a single table exists at a given time. Signed-off-by: Nishanth Menon Signed-off-by: Kevin Hilman --- drivers/cpufreq/omap-cpufreq.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c index 8c5419201ac..ad94b4f2892 100644 --- a/drivers/cpufreq/omap-cpufreq.c +++ b/drivers/cpufreq/omap-cpufreq.c @@ -46,6 +46,7 @@ static struct lpj_info global_lpj_ref; #endif static struct cpufreq_frequency_table *freq_table; +static atomic_t freq_table_users = ATOMIC_INIT(0); static struct clk *mpu_clk; static char *mpu_clk_name; static struct device *mpu_dev; @@ -150,6 +151,12 @@ static int omap_target(struct cpufreq_policy *policy, return ret; } +static inline void freq_table_free(void) +{ + if (atomic_dec_and_test(&freq_table_users)) + opp_free_cpufreq_table(mpu_dev, &freq_table); +} + static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy) { int result = 0; @@ -164,7 +171,9 @@ static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy) } policy->cur = policy->min = policy->max = omap_getspeed(policy->cpu); - result = opp_init_cpufreq_table(mpu_dev, &freq_table); + + if (atomic_inc_return(&freq_table_users) == 1) + result = opp_init_cpufreq_table(mpu_dev, &freq_table); if (result) { dev_err(mpu_dev, "%s: cpu%d: failed creating freq table[%d]\n", @@ -173,10 +182,10 @@ static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy) } result = cpufreq_frequency_table_cpuinfo(policy, freq_table); - if (!result) - cpufreq_frequency_table_get_attr(freq_table, policy->cpu); - else - goto fail_ck; + if (result) + goto fail_table; + + cpufreq_frequency_table_get_attr(freq_table, policy->cpu); policy->min = policy->cpuinfo.min_freq; policy->max = policy->cpuinfo.max_freq; @@ -199,6 +208,8 @@ static int __cpuinit omap_cpu_init(struct cpufreq_policy *policy) return 0; +fail_table: + freq_table_free(); fail_ck: clk_put(mpu_clk); return result; @@ -206,6 +217,7 @@ fail_ck: static int omap_cpu_exit(struct cpufreq_policy *policy) { + freq_table_free(); clk_put(mpu_clk); return 0; } -- 2.39.5