9 files changed, 815 insertions, 231 deletions

diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 4b31629c5be4..afce8130d8b9 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -39,9 +39,9 @@ config HIBERNATION
 	bool "Hibernation (aka 'suspend to disk')"
 	depends on SWAP && ARCH_HIBERNATION_POSSIBLE
 	select HIBERNATE_CALLBACKS
-	select LZO_COMPRESS
-	select LZO_DECOMPRESS
 	select CRC32
+	select CRYPTO
+	select CRYPTO_LZO
 	help
 	  Enable the suspend to disk (STD) functionality, which is usually
 	  called "hibernation" in user interfaces.  STD checkpoints the
@@ -92,6 +92,28 @@ config HIBERNATION_SNAPSHOT_DEV
 
 	  If in doubt, say Y.
 
+choice
+	prompt "Default compressor"
+	default HIBERNATION_COMP_LZO
+	depends on HIBERNATION
+
+config HIBERNATION_COMP_LZO
+	bool "lzo"
+	depends on CRYPTO_LZO
+
+config HIBERNATION_COMP_LZ4
+	bool "lz4"
+	depends on CRYPTO_LZ4
+
+endchoice
+
+config HIBERNATION_DEF_COMP
+	string
+	default "lzo" if HIBERNATION_COMP_LZO
+	default "lz4" if HIBERNATION_COMP_LZ4
+	help
+	  Default compressor to be used for hibernation.
+
 config PM_STD_PARTITION
 	string "Default resume partition"
 	depends on HIBERNATION
diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
index 7b44f5b89fa1..b686ac0345bd 100644
--- a/kernel/power/energy_model.c
+++ b/kernel/power/energy_model.c
@@ -23,6 +23,12 @@
  */
 static DEFINE_MUTEX(em_pd_mutex);
 
+static void em_cpufreq_update_efficiencies(struct device *dev,
+					   struct em_perf_state *table);
+static void em_check_capacity_update(void);
+static void em_update_workfn(struct work_struct *work);
+static DECLARE_DELAYED_WORK(em_update_work, em_update_workfn);
+
 static bool _is_cpu_device(struct device *dev)
 {
 	return (dev->bus == &cpu_subsys);
@@ -31,19 +37,65 @@ static bool _is_cpu_device(struct device *dev)
 #ifdef CONFIG_DEBUG_FS
 static struct dentry *rootdir;
 
-static void em_debug_create_ps(struct em_perf_state *ps, struct dentry *pd)
+struct em_dbg_info {
+	struct em_perf_domain *pd;
+	int ps_id;
+};
+
+#define DEFINE_EM_DBG_SHOW(name, fname)					\
+static int em_debug_##fname##_show(struct seq_file *s, void *unused)	\
+{									\
+	struct em_dbg_info *em_dbg = s->private;			\
+	struct em_perf_state *table;					\
+	unsigned long val;						\
+									\
+	rcu_read_lock();						\
+	table = em_perf_state_from_pd(em_dbg->pd);			\
+	val = table[em_dbg->ps_id].name;				\
+	rcu_read_unlock();						\
+									\
+	seq_printf(s, "%lu\n", val);					\
+	return 0;							\
+}									\
+DEFINE_SHOW_ATTRIBUTE(em_debug_##fname)
+
+DEFINE_EM_DBG_SHOW(frequency, frequency);
+DEFINE_EM_DBG_SHOW(power, power);
+DEFINE_EM_DBG_SHOW(cost, cost);
+DEFINE_EM_DBG_SHOW(performance, performance);
+DEFINE_EM_DBG_SHOW(flags, inefficiency);
+
+static void em_debug_create_ps(struct em_perf_domain *em_pd,
+			       struct em_dbg_info *em_dbg, int i,
+			       struct dentry *pd)
 {
+	struct em_perf_state *table;
+	unsigned long freq;
 	struct dentry *d;
 	char name[24];
 
-	snprintf(name, sizeof(name), "ps:%lu", ps->frequency);
+	em_dbg[i].pd = em_pd;
+	em_dbg[i].ps_id = i;
+
+	rcu_read_lock();
+	table = em_perf_state_from_pd(em_pd);
+	freq = table[i].frequency;
+	rcu_read_unlock();
+
+	snprintf(name, sizeof(name), "ps:%lu", freq);
 
 	/* Create per-ps directory */
 	d = debugfs_create_dir(name, pd);
-	debugfs_create_ulong("frequency", 0444, d, &ps->frequency);
-	debugfs_create_ulong("power", 0444, d, &ps->power);
-	debugfs_create_ulong("cost", 0444, d, &ps->cost);
-	debugfs_create_ulong("inefficient", 0444, d, &ps->flags);
+	debugfs_create_file("frequency", 0444, d, &em_dbg[i],
+			    &em_debug_frequency_fops);
+	debugfs_create_file("power", 0444, d, &em_dbg[i],
+			    &em_debug_power_fops);
+	debugfs_create_file("cost", 0444, d, &em_dbg[i],
+			    &em_debug_cost_fops);
+	debugfs_create_file("performance", 0444, d, &em_dbg[i],
+			    &em_debug_performance_fops);
+	debugfs_create_file("inefficient", 0444, d, &em_dbg[i],
+			    &em_debug_inefficiency_fops);
 }
 
 static int em_debug_cpus_show(struct seq_file *s, void *unused)
@@ -66,6 +118,7 @@ DEFINE_SHOW_ATTRIBUTE(em_debug_flags);
 
 static void em_debug_create_pd(struct device *dev)
 {
+	struct em_dbg_info *em_dbg;
 	struct dentry *d;
 	int i;
 
@@ -79,9 +132,14 @@ static void em_debug_create_pd(struct device *dev)
 	debugfs_create_file("flags", 0444, d, dev->em_pd,
 			    &em_debug_flags_fops);
 
+	em_dbg = devm_kcalloc(dev, dev->em_pd->nr_perf_states,
+			      sizeof(*em_dbg), GFP_KERNEL);
+	if (!em_dbg)
+		return;
+
 	/* Create a sub-directory for each performance state */
 	for (i = 0; i < dev->em_pd->nr_perf_states; i++)
-		em_debug_create_ps(&dev->em_pd->table[i], d);
+		em_debug_create_ps(dev->em_pd, em_dbg, i, d);
 
 }
 
@@ -103,18 +161,192 @@ static void em_debug_create_pd(struct device *dev) {}
 static void em_debug_remove_pd(struct device *dev) {}
 #endif
 
+static void em_destroy_table_rcu(struct rcu_head *rp)
+{
+	struct em_perf_table __rcu *table;
+
+	table = container_of(rp, struct em_perf_table, rcu);
+	kfree(table);
+}
+
+static void em_release_table_kref(struct kref *kref)
+{
+	struct em_perf_table __rcu *table;
+
+	/* It was the last owner of this table so we can free */
+	table = container_of(kref, struct em_perf_table, kref);
+
+	call_rcu(&table->rcu, em_destroy_table_rcu);
+}
+
+/**
+ * em_table_free() - Handles safe free of the EM table when needed
+ * @table : EM table which is going to be freed
+ *
+ * No return values.
+ */
+void em_table_free(struct em_perf_table __rcu *table)
+{
+	kref_put(&table->kref, em_release_table_kref);
+}
+
+/**
+ * em_table_alloc() - Allocate a new EM table
+ * @pd		: EM performance domain for which this must be done
+ *
+ * Allocate a new EM table and initialize its kref to indicate that it
+ * has a user.
+ * Returns allocated table or NULL.
+ */
+struct em_perf_table __rcu *em_table_alloc(struct em_perf_domain *pd)
+{
+	struct em_perf_table __rcu *table;
+	int table_size;
+
+	table_size = sizeof(struct em_perf_state) * pd->nr_perf_states;
+
+	table = kzalloc(sizeof(*table) + table_size, GFP_KERNEL);
+	if (!table)
+		return NULL;
+
+	kref_init(&table->kref);
+
+	return table;
+}
+
+static void em_init_performance(struct device *dev, struct em_perf_domain *pd,
+				struct em_perf_state *table, int nr_states)
+{
+	u64 fmax, max_cap;
+	int i, cpu;
+
+	/* This is needed only for CPUs and EAS skip other devices */
+	if (!_is_cpu_device(dev))
+		return;
+
+	cpu = cpumask_first(em_span_cpus(pd));
+
+	/*
+	 * Calculate the performance value for each frequency with
+	 * linear relationship. The final CPU capacity might not be ready at
+	 * boot time, but the EM will be updated a bit later with correct one.
+	 */
+	fmax = (u64) table[nr_states - 1].frequency;
+	max_cap = (u64) arch_scale_cpu_capacity(cpu);
+	for (i = 0; i < nr_states; i++)
+		table[i].performance = div64_u64(max_cap * table[i].frequency,
+						 fmax);
+}
+
+static int em_compute_costs(struct device *dev, struct em_perf_state *table,
+			    struct em_data_callback *cb, int nr_states,
+			    unsigned long flags)
+{
+	unsigned long prev_cost = ULONG_MAX;
+	int i, ret;
+
+	/* Compute the cost of each performance state. */
+	for (i = nr_states - 1; i >= 0; i--) {
+		unsigned long power_res, cost;
+
+		if ((flags & EM_PERF_DOMAIN_ARTIFICIAL) && cb->get_cost) {
+			ret = cb->get_cost(dev, table[i].frequency, &cost);
+			if (ret || !cost || cost > EM_MAX_POWER) {
+				dev_err(dev, "EM: invalid cost %lu %d\n",
+					cost, ret);
+				return -EINVAL;
+			}
+		} else {
+			/* increase resolution of 'cost' precision */
+			power_res = table[i].power * 10;
+			cost = power_res / table[i].performance;
+		}
+
+		table[i].cost = cost;
+
+		if (table[i].cost >= prev_cost) {
+			table[i].flags = EM_PERF_STATE_INEFFICIENT;
+			dev_dbg(dev, "EM: OPP:%lu is inefficient\n",
+				table[i].frequency);
+		} else {
+			prev_cost = table[i].cost;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * em_dev_compute_costs() - Calculate cost values for new runtime EM table
+ * @dev		: Device for which the EM table is to be updated
+ * @table	: The new EM table that is going to get the costs calculated
+ * @nr_states	: Number of performance states
+ *
+ * Calculate the em_perf_state::cost values for new runtime EM table. The
+ * values are used for EAS during task placement. It also calculates and sets
+ * the efficiency flag for each performance state. When the function finish
+ * successfully the EM table is ready to be updated and used by EAS.
+ *
+ * Return 0 on success or a proper error in case of failure.
+ */
+int em_dev_compute_costs(struct device *dev, struct em_perf_state *table,
+			 int nr_states)
+{
+	return em_compute_costs(dev, table, NULL, nr_states, 0);
+}
+
+/**
+ * em_dev_update_perf_domain() - Update runtime EM table for a device
+ * @dev		: Device for which the EM is to be updated
+ * @new_table	: The new EM table that is going to be used from now
+ *
+ * Update EM runtime modifiable table for the @dev using the provided @table.
+ *
+ * This function uses a mutex to serialize writers, so it must not be called
+ * from a non-sleeping context.
+ *
+ * Return 0 on success or an error code on failure.
+ */
+int em_dev_update_perf_domain(struct device *dev,
+			      struct em_perf_table __rcu *new_table)
+{
+	struct em_perf_table __rcu *old_table;
+	struct em_perf_domain *pd;
+
+	if (!dev)
+		return -EINVAL;
+
+	/* Serialize update/unregister or concurrent updates */
+	mutex_lock(&em_pd_mutex);
+
+	if (!dev->em_pd) {
+		mutex_unlock(&em_pd_mutex);
+		return -EINVAL;
+	}
+	pd = dev->em_pd;
+
+	kref_get(&new_table->kref);
+
+	old_table = pd->em_table;
+	rcu_assign_pointer(pd->em_table, new_table);
+
+	em_cpufreq_update_efficiencies(dev, new_table->state);
+
+	em_table_free(old_table);
+
+	mutex_unlock(&em_pd_mutex);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(em_dev_update_perf_domain);
+
 static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd,
-				int nr_states, struct em_data_callback *cb,
+				struct em_perf_state *table,
+				struct em_data_callback *cb,
 				unsigned long flags)
 {
-	unsigned long power, freq, prev_freq = 0, prev_cost = ULONG_MAX;
-	struct em_perf_state *table;
+	unsigned long power, freq, prev_freq = 0;
+	int nr_states = pd->nr_perf_states;
 	int i, ret;
-	u64 fmax;
-
-	table = kcalloc(nr_states, sizeof(*table), GFP_KERNEL);
-	if (!table)
-		return -ENOMEM;
 
 	/* Build the list of performance states for this performance domain */
 	for (i = 0, freq = 0; i < nr_states; i++, freq++) {
@@ -127,7 +359,7 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd,
 		if (ret) {
 			dev_err(dev, "EM: invalid perf. state: %d\n",
 				ret);
-			goto free_ps_table;
+			return -EINVAL;
 		}
 
 		/*
@@ -137,7 +369,7 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd,
 		if (freq <= prev_freq) {
 			dev_err(dev, "EM: non-increasing freq: %lu\n",
 				freq);
-			goto free_ps_table;
+			return -EINVAL;
 		}
 
 		/*
@@ -147,55 +379,27 @@ static int em_create_perf_table(struct device *dev, struct em_perf_domain *pd,
 		if (!power || power > EM_MAX_POWER) {
 			dev_err(dev, "EM: invalid power: %lu\n",
 				power);
-			goto free_ps_table;
+			return -EINVAL;
 		}
 
 		table[i].power = power;
 		table[i].frequency = prev_freq = freq;
 	}
 
-	/* Compute the cost of each performance state. */
-	fmax = (u64) table[nr_states - 1].frequency;
-	for (i = nr_states - 1; i >= 0; i--) {
-		unsigned long power_res, cost;
-
-		if (flags & EM_PERF_DOMAIN_ARTIFICIAL) {
-			ret = cb->get_cost(dev, table[i].frequency, &cost);
-			if (ret || !cost || cost > EM_MAX_POWER) {
-				dev_err(dev, "EM: invalid cost %lu %d\n",
-					cost, ret);
-				goto free_ps_table;
-			}
-		} else {
-			power_res = table[i].power;
-			cost = div64_u64(fmax * power_res, table[i].frequency);
-		}
-
-		table[i].cost = cost;
-
-		if (table[i].cost >= prev_cost) {
-			table[i].flags = EM_PERF_STATE_INEFFICIENT;
-			dev_dbg(dev, "EM: OPP:%lu is inefficient\n",
-				table[i].frequency);
-		} else {
-			prev_cost = table[i].cost;
-		}
-	}
+	em_init_performance(dev, pd, table, nr_states);
 
-	pd->table = table;
-	pd->nr_perf_states = nr_states;
+	ret = em_compute_costs(dev, table, cb, nr_states, flags);
+	if (ret)
+		return -EINVAL;
 
 	return 0;
-
-free_ps_table:
-	kfree(table);
-	return -EINVAL;
 }
 
 static int em_create_pd(struct device *dev, int nr_states,
 			struct em_data_callback *cb, cpumask_t *cpus,
 			unsigned long flags)
 {
+	struct em_perf_table __rcu *em_table;
 	struct em_perf_domain *pd;
 	struct device *cpu_dev;
 	int cpu, ret, num_cpus;
@@ -220,11 +424,17 @@ static int em_create_pd(struct device *dev, int nr_states,
 			return -ENOMEM;
 	}
 
-	ret = em_create_perf_table(dev, pd, nr_states, cb, flags);
-	if (ret) {
-		kfree(pd);
-		return ret;
-	}
+	pd->nr_perf_states = nr_states;
+
+	em_table = em_table_alloc(pd);
+	if (!em_table)
+		goto free_pd;
+
+	ret = em_create_perf_table(dev, pd, em_table->state, cb, flags);
+	if (ret)
+		goto free_pd_table;
+
+	rcu_assign_pointer(pd->em_table, em_table);
 
 	if (_is_cpu_device(dev))
 		for_each_cpu(cpu, cpus) {
@@ -235,26 +445,37 @@ static int em_create_pd(struct device *dev, int nr_states,
 	dev->em_pd = pd;
 
 	return 0;
+
+free_pd_table:
+	kfree(em_table);
+free_pd:
+	kfree(pd);
+	return -EINVAL;
 }
 
-static void em_cpufreq_update_efficiencies(struct device *dev)
+static void
+em_cpufreq_update_efficiencies(struct device *dev, struct em_perf_state *table)
 {
 	struct em_perf_domain *pd = dev->em_pd;
-	struct em_perf_state *table;
 	struct cpufreq_policy *policy;
 	int found = 0;
-	int i;
+	int i, cpu;
 
-	if (!_is_cpu_device(dev) || !pd)
+	if (!_is_cpu_device(dev))
 		return;
 
-	policy = cpufreq_cpu_get(cpumask_first(em_span_cpus(pd)));
-	if (!policy) {
-		dev_warn(dev, "EM: Access to CPUFreq policy failed");
+	/* Try to get a CPU which is active and in this PD */
+	cpu = cpumask_first_and(em_span_cpus(pd), cpu_active_mask);
+	if (cpu >= nr_cpu_ids) {
+		dev_warn(dev, "EM: No online CPU for CPUFreq policy\n");
 		return;
 	}
 
-	table = pd->table;
+	policy = cpufreq_cpu_get(cpu);
+	if (!policy) {
+		dev_warn(dev, "EM: Access to CPUFreq policy failed\n");
+		return;
+	}
 
 	for (i = 0; i < pd->nr_perf_states; i++) {
 		if (!(table[i].flags & EM_PERF_STATE_INEFFICIENT))
@@ -397,13 +618,17 @@ int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states,
 
 	dev->em_pd->flags |= flags;
 
-	em_cpufreq_update_efficiencies(dev);
+	em_cpufreq_update_efficiencies(dev, dev->em_pd->em_table->state);
 
 	em_debug_create_pd(dev);
 	dev_info(dev, "EM: created perf domain\n");
 
 unlock:
 	mutex_unlock(&em_pd_mutex);
+
+	if (_is_cpu_device(dev))
+		em_check_capacity_update();
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(em_dev_register_perf_domain);
@@ -430,9 +655,125 @@ void em_dev_unregister_perf_domain(struct device *dev)
 	mutex_lock(&em_pd_mutex);
 	em_debug_remove_pd(dev);
 
-	kfree(dev->em_pd->table);
+	em_table_free(dev->em_pd->em_table);
+
 	kfree(dev->em_pd);
 	dev->em_pd = NULL;
 	mutex_unlock(&em_pd_mutex);
 }
 EXPORT_SYMBOL_GPL(em_dev_unregister_perf_domain);
+
+/*
+ * Adjustment of CPU performance values after boot, when all CPUs capacites
+ * are correctly calculated.
+ */
+static void em_adjust_new_capacity(struct device *dev,
+				   struct em_perf_domain *pd,
+				   u64 max_cap)
+{
+	struct em_perf_table __rcu *em_table;
+	struct em_perf_state *ps, *new_ps;
+	int ret, ps_size;
+
+	em_table = em_table_alloc(pd);
+	if (!em_table) {
+		dev_warn(dev, "EM: allocation failed\n");
+		return;
+	}
+
+	new_ps = em_table->state;
+
+	rcu_read_lock();
+	ps = em_perf_state_from_pd(pd);
+	/* Initialize data based on old table */
+	ps_size = sizeof(struct em_perf_state) * pd->nr_perf_states;
+	memcpy(new_ps, ps, ps_size);
+
+	rcu_read_unlock();
+
+	em_init_performance(dev, pd, new_ps, pd->nr_perf_states);
+	ret = em_compute_costs(dev, new_ps, NULL, pd->nr_perf_states,
+			       pd->flags);
+	if (ret) {
+		dev_warn(dev, "EM: compute costs failed\n");
+		return;
+	}
+
+	ret = em_dev_update_perf_domain(dev, em_table);
+	if (ret)
+		dev_warn(dev, "EM: update failed %d\n", ret);
+
+	/*
+	 * This is one-time-update, so give up the ownership in this updater.
+	 * The EM framework has incremented the usage counter and from now
+	 * will keep the reference (then free the memory when needed).
+	 */
+	em_table_free(em_table);
+}
+
+static void em_check_capacity_update(void)
+{
+	cpumask_var_t cpu_done_mask;
+	struct em_perf_state *table;
+	struct em_perf_domain *pd;
+	unsigned long cpu_capacity;
+	int cpu;
+
+	if (!zalloc_cpumask_var(&cpu_done_mask, GFP_KERNEL)) {
+		pr_warn("no free memory\n");
+		return;
+	}
+
+	/* Check if CPUs capacity has changed than update EM */
+	for_each_possible_cpu(cpu) {
+		struct cpufreq_policy *policy;
+		unsigned long em_max_perf;
+		struct device *dev;
+
+		if (cpumask_test_cpu(cpu, cpu_done_mask))
+			continue;
+
+		policy = cpufreq_cpu_get(cpu);
+		if (!policy) {
+			pr_debug("Accessing cpu%d policy failed\n", cpu);
+			schedule_delayed_work(&em_update_work,
+					      msecs_to_jiffies(1000));
+			break;
+		}
+		cpufreq_cpu_put(policy);
+
+		pd = em_cpu_get(cpu);
+		if (!pd || em_is_artificial(pd))
+			continue;
+
+		cpumask_or(cpu_done_mask, cpu_done_mask,
+			   em_span_cpus(pd));
+
+		cpu_capacity = arch_scale_cpu_capacity(cpu);
+
+		rcu_read_lock();
+		table = em_perf_state_from_pd(pd);
+		em_max_perf = table[pd->nr_perf_states - 1].performance;
+		rcu_read_unlock();
+
+		/*
+		 * Check if the CPU capacity has been adjusted during boot
+		 * and trigger the update for new performance values.
+		 */
+		if (em_max_perf == cpu_capacity)
+			continue;
+
+		pr_debug("updating cpu%d cpu_cap=%lu old capacity=%lu\n",
+			 cpu, cpu_capacity, em_max_perf);
+
+		dev = get_cpu_device(cpu);
+		em_adjust_new_capacity(dev, pd, cpu_capacity);
+	}
+
+	free_cpumask_var(cpu_done_mask);
+}
+
+static void em_update_workfn(struct work_struct *work)
+{
+	em_check_capacity_update();
+}
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 4b0b7cf2e019..43b1a82e800c 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -47,6 +47,15 @@ dev_t swsusp_resume_device;
 sector_t swsusp_resume_block;
 __visible int in_suspend __nosavedata;
 
+static char hibernate_compressor[CRYPTO_MAX_ALG_NAME] = CONFIG_HIBERNATION_DEF_COMP;
+
+/*
+ * Compression/decompression algorithm to be used while saving/loading
+ * image to/from disk. This would later be used in 'kernel/power/swap.c'
+ * to allocate comp streams.
+ */
+char hib_comp_algo[CRYPTO_MAX_ALG_NAME];
+
 enum {
 	HIBERNATION_INVALID,
 	HIBERNATION_PLATFORM,
@@ -718,6 +727,9 @@ static int load_image_and_restore(void)
 	return error;
 }
 
+#define COMPRESSION_ALGO_LZO "lzo"
+#define COMPRESSION_ALGO_LZ4 "lz4"
+
 /**
  * hibernate - Carry out system hibernation, including saving the image.
  */
@@ -732,6 +744,17 @@ int hibernate(void)
 		return -EPERM;
 	}
 
+	/*
+	 * Query for the compression algorithm support if compression is enabled.
+	 */
+	if (!nocompress) {
+		strscpy(hib_comp_algo, hibernate_compressor, sizeof(hib_comp_algo));
+		if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
+			pr_err("%s compression is not available\n", hib_comp_algo);
+			return -EOPNOTSUPP;
+		}
+	}
+
 	sleep_flags = lock_system_sleep();
 	/* The snapshot device should not be opened while we're running */
 	if (!hibernate_acquire()) {
@@ -766,11 +789,24 @@ int hibernate(void)
 
 		if (hibernation_mode == HIBERNATION_PLATFORM)
 			flags |= SF_PLATFORM_MODE;
-		if (nocompress)
+		if (nocompress) {
 			flags |= SF_NOCOMPRESS_MODE;
-		else
+		} else {
 		        flags |= SF_CRC32_MODE;
 
+			/*
+			 * By default, LZO compression is enabled. Use SF_COMPRESSION_ALG_LZ4
+			 * to override this behaviour and use LZ4.
+			 *
+			 * Refer kernel/power/power.h for more details
+			 */
+
+			if (!strcmp(hib_comp_algo, COMPRESSION_ALGO_LZ4))
+				flags |= SF_COMPRESSION_ALG_LZ4;
+			else
+				flags |= SF_COMPRESSION_ALG_LZO;
+		}
+
 		pm_pr_dbg("Writing hibernation image.\n");
 		error = swsusp_write(flags);
 		swsusp_free();
@@ -955,6 +991,22 @@ static int software_resume(void)
 	if (error)
 		goto Unlock;
 
+	/*
+	 * Check if the hibernation image is compressed. If so, query for
+	 * the algorithm support.
+	 */
+	if (!(swsusp_header_flags & SF_NOCOMPRESS_MODE)) {
+		if (swsusp_header_flags & SF_COMPRESSION_ALG_LZ4)
+			strscpy(hib_comp_algo, COMPRESSION_ALGO_LZ4, sizeof(hib_comp_algo));
+		else
+			strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO, sizeof(hib_comp_algo));
+		if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) {
+			pr_err("%s compression is not available\n", hib_comp_algo);
+			error = -EOPNOTSUPP;
+			goto Unlock;
+		}
+	}
+
 	/* The snapshot device should not be opened while we're running */
 	if (!hibernate_acquire()) {
 		error = -EBUSY;
@@ -1370,6 +1422,57 @@ static int __init nohibernate_setup(char *str)
 	return 1;
 }
 
+static const char * const comp_alg_enabled[] = {
+#if IS_ENABLED(CONFIG_CRYPTO_LZO)
+	COMPRESSION_ALGO_LZO,
+#endif
+#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
+	COMPRESSION_ALGO_LZ4,
+#endif
+};
+
+static int hibernate_compressor_param_set(const char *compressor,
+		const struct kernel_param *kp)
+{
+	unsigned int sleep_flags;
+	int index, ret;
+
+	sleep_flags = lock_system_sleep();
+
+	index = sysfs_match_string(comp_alg_enabled, compressor);
+	if (index >= 0) {
+		ret = param_set_copystring(comp_alg_enabled[index], kp);
+		if (!ret)
+			strscpy(hib_comp_algo, comp_alg_enabled[index],
+				sizeof(hib_comp_algo));
+	} else {
+		ret = index;
+	}
+
+	unlock_system_sleep(sleep_flags);
+
+	if (ret)
+		pr_debug("Cannot set specified compressor %s\n",
+			 compressor);
+
+	return ret;
+}
+
+static const struct kernel_param_ops hibernate_compressor_param_ops = {
+	.set    = hibernate_compressor_param_set,
+	.get    = param_get_string,
+};
+
+static struct kparam_string hibernate_compressor_param_string = {
+	.maxlen = sizeof(hibernate_compressor),
+	.string = hibernate_compressor,
+};
+
+module_param_cb(compressor, &hibernate_compressor_param_ops,
+		&hibernate_compressor_param_string, 0644);
+MODULE_PARM_DESC(compressor,
+		 "Compression algorithm to be used with hibernation");
+
 __setup("noresume", noresume_setup);
 __setup("resume_offset=", resume_offset_setup);
 __setup("resume=", resume_setup);
diff --git a/kernel/power/main.c b/kernel/power/main.c
index b1ae9b677d03..a9e0693aaf69 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -95,19 +95,6 @@ int unregister_pm_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL_GPL(unregister_pm_notifier);
 
-void pm_report_hw_sleep_time(u64 t)
-{
-	suspend_stats.last_hw_sleep = t;
-	suspend_stats.total_hw_sleep += t;
-}
-EXPORT_SYMBOL_GPL(pm_report_hw_sleep_time);
-
-void pm_report_max_hw_sleep(u64 t)
-{
-	suspend_stats.max_hw_sleep = t;
-}
-EXPORT_SYMBOL_GPL(pm_report_max_hw_sleep);
-
 int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down)
 {
 	int ret;
@@ -319,26 +306,86 @@ static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
 power_attr(pm_test);
 #endif /* CONFIG_PM_SLEEP_DEBUG */
 
-static char *suspend_step_name(enum suspend_stat_step step)
-{
-	switch (step) {
-	case SUSPEND_FREEZE:
-		return "freeze";
-	case SUSPEND_PREPARE:
-		return "prepare";
-	case SUSPEND_SUSPEND:
-		return "suspend";
-	case SUSPEND_SUSPEND_NOIRQ:
-		return "suspend_noirq";
-	case SUSPEND_RESUME_NOIRQ:
-		return "resume_noirq";
-	case SUSPEND_RESUME:
-		return "resume";
-	default:
-		return "";
+#define SUSPEND_NR_STEPS	SUSPEND_RESUME
+#define REC_FAILED_NUM		2
+
+struct suspend_stats {
+	unsigned int step_failures[SUSPEND_NR_STEPS];
+	unsigned int success;
+	unsigned int fail;
+	int last_failed_dev;
+	char failed_devs[REC_FAILED_NUM][40];
+	int last_failed_errno;
+	int errno[REC_FAILED_NUM];
+	int last_failed_step;
+	u64 last_hw_sleep;
+	u64 total_hw_sleep;
+	u64 max_hw_sleep;
+	enum suspend_stat_step failed_steps[REC_FAILED_NUM];
+};
+
+static struct suspend_stats suspend_stats;
+static DEFINE_MUTEX(suspend_stats_lock);
+
+void dpm_save_failed_dev(const char *name)
+{
+	mutex_lock(&suspend_stats_lock);
+
+	strscpy(suspend_stats.failed_devs[suspend_stats.last_failed_dev],
+		name, sizeof(suspend_stats.failed_devs[0]));
+	suspend_stats.last_failed_dev++;
+	suspend_stats.last_failed_dev %= REC_FAILED_NUM;
+
+	mutex_unlock(&suspend_stats_lock);
+}
+
+void dpm_save_failed_step(enum suspend_stat_step step)
+{
+	suspend_stats.step_failures[step-1]++;
+	suspend_stats.failed_steps[suspend_stats.last_failed_step] = step;
+	suspend_stats.last_failed_step++;
+	suspend_stats.last_failed_step %= REC_FAILED_NUM;
+}
+
+void dpm_save_errno(int err)
+{
+	if (!err) {
+		suspend_stats.success++;
+		return;
 	}
+
+	suspend_stats.fail++;
+
+	suspend_stats.errno[suspend_stats.last_failed_errno] = err;
+	suspend_stats.last_failed_errno++;
+	suspend_stats.last_failed_errno %= REC_FAILED_NUM;
 }
 
+void pm_report_hw_sleep_time(u64 t)
+{
+	suspend_stats.last_hw_sleep = t;
+	suspend_stats.total_hw_sleep += t;
+}
+EXPORT_SYMBOL_GPL(pm_report_hw_sleep_time);
+
+void pm_report_max_hw_sleep(u64 t)
+{
+	suspend_stats.max_hw_sleep = t;
+}
+EXPORT_SYMBOL_GPL(pm_report_max_hw_sleep);
+
+static const char * const suspend_step_names[] = {
+	[SUSPEND_WORKING] = "",
+	[SUSPEND_FREEZE] = "freeze",
+	[SUSPEND_PREPARE] = "prepare",
+	[SUSPEND_SUSPEND] = "suspend",
+	[SUSPEND_SUSPEND_LATE] = "suspend_late",
+	[SUSPEND_SUSPEND_NOIRQ] = "suspend_noirq",
+	[SUSPEND_RESUME_NOIRQ] = "resume_noirq",
+	[SUSPEND_RESUME_EARLY] = "resume_early",
+	[SUSPEND_RESUME] = "resume",
+};
+
 #define suspend_attr(_name, format_str)				\
 static ssize_t _name##_show(struct kobject *kobj,		\
 		struct kobj_attribute *attr, char *buf)		\
@@ -347,20 +394,30 @@ static ssize_t _name##_show(struct kobject *kobj,		\
 }								\
 static struct kobj_attribute _name = __ATTR_RO(_name)
 
-suspend_attr(success, "%d\n");
-suspend_attr(fail, "%d\n");
-suspend_attr(failed_freeze, "%d\n");
-suspend_attr(failed_prepare, "%d\n");
-suspend_attr(failed_suspend, "%d\n");
-suspend_attr(failed_suspend_late, "%d\n");
-suspend_attr(failed_suspend_noirq, "%d\n");
-suspend_attr(failed_resume, "%d\n");
-suspend_attr(failed_resume_early, "%d\n");
-suspend_attr(failed_resume_noirq, "%d\n");
+suspend_attr(success, "%u\n");
+suspend_attr(fail, "%u\n");
 suspend_attr(last_hw_sleep, "%llu\n");
 suspend_attr(total_hw_sleep, "%llu\n");
 suspend_attr(max_hw_sleep, "%llu\n");
 
+#define suspend_step_attr(_name, step)		\
+static ssize_t _name##_show(struct kobject *kobj,		\
+		struct kobj_attribute *attr, char *buf)		\
+{								\
+	return sprintf(buf, "%u\n",				\
+		       suspend_stats.step_failures[step-1]);	\
+}								\
+static struct kobj_attribute _name = __ATTR_RO(_name)
+
+suspend_step_attr(failed_freeze, SUSPEND_FREEZE);
+suspend_step_attr(failed_prepare, SUSPEND_PREPARE);
+suspend_step_attr(failed_suspend, SUSPEND_SUSPEND);
+suspend_step_attr(failed_suspend_late, SUSPEND_SUSPEND_LATE);
+suspend_step_attr(failed_suspend_noirq, SUSPEND_SUSPEND_NOIRQ);
+suspend_step_attr(failed_resume, SUSPEND_RESUME);
+suspend_step_attr(failed_resume_early, SUSPEND_RESUME_EARLY);
+suspend_step_attr(failed_resume_noirq, SUSPEND_RESUME_NOIRQ);
+
 static ssize_t last_failed_dev_show(struct kobject *kobj,
 		struct kobj_attribute *attr, char *buf)
 {
@@ -392,16 +449,14 @@ static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
 static ssize_t last_failed_step_show(struct kobject *kobj,
 		struct kobj_attribute *attr, char *buf)
 {
-	int index;
 	enum suspend_stat_step step;
-	char *last_failed_step = NULL;
+	int index;
 
 	index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
 	index %= REC_FAILED_NUM;
 	step = suspend_stats.failed_steps[index];
-	last_failed_step = suspend_step_name(step);
 
-	return sprintf(buf, "%s\n", last_failed_step);
+	return sprintf(buf, "%s\n", suspend_step_names[step]);
 }
 static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
 
@@ -449,6 +504,7 @@ static const struct attribute_group suspend_attr_group = {
 static int suspend_stats_show(struct seq_file *s, void *unused)
 {
 	int i, index, last_dev, last_errno, last_step;
+	enum suspend_stat_step step;
 
 	last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
 	last_dev %= REC_FAILED_NUM;
@@ -456,47 +512,35 @@ static int suspend_stats_show(struct seq_file *s, void *unused)
 	last_errno %= REC_FAILED_NUM;
 	last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
 	last_step %= REC_FAILED_NUM;
-	seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
-			"%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
-			"success", suspend_stats.success,
-			"fail", suspend_stats.fail,
-			"failed_freeze", suspend_stats.failed_freeze,
-			"failed_prepare", suspend_stats.failed_prepare,
-			"failed_suspend", suspend_stats.failed_suspend,
-			"failed_suspend_late",
-				suspend_stats.failed_suspend_late,
-			"failed_suspend_noirq",
-				suspend_stats.failed_suspend_noirq,
-			"failed_resume", suspend_stats.failed_resume,
-			"failed_resume_early",
-				suspend_stats.failed_resume_early,
-			"failed_resume_noirq",
-				suspend_stats.failed_resume_noirq);
+
+	seq_printf(s, "success: %u\nfail: %u\n",
+		   suspend_stats.success, suspend_stats.fail);
+
+	for (step = SUSPEND_FREEZE; step <= SUSPEND_NR_STEPS; step++)
+		seq_printf(s, "failed_%s: %u\n", suspend_step_names[step],
+			   suspend_stats.step_failures[step-1]);
+
 	seq_printf(s,	"failures:\n  last_failed_dev:\t%-s\n",
-			suspend_stats.failed_devs[last_dev]);
+		   suspend_stats.failed_devs[last_dev]);
 	for (i = 1; i < REC_FAILED_NUM; i++) {
 		index = last_dev + REC_FAILED_NUM - i;
 		index %= REC_FAILED_NUM;
-		seq_printf(s, "\t\t\t%-s\n",
-			suspend_stats.failed_devs[index]);
+		seq_printf(s, "\t\t\t%-s\n", suspend_stats.failed_devs[index]);
 	}
 	seq_printf(s,	"  last_failed_errno:\t%-d\n",
 			suspend_stats.errno[last_errno]);
 	for (i = 1; i < REC_FAILED_NUM; i++) {
 		index = last_errno + REC_FAILED_NUM - i;
 		index %= REC_FAILED_NUM;
-		seq_printf(s, "\t\t\t%-d\n",
-			suspend_stats.errno[index]);
+		seq_printf(s, "\t\t\t%-d\n", suspend_stats.errno[index]);
 	}
 	seq_printf(s,	"  last_failed_step:\t%-s\n",
-			suspend_step_name(
-				suspend_stats.failed_steps[last_step]));
+		   suspend_step_names[suspend_stats.failed_steps[last_step]]);
 	for (i = 1; i < REC_FAILED_NUM; i++) {
 		index = last_step + REC_FAILED_NUM - i;
 		index %= REC_FAILED_NUM;
 		seq_printf(s, "\t\t\t%-s\n",
-			suspend_step_name(
-				suspend_stats.failed_steps[index]));
+			   suspend_step_names[suspend_stats.failed_steps[index]]);
 	}
 
 	return 0;
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 8499a39c62f4..de0e6b1077f2 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -6,6 +6,7 @@
 #include <linux/compiler.h>
 #include <linux/cpu.h>
 #include <linux/cpuidle.h>
+#include <linux/crypto.h>
 
 struct swsusp_info {
 	struct new_utsname	uts;
@@ -54,6 +55,10 @@ asmlinkage int swsusp_save(void);
 
 /* kernel/power/hibernate.c */
 extern bool freezer_test_done;
+extern char hib_comp_algo[CRYPTO_MAX_ALG_NAME];