core kernel fixes

index adb5e5a..854dc4c 100644
@@ -87,8 +87,9 @@ static inline void kfree_call_rcu(struct rcu_head *head,
 
 #ifdef CONFIG_TINY_RCU
 
-static inline int rcu_needs_cpu(int cpu)
+static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
 {
+	*delta_jiffies = ULONG_MAX;
 	return 0;
 }
 

@@ -96,8 +97,9 @@ static inline int rcu_needs_cpu(int cpu)
 
 int rcu_preempt_needs_cpu(void);
 
-static inline int rcu_needs_cpu(int cpu)
+static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
 {
+	*delta_jiffies = ULONG_MAX;
 	return rcu_preempt_needs_cpu();
 }
 

index 3c6083c..952b793 100644
@@ -32,7 +32,7 @@
 
 extern void rcu_init(void);
 extern void rcu_note_context_switch(int cpu);
-extern int rcu_needs_cpu(int cpu);
+extern int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies);
 extern void rcu_cpu_stall_reset(void);
 
 /*

index 1480900..d274734 100644
@@ -289,6 +289,7 @@ TRACE_EVENT(rcu_dyntick,
  *	"In holdoff": Nothing to do, holding off after unsuccessful attempt.
  *	"Begin holdoff": Attempt failed, don't retry until next jiffy.
  *	"Dyntick with callbacks": Entering dyntick-idle despite callbacks.
+ *	"Dyntick with lazy callbacks": Entering dyntick-idle w/lazy callbacks.
  *	"More callbacks": Still more callbacks, try again to clear them out.
  *	"Callbacks drained": All callbacks processed, off to dyntick idle!
  *	"Timer": Timer fired to cause CPU to continue processing callbacks.

index 8ed89a1..d2a5f4e 100644
@@ -27,7 +27,7 @@
 #define PANIC_TIMER_STEP 100
 #define PANIC_BLINK_SPD 18
 
-int panic_on_oops;
+int panic_on_oops = CONFIG_PANIC_ON_OOPS_VALUE;
 static unsigned long tainted_mask;
 static int pause_on_oops;
 static int pause_on_oops_flag;

@@ -108,8 +108,6 @@ void panic(const char *fmt, ...)
 	 */
 	crash_kexec(NULL);
 
-	kmsg_dump(KMSG_DUMP_PANIC);
-
 	/*
 	 * Note smp_send_stop is the usual smp shutdown function, which
 	 * unfortunately means it may not be hardened to work in a panic

@@ -117,6 +115,8 @@ void panic(const char *fmt, ...)
 	 */
 	smp_send_stop();
 
+	kmsg_dump(KMSG_DUMP_PANIC);
+
 	atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
 
 	bust_spinlocks(0);

index 0da7b88..3b0f133 100644
@@ -1397,6 +1397,8 @@ static void rcu_adopt_orphan_cbs(struct rcu_state *rsp)
 	rdp->qlen_lazy += rsp->qlen_lazy;
 	rdp->qlen += rsp->qlen;
 	rdp->n_cbs_adopted += rsp->qlen;
+	if (rsp->qlen_lazy != rsp->qlen)
+		rcu_idle_count_callbacks_posted();
 	rsp->qlen_lazy = 0;
 	rsp->qlen = 0;
 

index 7f5d138..ea05649 100644
@@ -84,6 +84,20 @@ struct rcu_dynticks {
 				    /* Process level is worth LLONG_MAX/2. */
 	int dynticks_nmi_nesting;   /* Track NMI nesting level. */
 	atomic_t dynticks;	    /* Even value for idle, else odd. */
+#ifdef CONFIG_RCU_FAST_NO_HZ
+	int dyntick_drain;	    /* Prepare-for-idle state variable. */
+	unsigned long dyntick_holdoff;
+				    /* No retries for the jiffy of failure. */
+	struct timer_list idle_gp_timer;
+				    /* Wake up CPU sleeping with callbacks. */
+	unsigned long idle_gp_timer_expires;
+				    /* When to wake up CPU (for repost). */
+	bool idle_first_pass;	    /* First pass of attempt to go idle? */
+	unsigned long nonlazy_posted;
+				    /* # times non-lazy CBs posted to CPU. */
+	unsigned long nonlazy_posted_snap;
+				    /* idle-period nonlazy_posted snapshot. */
+#endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
 };
 
 /* RCU's kthread states for tracing. */

260 lines not on this page · raw message

index da70c6d..8699978 100644
@@ -274,6 +274,7 @@ EXPORT_SYMBOL_GPL(get_cpu_iowait_time_us);
 static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
 {
 	unsigned long seq, last_jiffies, next_jiffies, delta_jiffies;
+	unsigned long rcu_delta_jiffies;
 	ktime_t last_update, expires, now;
 	struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev;
 	u64 time_delta;

@@ -322,7 +323,7 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
 		time_delta = timekeeping_max_deferment();
 	} while (read_seqretry(&xtime_lock, seq));
 
-	if (rcu_needs_cpu(cpu) || printk_needs_cpu(cpu) ||
+	if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) || printk_needs_cpu(cpu) ||
 	    arch_needs_cpu(cpu)) {
 		next_jiffies = last_jiffies + 1;
 		delta_jiffies = 1;

@@ -330,6 +331,10 @@ static void tick_nohz_stop_sched_tick(struct tick_sched *ts)
 		/* Get the next timer wheel timer */
 		next_jiffies = get_next_timer_interrupt(last_jiffies);
 		delta_jiffies = next_jiffies - last_jiffies;
+		if (rcu_delta_jiffies < delta_jiffies) {
+			next_jiffies = last_jiffies + rcu_delta_jiffies;
+			delta_jiffies = rcu_delta_jiffies;
+		}
 	}
 	/*
 	 * Do not stop the tick, if we are only one off

index d0ec4f3..e91fbc2 100644
@@ -118,7 +118,7 @@ static void __spin_lock_debug(raw_spinlock_t *lock)
 		/* lockup suspected: */
 		if (print_once) {
 			print_once = 0;
-			spin_dump(lock, "lockup");
+			spin_dump(lock, "lockup suspected");
 #ifdef CONFIG_SMP
 			trigger_all_cpu_backtrace();
 #endif

index 952123e..32a0a5e 100644
@@ -867,6 +867,16 @@ int __init_memblock memblock_is_memory(phys_addr_t addr)
 	return memblock_search(&memblock.memory, addr) != -1;
 }
 
+/**
+ * memblock_is_region_memory - check if a region is a subset of memory
+ * @base: base of region to check
+ * @size: size of region to check
+ *
+ * Check if the region [@base, @base+@size) is a subset of a memory block.
+ *
+ * RETURNS:
+ * 0 if false, non-zero if true
+ */
 int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
 {
 	int idx = memblock_search(&memblock.memory, base);

@@ -879,6 +889,16 @@ int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size
 		 memblock.memory.regions[idx].size) >= end;
 }
 
+/**
+ * memblock_is_region_reserved - check if a region intersects reserved memory
+ * @base: base of region to check
+ * @size: size of region to check
+ *
+ * Check if the region [@base, @base+@size) intersects a reserved memory block.
+ *
+ * RETURNS:
+ * 0 if false, non-zero if true
+ */
 int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
 {
 	memblock_cap_size(base, &size);