mm: replace all open encodings for NUMA_NO_NODE

Patch series "Replace all open encodings for NUMA_NO_NODE", v3.

All these places for replacement were found by running the following
grep patterns on the entire kernel code.  Please let me know if this
might have missed some instances.  This might also have replaced some
false positives.  I will appreciate suggestions, inputs and review.

1. git grep "nid == -1"
2. git grep "node == -1"
3. git grep "nid = -1"
4. git grep "node = -1"

This patch (of 2):

At present there are multiple places where invalid node number is
encoded as -1.  Even though implicitly understood it is always better to
have macros in there.  Replace these open encodings for an invalid node
number with the global macro NUMA_NO_NODE.  This helps remove NUMA
related assumptions like 'invalid node' from various places redirecting
them to a common definition.

Link: http://lkml.kernel.org/r/1545127933-10711-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>	[ixgbe]
Acked-by: Jens Axboe <axboe@kernel.dk>			[mtip32xx]
Acked-by: Vinod Koul <vkoul@kernel.org>			[dmaengine.c]
Acked-by: Michael Ellerman <mpe@ellerman.id.au>		[powerpc]
Acked-by: Doug Ledford <dledford@redhat.com>		[drivers/infiniband]
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 10 insertions, 8 deletions

diff --git a/kernel/kthread.c b/kernel/kthread.c
index 087d18d771b5..ebebbcf3c5de 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -20,6 +20,7 @@
 #include <linux/freezer.h>
 #include <linux/ptrace.h>
 #include <linux/uaccess.h>
+#include <linux/numa.h>
 #include <trace/events/sched.h>
 
 static DEFINE_SPINLOCK(kthread_create_lock);
@@ -675,7 +676,7 @@ __kthread_create_worker(int cpu, unsigned int flags,
 {
 	struct kthread_worker *worker;
 	struct task_struct *task;
-	int node = -1;
+	int node = NUMA_NO_NODE;
 
 	worker = kzalloc(sizeof(*worker), GFP_KERNEL);
 	if (!worker)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 310d0637fe4b..0e6a0ef129c5 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1160,7 +1160,7 @@ void init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
 
 	/* New address space, reset the preferred nid */
 	if (!(clone_flags & CLONE_VM)) {
-		p->numa_preferred_nid = -1;
+		p->numa_preferred_nid = NUMA_NO_NODE;
 		return;
 	}
 
@@ -1180,13 +1180,13 @@ void init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
 
 static void account_numa_enqueue(struct rq *rq, struct task_struct *p)
 {
-	rq->nr_numa_running += (p->numa_preferred_nid != -1);
+	rq->nr_numa_running += (p->numa_preferred_nid != NUMA_NO_NODE);
 	rq->nr_preferred_running += (p->numa_preferred_nid == task_node(p));
 }
 
 static void account_numa_dequeue(struct rq *rq, struct task_struct *p)
 {
-	rq->nr_numa_running -= (p->numa_preferred_nid != -1);
+	rq->nr_numa_running -= (p->numa_preferred_nid != NUMA_NO_NODE);
 	rq->nr_preferred_running -= (p->numa_preferred_nid == task_node(p));
 }
 
@@ -1400,7 +1400,7 @@ bool should_numa_migrate_memory(struct task_struct *p, struct page * page,
 	 * two full passes of the "multi-stage node selection" test that is
 	 * executed below.
 	 */
-	if ((p->numa_preferred_nid == -1 || p->numa_scan_seq <= 4) &&
+	if ((p->numa_preferred_nid == NUMA_NO_NODE || p->numa_scan_seq <= 4) &&
 	    (cpupid_pid_unset(last_cpupid) || cpupid_match_pid(p, last_cpupid)))
 		return true;
 
@@ -1848,7 +1848,7 @@ static void numa_migrate_preferred(struct task_struct *p)
 	unsigned long interval = HZ;
 
 	/* This task has no NUMA fault statistics yet */
-	if (unlikely(p->numa_preferred_nid == -1 || !p->numa_faults))
+	if (unlikely(p->numa_preferred_nid == NUMA_NO_NODE || !p->numa_faults))
 		return;
 
 	/* Periodically retry migrating the task to the preferred node */
@@ -2095,7 +2095,7 @@ static int preferred_group_nid(struct task_struct *p, int nid)
 
 static void task_numa_placement(struct task_struct *p)
 {
-	int seq, nid, max_nid = -1;
+	int seq, nid, max_nid = NUMA_NO_NODE;
 	unsigned long max_faults = 0;
 	unsigned long fault_types[2] = { 0, 0 };
 	unsigned long total_faults;
@@ -2638,7 +2638,8 @@ static void update_scan_period(struct task_struct *p, int new_cpu)
 		 * the preferred node.
 		 */
 		if (dst_nid == p->numa_preferred_nid ||
-		    (p->numa_preferred_nid != -1 && src_nid != p->numa_preferred_nid))
+		    (p->numa_preferred_nid != NUMA_NO_NODE &&
+			src_nid != p->numa_preferred_nid))
 			return;
 	}