From 40198cf1716155f25cc8c78579e966da955dceeb Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@sgi.com>
Date: Mon, 7 Apr 2003 23:36:15 +0200
Subject: [PATCH] [XFS] remove atomicIncWithWrap

SGI Modid: 2.5.x-xfs:slinx:143647a
---
 fs/xfs/linux/xfs_globals.c |  5 -----
 fs/xfs/linux/xfs_globals.h |  4 ----
 fs/xfs/support/ktrace.c    |  8 ++++++--
 fs/xfs/xfs.h               |  1 -
 fs/xfs/xfs_ialloc.c        | 19 +++++++++++++++++--
 fs/xfs/xfs_mount.c         |  1 +
 fs/xfs/xfs_mount.h         |  1 +
 7 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/fs/xfs/linux/xfs_globals.c b/fs/xfs/linux/xfs_globals.c
index 21ac11aecd993..da5d0fe00b630 100644
--- a/fs/xfs/linux/xfs_globals.c
+++ b/fs/xfs/linux/xfs_globals.c
@@ -48,11 +48,6 @@ unsigned long xfs_physmem;
  */
 xfs_param_t xfs_params = { 0, 1, 0, 0, 0, 3 };
 
-/*
- * Used to serialize atomicIncWithWrap.
- */
-spinlock_t xfs_atomic_spin = SPIN_LOCK_UNLOCKED;
-
 /*
  * Global system credential structure.
  */
diff --git a/fs/xfs/linux/xfs_globals.h b/fs/xfs/linux/xfs_globals.h
index 190e0717617ce..42d9f3ac180aa 100644
--- a/fs/xfs/linux/xfs_globals.h
+++ b/fs/xfs/linux/xfs_globals.h
@@ -38,11 +38,7 @@
  */
 
 extern uint64_t xfs_panic_mask;		/* set to cause more panics */
-
 extern unsigned long xfs_physmem;
-
-extern spinlock_t xfs_atomic_spin;
-
 extern struct cred *sys_cred;
 
 #endif	/* __XFS_GLOBALS_H__ */
diff --git a/fs/xfs/support/ktrace.c b/fs/xfs/support/ktrace.c
index 99743764a5033..35fdea9d0305d 100644
--- a/fs/xfs/support/ktrace.c
+++ b/fs/xfs/support/ktrace.c
@@ -37,7 +37,6 @@
 #include "kmem.h"
 #include "spin.h"
 #include "debug.h"
-#include "atomic.h"
 #include "ktrace.h"
 
 #if	(defined(DEBUG) || defined(CONFIG_XFS_VNODE_TRACING))
@@ -181,6 +180,7 @@ ktrace_enter(
 	void		*val14,
 	void		*val15)
 {
+	static lock_t   wrap_lock = SPIN_LOCK_UNLOCKED;
 	int		index;
 	ktrace_entry_t	*ktep;
 
@@ -189,7 +189,11 @@ ktrace_enter(
 	/*
 	 * Grab an entry by pushing the index up to the next one.
 	 */
-	index = atomicIncWithWrap(&ktp->kt_index, ktp->kt_nentries);
+	spin_lock(&wrap_lock);
+	index = ktp->kt_index;
+	if (++ktp->kt_index == ktp->kt_nentries)
+		ktp->kt_index = 0;
+	spin_unlock(&wrap_lock);
 
 	if (!ktp->kt_rollover && index == ktp->kt_nentries - 1)
 		ktp->kt_rollover = 1;
diff --git a/fs/xfs/xfs.h b/fs/xfs/xfs.h
index 0c869d102fd0b..5b9cbb8b50268 100644
--- a/fs/xfs/xfs.h
+++ b/fs/xfs/xfs.h
@@ -46,7 +46,6 @@
 #include <support/ktrace.h>
 #include <support/mutex.h>
 #include <support/sema.h>
-#include <support/atomic.h>
 #include <support/debug.h>
 #include <support/move.h>
 #include <support/uuid.h>
diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c
index ff6f1d982b9cd..405f2e7132fe5 100644
--- a/fs/xfs/xfs_ialloc.c
+++ b/fs/xfs/xfs_ialloc.c
@@ -336,6 +336,21 @@ xfs_ialloc_ag_alloc(
 	return 0;
 }
 
+STATIC __inline xfs_agnumber_t
+xfs_ialloc_next_ag(
+	xfs_mount_t	*mp)
+{
+	xfs_agnumber_t	agno;
+
+	spin_lock(&mp->m_agirotor_lock);
+	agno = mp->m_agirotor;
+	if (++mp->m_agirotor == mp->m_maxagi)
+		mp->m_agirotor = 0;
+	spin_unlock(&mp->m_agirotor_lock);
+
+	return agno;
+}
+
 /*
  * Select an allocation group to look for a free inode in, based on the parent
  * inode and then mode.	 Return the allocation group buffer.
@@ -366,7 +381,7 @@ xfs_ialloc_ag_select(
 	mp = tp->t_mountp;
 	agcount = mp->m_maxagi;
 	if (S_ISDIR(mode))
-		pagno = atomicIncWithWrap((int *)&mp->m_agirotor, agcount);
+		pagno = xfs_ialloc_next_ag(mp);
 	else {
 		pagno = XFS_INO_TO_AGNO(mp, parent);
 		if (pagno >= agcount)
@@ -394,7 +409,7 @@ xfs_ialloc_ag_select(
 			agbp = NULL;
 
 		if (!pag->pagi_inodeok) {
-			atomicIncWithWrap((int *)&mp->m_agirotor, agcount);
+			xfs_ialloc_next_ag(mp);
 			goto unlock_nextag;
 		}
 
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index c3f64fb7711f4..22d497b2b898f 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -509,6 +509,7 @@ xfs_mount_common(xfs_mount_t *mp, xfs_sb_t *sbp)
 	int	i;
 
 	mp->m_agfrotor = mp->m_agirotor = 0;
+	spinlock_init(&mp->m_agirotor_lock, "m_agirotor_lock");
 	mp->m_maxagi = mp->m_sb.sb_agcount;
 	mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
 	mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 62f598e4d5333..ca274d6e242fb 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -291,6 +291,7 @@ typedef struct xfs_mount {
 	int			m_bsize;	/* fs logical block size */
 	xfs_agnumber_t		m_agfrotor;	/* last ag where space found */
 	xfs_agnumber_t		m_agirotor;	/* last ag dir inode alloced */
+	lock_t			m_agirotor_lock;/* .. and lock protecting it */
 	xfs_agnumber_t		m_maxagi;	/* highest inode alloc group */
 	int			m_ihsize;	/* size of next field */
 	struct xfs_ihash	*m_ihash;	/* fs private inode hash table*/
-- 
2.53.0