From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Mon, 2 Apr 2018 23:50:39 +0000 (-0700)
Subject: Merge branch 'sched-wait-for-linus' of git://git.kernel.org/pub/scm/linux/kernel... 
X-Git-Tag: v4.17-rc1~168
X-Git-Url: https://repo.jachan.dev/linux.git/commitdiff_plain/ce6eba3dba366b607c0a363c7cdbd4ee8fcc6434?hp=-c

Merge branch 'sched-wait-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull wait_var_event updates from Ingo Molnar:
 "This introduces the new wait_var_event() API, which is a more flexible
  waiting primitive than wait_on_atomic_t().

  All wait_on_atomic_t() users are migrated over to the new API and
  wait_on_atomic_t() is removed. The migration fixes one bug and should
  result in no functional changes for the other usecases"

* 'sched-wait-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/wait: Improve __var_waitqueue() code generation
  sched/wait: Remove the wait_on_atomic_t() API
  sched/wait, arch/mips: Fix and convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/ocfs2: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/fscache: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/btrfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, fs/afs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, drivers/media: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait, drivers/drm: Convert wait_on_atomic_t() usage to the new wait_var_event() API
  sched/wait: Introduce wait_var_event()
---

ce6eba3dba366b607c0a363c7cdbd4ee8fcc6434
diff --combined fs/nfs/write.c
index e7d8ceae8f26,fd805771ea2f..6579f3b367bd
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@@ -1620,8 -1620,8 +1620,8 @@@ static void nfs_writeback_result(struc
  
  static int wait_on_commit(struct nfs_mds_commit_info *cinfo)
  {
- 	return wait_on_atomic_t(&cinfo->rpcs_out,
- 			nfs_wait_atomic_killable, TASK_KILLABLE);
+ 	return wait_var_event_killable(&cinfo->rpcs_out,
+ 				       !atomic_read(&cinfo->rpcs_out));
  }
  
  static void nfs_commit_begin(struct nfs_mds_commit_info *cinfo)
@@@ -1632,7 -1632,7 +1632,7 @@@
  static void nfs_commit_end(struct nfs_mds_commit_info *cinfo)
  {
  	if (atomic_dec_and_test(&cinfo->rpcs_out))
- 		wake_up_atomic_t(&cinfo->rpcs_out);
+ 		wake_up_var(&cinfo->rpcs_out);
  }
  
  void nfs_commitdata_release(struct nfs_commit_data *data)
@@@ -1876,43 -1876,40 +1876,43 @@@ int nfs_generic_commit_list(struct inod
  	return status;
  }
  
 -int nfs_commit_inode(struct inode *inode, int how)
 +static int __nfs_commit_inode(struct inode *inode, int how,
 +		struct writeback_control *wbc)
  {
  	LIST_HEAD(head);
  	struct nfs_commit_info cinfo;
  	int may_wait = how & FLUSH_SYNC;
 -	int error = 0;
 -	int res;
 +	int ret, nscan;
  
  	nfs_init_cinfo_from_inode(&cinfo, inode);
  	nfs_commit_begin(cinfo.mds);
 -	res = nfs_scan_commit(inode, &head, &cinfo);
 -	if (res)
 -		error = nfs_generic_commit_list(inode, &head, how, &cinfo);
 +	for (;;) {
 +		ret = nscan = nfs_scan_commit(inode, &head, &cinfo);
 +		if (ret <= 0)
 +			break;
 +		ret = nfs_generic_commit_list(inode, &head, how, &cinfo);
 +		if (ret < 0)
 +			break;
 +		ret = 0;
 +		if (wbc && wbc->sync_mode == WB_SYNC_NONE) {
 +			if (nscan < wbc->nr_to_write)
 +				wbc->nr_to_write -= nscan;
 +			else
 +				wbc->nr_to_write = 0;
 +		}
 +		if (nscan < INT_MAX)
 +			break;
 +		cond_resched();
 +	}
  	nfs_commit_end(cinfo.mds);
 -	if (res == 0)
 -		return res;
 -	if (error < 0)
 -		goto out_error;
 -	if (!may_wait)
 -		goto out_mark_dirty;
 -	error = wait_on_commit(cinfo.mds);
 -	if (error < 0)
 -		return error;
 -	return res;
 -out_error:
 -	res = error;
 -	/* Note: If we exit without ensuring that the commit is complete,
 -	 * we must mark the inode as dirty. Otherwise, future calls to
 -	 * sync_inode() with the WB_SYNC_ALL flag set will fail to ensure
 -	 * that the data is on the disk.
 -	 */
 -out_mark_dirty:
 -	__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
 -	return res;
 +	if (ret || !may_wait)
 +		return ret;
 +	return wait_on_commit(cinfo.mds);
 +}
 +
 +int nfs_commit_inode(struct inode *inode, int how)
 +{
 +	return __nfs_commit_inode(inode, how, NULL);
  }
  EXPORT_SYMBOL_GPL(nfs_commit_inode);
  
@@@ -1922,11 -1919,11 +1922,11 @@@ int nfs_write_inode(struct inode *inode
  	int flags = FLUSH_SYNC;
  	int ret = 0;
  
 -	/* no commits means nothing needs to be done */
 -	if (!atomic_long_read(&nfsi->commit_info.ncommit))
 -		return ret;
 -
  	if (wbc->sync_mode == WB_SYNC_NONE) {
 +		/* no commits means nothing needs to be done */
 +		if (!atomic_long_read(&nfsi->commit_info.ncommit))
 +			goto check_requests_outstanding;
 +
  		/* Don't commit yet if this is a non-blocking flush and there
  		 * are a lot of outstanding writes for this mapping.
  		 */
@@@ -1937,16 -1934,16 +1937,16 @@@
  		flags = 0;
  	}
  
 -	ret = nfs_commit_inode(inode, flags);
 -	if (ret >= 0) {
 -		if (wbc->sync_mode == WB_SYNC_NONE) {
 -			if (ret < wbc->nr_to_write)
 -				wbc->nr_to_write -= ret;
 -			else
 -				wbc->nr_to_write = 0;
 -		}
 -		return 0;
 -	}
 +	ret = __nfs_commit_inode(inode, flags, wbc);
 +	if (!ret) {
 +		if (flags & FLUSH_SYNC)
 +			return 0;
 +	} else if (atomic_long_read(&nfsi->commit_info.ncommit))
 +		goto out_mark_dirty;
 +
 +check_requests_outstanding:
 +	if (!atomic_read(&nfsi->commit_info.rpcs_out))
 +		return ret;
  out_mark_dirty:
  	__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
  	return ret;