diff mbox series

[v5,1/2] ceph: add a dedicated private data for netfs rreq

Message ID 20230511030335.337094-2-xiubli@redhat.com (mailing list archive)
State New, archived
Headers show
Series ceph: fix blindly expanding the readahead windows | expand

Commit Message

Xiubo Li May 11, 2023, 3:03 a.m. UTC
From: Xiubo Li <xiubli@redhat.com>

We need to save the 'f_ra.ra_pages' to expand the readahead window
later.

Cc: stable@vger.kernel.org
Fixes: 49870056005c ("ceph: convert ceph_readpages to ceph_readahead")
URL: https://lore.kernel.org/ceph-devel/20230504082510.247-1-sehuww@mail.scut.edu.cn
URL: https://www.spinics.net/lists/ceph-users/msg76183.html
Cc: Hu Weiwen <sehuww@mail.scut.edu.cn>
Signed-off-by: Xiubo Li <xiubli@redhat.com>
---
 fs/ceph/addr.c  | 43 ++++++++++++++++++++++++++++++++-----------
 fs/ceph/super.h | 13 +++++++++++++
 2 files changed, 45 insertions(+), 11 deletions(-)

Comments

胡玮文 May 12, 2023, 2:13 p.m. UTC | #1
On Thu, May 11, 2023 at 11:03:34AM +0800, xiubli@redhat.com wrote:
> From: Xiubo Li <xiubli@redhat.com>
> 
> We need to save the 'f_ra.ra_pages' to expand the readahead window
> later.
> 
> Cc: stable@vger.kernel.org
> Fixes: 49870056005c ("ceph: convert ceph_readpages to ceph_readahead")
> URL: https://lore.kernel.org/ceph-devel/20230504082510.247-1-sehuww@mail.scut.edu.cn
> URL: https://www.spinics.net/lists/ceph-users/msg76183.html
> Cc: Hu Weiwen <sehuww@mail.scut.edu.cn>
> Signed-off-by: Xiubo Li <xiubli@redhat.com>
> ---
>  fs/ceph/addr.c  | 43 ++++++++++++++++++++++++++++++++-----------
>  fs/ceph/super.h | 13 +++++++++++++
>  2 files changed, 45 insertions(+), 11 deletions(-)
> 
> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
> index 3b20873733af..db55fce13324 100644
> --- a/fs/ceph/addr.c
> +++ b/fs/ceph/addr.c
> @@ -404,18 +404,27 @@ static int ceph_init_request(struct netfs_io_request *rreq, struct file *file)
>  {
>  	struct inode *inode = rreq->inode;
>  	int got = 0, want = CEPH_CAP_FILE_CACHE;
> +	struct ceph_netfs_request_data *priv;
>  	int ret = 0;
>  
>  	if (rreq->origin != NETFS_READAHEAD)
>  		return 0;
>  
> +	priv = kzalloc(sizeof(*priv), GFP_NOFS);
> +	if (!priv)
> +		return -ENOMEM;
> +
>  	if (file) {
>  		struct ceph_rw_context *rw_ctx;
>  		struct ceph_file_info *fi = file->private_data;
>  
>  		rw_ctx = ceph_find_rw_context(fi);
> -		if (rw_ctx)
> +		if (rw_ctx) {
> +			kfree(priv);
>  			return 0;

This is not working. When reaching here by read() system call, we always
have non-null rw_ctx.  (As I read the code and also verified with gdb)
ceph_add_rw_context() is invoked in ceph_read_iter().

> +		}
> +		priv->file_ra_pages = file->f_ra.ra_pages;
> +		priv->file_ra_disabled = !!(file->f_mode & FMODE_RANDOM);

'!!' is not needed. From coding-style.rst: "When using bool types the
!! construction is not needed, which eliminates a class of bugs".

Thanks
Hu Weiwen

>  	}
>  
>  	/*
> @@ -425,27 +434,39 @@ static int ceph_init_request(struct netfs_io_request *rreq, struct file *file)
>  	ret = ceph_try_get_caps(inode, CEPH_CAP_FILE_RD, want, true, &got);
>  	if (ret < 0) {
>  		dout("start_read %p, error getting cap\n", inode);
> -		return ret;
> +		goto out;
>  	}
>  
>  	if (!(got & want)) {
>  		dout("start_read %p, no cache cap\n", inode);
> -		return -EACCES;
> +		ret = -EACCES;
> +		goto out;
> +	}
> +	if (ret == 0) {
> +		ret = -EACCES;
> +		goto out;
>  	}
> -	if (ret == 0)
> -		return -EACCES;
>  
> -	rreq->netfs_priv = (void *)(uintptr_t)got;
> -	return 0;
> +	priv->caps = got;
> +	rreq->netfs_priv = priv;
> +
> +out:
> +	if (ret)
> +		kfree(priv);
> +
> +	return ret;
>  }
>  
>  static void ceph_netfs_free_request(struct netfs_io_request *rreq)
>  {
> -	struct ceph_inode_info *ci = ceph_inode(rreq->inode);
> -	int got = (uintptr_t)rreq->netfs_priv;
> +	struct ceph_netfs_request_data *priv = rreq->netfs_priv;
> +
> +	if (!priv)
> +		return;
>  
> -	if (got)
> -		ceph_put_cap_refs(ci, got);
> +	ceph_put_cap_refs(ceph_inode(rreq->inode), priv->caps);
> +	kfree(priv);
> +	rreq->netfs_priv = NULL;
>  }
>  
>  const struct netfs_request_ops ceph_netfs_ops = {
> diff --git a/fs/ceph/super.h b/fs/ceph/super.h
> index a226d36b3ecb..1233f53f6e0b 100644
> --- a/fs/ceph/super.h
> +++ b/fs/ceph/super.h
> @@ -470,6 +470,19 @@ struct ceph_inode_info {
>  #endif
>  };
>  
> +struct ceph_netfs_request_data {
> +	int caps;
> +
> +	/*
> +	 * Maximum size of a file readahead request.
> +	 * The posix_fadvise could update the bdi's default ra_pages.
> +	 */
> +	unsigned int file_ra_pages;
> +
> +	/* Set it if posix_fadvise disables file readahead entirely */
> +	bool file_ra_disabled;
> +};
> +
>  static inline struct ceph_inode_info *
>  ceph_inode(const struct inode *inode)
>  {
> -- 
> 2.40.0
>
Xiubo Li May 12, 2023, 2:41 p.m. UTC | #2
On 5/12/23 22:13, 胡玮文 wrote:
> On Thu, May 11, 2023 at 11:03:34AM +0800, xiubli@redhat.com wrote:
>> From: Xiubo Li <xiubli@redhat.com>
>>
>> We need to save the 'f_ra.ra_pages' to expand the readahead window
>> later.
>>
>> Cc: stable@vger.kernel.org
>> Fixes: 49870056005c ("ceph: convert ceph_readpages to ceph_readahead")
>> URL: https://lore.kernel.org/ceph-devel/20230504082510.247-1-sehuww@mail.scut.edu.cn
>> URL: https://www.spinics.net/lists/ceph-users/msg76183.html
>> Cc: Hu Weiwen <sehuww@mail.scut.edu.cn>
>> Signed-off-by: Xiubo Li <xiubli@redhat.com>
>> ---
>>   fs/ceph/addr.c  | 43 ++++++++++++++++++++++++++++++++-----------
>>   fs/ceph/super.h | 13 +++++++++++++
>>   2 files changed, 45 insertions(+), 11 deletions(-)
>>
>> diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
>> index 3b20873733af..db55fce13324 100644
>> --- a/fs/ceph/addr.c
>> +++ b/fs/ceph/addr.c
>> @@ -404,18 +404,27 @@ static int ceph_init_request(struct netfs_io_request *rreq, struct file *file)
>>   {
>>   	struct inode *inode = rreq->inode;
>>   	int got = 0, want = CEPH_CAP_FILE_CACHE;
>> +	struct ceph_netfs_request_data *priv;
>>   	int ret = 0;
>>   
>>   	if (rreq->origin != NETFS_READAHEAD)
>>   		return 0;
>>   
>> +	priv = kzalloc(sizeof(*priv), GFP_NOFS);
>> +	if (!priv)
>> +		return -ENOMEM;
>> +
>>   	if (file) {
>>   		struct ceph_rw_context *rw_ctx;
>>   		struct ceph_file_info *fi = file->private_data;
>>   
>>   		rw_ctx = ceph_find_rw_context(fi);
>> -		if (rw_ctx)
>> +		if (rw_ctx) {
>> +			kfree(priv);
>>   			return 0;
> This is not working. When reaching here by read() system call, we always
> have non-null rw_ctx.  (As I read the code and also verified with gdb)
> ceph_add_rw_context() is invoked in ceph_read_iter().

This should work:

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index e1bf90059112..d3e37e01c3d0 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -444,13 +444,14 @@ static int ceph_init_request(struct 
netfs_io_request *rreq, struct file *file)
                 struct ceph_rw_context *rw_ctx;
                 struct ceph_file_info *fi = file->private_data;

+               priv->file_ra_pages = file->f_ra.ra_pages;
+               priv->file_ra_disabled = file->f_mode & FMODE_RANDOM;
+
                 rw_ctx = ceph_find_rw_context(fi);
                 if (rw_ctx) {
-                       kfree(priv);
+                       rreq->netfs_priv = priv;
                         return 0;
                 }
-               priv->file_ra_pages = file->f_ra.ra_pages;
-               priv->file_ra_disabled = !!(file->f_mode & FMODE_RANDOM);
         }

         /*

Thanks

- Xiubo

>> +		}
>> +		priv->file_ra_pages = file->f_ra.ra_pages;
>> +		priv->file_ra_disabled = !!(file->f_mode & FMODE_RANDOM);
> '!!' is not needed. From coding-style.rst: "When using bool types the
> !! construction is not needed, which eliminates a class of bugs".
>
> Thanks
> Hu Weiwen
>
>>   	}
>>   
>>   	/*
>> @@ -425,27 +434,39 @@ static int ceph_init_request(struct netfs_io_request *rreq, struct file *file)
>>   	ret = ceph_try_get_caps(inode, CEPH_CAP_FILE_RD, want, true, &got);
>>   	if (ret < 0) {
>>   		dout("start_read %p, error getting cap\n", inode);
>> -		return ret;
>> +		goto out;
>>   	}
>>   
>>   	if (!(got & want)) {
>>   		dout("start_read %p, no cache cap\n", inode);
>> -		return -EACCES;
>> +		ret = -EACCES;
>> +		goto out;
>> +	}
>> +	if (ret == 0) {
>> +		ret = -EACCES;
>> +		goto out;
>>   	}
>> -	if (ret == 0)
>> -		return -EACCES;
>>   
>> -	rreq->netfs_priv = (void *)(uintptr_t)got;
>> -	return 0;
>> +	priv->caps = got;
>> +	rreq->netfs_priv = priv;
>> +
>> +out:
>> +	if (ret)
>> +		kfree(priv);
>> +
>> +	return ret;
>>   }
>>   
>>   static void ceph_netfs_free_request(struct netfs_io_request *rreq)
>>   {
>> -	struct ceph_inode_info *ci = ceph_inode(rreq->inode);
>> -	int got = (uintptr_t)rreq->netfs_priv;
>> +	struct ceph_netfs_request_data *priv = rreq->netfs_priv;
>> +
>> +	if (!priv)
>> +		return;
>>   
>> -	if (got)
>> -		ceph_put_cap_refs(ci, got);
>> +	ceph_put_cap_refs(ceph_inode(rreq->inode), priv->caps);
>> +	kfree(priv);
>> +	rreq->netfs_priv = NULL;
>>   }
>>   
>>   const struct netfs_request_ops ceph_netfs_ops = {
>> diff --git a/fs/ceph/super.h b/fs/ceph/super.h
>> index a226d36b3ecb..1233f53f6e0b 100644
>> --- a/fs/ceph/super.h
>> +++ b/fs/ceph/super.h
>> @@ -470,6 +470,19 @@ struct ceph_inode_info {
>>   #endif
>>   };
>>   
>> +struct ceph_netfs_request_data {
>> +	int caps;
>> +
>> +	/*
>> +	 * Maximum size of a file readahead request.
>> +	 * The posix_fadvise could update the bdi's default ra_pages.
>> +	 */
>> +	unsigned int file_ra_pages;
>> +
>> +	/* Set it if posix_fadvise disables file readahead entirely */
>> +	bool file_ra_disabled;
>> +};
>> +
>>   static inline struct ceph_inode_info *
>>   ceph_inode(const struct inode *inode)
>>   {
>> -- 
>> 2.40.0
>>
diff mbox series

Patch

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 3b20873733af..db55fce13324 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -404,18 +404,27 @@  static int ceph_init_request(struct netfs_io_request *rreq, struct file *file)
 {
 	struct inode *inode = rreq->inode;
 	int got = 0, want = CEPH_CAP_FILE_CACHE;
+	struct ceph_netfs_request_data *priv;
 	int ret = 0;
 
 	if (rreq->origin != NETFS_READAHEAD)
 		return 0;
 
+	priv = kzalloc(sizeof(*priv), GFP_NOFS);
+	if (!priv)
+		return -ENOMEM;
+
 	if (file) {
 		struct ceph_rw_context *rw_ctx;
 		struct ceph_file_info *fi = file->private_data;
 
 		rw_ctx = ceph_find_rw_context(fi);
-		if (rw_ctx)
+		if (rw_ctx) {
+			kfree(priv);
 			return 0;
+		}
+		priv->file_ra_pages = file->f_ra.ra_pages;
+		priv->file_ra_disabled = !!(file->f_mode & FMODE_RANDOM);
 	}
 
 	/*
@@ -425,27 +434,39 @@  static int ceph_init_request(struct netfs_io_request *rreq, struct file *file)
 	ret = ceph_try_get_caps(inode, CEPH_CAP_FILE_RD, want, true, &got);
 	if (ret < 0) {
 		dout("start_read %p, error getting cap\n", inode);
-		return ret;
+		goto out;
 	}
 
 	if (!(got & want)) {
 		dout("start_read %p, no cache cap\n", inode);
-		return -EACCES;
+		ret = -EACCES;
+		goto out;
+	}
+	if (ret == 0) {
+		ret = -EACCES;
+		goto out;
 	}
-	if (ret == 0)
-		return -EACCES;
 
-	rreq->netfs_priv = (void *)(uintptr_t)got;
-	return 0;
+	priv->caps = got;
+	rreq->netfs_priv = priv;
+
+out:
+	if (ret)
+		kfree(priv);
+
+	return ret;
 }
 
 static void ceph_netfs_free_request(struct netfs_io_request *rreq)
 {
-	struct ceph_inode_info *ci = ceph_inode(rreq->inode);
-	int got = (uintptr_t)rreq->netfs_priv;
+	struct ceph_netfs_request_data *priv = rreq->netfs_priv;
+
+	if (!priv)
+		return;
 
-	if (got)
-		ceph_put_cap_refs(ci, got);
+	ceph_put_cap_refs(ceph_inode(rreq->inode), priv->caps);
+	kfree(priv);
+	rreq->netfs_priv = NULL;
 }
 
 const struct netfs_request_ops ceph_netfs_ops = {
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index a226d36b3ecb..1233f53f6e0b 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -470,6 +470,19 @@  struct ceph_inode_info {
 #endif
 };
 
+struct ceph_netfs_request_data {
+	int caps;
+
+	/*
+	 * Maximum size of a file readahead request.
+	 * The posix_fadvise could update the bdi's default ra_pages.
+	 */
+	unsigned int file_ra_pages;
+
+	/* Set it if posix_fadvise disables file readahead entirely */
+	bool file_ra_disabled;
+};
+
 static inline struct ceph_inode_info *
 ceph_inode(const struct inode *inode)
 {