Commit a4ae3081 authored by Chuck Lever's avatar Chuck Lever
Browse files

SUNRPC: Move client-side disconnect injection 



Disconnect injection stress-tests the ability for both client and
server implementations to behave resiliently in the face of network
instability.

Convert the existing client-side disconnect injection infrastructure
to use the kernel's generic error injection facility. The generic
facility has a richer set of injection criteria.

Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent c782af25

include/linux/sunrpc/xprt.h

+0 −18
Original line number Diff line number Diff line
@@ -288,7 +288,6 @@ struct rpc_xprt { 
	const char		*address_strings[RPC_DISPLAY_MAX];

#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)

	struct dentry		*debugfs;		/* debugfs directory */

	atomic_t		inject_disconnect;

#endif

	struct rcu_head		rcu;

	const struct xprt_class	*xprt_class;
@@ -502,21 +501,4 @@ static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) 
	return test_and_set_bit(XPRT_BINDING, &xprt->state);

}



#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)

extern unsigned int rpc_inject_disconnect;

static inline void xprt_inject_disconnect(struct rpc_xprt *xprt)

{

	if (!rpc_inject_disconnect)

		return;

	if (atomic_dec_return(&xprt->inject_disconnect))

		return;

	atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect);

	xprt->ops->inject_disconnect(xprt);

}

#else

static inline void xprt_inject_disconnect(struct rpc_xprt *xprt)

{

}

#endif



#endif /* _LINUX_SUNRPC_XPRT_H */

net/sunrpc/debugfs.c

+14 −64
Original line number Diff line number Diff line
@@ -16,8 +16,6 @@ static struct dentry *topdir; 
static struct dentry *rpc_clnt_dir;

static struct dentry *rpc_xprt_dir;



unsigned int rpc_inject_disconnect;



static int

tasks_show(struct seq_file *f, void *v)

{
@@ -237,8 +235,6 @@ rpc_xprt_debugfs_register(struct rpc_xprt *xprt) 
	/* make tasks file */

	debugfs_create_file("info", S_IFREG | 0400, xprt->debugfs, xprt,

			    &xprt_info_fops);



	atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect);

}



void
@@ -248,62 +244,26 @@ rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt) 
	xprt->debugfs = NULL;

}



static int

fault_open(struct inode *inode, struct file *filp)

{

	filp->private_data = kmalloc(128, GFP_KERNEL);

	if (!filp->private_data)

		return -ENOMEM;

	return 0;

}

#if IS_ENABLED(CONFIG_FAIL_SUNRPC)

struct fail_sunrpc_attr fail_sunrpc = {

	.attr			= FAULT_ATTR_INITIALIZER,

};

EXPORT_SYMBOL_GPL(fail_sunrpc);



static int

fault_release(struct inode *inode, struct file *filp)

static void fail_sunrpc_init(void)

{

	kfree(filp->private_data);

	return 0;

}

	struct dentry *dir;



static ssize_t

fault_disconnect_read(struct file *filp, char __user *user_buf,

		      size_t len, loff_t *offset)

{

	char *buffer = (char *)filp->private_data;

	size_t size;

	dir = fault_create_debugfs_attr("fail_sunrpc", NULL,

					&fail_sunrpc.attr);



	size = sprintf(buffer, "%u\n", rpc_inject_disconnect);

	return simple_read_from_buffer(user_buf, len, offset, buffer, size);

	debugfs_create_bool("ignore-client-disconnect", S_IFREG | 0600, dir,

			    &fail_sunrpc.ignore_client_disconnect);

}



static ssize_t

fault_disconnect_write(struct file *filp, const char __user *user_buf,

		       size_t len, loff_t *offset)

#else

static void fail_sunrpc_init(void)

{

	char buffer[16];



	if (len >= sizeof(buffer))

		len = sizeof(buffer) - 1;

	if (copy_from_user(buffer, user_buf, len))

		return -EFAULT;

	buffer[len] = '\0';

	if (kstrtouint(buffer, 10, &rpc_inject_disconnect))

		return -EINVAL;

	return len;

}



static const struct file_operations fault_disconnect_fops = {

	.owner		= THIS_MODULE,

	.open		= fault_open,

	.read		= fault_disconnect_read,

	.write		= fault_disconnect_write,

	.release	= fault_release,

};



#if IS_ENABLED(CONFIG_FAIL_SUNRPC)

struct fail_sunrpc_attr fail_sunrpc = {

	.attr			= FAULT_ATTR_INITIALIZER,

};

EXPORT_SYMBOL_GPL(fail_sunrpc);

#endif



void __exit
@@ -318,21 +278,11 @@ sunrpc_debugfs_exit(void) 
void __init

sunrpc_debugfs_init(void)

{

	struct dentry *rpc_fault_dir;



	topdir = debugfs_create_dir("sunrpc", NULL);



	rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);



	rpc_xprt_dir = debugfs_create_dir("rpc_xprt", topdir);



	rpc_fault_dir = debugfs_create_dir("inject_fault", topdir);



	debugfs_create_file("disconnect", S_IFREG | 0400, rpc_fault_dir, NULL,

			    &fault_disconnect_fops);



#if IS_ENABLED(CONFIG_FAIL_SUNRPC)

	fault_create_debugfs_attr("fail_sunrpc", NULL,

				  &fail_sunrpc.attr);

#endif

	fail_sunrpc_init();

}

net/sunrpc/fail.h

+2 −0
Original line number Diff line number Diff line
@@ -12,6 +12,8 @@ 


struct fail_sunrpc_attr {

	struct fault_attr	attr;



	bool			ignore_client_disconnect;

};



extern struct fail_sunrpc_attr fail_sunrpc;

net/sunrpc/xprt.c

+14 −0
Original line number Diff line number Diff line
@@ -56,6 +56,7 @@ 


#include "sunrpc.h"

#include "sysfs.h"

#include "fail.h"



/*

 * Local variables
@@ -855,6 +856,19 @@ xprt_init_autodisconnect(struct timer_list *t) 
	queue_work(xprtiod_workqueue, &xprt->task_cleanup);

}



#if IS_ENABLED(CONFIG_FAIL_SUNRPC)

static void xprt_inject_disconnect(struct rpc_xprt *xprt)

{

	if (!fail_sunrpc.ignore_client_disconnect &&

	    should_fail(&fail_sunrpc.attr, 1))

		xprt->ops->inject_disconnect(xprt);

}

#else

static inline void xprt_inject_disconnect(struct rpc_xprt *xprt)

{

}

#endif



bool xprt_lock_connect(struct rpc_xprt *xprt,

		struct rpc_task *task,

		void *cookie)