From a4ae308143961bf688e1c8a62f6604e62b491120 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 5 Aug 2021 10:25:49 -0400 Subject: 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: Chuck Lever --- include/linux/sunrpc/xprt.h | 18 ----------- net/sunrpc/debugfs.c | 78 ++++++++------------------------------------- net/sunrpc/fail.h | 2 ++ net/sunrpc/xprt.c | 14 ++++++++ 4 files changed, 30 insertions(+), 82 deletions(-) diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index c8c39f22d3b1..b15c1f07162d 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -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 */ diff --git a/net/sunrpc/debugfs.c b/net/sunrpc/debugfs.c index eaeb51f83abd..04e453ad3508 100644 --- a/net/sunrpc/debugfs.c +++ b/net/sunrpc/debugfs.c @@ -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(); } diff --git a/net/sunrpc/fail.h b/net/sunrpc/fail.h index 1d402b0d3453..62c1b9fd59e2 100644 --- a/net/sunrpc/fail.h +++ b/net/sunrpc/fail.h @@ -12,6 +12,8 @@ struct fail_sunrpc_attr { struct fault_attr attr; + + bool ignore_client_disconnect; }; extern struct fail_sunrpc_attr fail_sunrpc; diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index fb6db09725c7..05abe344a269 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -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) -- cgit