freebsd-skq/sys/net/vnet.h
Marko Zec 0a705ab66f Instead of spamming the console on each curvnet recursion event, print
out each such call graph only once, along with a stack backtrace.  This
should make kernels built with VNET_DEBUG reasonably usable again in
busy / production environments.

Introduce a new DDB command "show vnetrcrs" which dumps the whole log
of distinctive curvnet recursion events.  This might be useful when
recursion reports get burried / lost too deep in the message buffer.
In the later case stack backtraces are not available.

Reviewed by:	bz
MFC after:	3 days
2010-02-04 07:55:42 +00:00

391 lines
12 KiB
C

/*-
* Copyright (c) 2006-2009 University of Zagreb
* Copyright (c) 2006-2009 FreeBSD Foundation
* All rights reserved.
*
* This software was developed by the University of Zagreb and the
* FreeBSD Foundation under sponsorship by the Stichting NLnet and the
* FreeBSD Foundation.
*
* Copyright (c) 2009 Jeffrey Roberson <jeff@freebsd.org>
* Copyright (c) 2009 Robert N. M. Watson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*-
* This header file defines several sets of interfaces supporting virtualized
* network stacks:
*
* - Definition of 'struct vnet' and functions and macros to allocate/free/
* manipulate it.
*
* - A virtual network stack memory allocator, which provides support for
* virtualized global variables via a special linker set, set_vnet.
*
* - Virtualized sysinits/sysuninits, which allow constructors and
* destructors to be run for each network stack subsystem as virtual
* instances are created and destroyed.
*
* If VIMAGE isn't compiled into the kernel, virtualized global variables
* compile to normal global variables, and virtualized sysinits to regular
* sysinits.
*/
#ifndef _NET_VNET_H_
#define _NET_VNET_H_
/*
* struct vnet describes a virtualized network stack, and is primarily a
* pointer to storage for virtualized global variables. Expose to userspace
* as required for libkvm.
*/
#if defined(_KERNEL) || defined(_WANT_VNET)
#include <sys/queue.h>
struct vnet {
LIST_ENTRY(vnet) vnet_le; /* all vnets list */
u_int vnet_magic_n;
u_int vnet_ifcnt;
u_int vnet_sockcnt;
void *vnet_data_mem;
uintptr_t vnet_data_base;
};
#define VNET_MAGIC_N 0x3e0d8f29
/*
* These two virtual network stack allocator definitions are also required
* for libkvm so that it can evaluate virtualized global variables.
*/
#define VNET_SETNAME "set_vnet"
#define VNET_SYMPREFIX "vnet_entry_"
#endif
#ifdef _KERNEL
#ifdef VIMAGE
#include <sys/lock.h>
#include <sys/proc.h> /* for struct thread */
#include <sys/rwlock.h>
#include <sys/sx.h>
/*
* Functions to allocate and destroy virtual network stacks.
*/
struct vnet *vnet_alloc(void);
void vnet_destroy(struct vnet *vnet);
/*
* The current virtual network stack -- we may wish to move this to struct
* pcpu in the future.
*/
#define curvnet curthread->td_vnet
/*
* Various macros -- get and set the current network stack, but also
* assertions.
*/
#ifdef VNET_DEBUG
void vnet_log_recursion(struct vnet *, const char *, int);
#define VNET_ASSERT(condition) \
if (!(condition)) { \
printf("VNET_ASSERT @ %s:%d %s():\n", \
__FILE__, __LINE__, __FUNCTION__); \
panic(#condition); \
}
#define CURVNET_SET_QUIET(arg) \
VNET_ASSERT((arg)->vnet_magic_n == VNET_MAGIC_N); \
struct vnet *saved_vnet = curvnet; \
const char *saved_vnet_lpush = curthread->td_vnet_lpush; \
curvnet = arg; \
curthread->td_vnet_lpush = __FUNCTION__;
#define CURVNET_SET_VERBOSE(arg) \
CURVNET_SET_QUIET(arg) \
if (saved_vnet) \
vnet_log_recursion(saved_vnet, saved_vnet_lpush, __LINE__);
#define CURVNET_SET(arg) CURVNET_SET_VERBOSE(arg)
#define CURVNET_RESTORE() \
VNET_ASSERT(saved_vnet == NULL || \
saved_vnet->vnet_magic_n == VNET_MAGIC_N); \
curvnet = saved_vnet; \
curthread->td_vnet_lpush = saved_vnet_lpush;
#else /* !VNET_DEBUG */
#define VNET_ASSERT(condition)
#define CURVNET_SET(arg) \
struct vnet *saved_vnet = curvnet; \
curvnet = arg;
#define CURVNET_SET_VERBOSE(arg) CURVNET_SET(arg)
#define CURVNET_SET_QUIET(arg) CURVNET_SET(arg)
#define CURVNET_RESTORE() \
curvnet = saved_vnet;
#endif /* VNET_DEBUG */
extern struct vnet *vnet0;
#define IS_DEFAULT_VNET(arg) ((arg) == vnet0)
#define CRED_TO_VNET(cr) (cr)->cr_prison->pr_vnet
#define TD_TO_VNET(td) CRED_TO_VNET((td)->td_ucred)
#define P_TO_VNET(p) CRED_TO_VNET((p)->p_ucred)
/*
* Global linked list of all virtual network stacks, along with read locks to
* access it. If a caller may sleep while accessing the list, it must use
* the sleepable lock macros.
*/
LIST_HEAD(vnet_list_head, vnet);
extern struct vnet_list_head vnet_head;
extern struct rwlock vnet_rwlock;
extern struct sx vnet_sxlock;
#define VNET_LIST_RLOCK() sx_slock(&vnet_sxlock)
#define VNET_LIST_RLOCK_NOSLEEP() rw_rlock(&vnet_rwlock)
#define VNET_LIST_RUNLOCK() sx_sunlock(&vnet_sxlock)
#define VNET_LIST_RUNLOCK_NOSLEEP() rw_runlock(&vnet_rwlock)
/*
* Iteration macros to walk the global list of virtual network stacks.
*/
#define VNET_ITERATOR_DECL(arg) struct vnet *arg
#define VNET_FOREACH(arg) LIST_FOREACH((arg), &vnet_head, vnet_le)
/*
* Virtual network stack memory allocator, which allows global variables to
* be automatically instantiated for each network stack instance.
*/
__asm__(
#if defined(__arm__)
".section " VNET_SETNAME ", \"aw\", %progbits\n"
#else
".section " VNET_SETNAME ", \"aw\", @progbits\n"
#endif
"\t.p2align " __XSTRING(CACHE_LINE_SHIFT) "\n"
"\t.previous");
#define VNET_NAME(n) vnet_entry_##n
#define VNET_DECLARE(t, n) extern t VNET_NAME(n)
#define VNET_DEFINE(t, n) t VNET_NAME(n) __section(VNET_SETNAME) __used
#define _VNET_PTR(b, n) (__typeof(VNET_NAME(n))*) \
((b) + (uintptr_t)&VNET_NAME(n))
#define _VNET(b, n) (*_VNET_PTR(b, n))
/*
* Virtualized global variable accessor macros.
*/
#define VNET_VNET_PTR(vnet, n) _VNET_PTR((vnet)->vnet_data_base, n)
#define VNET_VNET(vnet, n) (*VNET_VNET_PTR((vnet), n))
#define VNET_PTR(n) VNET_VNET_PTR(curvnet, n)
#define VNET(n) VNET_VNET(curvnet, n)
/*
* Virtual network stack allocator interfaces from the kernel linker.
*/
void *vnet_data_alloc(int size);
void vnet_data_copy(void *start, int size);
void vnet_data_free(void *start_arg, int size);
/*
* Sysctl variants for vnet-virtualized global variables. Include
* <sys/sysctl.h> to expose these definitions.
*
* Note: SYSCTL_PROC() handler functions will need to resolve pointer
* arguments themselves, if required.
*/
#ifdef SYSCTL_OID
int vnet_sysctl_handle_int(SYSCTL_HANDLER_ARGS);
int vnet_sysctl_handle_opaque(SYSCTL_HANDLER_ARGS);
int vnet_sysctl_handle_string(SYSCTL_HANDLER_ARGS);
int vnet_sysctl_handle_uint(SYSCTL_HANDLER_ARGS);
#define SYSCTL_VNET_INT(parent, nbr, name, access, ptr, val, descr) \
SYSCTL_OID(parent, nbr, name, \
CTLTYPE_INT|CTLFLAG_MPSAFE|CTLFLAG_VNET|(access), \
ptr, val, vnet_sysctl_handle_int, "I", descr)
#define SYSCTL_VNET_PROC(parent, nbr, name, access, ptr, arg, handler, \
fmt, descr) \
SYSCTL_OID(parent, nbr, name, CTLFLAG_VNET|(access), ptr, arg, \
handler, fmt, descr)
#define SYSCTL_VNET_STRING(parent, nbr, name, access, arg, len, descr) \
SYSCTL_OID(parent, nbr, name, \
CTLTYPE_STRING|CTLFLAG_VNET|(access), \
arg, len, vnet_sysctl_handle_string, "A", descr)
#define SYSCTL_VNET_STRUCT(parent, nbr, name, access, ptr, type, descr) \
SYSCTL_OID(parent, nbr, name, \
CTLTYPE_OPAQUE|CTLFLAG_VNET|(access), ptr, \
sizeof(struct type), vnet_sysctl_handle_opaque, "S," #type, \
descr)
#define SYSCTL_VNET_UINT(parent, nbr, name, access, ptr, val, descr) \
SYSCTL_OID(parent, nbr, name, \
CTLTYPE_UINT|CTLFLAG_MPSAFE|CTLFLAG_VNET|(access), \
ptr, val, vnet_sysctl_handle_uint, "IU", descr)
#define VNET_SYSCTL_ARG(req, arg1) do { \
if (arg1 != NULL) \
arg1 = (void *)(TD_TO_VNET((req)->td)->vnet_data_base + \
(uintptr_t)(arg1)); \
} while (0)
#endif /* SYSCTL_OID */
/*
* Virtual sysinit mechanism, allowing network stack components to declare
* startup and shutdown methods to be run when virtual network stack
* instances are created and destroyed.
*/
#include <sys/kernel.h>
/*
* SYSINIT/SYSUNINIT variants that provide per-vnet constructors and
* destructors.
*/
struct vnet_sysinit {
enum sysinit_sub_id subsystem;
enum sysinit_elem_order order;
sysinit_cfunc_t func;
const void *arg;
TAILQ_ENTRY(vnet_sysinit) link;
};
#define VNET_SYSINIT(ident, subsystem, order, func, arg) \
static struct vnet_sysinit ident ## _vnet_init = { \
subsystem, \
order, \
(sysinit_cfunc_t)(sysinit_nfunc_t)func, \
(arg) \
}; \
SYSINIT(vnet_init_ ## ident, subsystem, order, \
vnet_register_sysinit, &ident ## _vnet_init); \
SYSUNINIT(vnet_init_ ## ident, subsystem, order, \
vnet_deregister_sysinit, &ident ## _vnet_init)
#define VNET_SYSUNINIT(ident, subsystem, order, func, arg) \
static struct vnet_sysinit ident ## _vnet_uninit = { \
subsystem, \
order, \
(sysinit_cfunc_t)(sysinit_nfunc_t)func, \
(arg) \
}; \
SYSINIT(vnet_uninit_ ## ident, subsystem, order, \
vnet_register_sysuninit, &ident ## _vnet_uninit); \
SYSUNINIT(vnet_uninit_ ## ident, subsystem, order, \
vnet_deregister_sysuninit, &ident ## _vnet_uninit)
/*
* Run per-vnet sysinits or sysuninits during vnet creation/destruction.
*/
void vnet_sysinit(void);
void vnet_sysuninit(void);
/*
* Interfaces for managing per-vnet constructors and destructors.
*/
void vnet_register_sysinit(void *arg);
void vnet_register_sysuninit(void *arg);
void vnet_deregister_sysinit(void *arg);
void vnet_deregister_sysuninit(void *arg);
#else /* !VIMAGE */
/*
* Various virtual network stack macros compile to no-ops without VIMAGE.
*/
#define curvnet NULL
#define VNET_ASSERT(condition)
#define CURVNET_SET(arg)
#define CURVNET_SET_QUIET(arg)
#define CURVNET_RESTORE()
#define VNET_LIST_RLOCK()
#define VNET_LIST_RLOCK_NOSLEEP()
#define VNET_LIST_RUNLOCK()
#define VNET_LIST_RUNLOCK_NOSLEEP()
#define VNET_ITERATOR_DECL(arg)
#define VNET_FOREACH(arg)
#define IS_DEFAULT_VNET(arg) 1
#define CRED_TO_VNET(cr) NULL
#define TD_TO_VNET(td) NULL
#define P_TO_VNET(p) NULL
/*
* Versions of the VNET macros that compile to normal global variables and
* standard sysctl definitions.
*/
#define VNET_NAME(n) n
#define VNET_DECLARE(t, n) extern t n
#define VNET_DEFINE(t, n) t n
#define _VNET_PTR(b, n) &VNET_NAME(n)
/*
* Virtualized global variable accessor macros.
*/
#define VNET_VNET_PTR(vnet, n) (&(n))
#define VNET_VNET(vnet, n) (n)
#define VNET_PTR(n) (&(n))
#define VNET(n) (n)
/*
* When VIMAGE isn't compiled into the kernel, virtaulized SYSCTLs simply
* become normal SYSCTLs.
*/
#ifdef SYSCTL_OID
#define SYSCTL_VNET_INT(parent, nbr, name, access, ptr, val, descr) \
SYSCTL_INT(parent, nbr, name, access, ptr, val, descr)
#define SYSCTL_VNET_PROC(parent, nbr, name, access, ptr, arg, handler, \
fmt, descr) \
SYSCTL_PROC(parent, nbr, name, access, ptr, arg, handler, fmt, \
descr)
#define SYSCTL_VNET_STRING(parent, nbr, name, access, arg, len, descr) \
SYSCTL_STRING(parent, nbr, name, access, arg, len, descr)
#define SYSCTL_VNET_STRUCT(parent, nbr, name, access, ptr, type, descr) \
SYSCTL_STRUCT(parent, nbr, name, access, ptr, type, descr)
#define SYSCTL_VNET_UINT(parent, nbr, name, access, ptr, val, descr) \
SYSCTL_UINT(parent, nbr, name, access, ptr, val, descr)
#define VNET_SYSCTL_ARG(req, arg1)
#endif /* SYSCTL_OID */
/*
* When VIMAGE isn't compiled into the kernel, VNET_SYSINIT/VNET_SYSUNINIT
* map into normal sysinits, which have the same ordering properties.
*/
#define VNET_SYSINIT(ident, subsystem, order, func, arg) \
SYSINIT(ident, subsystem, order, func, arg)
#define VNET_SYSUNINIT(ident, subsystem, order, func, arg) \
SYSUNINIT(ident, subsystem, order, func, arg)
#endif /* VIMAGE */
#endif /* _KERNEL */
#endif /* !_NET_VNET_H_ */