alistair23-linux/fs/xfs/xfs_linux.h
Christoph Hellwig 0030807c66 xfs: revert to using a kthread for AIL pushing
Currently we have a few issues with the way the workqueue code is used to
implement AIL pushing:

 - it accidentally uses the same workqueue as the syncer action, and thus
   can be prevented from running if there are enough sync actions active
   in the system.
 - it doesn't use the HIGHPRI flag to queue at the head of the queue of
   work items

At this point I'm not confident enough in getting all the workqueue flags and
tweaks right to provide a perfectly reliable execution context for AIL
pushing, which is the most important piece in XFS to make forward progress
when the log fills.

Revert back to use a kthread per filesystem which fixes all the above issues
at the cost of having a task struct and stack around for each mounted
filesystem.  In addition this also gives us much better ways to diagnose
any issues involving hung AIL pushing and removes a small amount of code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Stefan Priebe <s.priebe@profihost.ag>
Tested-by: Stefan Priebe <s.priebe@profihost.ag>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 11:02:49 -05:00

312 lines
7.5 KiB
C

/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef __XFS_LINUX__
#define __XFS_LINUX__
#include <linux/types.h>
/*
* XFS_BIG_BLKNOS needs block layer disk addresses to be 64 bits.
* XFS_BIG_INUMS requires XFS_BIG_BLKNOS to be set.
*/
#if defined(CONFIG_LBDAF) || (BITS_PER_LONG == 64)
# define XFS_BIG_BLKNOS 1
# define XFS_BIG_INUMS 1
#else
# define XFS_BIG_BLKNOS 0
# define XFS_BIG_INUMS 0
#endif
#include "xfs_types.h"
#include "kmem.h"
#include "mrlock.h"
#include "time.h"
#include "uuid.h"
#include <linux/semaphore.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/file.h>
#include <linux/swap.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/bitops.h>
#include <linux/major.h>
#include <linux/pagemap.h>
#include <linux/vfs.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/proc_fs.h>
#include <linux/sort.h>
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <linux/delay.h>
#include <linux/log2.h>
#include <linux/spinlock.h>
#include <linux/random.h>
#include <linux/ctype.h>
#include <linux/writeback.h>
#include <linux/capability.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/list_sort.h>
#include <asm/page.h>
#include <asm/div64.h>
#include <asm/param.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
#include <asm/unaligned.h>
#include "xfs_vnode.h"
#include "xfs_stats.h"
#include "xfs_sysctl.h"
#include "xfs_iops.h"
#include "xfs_aops.h"
#include "xfs_super.h"
#include "xfs_buf.h"
#include "xfs_message.h"
#ifdef __BIG_ENDIAN
#define XFS_NATIVE_HOST 1
#else
#undef XFS_NATIVE_HOST
#endif
/*
* Feature macros (disable/enable)
*/
#ifdef CONFIG_SMP
#define HAVE_PERCPU_SB /* per cpu superblock counters are a 2.6 feature */
#else
#undef HAVE_PERCPU_SB /* per cpu superblock counters are a 2.6 feature */
#endif
#define irix_sgid_inherit xfs_params.sgid_inherit.val
#define irix_symlink_mode xfs_params.symlink_mode.val
#define xfs_panic_mask xfs_params.panic_mask.val
#define xfs_error_level xfs_params.error_level.val
#define xfs_syncd_centisecs xfs_params.syncd_timer.val
#define xfs_stats_clear xfs_params.stats_clear.val
#define xfs_inherit_sync xfs_params.inherit_sync.val
#define xfs_inherit_nodump xfs_params.inherit_nodump.val
#define xfs_inherit_noatime xfs_params.inherit_noatim.val
#define xfs_buf_timer_centisecs xfs_params.xfs_buf_timer.val
#define xfs_buf_age_centisecs xfs_params.xfs_buf_age.val
#define xfs_inherit_nosymlinks xfs_params.inherit_nosym.val
#define xfs_rotorstep xfs_params.rotorstep.val
#define xfs_inherit_nodefrag xfs_params.inherit_nodfrg.val
#define xfs_fstrm_centisecs xfs_params.fstrm_timer.val
#define current_cpu() (raw_smp_processor_id())
#define current_pid() (current->pid)
#define current_test_flags(f) (current->flags & (f))
#define current_set_flags_nested(sp, f) \
(*(sp) = current->flags, current->flags |= (f))
#define current_clear_flags_nested(sp, f) \
(*(sp) = current->flags, current->flags &= ~(f))
#define current_restore_flags_nested(sp, f) \
(current->flags = ((current->flags & ~(f)) | (*(sp) & (f))))
#define spinlock_destroy(lock)
#define NBBY 8 /* number of bits per byte */
/*
* Size of block device i/o is parameterized here.
* Currently the system supports page-sized i/o.
*/
#define BLKDEV_IOSHIFT PAGE_CACHE_SHIFT
#define BLKDEV_IOSIZE (1<<BLKDEV_IOSHIFT)
/* number of BB's per block device block */
#define BLKDEV_BB BTOBB(BLKDEV_IOSIZE)
#define ENOATTR ENODATA /* Attribute not found */
#define EWRONGFS EINVAL /* Mount with wrong filesystem type */
#define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
#define SYNCHRONIZE() barrier()
#define __return_address __builtin_return_address(0)
#define XFS_PROJID_DEFAULT 0
#define MAXPATHLEN 1024
#define MIN(a,b) (min(a,b))
#define MAX(a,b) (max(a,b))
#define howmany(x, y) (((x)+((y)-1))/(y))
/*
* Various platform dependent calls that don't fit anywhere else
*/
#define xfs_sort(a,n,s,fn) sort(a,n,s,fn,NULL)
#define xfs_stack_trace() dump_stack()
/* Move the kernel do_div definition off to one side */
#if defined __i386__
/* For ia32 we need to pull some tricks to get past various versions
* of the compiler which do not like us using do_div in the middle
* of large functions.
*/
static inline __u32 xfs_do_div(void *a, __u32 b, int n)
{
__u32 mod;
switch (n) {
case 4:
mod = *(__u32 *)a % b;
*(__u32 *)a = *(__u32 *)a / b;
return mod;
case 8:
{
unsigned long __upper, __low, __high, __mod;
__u64 c = *(__u64 *)a;
__upper = __high = c >> 32;
__low = c;
if (__high) {
__upper = __high % (b);
__high = __high / (b);
}
asm("divl %2":"=a" (__low), "=d" (__mod):"rm" (b), "0" (__low), "1" (__upper));
asm("":"=A" (c):"a" (__low),"d" (__high));
*(__u64 *)a = c;
return __mod;
}
}
/* NOTREACHED */
return 0;
}
/* Side effect free 64 bit mod operation */
static inline __u32 xfs_do_mod(void *a, __u32 b, int n)
{
switch (n) {
case 4:
return *(__u32 *)a % b;
case 8:
{
unsigned long __upper, __low, __high, __mod;
__u64 c = *(__u64 *)a;
__upper = __high = c >> 32;
__low = c;
if (__high) {
__upper = __high % (b);
__high = __high / (b);
}
asm("divl %2":"=a" (__low), "=d" (__mod):"rm" (b), "0" (__low), "1" (__upper));
asm("":"=A" (c):"a" (__low),"d" (__high));
return __mod;
}
}
/* NOTREACHED */
return 0;
}
#else
static inline __u32 xfs_do_div(void *a, __u32 b, int n)
{
__u32 mod;
switch (n) {
case 4:
mod = *(__u32 *)a % b;
*(__u32 *)a = *(__u32 *)a / b;
return mod;
case 8:
mod = do_div(*(__u64 *)a, b);
return mod;
}
/* NOTREACHED */
return 0;
}
/* Side effect free 64 bit mod operation */
static inline __u32 xfs_do_mod(void *a, __u32 b, int n)
{
switch (n) {
case 4:
return *(__u32 *)a % b;
case 8:
{
__u64 c = *(__u64 *)a;
return do_div(c, b);
}
}
/* NOTREACHED */
return 0;
}
#endif
#undef do_div
#define do_div(a, b) xfs_do_div(&(a), (b), sizeof(a))
#define do_mod(a, b) xfs_do_mod(&(a), (b), sizeof(a))
static inline __uint64_t roundup_64(__uint64_t x, __uint32_t y)
{
x += y - 1;
do_div(x, y);
return(x * y);
}
static inline __uint64_t howmany_64(__uint64_t x, __uint32_t y)
{
x += y - 1;
do_div(x, y);
return x;
}
/* ARM old ABI has some weird alignment/padding */
#if defined(__arm__) && !defined(__ARM_EABI__)
#define __arch_pack __attribute__((packed))
#else
#define __arch_pack
#endif
#define ASSERT_ALWAYS(expr) \
(unlikely(expr) ? (void)0 : assfail(#expr, __FILE__, __LINE__))
#ifndef DEBUG
#define ASSERT(expr) ((void)0)
#ifndef STATIC
# define STATIC static noinline
#endif
#else /* DEBUG */
#define ASSERT(expr) \
(unlikely(expr) ? (void)0 : assfail(#expr, __FILE__, __LINE__))
#ifndef STATIC
# define STATIC noinline
#endif
#endif /* DEBUG */
#endif /* __XFS_LINUX__ */