linux/fs/gfs2/trans.c
Benjamin Marzinski 5e687eac1b GFS2: Various gfs2_logd improvements
This patch contains various tweaks to how log flushes and active item writeback
work. gfs2_logd is now managed by a waitqueue, and gfs2_log_reseve now waits
for gfs2_logd to do the log flushing.  Multiple functions were rewritten to
remove the need to call gfs2_log_lock(). Instead of using one test to see if
gfs2_logd had work to do, there are now seperate tests to check if there
are two many buffers in the incore log or if there are two many items on the
active items list.

This patch is a port of a patch Steve Whitehouse wrote about a year ago, with
some minor changes.  Since gfs2_ail1_start always submits all the active items,
it no longer needs to keep track of the first ai submitted, so this has been
removed. In gfs2_log_reserve(), the order of the calls to
prepare_to_wait_exclusive() and wake_up() when firing off the logd thread has
been switched.  If it called wake_up first there was a small window for a race,
where logd could run and return before gfs2_log_reserve was ready to get woken
up. If gfs2_logd ran, but did not free up enough blocks, gfs2_log_reserve()
would be left waiting for gfs2_logd to eventualy run because it timed out.
Finally, gt_logd_secs, which controls how long to wait before gfs2_logd times
out, and flushes the log, can now be set on mount with ar_commit.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2010-05-05 09:39:18 +01:00

193 lines
4.6 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/kallsyms.h>
#include <linux/gfs2_ondisk.h>
#include "gfs2.h"
#include "incore.h"
#include "glock.h"
#include "log.h"
#include "lops.h"
#include "meta_io.h"
#include "trans.h"
#include "util.h"
#include "trace_gfs2.h"
int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
unsigned int revokes)
{
struct gfs2_trans *tr;
int error;
BUG_ON(current->journal_info);
BUG_ON(blocks == 0 && revokes == 0);
if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
return -EROFS;
tr = kzalloc(sizeof(struct gfs2_trans), GFP_NOFS);
if (!tr)
return -ENOMEM;
tr->tr_ip = (unsigned long)__builtin_return_address(0);
tr->tr_blocks = blocks;
tr->tr_revokes = revokes;
tr->tr_reserved = 1;
if (blocks)
tr->tr_reserved += 6 + blocks;
if (revokes)
tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
sizeof(u64));
INIT_LIST_HEAD(&tr->tr_list_buf);
gfs2_holder_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &tr->tr_t_gh);
error = gfs2_glock_nq(&tr->tr_t_gh);
if (error)
goto fail_holder_uninit;
error = gfs2_log_reserve(sdp, tr->tr_reserved);
if (error)
goto fail_gunlock;
current->journal_info = tr;
return 0;
fail_gunlock:
gfs2_glock_dq(&tr->tr_t_gh);
fail_holder_uninit:
gfs2_holder_uninit(&tr->tr_t_gh);
kfree(tr);
return error;
}
/**
* gfs2_log_release - Release a given number of log blocks
* @sdp: The GFS2 superblock
* @blks: The number of blocks
*
*/
static void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
{
atomic_add(blks, &sdp->sd_log_blks_free);
trace_gfs2_log_blocks(sdp, blks);
gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
sdp->sd_jdesc->jd_blocks);
up_read(&sdp->sd_log_flush_lock);
}
void gfs2_trans_end(struct gfs2_sbd *sdp)
{
struct gfs2_trans *tr = current->journal_info;
BUG_ON(!tr);
current->journal_info = NULL;
if (!tr->tr_touched) {
gfs2_log_release(sdp, tr->tr_reserved);
if (tr->tr_t_gh.gh_gl) {
gfs2_glock_dq(&tr->tr_t_gh);
gfs2_holder_uninit(&tr->tr_t_gh);
kfree(tr);
}
return;
}
if (gfs2_assert_withdraw(sdp, tr->tr_num_buf <= tr->tr_blocks)) {
fs_err(sdp, "tr_num_buf = %u, tr_blocks = %u ",
tr->tr_num_buf, tr->tr_blocks);
print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
}
if (gfs2_assert_withdraw(sdp, tr->tr_num_revoke <= tr->tr_revokes)) {
fs_err(sdp, "tr_num_revoke = %u, tr_revokes = %u ",
tr->tr_num_revoke, tr->tr_revokes);
print_symbol(KERN_WARNING "GFS2: Transaction created at: %s\n", tr->tr_ip);
}
gfs2_log_commit(sdp, tr);
if (tr->tr_t_gh.gh_gl) {
gfs2_glock_dq(&tr->tr_t_gh);
gfs2_holder_uninit(&tr->tr_t_gh);
kfree(tr);
}
if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)
gfs2_log_flush(sdp, NULL);
}
/**
* gfs2_trans_add_bh - Add a to-be-modified buffer to the current transaction
* @gl: the glock the buffer belongs to
* @bh: The buffer to add
* @meta: True in the case of adding metadata
*
*/
void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
struct gfs2_bufdata *bd;
bd = bh->b_private;
if (bd)
gfs2_assert(sdp, bd->bd_gl == gl);
else {
gfs2_attach_bufdata(gl, bh, meta);
bd = bh->b_private;
}
lops_add(sdp, &bd->bd_le);
}
void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
{
BUG_ON(!list_empty(&bd->bd_le.le_list));
BUG_ON(!list_empty(&bd->bd_ail_st_list));
BUG_ON(!list_empty(&bd->bd_ail_gl_list));
lops_init_le(&bd->bd_le, &gfs2_revoke_lops);
lops_add(sdp, &bd->bd_le);
}
void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len)
{
struct gfs2_bufdata *bd, *tmp;
struct gfs2_trans *tr = current->journal_info;
unsigned int n = len;
gfs2_log_lock(sdp);
list_for_each_entry_safe(bd, tmp, &sdp->sd_log_le_revoke, bd_le.le_list) {
if ((bd->bd_blkno >= blkno) && (bd->bd_blkno < (blkno + len))) {
list_del_init(&bd->bd_le.le_list);
gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);
sdp->sd_log_num_revoke--;
kmem_cache_free(gfs2_bufdata_cachep, bd);
tr->tr_num_revoke_rm++;
if (--n == 0)
break;
}
}
gfs2_log_unlock(sdp);
}
void gfs2_trans_add_rg(struct gfs2_rgrpd *rgd)
{
lops_add(rgd->rd_sbd, &rgd->rd_le);
}