linux/fs/xfs/xfs_stats.c
Dave Chinner 11ef38afe9 xfs: make xfs btree stats less huge
Embedding a switch statement in every btree stats inc/add adds a lot
of code overhead to the core btree infrastructure paths. Stats are
supposed to be small and lightweight, but the btree stats have
become big and bloated as we've added more btrees. It needs fixing
because the reflink code will just add more overhead again.

Convert the v2 btree stats to arrays instead of independent
variables, and instead use the type to index the specific btree
array via an enum. This allows us to use array based indexing
to update the stats, rather than having to derefence variables
specific to the btree type.

If we then wrap the xfsstats structure in a union and place uint32_t
array beside it, and calculate the correct btree stats array base
array index when creating a btree cursor,  we can easily access
entries in the stats structure without having to switch names based
on the btree type.

We then replace with the switch statement with a simple set of stats
wrapper macros, resulting in a significant simplification of the
btree stats code, and:

   text	   data	    bss	    dec	    hex	filename
  48905	    144	      8	  49057	   bfa1	fs/xfs/libxfs/xfs_btree.o.old
  36793	    144	      8	  36945	   9051	fs/xfs/libxfs/xfs_btree.o

it reduces the core btree infrastructure code size by close to 25%!

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-12-05 14:38:58 +11:00

197 lines
5.2 KiB
C

/*
* Copyright (c) 2000-2003,2005 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
*/
#include "xfs.h"
#include <linux/proc_fs.h>
struct xstats xfsstats;
static int counter_val(struct xfsstats __percpu *stats, int idx)
{
int val = 0, cpu;
for_each_possible_cpu(cpu)
val += *(((__u32 *)per_cpu_ptr(stats, cpu) + idx));
return val;
}
int xfs_stats_format(struct xfsstats __percpu *stats, char *buf)
{
int i, j;
int len = 0;
__uint64_t xs_xstrat_bytes = 0;
__uint64_t xs_write_bytes = 0;
__uint64_t xs_read_bytes = 0;
static const struct xstats_entry {
char *desc;
int endpoint;
} xstats[] = {
{ "extent_alloc", XFSSTAT_END_EXTENT_ALLOC },
{ "abt", XFSSTAT_END_ALLOC_BTREE },
{ "blk_map", XFSSTAT_END_BLOCK_MAPPING },
{ "bmbt", XFSSTAT_END_BLOCK_MAP_BTREE },
{ "dir", XFSSTAT_END_DIRECTORY_OPS },
{ "trans", XFSSTAT_END_TRANSACTIONS },
{ "ig", XFSSTAT_END_INODE_OPS },
{ "log", XFSSTAT_END_LOG_OPS },
{ "push_ail", XFSSTAT_END_TAIL_PUSHING },
{ "xstrat", XFSSTAT_END_WRITE_CONVERT },
{ "rw", XFSSTAT_END_READ_WRITE_OPS },
{ "attr", XFSSTAT_END_ATTRIBUTE_OPS },
{ "icluster", XFSSTAT_END_INODE_CLUSTER },
{ "vnodes", XFSSTAT_END_VNODE_OPS },
{ "buf", XFSSTAT_END_BUF },
{ "abtb2", XFSSTAT_END_ABTB_V2 },
{ "abtc2", XFSSTAT_END_ABTC_V2 },
{ "bmbt2", XFSSTAT_END_BMBT_V2 },
{ "ibt2", XFSSTAT_END_IBT_V2 },
{ "fibt2", XFSSTAT_END_FIBT_V2 },
{ "rmapbt", XFSSTAT_END_RMAP_V2 },
{ "refcntbt", XFSSTAT_END_REFCOUNT },
/* we print both series of quota information together */
{ "qm", XFSSTAT_END_QM },
};
/* Loop over all stats groups */
for (i = j = 0; i < ARRAY_SIZE(xstats); i++) {
len += snprintf(buf + len, PATH_MAX - len, "%s",
xstats[i].desc);
/* inner loop does each group */
for (; j < xstats[i].endpoint; j++)
len += snprintf(buf + len, PATH_MAX - len, " %u",
counter_val(stats, j));
len += snprintf(buf + len, PATH_MAX - len, "\n");
}
/* extra precision counters */
for_each_possible_cpu(i) {
xs_xstrat_bytes += per_cpu_ptr(stats, i)->s.xs_xstrat_bytes;
xs_write_bytes += per_cpu_ptr(stats, i)->s.xs_write_bytes;
xs_read_bytes += per_cpu_ptr(stats, i)->s.xs_read_bytes;
}
len += snprintf(buf + len, PATH_MAX-len, "xpc %Lu %Lu %Lu\n",
xs_xstrat_bytes, xs_write_bytes, xs_read_bytes);
len += snprintf(buf + len, PATH_MAX-len, "debug %u\n",
#if defined(DEBUG)
1);
#else
0);
#endif
return len;
}
void xfs_stats_clearall(struct xfsstats __percpu *stats)
{
int c;
__uint32_t vn_active;
xfs_notice(NULL, "Clearing xfsstats");
for_each_possible_cpu(c) {
preempt_disable();
/* save vn_active, it's a universal truth! */
vn_active = per_cpu_ptr(stats, c)->s.vn_active;
memset(per_cpu_ptr(stats, c), 0, sizeof(*stats));
per_cpu_ptr(stats, c)->s.vn_active = vn_active;
preempt_enable();
}
}
/* legacy quota interfaces */
#ifdef CONFIG_XFS_QUOTA
static int xqm_proc_show(struct seq_file *m, void *v)
{
/* maximum; incore; ratio free to inuse; freelist */
seq_printf(m, "%d\t%d\t%d\t%u\n",
0, counter_val(xfsstats.xs_stats, XFSSTAT_END_XQMSTAT),
0, counter_val(xfsstats.xs_stats, XFSSTAT_END_XQMSTAT + 1));
return 0;
}
static int xqm_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, xqm_proc_show, NULL);
}
static const struct file_operations xqm_proc_fops = {
.open = xqm_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
/* legacy quota stats interface no 2 */
static int xqmstat_proc_show(struct seq_file *m, void *v)
{
int j;
seq_printf(m, "qm");
for (j = XFSSTAT_END_IBT_V2; j < XFSSTAT_END_XQMSTAT; j++)
seq_printf(m, " %u", counter_val(xfsstats.xs_stats, j));
seq_putc(m, '\n');
return 0;
}
static int xqmstat_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, xqmstat_proc_show, NULL);
}
static const struct file_operations xqmstat_proc_fops = {
.owner = THIS_MODULE,
.open = xqmstat_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#endif /* CONFIG_XFS_QUOTA */
#ifdef CONFIG_PROC_FS
int
xfs_init_procfs(void)
{
if (!proc_mkdir("fs/xfs", NULL))
return -ENOMEM;
if (!proc_symlink("fs/xfs/stat", NULL,
"/sys/fs/xfs/stats/stats"))
goto out;
#ifdef CONFIG_XFS_QUOTA
if (!proc_create("fs/xfs/xqmstat", 0, NULL,
&xqmstat_proc_fops))
goto out;
if (!proc_create("fs/xfs/xqm", 0, NULL,
&xqm_proc_fops))
goto out;
#endif
return 0;
out:
remove_proc_subtree("fs/xfs", NULL);
return -ENOMEM;
}
void
xfs_cleanup_procfs(void)
{
remove_proc_subtree("fs/xfs", NULL);
}
#endif /* CONFIG_PROC_FS */