squashfs: allows users to configure the number of decompression threads

The maximum number of threads in the decompressor_multi.c file is fixed
and cannot be adjusted according to user needs.  Therefore, the mount
parameter needs to be added to allow users to configure the number of
threads as required.  The upper limit is num_online_cpus() * 2.

Link: https://lkml.kernel.org/r/20221019030930.130456-3-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Jianguo Chen <chenjianguo3@huawei.com>
Cc: Jubin Zhong <zhongjubin@huawei.com>
Cc: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Xiaoming Ni 2022-10-19 11:09:30 +08:00 committed by Andrew Morton
parent 80f784098f
commit fb40fe04f9
4 changed files with 66 additions and 10 deletions

View file

@ -73,11 +73,10 @@ config SQUASHFS_CHOICE_DECOMP_BY_MOUNT
select SQUASHFS_DECOMP_SINGLE
select SQUASHFS_DECOMP_MULTI
select SQUASHFS_DECOMP_MULTI_PERCPU
select SQUASHFS_MOUNT_DECOMP_THREADS
help
Compile all parallel decompression modes and specify the
decompression mode by setting "threads=" during mount.
threads=<single|multi|percpu>
default Decompressor parallelisation is SQUASHFS_DECOMP_SINGLE
choice
@ -127,6 +126,19 @@ config SQUASHFS_COMPILE_DECOMP_MULTI_PERCPU
decompression is load-balanced across the cores.
endchoice
config SQUASHFS_MOUNT_DECOMP_THREADS
bool "Add the mount parameter 'threads=' for squashfs"
depends on SQUASHFS
depends on SQUASHFS_DECOMP_MULTI
default n
help
Use threads= to set the decompression parallel mode and the number of threads.
If SQUASHFS_CHOICE_DECOMP_BY_MOUNT=y
threads=<single|multi|percpu|1|2|3|...>
else
threads=<2|3|...>
The upper limit is num_online_cpus() * 2.
config SQUASHFS_XATTR
bool "Squashfs XATTR support"
depends on SQUASHFS

View file

@ -144,7 +144,7 @@ static struct decomp_stream *get_decomp_stream(struct squashfs_sb_info *msblk,
* If there is no available decomp and already full,
* let's wait for releasing decomp from other users.
*/
if (stream->avail_decomp >= MAX_DECOMPRESSOR)
if (stream->avail_decomp >= msblk->max_thread_num)
goto wait;
/* Let's allocate new decomp */
@ -160,7 +160,7 @@ static struct decomp_stream *get_decomp_stream(struct squashfs_sb_info *msblk,
}
stream->avail_decomp++;
WARN_ON(stream->avail_decomp > MAX_DECOMPRESSOR);
WARN_ON(stream->avail_decomp > msblk->max_thread_num);
mutex_unlock(&stream->mutex);
break;

View file

@ -67,5 +67,6 @@ struct squashfs_sb_info {
unsigned int ids;
bool panic_on_errors;
const struct squashfs_decompressor_thread_ops *thread_ops;
int max_thread_num;
};
#endif

View file

@ -53,6 +53,7 @@ enum squashfs_param {
struct squashfs_mount_opts {
enum Opt_errors errors;
const struct squashfs_decompressor_thread_ops *thread_ops;
int thread_num;
};
static const struct constant_table squashfs_param_errors[] = {
@ -67,7 +68,8 @@ static const struct fs_parameter_spec squashfs_fs_parameters[] = {
{}
};
static int squashfs_parse_param_threads(const char *str, struct squashfs_mount_opts *opts)
static int squashfs_parse_param_threads_str(const char *str, struct squashfs_mount_opts *opts)
{
#ifdef CONFIG_SQUASHFS_CHOICE_DECOMP_BY_MOUNT
if (strcmp(str, "single") == 0) {
@ -86,6 +88,42 @@ static int squashfs_parse_param_threads(const char *str, struct squashfs_mount_o
return -EINVAL;
}
static int squashfs_parse_param_threads_num(const char *str, struct squashfs_mount_opts *opts)
{
#ifdef CONFIG_SQUASHFS_MOUNT_DECOMP_THREADS
int ret;
unsigned long num;
ret = kstrtoul(str, 0, &num);
if (ret != 0)
return -EINVAL;
if (num > 1) {
opts->thread_ops = &squashfs_decompressor_multi;
if (num > opts->thread_ops->max_decompressors())
return -EINVAL;
opts->thread_num = (int)num;
return 0;
}
#ifdef CONFIG_SQUASHFS_DECOMP_SINGLE
if (num == 1) {
opts->thread_ops = &squashfs_decompressor_single;
opts->thread_num = 1;
return 0;
}
#endif
#endif /* !CONFIG_SQUASHFS_MOUNT_DECOMP_THREADS */
return -EINVAL;
}
static int squashfs_parse_param_threads(const char *str, struct squashfs_mount_opts *opts)
{
int ret = squashfs_parse_param_threads_str(str, opts);
if (ret == 0)
return ret;
return squashfs_parse_param_threads_num(str, opts);
}
static int squashfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
{
struct squashfs_mount_opts *opts = fc->fs_private;
@ -194,6 +232,11 @@ static int squashfs_fill_super(struct super_block *sb, struct fs_context *fc)
goto failed_mount;
}
msblk->thread_ops = opts->thread_ops;
if (opts->thread_num == 0) {
msblk->max_thread_num = msblk->thread_ops->max_decompressors();
} else {
msblk->max_thread_num = opts->thread_num;
}
/* Check the MAJOR & MINOR versions and lookup compression type */
msblk->decompressor = supported_squashfs_filesystem(
@ -279,7 +322,7 @@ static int squashfs_fill_super(struct super_block *sb, struct fs_context *fc)
/* Allocate read_page block */
msblk->read_page = squashfs_cache_init("data",
msblk->thread_ops->max_decompressors(), msblk->block_size);
msblk->max_thread_num, msblk->block_size);
if (msblk->read_page == NULL) {
errorf(fc, "Failed to allocate read_page block");
goto failed_mount;
@ -467,14 +510,13 @@ static int squashfs_show_options(struct seq_file *s, struct dentry *root)
seq_puts(s, ",threads=single");
return 0;
}
if (msblk->thread_ops == &squashfs_decompressor_multi) {
seq_puts(s, ",threads=multi");
return 0;
}
if (msblk->thread_ops == &squashfs_decompressor_percpu) {
seq_puts(s, ",threads=percpu");
return 0;
}
#endif
#ifdef CONFIG_SQUASHFS_MOUNT_DECOMP_THREADS
seq_printf(s, ",threads=%d", msblk->max_thread_num);
#endif
return 0;
}
@ -496,6 +538,7 @@ static int squashfs_init_fs_context(struct fs_context *fc)
#else
#error "fail: unknown squashfs decompression thread mode?"
#endif
opts->thread_num = 0;
fc->fs_private = opts;
fc->ops = &squashfs_context_ops;
return 0;