On 30/10/2023 12:57, Ariel Miculas wrote:
On 23/10/29 08:33PM, Phillip Lougher wrote:
On 29/10/2023 16:19, Ariel Miculas wrote:
When SQUASHFS_CHOICE_DECOMP_BY_MOUNT is set, the "threads" mount option
can be used to specify the decompression mode: single-threaded,
multi-threaded, percpu or the number of threads used for decompression.
When SQUASHFS_CHOICE_DECOMP_BY_MOUNT is not set and
SQUASHFS_DECOMP_MULTI is set, the "threads" option can also be used to
specify the number of threads used for decompression. This mount option
is only mentioned in fs/squashfs/Kconfig, which makes it difficult to
find.
Another mount option available is "errors", which can be configured to
panic the kernel when squashfs errors are encountered.
Add both these options to the squashfs documentation, making them more
noticeable.
Signed-off-by: Ariel Miculas <amiculas@xxxxxxxxx>
Looks good to me.
Reviewed-by: Phillip Lougher <phillip@xxxxxxxxxxxxxxx>
Unfortunately, it seems this is not quite correct either:
There is the config option 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.
```
that depends on SQUASHFS_DECOMP_MULTI.
So I think I should take my v1 patch and specify that the "threads="
mount option depends on SQUASHFS_MOUNT_DECOMP_THREADS. There's no need
to specify SQUASHFS_DECOMP_MULTI, because SQUASHFS_MOUNT_DECOMP_THREADS
already depends on it.
Sorry, you have to specify SQUASHFS_DECOMP_MULTI to be able to specify
SQUASHFS_MOUNT_DECOMP_THREADS if SQUASHFS_DECOMP_BY_MOUNT is unselected.
Just try it, do make menuconfig, ensure SQUASHFS_CHOICE_DECOMP_BY_MOUNT
is unselected, select Single threaded decompression and you won't be
able to specify SQUASHFS_MOUNT_DECOMP_THREADS.
That was the point of my review. What bit don't you understand?
Phillip
What do you think?
Regards,
Ariel
