[lustre-devel] [PATCH 05/18] lustre: llite: fast read implementation

[NeilBrown]

On Mon, Jul 02 2018, James Simmons wrote:

> +static ssize_t fast_read_store(struct kobject *kobj,
> +			       struct attribute *attr,
> +			       const char *buffer,
> +			       size_t count)
> +{
> +	struct ll_sb_info *sbi = container_of(kobj, struct ll_sb_info,
> +					      ll_kobj);
> +	bool val;
> +	int rc;
> +
> +	rc = kstrtobool(buffer, &val);
> +	if (rc)
> +		return rc;
> +
> +	spin_lock(&sbi->ll_lock);
> +	if (val)
> +		sbi->ll_flags |= LL_SBI_FAST_READ;
> +	else
> +		sbi->ll_flags &= ~LL_SBI_FAST_READ;
> +	spin_unlock(&sbi->ll_lock);

This is a little odd... no other code uses ll_lock to protect updates to
ll_flags.  Various other places (e.g. checksum_pages_store()) updates it
unprotected.

Maybe there all need to use ll_lock for protection.


Thanks,
NeilBrown
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