> Am 12.12.2019 um 15:12 schrieb Pandurov, Milan <milanpa@xxxxxxxxx>:
>
> We can store reference to kvm_stats_debugfs_item instead of copying
> its values to kvm_stat_data.
> This allows us to remove duplicated code and usage of temporary
> kvm_stat_data inside vm_stat_get et al.
>
> Signed-off-by: Milan Pandurov <milanpa@xxxxxxxxx>
>
> ---
> v1 -> v2:
> - fix compile issues
> - add reference to kvm_stats_debugfs_item in kvm_stat_data
> - return -EINVAL when writing !0
> - use explicit switch case instead of ops indirection
> - fix checkpatch warning: Change S_IWUGO to 0222
>
> v2 -> v3:
> - remove unused kvm_stat_ops
> - fix style issues
>
> v3 -> v4:
> - revert: Change S_IWUGO to 0222
I don't see v3 in my inbox and v4 includes the S_IEUGO change that Christian mentioned should not be in.
Apart from this change, the patch looks fine to me. So if you change the mask to 0222 again, feel free to add my
Reviewed-by: Alexander Graf <graf@xxxxxxxxxx>
Alex
> ---
> include/linux/kvm_host.h | 7 +-
> virt/kvm/kvm_main.c | 142 +++++++++++++++++++--------------------
> 2 files changed, 76 insertions(+), 73 deletions(-)
>
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 7ed1e2f8641e..d3f2c0eae857 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1109,9 +1109,8 @@ enum kvm_stat_kind {
> };
>
> struct kvm_stat_data {
> - int offset;
> - int mode;
> struct kvm *kvm;
> + struct kvm_stats_debugfs_item *dbgfs_item;
> };
>
> struct kvm_stats_debugfs_item {
> @@ -1120,6 +1119,10 @@ struct kvm_stats_debugfs_item {
> enum kvm_stat_kind kind;
> int mode;
> };
> +
> +#define KVM_DBGFS_GET_MODE(dbgfs_item) \
> + ((dbgfs_item)->mode ? (dbgfs_item)->mode : 0644)
> +
> extern struct kvm_stats_debugfs_item debugfs_entries[];
> extern struct dentry *kvm_debugfs_dir;
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 00268290dcbd..286bca3804b1 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -113,7 +113,7 @@ struct dentry *kvm_debugfs_dir;
> EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
>
> static int kvm_debugfs_num_entries;
> -static const struct file_operations *stat_fops_per_vm[];
> +static const struct file_operations stat_fops_per_vm;
>
> static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
> unsigned long arg);
> @@ -650,11 +650,11 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
> return -ENOMEM;
>
> stat_data->kvm = kvm;
> - stat_data->offset = p->offset;
> - stat_data->mode = p->mode ? p->mode : 0644;
> + stat_data->dbgfs_item = p;
> kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
> - debugfs_create_file(p->name, stat_data->mode, kvm->debugfs_dentry,
> - stat_data, stat_fops_per_vm[p->kind]);
> + debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
> + kvm->debugfs_dentry, stat_data,
> + &stat_fops_per_vm);
> }
> return 0;
> }
> @@ -4013,8 +4013,9 @@ static int kvm_debugfs_open(struct inode *inode, struct file *file,
> return -ENOENT;
>
> if (simple_attr_open(inode, file, get,
> - stat_data->mode & S_IWUGO ? set : NULL,
> - fmt)) {
> + KVM_DBGFS_GET_MODE(stat_data->dbgfs_item) & S_IWUGO
> + ? set : NULL,
> + fmt)) {
> kvm_put_kvm(stat_data->kvm);
> return -ENOMEM;
> }
> @@ -4033,105 +4034,111 @@ static int kvm_debugfs_release(struct inode *inode, struct file *file)
> return 0;
> }
>
> -static int vm_stat_get_per_vm(void *data, u64 *val)
> +static int kvm_get_stat_per_vm(struct kvm *kvm, size_t offset, u64 *val)
> {
> - struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> + *val = *(ulong *)((void *)kvm + offset);
>
> - *val = *(ulong *)((void *)stat_data->kvm + stat_data->offset);
> + return 0;
> +}
> +
> +static int kvm_clear_stat_per_vm(struct kvm *kvm, size_t offset)
> +{
> + *(ulong *)((void *)kvm + offset) = 0;
>
> return 0;
> }
>
> -static int vm_stat_clear_per_vm(void *data, u64 val)
> +static int kvm_get_stat_per_vcpu(struct kvm *kvm, size_t offset, u64 *val)
> {
> - struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> + int i;
> + struct kvm_vcpu *vcpu;
>
> - if (val)
> - return -EINVAL;
> + *val = 0;
>
> - *(ulong *)((void *)stat_data->kvm + stat_data->offset) = 0;
> + kvm_for_each_vcpu(i, vcpu, kvm)
> + *val += *(u64 *)((void *)vcpu + offset);
>
> return 0;
> }
>
> -static int vm_stat_get_per_vm_open(struct inode *inode, struct file *file)
> +static int kvm_clear_stat_per_vcpu(struct kvm *kvm, size_t offset)
> {
> - __simple_attr_check_format("%llu\n", 0ull);
> - return kvm_debugfs_open(inode, file, vm_stat_get_per_vm,
> - vm_stat_clear_per_vm, "%llu\n");
> -}
> + int i;
> + struct kvm_vcpu *vcpu;
>
> -static const struct file_operations vm_stat_get_per_vm_fops = {
> - .owner = THIS_MODULE,
> - .open = vm_stat_get_per_vm_open,
> - .release = kvm_debugfs_release,
> - .read = simple_attr_read,
> - .write = simple_attr_write,
> - .llseek = no_llseek,
> -};
> + kvm_for_each_vcpu(i, vcpu, kvm)
> + *(u64 *)((void *)vcpu + offset) = 0;
> +
> + return 0;
> +}
>
> -static int vcpu_stat_get_per_vm(void *data, u64 *val)
> +static int kvm_stat_data_get(void *data, u64 *val)
> {
> - int i;
> + int r = -EFAULT;
> struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> - struct kvm_vcpu *vcpu;
> -
> - *val = 0;
>
> - kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
> - *val += *(u64 *)((void *)vcpu + stat_data->offset);
> + switch (stat_data->dbgfs_item->kind) {
> + case KVM_STAT_VM:
> + r = kvm_get_stat_per_vm(stat_data->kvm,
> + stat_data->dbgfs_item->offset, val);
> + break;
> + case KVM_STAT_VCPU:
> + r = kvm_get_stat_per_vcpu(stat_data->kvm,
> + stat_data->dbgfs_item->offset, val);
> + break;
> + }
>
> - return 0;
> + return r;
> }
>
> -static int vcpu_stat_clear_per_vm(void *data, u64 val)
> +static int kvm_stat_data_clear(void *data, u64 val)
> {
> - int i;
> + int r = -EFAULT;
> struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
> - struct kvm_vcpu *vcpu;
>
> if (val)
> return -EINVAL;
>
> - kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
> - *(u64 *)((void *)vcpu + stat_data->offset) = 0;
> + switch (stat_data->dbgfs_item->kind) {
> + case KVM_STAT_VM:
> + r = kvm_clear_stat_per_vm(stat_data->kvm,
> + stat_data->dbgfs_item->offset);
> + break;
> + case KVM_STAT_VCPU:
> + r = kvm_clear_stat_per_vcpu(stat_data->kvm,
> + stat_data->dbgfs_item->offset);
> + break;
> + }
>
> - return 0;
> + return r;
> }
>
> -static int vcpu_stat_get_per_vm_open(struct inode *inode, struct file *file)
> +static int kvm_stat_data_open(struct inode *inode, struct file *file)
> {
> __simple_attr_check_format("%llu\n", 0ull);
> - return kvm_debugfs_open(inode, file, vcpu_stat_get_per_vm,
> - vcpu_stat_clear_per_vm, "%llu\n");
> + return kvm_debugfs_open(inode, file, kvm_stat_data_get,
> + kvm_stat_data_clear, "%llu\n");
> }
>
> -static const struct file_operations vcpu_stat_get_per_vm_fops = {
> - .owner = THIS_MODULE,
> - .open = vcpu_stat_get_per_vm_open,
> +static const struct file_operations stat_fops_per_vm = {
> + .owner = THIS_MODULE,
> + .open = kvm_stat_data_open,
> .release = kvm_debugfs_release,
> - .read = simple_attr_read,
> - .write = simple_attr_write,
> - .llseek = no_llseek,
> -};
> -
> -static const struct file_operations *stat_fops_per_vm[] = {
> - [KVM_STAT_VCPU] = &vcpu_stat_get_per_vm_fops,
> - [KVM_STAT_VM] = &vm_stat_get_per_vm_fops,
> + .read = simple_attr_read,
> + .write = simple_attr_write,
> + .llseek = no_llseek,
> };
>
> static int vm_stat_get(void *_offset, u64 *val)
> {
> unsigned offset = (long)_offset;
> struct kvm *kvm;
> - struct kvm_stat_data stat_tmp = {.offset = offset};
> u64 tmp_val;
>
> *val = 0;
> mutex_lock(&kvm_lock);
> list_for_each_entry(kvm, &vm_list, vm_list) {
> - stat_tmp.kvm = kvm;
> - vm_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
> + kvm_get_stat_per_vm(kvm, offset, &tmp_val);
> *val += tmp_val;
> }
> mutex_unlock(&kvm_lock);
> @@ -4142,15 +4149,13 @@ static int vm_stat_clear(void *_offset, u64 val)
> {
> unsigned offset = (long)_offset;
> struct kvm *kvm;
> - struct kvm_stat_data stat_tmp = {.offset = offset};
>
> if (val)
> return -EINVAL;
>
> mutex_lock(&kvm_lock);
> list_for_each_entry(kvm, &vm_list, vm_list) {
> - stat_tmp.kvm = kvm;
> - vm_stat_clear_per_vm((void *)&stat_tmp, 0);
> + kvm_clear_stat_per_vm(kvm, offset);
> }
> mutex_unlock(&kvm_lock);
>
> @@ -4163,14 +4168,12 @@ static int vcpu_stat_get(void *_offset, u64 *val)
> {
> unsigned offset = (long)_offset;
> struct kvm *kvm;
> - struct kvm_stat_data stat_tmp = {.offset = offset};
> u64 tmp_val;
>
> *val = 0;
> mutex_lock(&kvm_lock);
> list_for_each_entry(kvm, &vm_list, vm_list) {
> - stat_tmp.kvm = kvm;
> - vcpu_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
> + kvm_get_stat_per_vcpu(kvm, offset, &tmp_val);
> *val += tmp_val;
> }
> mutex_unlock(&kvm_lock);
> @@ -4181,15 +4184,13 @@ static int vcpu_stat_clear(void *_offset, u64 val)
> {
> unsigned offset = (long)_offset;
> struct kvm *kvm;
> - struct kvm_stat_data stat_tmp = {.offset = offset};
>
> if (val)
> return -EINVAL;
>
> mutex_lock(&kvm_lock);
> list_for_each_entry(kvm, &vm_list, vm_list) {
> - stat_tmp.kvm = kvm;
> - vcpu_stat_clear_per_vm((void *)&stat_tmp, 0);
> + kvm_clear_stat_per_vcpu(kvm, offset);
> }
> mutex_unlock(&kvm_lock);
>
> @@ -4262,9 +4263,8 @@ static void kvm_init_debug(void)
>
> kvm_debugfs_num_entries = 0;
> for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
> - int mode = p->mode ? p->mode : 0644;
> - debugfs_create_file(p->name, mode, kvm_debugfs_dir,
> - (void *)(long)p->offset,
> + debugfs_create_file(p->name, KVM_DBGFS_GET_MODE(p),
> + kvm_debugfs_dir, (void *)(long)p->offset,
> stat_fops[p->kind]);
> }
> }
> --
> 2.17.1
>
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