Re: [PATCH 3/8] Uprobe: Rename map_info to uprobe_map_info

From: Steven Rostedt
Date: Thu Mar 15 2018 - 12:44:59 EST


On Tue, 13 Mar 2018 18:25:58 +0530
Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxxxxxxx> wrote:
> -static inline struct map_info *free_map_info(struct map_info *info)
> +static inline struct uprobe_map_info *
> +uprobe_free_map_info(struct uprobe_map_info *info)
> {
> - struct map_info *next = info->next;
> + struct uprobe_map_info *next = info->next;
> kfree(info);
> return next;
> }
>
> -static struct map_info *
> -build_map_info(struct address_space *mapping, loff_t offset, bool is_register)
> +static struct uprobe_map_info *
> +uprobe_build_map_info(struct address_space *mapping, loff_t offset,

Also, as these functions have side effects (like you need to perform a
mmput(info->mm), you need to add kerneldoc type comments to these
functions, explaining how to use them.

When you upgrade a function from static to use cases outside the file,
it requires documenting that function for future users.

-- Steve


> + bool is_register)
> {
> unsigned long pgoff = offset >> PAGE_SHIFT;
> struct vm_area_struct *vma;
> - struct map_info *curr = NULL;
> - struct map_info *prev = NULL;
> - struct map_info *info;
> + struct uprobe_map_info *curr = NULL;
> + struct uprobe_map_info *prev = NULL;
> + struct uprobe_map_info *info;
> int more = 0;
>
> again:
> @@ -729,7 +731,7 @@ static inline struct map_info *free_map_info(struct map_info *info)
> * Needs GFP_NOWAIT to avoid i_mmap_rwsem recursion through
> * reclaim. This is optimistic, no harm done if it fails.
> */
> - prev = kmalloc(sizeof(struct map_info),
> + prev = kmalloc(sizeof(struct uprobe_map_info),
> GFP_NOWAIT | __GFP_NOMEMALLOC | __GFP_NOWARN);
> if (prev)
> prev->next = NULL;
> @@ -762,7 +764,7 @@ static inline struct map_info *free_map_info(struct map_info *info)
> }
>
> do {
> - info = kmalloc(sizeof(struct map_info), GFP_KERNEL);
> + info = kmalloc(sizeof(struct uprobe_map_info), GFP_KERNEL);
> if (!info) {
> curr = ERR_PTR(-ENOMEM);
> goto out;
> @@ -774,7 +776,7 @@ static inline struct map_info *free_map_info(struct map_info *info)
> goto again;
> out:
> while (prev)
> - prev = free_map_info(prev);
> + prev = uprobe_free_map_info(prev);
> return curr;
> }
>
> @@ -782,11 +784,11 @@ static inline struct map_info *free_map_info(struct map_info *info)
> register_for_each_vma(struct uprobe *uprobe, struct uprobe_consumer *new)
> {
> bool is_register = !!new;
> - struct map_info *info;
> + struct uprobe_map_info *info;
> int err = 0;
>
> percpu_down_write(&dup_mmap_sem);
> - info = build_map_info(uprobe->inode->i_mapping,
> + info = uprobe_build_map_info(uprobe->inode->i_mapping,
> uprobe->offset, is_register);
> if (IS_ERR(info)) {
> err = PTR_ERR(info);
> @@ -825,7 +827,7 @@ static inline struct map_info *free_map_info(struct map_info *info)
> up_write(&mm->mmap_sem);
> free:
> mmput(mm);
> - info = free_map_info(info);
> + info = uprobe_free_map_info(info);
> }
> out:
> percpu_up_write(&dup_mmap_sem);