On 11/2/21 8:40 AM, zhangyiru wrote:
> commit 21a3c273f88c9cbbaf7e ("mm, hugetlb: add thread name and pid to
> SHM_HUGETLB mlock rlimit warning") marked this as deprecated in 2012,
> but it is not deleted yet.
>
> Mike says he still see that message in log files on occasion,
> so maybe we should preserve this warning.
>
> Also remove hugetlbfs related user_shm_unlock in ipc/shm.c and remove
> the user_shm_unlock after out.
>
> Signed-off-by: zhangyiru <zhangyiru3@xxxxxxxxxx>
> ---
> Changelog:
> v7: modify ucounts definition and remove the user_shm_unlock after out
> v6: fix errors in v5 and remove hugetlbfs related user_shm_unlock in
> ipc/shm.c
> v5: delete ucounts variable, and function calls that use ucounts in
> additon
> v4: modify context information of obsolete
> v3: modify warning message to obsolete
> v2: preserve warning message
> v1: remove mlock ulimit for SHM_HUGETLB
> ---
> fs/hugetlbfs/inode.c | 23 ++++++++---------------
> include/linux/hugetlb.h | 3 +--
> ipc/shm.c | 8 +-------
> mm/memfd.c | 4 +---
> mm/mmap.c | 3 +--
> 5 files changed, 12 insertions(+), 29 deletions(-)
Thanks for continuing to make updates.
I think the use of user_shm_lock/unlock as done below to check for
potential users of the obsolete feature is the simplest thing to do.
If Hugh or someone else has another opinion, please speak up.
> diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
> index cdfb1ae78a3f..49d2e686be74 100644
> --- a/fs/hugetlbfs/inode.c
> +++ b/fs/hugetlbfs/inode.c
> @@ -1446,8 +1446,8 @@ static int get_hstate_idx(int page_size_log)
> * otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
> */
> struct file *hugetlb_file_setup(const char *name, size_t size,
> - vm_flags_t acctflag, struct ucounts **ucounts,
> - int creat_flags, int page_size_log)
> + vm_flags_t acctflag, int creat_flags,
> + int page_size_log)
> {
> struct inode *inode;
> struct vfsmount *mnt;
> @@ -1458,22 +1458,19 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
> if (hstate_idx < 0)
> return ERR_PTR(-ENODEV);
>
> - *ucounts = NULL;
> mnt = hugetlbfs_vfsmount[hstate_idx];
> if (!mnt)
> return ERR_PTR(-ENOENT);
>
> if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) {
> - *ucounts = current_ucounts();
> - if (user_shm_lock(size, *ucounts)) {
> - task_lock(current);
> - pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is deprecated\n",
> + struct ucounts *ucounts = current_ucounts();
> +
> + if (user_shm_lock(size, ucounts)) {
> + pr_warn_once("%s (%d): Using mlock ulimits for SHM_HUGETLB is obsolete\n",
> current->comm, current->pid);
> - task_unlock(current);
> - } else {
> - *ucounts = NULL;
> - return ERR_PTR(-EPERM);
> + user_shm_unlock(size, ucounts);
> }
> + return ERR_PTR(-EPERM);
> }
>
> file = ERR_PTR(-ENOSPC);
> @@ -1498,10 +1495,6 @@ struct file *hugetlb_file_setup(const char *name, size_t size,
>
> iput(inode);
> out:
> - if (*ucounts) {
> - user_shm_unlock(size, *ucounts);
> - *ucounts = NULL;
> - }
> return file;
> }
>
> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
> index f7ca1a3870ea..e8e033b74b7e 100644
> --- a/include/linux/hugetlb.h
> +++ b/include/linux/hugetlb.h
> @@ -468,8 +468,7 @@ static inline struct hugetlbfs_inode_info *HUGETLBFS_I(struct inode *inode)
> extern const struct file_operations hugetlbfs_file_operations;
> extern const struct vm_operations_struct hugetlb_vm_ops;
> struct file *hugetlb_file_setup(const char *name, size_t size, vm_flags_t acct,
> - struct ucounts **ucounts, int creat_flags,
> - int page_size_log);
> + int creat_flags, int page_size_log);
>
> static inline bool is_file_hugepages(struct file *file)
> {
You forgot to make the same change to the !CONFIG_HUGETLBFS version of
hugetlb_file_setup() within include/linux/hugetlb.h.
The rest of the changes look good to me.
--
Mike Kravetz
