From: Eric Dumazet Date: Tue, 8 May 2007 07:26:15 +0000 (-0700) Subject: procfs: reorder struct pid_dentry to save space on 64bit archs, and constify them X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=c5141e6d64ab5c48a5e31413c7a6cdda84ac1d52;p=openwrt%2Fstaging%2Fblogic.git procfs: reorder struct pid_dentry to save space on 64bit archs, and constify them Change the order of fields of struct pid_entry (file fs/proc/base.c) in order to avoid a hole on 64bit archs. (8 bytes saved per object) Also change all pid_entry arrays to be const qualified, to make clear they must not be modified. Before (on x86_64) : # size fs/proc/base.o text data bss dec hex filename 15549 2192 0 17741 454d fs/proc/base.o After : # size fs/proc/base.o text data bss dec hex filename 17229 176 0 17405 43fd fs/proc/base.o Thats 336 bytes saved on kernel size on x86_64 Signed-off-by: Eric Dumazet Acked-by: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/proc/base.c b/fs/proc/base.c index 17f7a7ee6c5e..be94ddebb413 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -91,8 +91,8 @@ #define PROC_NUMBUF 13 struct pid_entry { - int len; char *name; + int len; mode_t mode; const struct inode_operations *iop; const struct file_operations *fop; @@ -100,8 +100,8 @@ struct pid_entry { }; #define NOD(NAME, MODE, IOP, FOP, OP) { \ - .len = sizeof(NAME) - 1, \ .name = (NAME), \ + .len = sizeof(NAME) - 1, \ .mode = MODE, \ .iop = IOP, \ .fop = FOP, \ @@ -1159,7 +1159,8 @@ static struct dentry_operations pid_dentry_operations = /* Lookups */ -typedef struct dentry *instantiate_t(struct inode *, struct dentry *, struct task_struct *, void *); +typedef struct dentry *instantiate_t(struct inode *, struct dentry *, + struct task_struct *, const void *); /* * Fill a directory entry. @@ -1175,7 +1176,7 @@ typedef struct dentry *instantiate_t(struct inode *, struct dentry *, struct tas */ static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, char *name, int len, - instantiate_t instantiate, struct task_struct *task, void *ptr) + instantiate_t instantiate, struct task_struct *task, const void *ptr) { struct dentry *child, *dir = filp->f_path.dentry; struct inode *inode; @@ -1310,9 +1311,9 @@ static struct dentry_operations tid_fd_dentry_operations = }; static struct dentry *proc_fd_instantiate(struct inode *dir, - struct dentry *dentry, struct task_struct *task, void *ptr) + struct dentry *dentry, struct task_struct *task, const void *ptr) { - unsigned fd = *(unsigned *)ptr; + unsigned fd = *(const unsigned *)ptr; struct file *file; struct files_struct *files; struct inode *inode; @@ -1478,9 +1479,9 @@ static const struct inode_operations proc_fd_inode_operations = { }; static struct dentry *proc_pident_instantiate(struct inode *dir, - struct dentry *dentry, struct task_struct *task, void *ptr) + struct dentry *dentry, struct task_struct *task, const void *ptr) { - struct pid_entry *p = ptr; + const struct pid_entry *p = ptr; struct inode *inode; struct proc_inode *ei; struct dentry *error = ERR_PTR(-EINVAL); @@ -1509,13 +1510,13 @@ out: static struct dentry *proc_pident_lookup(struct inode *dir, struct dentry *dentry, - struct pid_entry *ents, + const struct pid_entry *ents, unsigned int nents) { struct inode *inode; struct dentry *error; struct task_struct *task = get_proc_task(dir); - struct pid_entry *p, *last; + const struct pid_entry *p, *last; error = ERR_PTR(-ENOENT); inode = NULL; @@ -1544,8 +1545,8 @@ out_no_task: return error; } -static int proc_pident_fill_cache(struct file *filp, void *dirent, filldir_t filldir, - struct task_struct *task, struct pid_entry *p) +static int proc_pident_fill_cache(struct file *filp, void *dirent, + filldir_t filldir, struct task_struct *task, const struct pid_entry *p) { return proc_fill_cache(filp, dirent, filldir, p->name, p->len, proc_pident_instantiate, task, p); @@ -1553,14 +1554,14 @@ static int proc_pident_fill_cache(struct file *filp, void *dirent, filldir_t fil static int proc_pident_readdir(struct file *filp, void *dirent, filldir_t filldir, - struct pid_entry *ents, unsigned int nents) + const struct pid_entry *ents, unsigned int nents) { int i; int pid; struct dentry *dentry = filp->f_path.dentry; struct inode *inode = dentry->d_inode; struct task_struct *task = get_proc_task(inode); - struct pid_entry *p, *last; + const struct pid_entry *p, *last; ino_t ino; int ret; @@ -1675,7 +1676,7 @@ static const struct file_operations proc_pid_attr_operations = { .write = proc_pid_attr_write, }; -static struct pid_entry attr_dir_stuff[] = { +static const struct pid_entry attr_dir_stuff[] = { REG("current", S_IRUGO|S_IWUGO, pid_attr), REG("prev", S_IRUGO, pid_attr), REG("exec", S_IRUGO|S_IWUGO, pid_attr), @@ -1741,7 +1742,7 @@ static const struct inode_operations proc_self_inode_operations = { * that properly belong to the /proc filesystem, as they describe * describe something that is process related. */ -static struct pid_entry proc_base_stuff[] = { +static const struct pid_entry proc_base_stuff[] = { NOD("self", S_IFLNK|S_IRWXUGO, &proc_self_inode_operations, NULL, {}), }; @@ -1770,9 +1771,9 @@ static struct dentry_operations proc_base_dentry_operations = }; static struct dentry *proc_base_instantiate(struct inode *dir, - struct dentry *dentry, struct task_struct *task, void *ptr) + struct dentry *dentry, struct task_struct *task, const void *ptr) { - struct pid_entry *p = ptr; + const struct pid_entry *p = ptr; struct inode *inode; struct proc_inode *ei; struct dentry *error = ERR_PTR(-EINVAL); @@ -1820,7 +1821,7 @@ static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) { struct dentry *error; struct task_struct *task = get_proc_task(dir); - struct pid_entry *p, *last; + const struct pid_entry *p, *last; error = ERR_PTR(-ENOENT); @@ -1846,8 +1847,8 @@ out_no_task: return error; } -static int proc_base_fill_cache(struct file *filp, void *dirent, filldir_t filldir, - struct task_struct *task, struct pid_entry *p) +static int proc_base_fill_cache(struct file *filp, void *dirent, + filldir_t filldir, struct task_struct *task, const struct pid_entry *p) { return proc_fill_cache(filp, dirent, filldir, p->name, p->len, proc_base_instantiate, task, p); @@ -1884,7 +1885,7 @@ static int proc_pid_io_accounting(struct task_struct *task, char *buffer) static const struct file_operations proc_task_operations; static const struct inode_operations proc_task_inode_operations; -static struct pid_entry tgid_base_stuff[] = { +static const struct pid_entry tgid_base_stuff[] = { DIR("task", S_IRUGO|S_IXUGO, task), DIR("fd", S_IRUSR|S_IXUSR, fd), INF("environ", S_IRUSR, pid_environ), @@ -2027,7 +2028,7 @@ out: static struct dentry *proc_pid_instantiate(struct inode *dir, struct dentry * dentry, - struct task_struct *task, void *ptr) + struct task_struct *task, const void *ptr) { struct dentry *error = ERR_PTR(-ENOENT); struct inode *inode; @@ -2142,7 +2143,7 @@ int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) goto out_no_task; for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { - struct pid_entry *p = &proc_base_stuff[nr]; + const struct pid_entry *p = &proc_base_stuff[nr]; if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) goto out; } @@ -2168,7 +2169,7 @@ out_no_task: /* * Tasks */ -static struct pid_entry tid_base_stuff[] = { +static const struct pid_entry tid_base_stuff[] = { DIR("fd", S_IRUSR|S_IXUSR, fd), INF("environ", S_IRUSR, pid_environ), INF("auxv", S_IRUSR, pid_auxv), @@ -2238,7 +2239,7 @@ static const struct inode_operations proc_tid_base_inode_operations = { }; static struct dentry *proc_task_instantiate(struct inode *dir, - struct dentry *dentry, struct task_struct *task, void *ptr) + struct dentry *dentry, struct task_struct *task, const void *ptr) { struct dentry *error = ERR_PTR(-ENOENT); struct inode *inode;