Re: mem=16MB laptop testing

From: Andrew Morton (akpm_at_osdl.org)
Date: 10/15/03

  • Next message: Neil Brown: "Strange dcache memory pressure when highmem enabled"
    Date:	Tue, 14 Oct 2003 21:31:50 -0700
    To: William Lee Irwin III <wli@holomorphy.com>
    
    

    William Lee Irwin III <wli@holomorphy.com> wrote:
    >
    > (e) About 4.8MB are consumed by slab allocations at runtime.
    > The top 10 slab abusers are:
    >
    > inode_cache 840K 840K 100.00%
    > dentry_cache 746K 753K 99.07%
    > ext3_inode_cache 591K 592K 99.84%
    > size-4096 504K 504K 100.00%
    > size-512 203K 204K 99.75%
    > size-2048 182K 204K 89.22%
    > pgd 188K 188K 100.00%
    > task_struct 100K 108K 92.86%
    > vm_area_struct 93K 101K 92.28%
    > blkdev_requests 101K 101K 100.00%
    >
    > The inode_cache culprit is the obvious *** of many complaints:
    > # find /sys | wc -l
    > 2656
    >

    hmm, you have a lot more sysfs entries than I do:

    vmm:/home/akpm> find /sys|wc -l
        849

    The below patch nukes them all; saves around half meg here. You need to
    add "nosysfs" and "root=NN:MM" to the kernel boot commandline. Please let
    me know how much space you save.

     fs/sysfs/bin.c | 6 ++++++
     fs/sysfs/dir.c | 16 +++++++++++++++-
     fs/sysfs/file.c | 9 +++++++++
     fs/sysfs/group.c | 6 ++++++
     fs/sysfs/inode.c | 18 ++++++++++++++++--
     fs/sysfs/symlink.c | 3 +++
     fs/sysfs/sysfs.h | 3 +++
     include/linux/sysfs.h | 0
     8 files changed, 58 insertions(+), 3 deletions(-)

    diff -puN fs/sysfs/inode.c~nosysfs fs/sysfs/inode.c
    --- 25/fs/sysfs/inode.c~nosysfs 2003-10-14 18:24:42.000000000 -0700
    +++ 25-akpm/fs/sysfs/inode.c 2003-10-14 18:40:16.000000000 -0700
    @@ -11,7 +11,8 @@
     #include <linux/pagemap.h>
     #include <linux/namei.h>
     #include <linux/backing-dev.h>
    -extern struct super_block * sysfs_sb;
    +#include <linux/init.h>
    +#include "sysfs.h"
     
     static struct address_space_operations sysfs_aops = {
             .readpage = simple_readpage,
    @@ -24,6 +25,8 @@ static struct backing_dev_info sysfs_bac
             .memory_backed = 1, /* Does not contribute to dirty memory */
     };
     
    +int nosysfs;
    +
     struct inode * sysfs_new_inode(mode_t mode)
     {
             struct inode * inode = new_inode(sysfs_sb);
    @@ -44,6 +47,10 @@ int sysfs_create(struct dentry * dentry,
     {
             int error = 0;
             struct inode * inode = NULL;
    +
    + if (nosysfs)
    + return 0;
    +
             if (dentry) {
                     if (!dentry->d_inode) {
                             if ((inode = sysfs_new_inode(mode)))
    @@ -87,6 +94,8 @@ void sysfs_hash_and_remove(struct dentry
     {
             struct dentry * victim;
     
    + if (nosysfs)
    + return;
             down(&dir->d_inode->i_sem);
             victim = sysfs_get_dentry(dir,name);
             if (!IS_ERR(victim)) {
    @@ -107,4 +116,9 @@ void sysfs_hash_and_remove(struct dentry
             up(&dir->d_inode->i_sem);
     }
     
    -
    +static int __init nosysfs_setup(char *str)
    +{
    + nosysfs = 1;
    + return 1;
    +}
    +__setup("nosysfs", nosysfs_setup);
    diff -puN fs/sysfs/dir.c~nosysfs fs/sysfs/dir.c
    --- 25/fs/sysfs/dir.c~nosysfs 2003-10-14 18:25:40.000000000 -0700
    +++ 25-akpm/fs/sysfs/dir.c 2003-10-14 18:29:50.000000000 -0700
    @@ -46,6 +46,8 @@ static int create_dir(struct kobject * k
     
     int sysfs_create_subdir(struct kobject * k, const char * n, struct dentry ** d)
     {
    + if (nosysfs)
    + return 0;
             return create_dir(k,k->dentry,n,d);
     }
     
    @@ -61,6 +63,9 @@ int sysfs_create_dir(struct kobject * ko
             struct dentry * parent;
             int error = 0;
     
    + if (nosysfs)
    + return 0;
    +
             if (!kobj)
                     return -EINVAL;
     
    @@ -102,6 +107,8 @@ static void remove_dir(struct dentry * d
     
     void sysfs_remove_subdir(struct dentry * d)
     {
    + if (nosysfs)
    + return;
             remove_dir(d);
     }
     
    @@ -118,8 +125,12 @@ void sysfs_remove_subdir(struct dentry *
     void sysfs_remove_dir(struct kobject * kobj)
     {
             struct list_head * node;
    - struct dentry * dentry = dget(kobj->dentry);
    + struct dentry *dentry;
    +
    + if (nosysfs)
    + return;
     
    + dentry = dget(kobj->dentry);
             if (!dentry)
                     return;
     
    @@ -164,6 +175,9 @@ void sysfs_rename_dir(struct kobject * k
     {
             struct dentry * new_dentry, * parent;
     
    + if (nosysfs)
    + return;
    +
             if (!strcmp(kobject_name(kobj), new_name))
                     return;
     
    diff -puN include/linux/sysfs.h~nosysfs include/linux/sysfs.h
    diff -puN fs/sysfs/sysfs.h~nosysfs fs/sysfs/sysfs.h
    --- 25/fs/sysfs/sysfs.h~nosysfs 2003-10-14 18:27:36.000000000 -0700
    +++ 25-akpm/fs/sysfs/sysfs.h 2003-10-14 18:28:22.000000000 -0700
    @@ -1,4 +1,7 @@
    +struct super_block;
     
    +extern struct super_block *sysfs_sb;
    +extern int nosysfs;
     extern struct vfsmount * sysfs_mount;
     
     extern struct inode * sysfs_new_inode(mode_t mode);
    diff -puN fs/sysfs/file.c~nosysfs fs/sysfs/file.c
    --- 25/fs/sysfs/file.c~nosysfs 2003-10-14 18:38:15.000000000 -0700
    +++ 25-akpm/fs/sysfs/file.c 2003-10-14 18:40:06.000000000 -0700
    @@ -350,6 +350,9 @@ int sysfs_add_file(struct dentry * dir,
             struct dentry * dentry;
             int error;
     
    + if (nosysfs)
    + return 0;
    +
             down(&dir->d_inode->i_sem);
             dentry = sysfs_get_dentry(dir,attr->name);
             if (!IS_ERR(dentry)) {
    @@ -374,6 +377,9 @@ int sysfs_add_file(struct dentry * dir,
     
     int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
     {
    + if (nosysfs)
    + return 0;
    +
             if (kobj && attr)
                     return sysfs_add_file(kobj->dentry,attr);
             return -EINVAL;
    @@ -394,6 +400,9 @@ int sysfs_update_file(struct kobject * k
             struct dentry * victim;
             int res = -ENOENT;
     
    + if (nosysfs)
    + return 0;
    +
             down(&dir->d_inode->i_sem);
             victim = sysfs_get_dentry(dir, attr->name);
             if (!IS_ERR(victim)) {
    diff -puN fs/sysfs/symlink.c~nosysfs fs/sysfs/symlink.c
    --- 25/fs/sysfs/symlink.c~nosysfs 2003-10-14 18:40:32.000000000 -0700
    +++ 25-akpm/fs/sysfs/symlink.c 2003-10-14 18:40:57.000000000 -0700
    @@ -79,6 +79,9 @@ int sysfs_create_link(struct kobject * k
             char * path;
             char * s;
     
    + if (nosysfs)
    + return 0;
    +
             depth = object_depth(kobj);
             size = object_path_length(target) + depth * 3 - 1;
             if (size > PATH_MAX)
    diff -puN fs/sysfs/bin.c~nosysfs fs/sysfs/bin.c
    --- 25/fs/sysfs/bin.c~nosysfs 2003-10-14 18:51:48.000000000 -0700
    +++ 25-akpm/fs/sysfs/bin.c 2003-10-14 18:52:20.000000000 -0700
    @@ -152,6 +152,9 @@ int sysfs_create_bin_file(struct kobject
             struct dentry * parent;
             int error = 0;
     
    + if (nosysfs)
    + return 0;
    +
             if (!kobj || !attr)
                     return -EINVAL;
     
    @@ -185,6 +188,9 @@ int sysfs_create_bin_file(struct kobject
     
     int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
     {
    + if (nosysfs)
    + return 0;
    +
             sysfs_hash_and_remove(kobj->dentry,attr->attr.name);
             return 0;
     }
    diff -puN fs/sysfs/group.c~nosysfs fs/sysfs/group.c
    --- 25/fs/sysfs/group.c~nosysfs 2003-10-14 19:32:58.000000000 -0700
    +++ 25-akpm/fs/sysfs/group.c 2003-10-14 19:33:16.000000000 -0700
    @@ -45,6 +45,9 @@ int sysfs_create_group(struct kobject *
             struct dentry * dir;
             int error;
     
    + if (nosysfs)
    + return 0;
    +
             if (grp->name) {
                     error = sysfs_create_subdir(kobj,grp->name,&dir);
                     if (error)
    @@ -65,6 +68,9 @@ void sysfs_remove_group(struct kobject *
     {
             struct dentry * dir;
     
    + if (nosysfs)
    + return;
    +
             if (grp->name)
                     dir = sysfs_get_dentry(kobj->dentry,grp->name);
             else

    _

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/


  • Next message: Neil Brown: "Strange dcache memory pressure when highmem enabled"