Re: 2.5.73-mm2
From: William Lee Irwin III <hidden>
Date: 2003-06-28 08:42:45
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On Fri, Jun 27, 2003 at 08:21:30PM -0700, Andrew Morton wrote:
ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.5/2.5.73/2.5.73-mm2/ Just bits and pieces.
This could almost be sent through rusty, but I think in general BKL removal patches should go through whatever ringer -mm et al provide. -- wli Remove spurious BKL acquisitions in /proc/. The BKL is not required to access nr_threads for reporting, and get_locks_status() takes it internally, wrapping all operations with it. diff -prauN wli-2.5.73-3/fs/proc/proc_misc.c wli-2.5.73-4/fs/proc/proc_misc.c
--- wli-2.5.73-3/fs/proc/proc_misc.c 2003-06-23 10:29:54.000000000 -0700
+++ wli-2.5.73-4/fs/proc/proc_misc.c 2003-06-23 10:32:25.000000000 -0700@@ -497,11 +497,10 @@ static int ds1286_read_proc(char *page, static int locks_read_proc(char *page, char **start, off_t off, int count, int *eof, void *data) { - int len; - lock_kernel(); - len = get_locks_status(page, start, off, count); - unlock_kernel(); - if (len < count) *eof = 1; + int len = get_locks_status(page, start, off, count); + + if (len < count) + *eof = 1; return len; }
diff -prauN wli-2.5.73-3/fs/proc/root.c wli-2.5.73-4/fs/proc/root.c
--- wli-2.5.73-3/fs/proc/root.c 2003-06-22 11:33:07.000000000 -0700
+++ wli-2.5.73-4/fs/proc/root.c 2003-06-23 10:32:25.000000000 -0700@@ -81,11 +81,13 @@ void __init proc_root_init(void) static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry) { - if (dir->i_ino == PROC_ROOT_INO) { /* check for safety... */ - lock_kernel(); + /* + * nr_threads is actually protected by the tasklist_lock; + * however, it's conventional to do reads, especially for + * reporting, without any locking whatsoever. + */ + if (dir->i_ino == PROC_ROOT_INO) /* check for safety... */ dir->i_nlink = proc_root.nlink + nr_threads; - unlock_kernel(); - } if (!proc_lookup(dir, dentry)) { return NULL; --
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