fs/proc/base.c: save decrement during lookup/readdir in /proc/$PID

Comparison for "<" works equally well as comparison for "<=" but one
SUB/LEA is saved (no, it is not optimised away, at least here).

Link: http://lkml.kernel.org/r/20161122195143.GA29812@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 7c843024b4063662241ddb73cb7540a047014ba1..04a5fcad4c341aeefe9491b5bade96e24bb56581 100644 (file)
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2412,14 +2412,14 @@ static struct dentry *proc_pident_lookup(struct inode *dir,
         * Yes, it does not scale. And it should not. Don't add
         * new entries into /proc/<tgid>/ without very good reasons.
         */
-       last = &ents[nents - 1];
-       for (p = ents; p <= last; p++) {
+       last = &ents[nents];
+       for (p = ents; p < last; p++) {
                if (p->len != dentry->d_name.len)
                        continue;
                if (!memcmp(dentry->d_name.name, p->name, p->len))
                        break;
        }
-       if (p > last)
+       if (p >= last)
                goto out;
 
        error = proc_pident_instantiate(dir, dentry, task, p);
@@ -2444,7 +2444,7 @@ static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
        if (ctx->pos >= nents + 2)
                goto out;
 
-       for (p = ents + (ctx->pos - 2); p <= ents + nents - 1; p++) {
+       for (p = ents + (ctx->pos - 2); p < ents + nents; p++) {
                if (!proc_fill_cache(file, ctx, p->name, p->len,
                                proc_pident_instantiate, task, p))
                        break;