Re: [PATCH][2.6.7-rc3-mm1] perfctr cpumask cleanup

[Paul Jackson]

> Clean up perfctr/virtual by using the new cpus_andnot() operation

Neat.

Do you still need "tmp" ?  Perhaps you could further add the
following patch (untested, unbuilt, ...).

This saves copies and stack space for one cpumask (that's
512 bits on my SN2 systems).

Signed-off-by: Paul Jackson <pj@xxxxxxx>

Index: 2.6.7-rc3-mm1/drivers/perfctr/virtual.c
===================================================================
--- 2.6.7-rc3-mm1.orig/drivers/perfctr/virtual.c	2004-06-09 15:34:34.000000000 -0700
+++ 2.6.7-rc3-mm1/drivers/perfctr/virtual.c	2004-06-09 15:38:32.000000000 -0700
@@ -403,11 +403,10 @@
 		return -EFAULT;
 
 	if (control.cpu_control.nractrs || control.cpu_control.nrictrs) {
-		cpumask_t tmp, old_mask, new_mask;
+		cpumask_t old_mask, new_mask;
 
-		tmp = perfctr_cpus_forbidden_mask;
 		old_mask = tsk->cpus_allowed;
-		cpus_andnot(new_mask, old_mask, tmp);
+		cpus_andnot(new_mask, old_mask, perfctr_cpus_forbidden_mask);
 
 		if (cpus_empty(new_mask))
 			return -EINVAL;


-- 
                          I won't rest till it's the best ...
                          Programmer, Linux Scalability
                          Paul Jackson <pj@xxxxxxx> 1.650.933.1373
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