>From 9b7b2bb9b4beeaf2fdb7085be6d8b2892c16751e Mon Sep 17 00:00:00 2001
From: Kevin D. Kissell <kevink@xxxxxxxxxxxxx>
Date: Thu, 11 Sep 2008 15:42:19 +0200
Subject: [PATCH] Fix some holes in the automated FPU affinity logic for SMTC and SMVP.
Signed-off-by: Kevin D. Kissell <kevink@xxxxxxxxxxxxx>
diff --git a/arch/mips/kernel/mips-mt-fpaff.c b/arch/mips/kernel/mips-mt-fpaff.c
index df4d3f2..dc9eb72 100644
--- a/arch/mips/kernel/mips-mt-fpaff.c
+++ b/arch/mips/kernel/mips-mt-fpaff.c
@@ -159,7 +159,7 @@ __setup("fpaff=", fpaff_thresh);
/*
* FPU Use Factor empirically derived from experiments on 34K
*/
-#define FPUSEFACTOR 333
+#define FPUSEFACTOR 2000
static __init int mt_fp_affinity_init(void)
{
diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
index 75277c8..8dd44ea 100644
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -152,22 +152,18 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
*/
p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1);
childregs->cp0_status &= ~(ST0_CU2|ST0_CU1);
+#ifdef CONFIG_MIPS_MT_SMTC
+ /*
+ * SMTC restores TCStatus after Status, and the CU bits
+ * are aliased there.
+ */
+ childregs->cp0_tcstatus &= ~(ST0_CU2|ST0_CU1);
+#endif
+
clear_tsk_thread_flag(p, TIF_USEDFPU);
#ifdef CONFIG_MIPS_MT_FPAFF
clear_tsk_thread_flag(p, TIF_FPUBOUND);
- /*
- * FPU affinity support requires that we be subtle.
- * The basic fork support code will have copied
- * the parent's cpus_allowed set, but what the child
- * needs to inherit is the "user" version, which
- * carries the program/user controlled CPU affinity
- * properties that are supposed to be inherited,
- * but not the transient, overlayed, hardware
- * affinity constraints.
- */
- p->thread.user_cpus_allowed = current->thread.user_cpus_allowed;
- p->cpus_allowed = current->thread.user_cpus_allowed;
#endif /* CONFIG_MIPS_MT_FPAFF */
if (clone_flags & CLONE_SETTLS)
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index f9165d1..0d1329e 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -807,8 +807,10 @@ static void mt_ase_fp_affinity(void)
if (cpus_intersects(current->cpus_allowed, mt_fpu_cpumask)) {
cpumask_t tmask;
- cpus_and(tmask, current->thread.user_cpus_allowed,
- mt_fpu_cpumask);
+ current->thread.user_cpus_allowed
+ = current->cpus_allowed;
+ cpus_and(tmask, current->cpus_allowed,
+ mt_fpu_cpumask);
set_cpus_allowed(current, tmask);
set_thread_flag(TIF_FPUBOUND);
}
--
1.5.3.3
