Hello !
The attached patch incorporates preemption enable/disable in some parts
of the kernel. I have tested this on the Broadcom Sibyte. Please review
...
Thanks
Manish Lachwani
Index: linux-2.6.8.1/arch/mips/kernel/signal32.c
===================================================================
--- linux-2.6.8.1.orig/arch/mips/kernel/signal32.c
+++ linux-2.6.8.1/arch/mips/kernel/signal32.c
@@ -295,6 +295,8 @@
err |= __get_user(current->used_math, &sc->sc_used_math);
+ preempt_disable();
+
if (current->used_math) {
/* restore fpu context if we have used it before */
own_fpu();
@@ -304,6 +306,8 @@
lose_fpu();
}
+ preempt_enable();
+
return err;
}
@@ -489,12 +493,16 @@
* Save FPU state to signal context. Signal handler will "inherit"
* current FPU state.
*/
+ preempt_disable();
+
if (!is_fpu_owner()) {
own_fpu();
restore_fp(current);
}
err |= save_fp_context32(sc);
+ preempt_enable();
+
out:
return err;
}
Index: linux-2.6.8.1/arch/mips/mm/c-sb1.c
===================================================================
--- linux-2.6.8.1.orig/arch/mips/mm/c-sb1.c
+++ linux-2.6.8.1/arch/mips/mm/c-sb1.c
@@ -197,10 +197,14 @@
if (!(vma->vm_flags & VM_EXEC))
return;
+ preempt_disable();
+
addr &= PAGE_MASK;
args.vma = vma;
args.addr = addr;
on_each_cpu(sb1_flush_cache_page_ipi, (void *) &args, 1, 1);
+
+ preempt_enable();
}
#else
void sb1_flush_cache_page(struct vm_area_struct *vma, unsigned long
addr)
@@ -243,7 +247,9 @@
static void sb1___flush_cache_all(void)
{
+ preempt_disable();
on_each_cpu(sb1___flush_cache_all_ipi, 0, 1, 1);
+ preempt_enable();
}
#else
void sb1___flush_cache_all(void)
@@ -291,9 +297,13 @@
{
struct flush_icache_range_args args;
+ preempt_disable();
+
args.start = start;
args.end = end;
on_each_cpu(sb1_flush_icache_range_ipi, &args, 1, 1);
+
+ preempt_enable();
}
#else
void sb1_flush_icache_range(unsigned long start, unsigned long end)
@@ -348,9 +358,14 @@
if (!(vma->vm_flags & VM_EXEC))
return;
+
+ preempt_disable();
+
args.vma = vma;
args.page = page;
on_each_cpu(sb1_flush_icache_page_ipi, (void *) &args, 1, 1);
+
+ preempt_enable();
}
#else
void sb1_flush_icache_page(struct vm_area_struct *vma, struct page
*page)
@@ -377,7 +392,9 @@
static void sb1_flush_cache_sigtramp(unsigned long addr)
{
+ preempt_disable();
on_each_cpu(sb1_flush_cache_sigtramp_ipi, (void *) addr, 1, 1);
+ preempt_enable();
}
#else
void sb1_flush_cache_sigtramp(unsigned long addr)
Index: linux-2.6.8.1/arch/mips/mm/tlb-sb1.c
===================================================================
--- linux-2.6.8.1.orig/arch/mips/mm/tlb-sb1.c
+++ linux-2.6.8.1/arch/mips/mm/tlb-sb1.c
@@ -286,10 +286,17 @@
these entries, we just bump the asid. */
void local_flush_tlb_mm(struct mm_struct *mm)
{
- int cpu = smp_processor_id();
+ int cpu;
+
+ preempt_disable();
+
+ cpu = smp_processor_id();
+
if (cpu_context(cpu, mm) != 0) {
drop_mmu_context(mm, cpu);
}
+
+ preempt_enable();
}
/* Stolen from mips32 routines */
Index: linux-2.6.8.1/arch/mips/kernel/traps.c
===================================================================
--- linux-2.6.8.1.orig/arch/mips/kernel/traps.c
+++ linux-2.6.8.1/arch/mips/kernel/traps.c
@@ -411,6 +411,8 @@
goto sig;
}
+ preempt_disable();
+
if (ll_task == NULL || ll_task == current) {
ll_bit = 1;
} else {
@@ -418,6 +420,8 @@
}
ll_task = current;
+ preempt_enable();
+
regs->regs[(opcode & RT) >> 16] = value;
compute_return_epc(regs);
@@ -450,12 +454,18 @@
signal = SIGBUS;
goto sig;
}
+
+ preempt_disable();
+
if (ll_bit == 0 || ll_task != current) {
regs->regs[reg] = 0;
+ preempt_enable();
compute_return_epc(regs);
return;
}
+ preempt_enable();
+
if (put_user(regs->regs[reg], vaddr)) {
signal = SIGSEGV;
goto sig;
@@ -515,6 +525,8 @@
if (fcr31 & FPU_CSR_UNI_X) {
int sig;
+ preempt_disable();
+
/*
* Unimplemented operation exception. If we've got the full
* software emulator on-board, let's use it...
@@ -540,6 +552,8 @@
/* Restore the hardware register state */
restore_fp(current);
+ preempt_enable();
+
/* If something went wrong, signal */
if (sig)
force_sig(sig, current);
@@ -659,6 +673,8 @@
break;
case 1:
+ preempt_disable();
+
own_fpu();
if (current->used_math) { /* Using the FPU again. */
restore_fp(current);
@@ -674,6 +690,8 @@
force_sig(sig, current);
}
+ preempt_enable();
+
return;
case 2:
Index: linux-2.6.8.1/arch/mips/kernel/process.c
===================================================================
--- linux-2.6.8.1.orig/arch/mips/kernel/process.c
+++ linux-2.6.8.1/arch/mips/kernel/process.c
@@ -99,10 +99,14 @@
childksp = (unsigned long)ti + THREAD_SIZE - 32;
+ preempt_disable();
+
if (is_fpu_owner()) {
save_fp(p);
}
+ preempt_enable();
+
/* set up new TSS. */
childregs = (struct pt_regs *) childksp - 1;
*childregs = *regs;
Index: linux-2.6.8.1/arch/mips/kernel/signal.c
===================================================================
--- linux-2.6.8.1.orig/arch/mips/kernel/signal.c
+++ linux-2.6.8.1/arch/mips/kernel/signal.c
@@ -178,6 +178,8 @@
err |= __get_user(current->used_math, &sc->sc_used_math);
+ preempt_disable();
+
if (current->used_math) {
/* restore fpu context if we have used it before */
own_fpu();
@@ -187,6 +189,8 @@
lose_fpu();
}
+ preempt_enable();
+
return err;
}
@@ -320,12 +324,16 @@
* Save FPU state to signal context. Signal handler will "inherit"
* current FPU state.
*/
+ preempt_disable();
+
if (!is_fpu_owner()) {
own_fpu();
restore_fp(current);
}
err |= save_fp_context(sc);
+ preempt_enable();
+
out:
return err;
}
