lkml.org 
[lkml]   [2008]   [Jul]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 1/2][RT] powerpc - XICS: move the call to irq_radix_revmap from xics_startup to xics_host_map
From: Sebastien Dugue <sebastien.dugue@bull.net>
Date: Tue, 22 Jul 2008 13:05:24 +0200
Subject: [PATCH][RT] powerpc - XICS: move the call to irq_radix_revmap from xics_startup to xics_host_map

This patch moves the insertion of an irq into the reverse mapping radix tree
from xics_startup() into xics_host_map().

The reason for this change is that xics_startup() is called with preemption
disabled (which is not the case for xics_host_map()) which is a problem under a
preempt-rt kernel as we cannot even allocate GFP_ATOMIC memory for the radix tree
nodes.


Signed-off-by: Sebastien Dugue <sebastien.dugue@bull.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <michael@ellerman.id.au>

---
arch/powerpc/platforms/pseries/xics.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)

Index: linux-2.6.25.8-rt7/arch/powerpc/platforms/pseries/xics.c
===================================================================
--- linux-2.6.25.8-rt7.orig/arch/powerpc/platforms/pseries/xics.c
+++ linux-2.6.25.8-rt7/arch/powerpc/platforms/pseries/xics.c
@@ -311,12 +311,6 @@ static void xics_mask_irq(unsigned int v

static unsigned int xics_startup(unsigned int virq)
{
- unsigned int irq;
-
- /* force a reverse mapping of the interrupt so it gets in the cache */
- irq = (unsigned int)irq_map[virq].hwirq;
- irq_radix_revmap(xics_host, irq);
-
/* unmask it */
xics_unmask_irq(virq);
return 0;
@@ -529,8 +523,14 @@ static int xics_host_match(struct irq_ho
static int xics_host_map_direct(struct irq_host *h, unsigned int virq,
irq_hw_number_t hw)
{
+ unsigned int irq;
+
pr_debug("xics: map_direct virq %d, hwirq 0x%lx\n", virq, hw);

+ /* force a reverse mapping of the interrupt so it gets in the cache */
+ irq = (unsigned int)irq_map[virq].hwirq;
+ irq_radix_revmap(xics_host, irq);
+
get_irq_desc(virq)->status |= IRQ_LEVEL;
set_irq_chip_and_handler(virq, &xics_pic_direct, handle_fasteoi_irq);
return 0;
@@ -539,8 +539,14 @@ static int xics_host_map_direct(struct i
static int xics_host_map_lpar(struct irq_host *h, unsigned int virq,
irq_hw_number_t hw)
{
+ unsigned int irq;
+
pr_debug("xics: map_direct virq %d, hwirq 0x%lx\n", virq, hw);

+ /* force a reverse mapping of the interrupt so it gets in the cache */
+ irq = (unsigned int)irq_map[virq].hwirq;
+ irq_radix_revmap(xics_host, irq);
+
get_irq_desc(virq)->status |= IRQ_LEVEL;
set_irq_chip_and_handler(virq, &xics_pic_lpar, handle_fasteoi_irq);
return 0;

\
 
 \ /
  Last update: 2008-07-24 12:55    [W:0.218 / U:0.264 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site