Hi Jiaxun,
+Daniel/Thomas for CLOCKEVENTS
On 13/8/24 11:59, Jiaxun Yang wrote:
This avoids warning:
[ 0.118053] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:283
Caused by get_c0_compare_int on secondary CPU.
We also skipped saving IRQ number to struct clock_event_device *cd as
it's never used by clockevent core, as per comments it's only meant
for "non CPU local devices".
Reported-by: Serge Semin <fancer.lancer@xxxxxxxxx>
Closes: https://lore.kernel.org/linux-mips/6szkkqxpsw26zajwysdrwplpjvhl5abpnmxgu2xuj3dkzjnvsf@4daqrz4mf44k/
Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
---
arch/mips/kernel/cevt-r4k.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)
diff --git a/arch/mips/kernel/cevt-r4k.c b/arch/mips/kernel/cevt-r4k.c
index 368e8475870f..5f6e9e2ebbdb 100644
--- a/arch/mips/kernel/cevt-r4k.c
+++ b/arch/mips/kernel/cevt-r4k.c
@@ -303,13 +303,6 @@ int r4k_clockevent_init(void)
if (!c0_compare_int_usable())
return -ENXIO;
- /*
- * With vectored interrupts things are getting platform specific.
- * get_c0_compare_int is a hook to allow a platform to return the
- * interrupt number of its liking.
- */
- irq = get_c0_compare_int();
-
cd = &per_cpu(mips_clockevent_device, cpu);
cd->name = "MIPS";
@@ -320,7 +313,6 @@ int r4k_clockevent_init(void)
min_delta = calculate_min_delta();
cd->rating = 300;
- cd->irq = irq;
What should be the unset value is not clear, clock_event_device::irq
is an int, described in <linux/clockchips.h> as:
@irq: IRQ number (only for non CPU local devices)
Most arch clocks set irq > 0 or don't set it.
Core code / drivers check for irq != -1, irq != 0 or irq >= 0:
kernel/time/tick-common.c-295- if (newdev->irq >= 0 &&
!irq_can_set_affinity(newdev->irq))
kernel/time/tick-common.c-296- return false;
drivers/clocksource/exynos_mct.c-479- if (evt->irq == -1)
drivers/clocksource/exynos_mct.c-480- return -EIO;
drivers/clocksource/timer-ti-dm-systimer.c-562- if (!dev->irq)
drivers/clocksource/timer-ti-dm-systimer.c-563- return -ENXIO;
Using -1 for unset value seems reasonable, but since most don't set
this default value, I guess that's OK to do the same.
Reviewed-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
cd->cpumask = cpumask_of(cpu);
cd->set_next_event = mips_next_event;
cd->event_handler = mips_event_handler;
@@ -332,6 +324,13 @@ int r4k_clockevent_init(void)
cp0_timer_irq_installed = 1;
+ /*
+ * With vectored interrupts things are getting platform specific.
+ * get_c0_compare_int is a hook to allow a platform to return the
+ * interrupt number of its liking.
+ */
+ irq = get_c0_compare_int();
+
if (request_irq(irq, c0_compare_interrupt, flags, "timer",
c0_compare_interrupt))
pr_err("Failed to request irq %d (timer)\n", irq);
---
base-commit: 9e6869691724b12e1f43655eeedc35fade38120c
change-id: 20240812-get_c0_compare_int-66935853a308
Best regards,
