Re: [PATCH] drm/amdkfd: use time_is_before_jiffies(a + b) to replace "jiffies - a > b"

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



在 2022年07月28日 00:04, Felix Kuehling 写道:

This patch introduces a build warning for me:
   CC [M]  drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_interrupt.o
In file included from /home/fkuehlin/compute/kernel/include/linux/spinlock.h:54,
                  from /home/fkuehlin/compute/kernel/include/linux/mmzone.h:8,
                  from /home/fkuehlin/compute/kernel/include/linux/gfp.h:6,
                  from /home/fkuehlin/compute/kernel/include/linux/slab.h:15,
                  from /home/fkuehlin/compute/kernel/drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_interrupt.c:44:
/home/fkuehlin/compute/kernel/drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_interrupt.c: In function ?interrupt_wq?:
/home/fkuehlin/compute/kernel/include/linux/typecheck.h:12:18: warning: comparison of distinct pointer types lacks a cast
    12 |  (void)(&__dummy == &__dummy2); \
       |                  ^~
/home/fkuehlin/compute/kernel/include/linux/jiffies.h:106:3: note: in expansion of macro ?typecheck?
   106 |   typecheck(unsigned long, b) && \
       |   ^~~~~~~~~
/home/fkuehlin/compute/kernel/include/linux/jiffies.h:154:35: note: in expansion of macro ?time_after?
   154 | #define time_is_before_jiffies(a) time_after(jiffies, a)
       |                                   ^~~~~~~~~~
/home/fkuehlin/compute/kernel/drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_interrupt.c:159:7: note: in expansion of macro ?time_is_before_jiffies?
   159 |   if (time_is_before_jiffies(start_jiffies + HZ)) {
       |       ^~~~~~~~~~~~~~~~~~~~~~
I think you need to change the the definition of start_jiffies to be
unsigned long. Do you want to submit a v2 of your patch?

Yes, I will submit v2 patch later.

That said, I think the existing code was fine, though the type-mismatch
highlighted by your patch is a bit iffy.

And if the timer wrap changes in the future you won't have to alter your driver code. So I think it's better.

Regards,
   Felix
Am 2022-07-26 um 22:59 schrieb Yu Zhe:
time_is_before_jiffies deals with timer wrapping correctly.
Signed-off-by: Yu Zhe <yuzhe@xxxxxxxxxxxx>
---
   drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c | 2 +-
   1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
index a9466d154395..6397926e059c 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
@@ -156,7 +156,7 @@ static void interrupt_wq(struct work_struct *work)
       while (dequeue_ih_ring_entry(dev, ih_ring_entry)) {
           dev->device_info.event_interrupt_class->interrupt_wq(dev,
                                   ih_ring_entry);
-        if (jiffies - start_jiffies > HZ) {
+        if (time_is_before_jiffies(start_jiffies + HZ)) {
               /* If we spent more than a second processing signals,
                * reschedule the worker to avoid soft-lockup warnings
                */




[Index of Archives]     [Kernel Development]     [Kernel Announce]     [Kernel Newbies]     [Linux Networking Development]     [Share Photos]     [IDE]     [Security]     [Git]     [Netfilter]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Device Mapper]

  Powered by Linux