lkml.org 
[lkml]   [2022]   [Jul]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
SubjectRe: [PATCH -next v2 1/2] cacheinfo: Use atomic allocation for percpu cache attributes
Date
On 15/07/2022 11:26, Sudeep Holla wrote:
> On couple of architectures like RISC-V and ARM64, we need to detect
> cache attribues quite early during the boot when the secondary CPUs
> start. So we will call detect_cache_attributes in the atomic context
> and since use of normal allocation can sleep, we will end up getting
> "sleeping in the atomic context" bug splat.
>
> In order avoid that, move the allocation to use atomic version in
> preparation to move the actual detection of cache attributes in the
> CPU hotplug path which is atomic.
>
> Cc: Ionela Voinescu <ionela.voinescu@arm.com>
> Tested-by: Conor Dooley <conor.dooley@microchip.com>

Since this was a conversion from comments on the other series:
Acked-by: Conor Dooley <conor.dooley@microchip.com>

> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> ---
> drivers/base/cacheinfo.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> Hi Greg,
>
> Can you apply these couple of patches directly if and when you are happy
> with them ?
>
> Regards,
> Sudeep
>
> v1->v2: This was added in v2
>
> diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
> index 65d566ff24c4..4b5cd08c5a65 100644
> --- a/drivers/base/cacheinfo.c
> +++ b/drivers/base/cacheinfo.c
> @@ -356,7 +356,7 @@ int detect_cache_attributes(unsigned int cpu)
> return -ENOENT;
>
> per_cpu_cacheinfo(cpu) = kcalloc(cache_leaves(cpu),
> - sizeof(struct cacheinfo), GFP_KERNEL);
> + sizeof(struct cacheinfo), GFP_ATOMIC);
> if (per_cpu_cacheinfo(cpu) == NULL) {
> cache_leaves(cpu) = 0;
> return -ENOMEM;
> --
> 2.37.1
>
\
 
 \ /
  Last update: 2022-07-15 12:34    [W:0.294 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site