diff mbox series

[v3,1/3] cacheinfo: Use atomic allocation for percpu cache attributes

Message ID 20220720-arch_topo_fixes-v3-1-43d696288e84@arm.com (mailing list archive)
State New, archived
Headers show
Series arch_topology/cacheinfo: Fixes for v5.20 | expand

Commit Message

Sudeep Holla July 20, 2022, 12:55 p.m. UTC 
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>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
diff mbox series

Patch

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;