This is a note to let you know that I've just added the patch titled
powerpc/topology: Check if a core is online
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-topology-check-if-a-core-is-online.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 1f8e97f12700f9f4dfaa3b2d1aad7b39609c1890
Author: Nysal Jan K.A <nysal@xxxxxxxxxxxxx>
Date: Wed Jul 31 08:31:13 2024 +0530
powerpc/topology: Check if a core is online
[ Upstream commit 227bbaabe64b6f9cd98aa051454c1d4a194a8c6a ]
topology_is_core_online() checks if the core a CPU belongs to
is online. The core is online if at least one of the sibling
CPUs is online. The first CPU of an online core is also online
in the common case, so this should be fairly quick.
Fixes: 73c58e7e1412 ("powerpc: Add HOTPLUG_SMT support")
Signed-off-by: Nysal Jan K.A <nysal@xxxxxxxxxxxxx>
Reviewed-by: Shrikanth Hegde <sshegde@xxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://msgid.link/20240731030126.956210-3-nysal@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h
index f4e6f2dd04b73..16bacfe8c7a2c 100644
--- a/arch/powerpc/include/asm/topology.h
+++ b/arch/powerpc/include/asm/topology.h
@@ -145,6 +145,7 @@ static inline int cpu_to_coregroup_id(int cpu)
#ifdef CONFIG_HOTPLUG_SMT
#include <linux/cpu_smt.h>
+#include <linux/cpumask.h>
#include <asm/cputhreads.h>
static inline bool topology_is_primary_thread(unsigned int cpu)
@@ -156,6 +157,18 @@ static inline bool topology_smt_thread_allowed(unsigned int cpu)
{
return cpu_thread_in_core(cpu) < cpu_smt_num_threads;
}
+
+#define topology_is_core_online topology_is_core_online
+static inline bool topology_is_core_online(unsigned int cpu)
+{
+ int i, first_cpu = cpu_first_thread_sibling(cpu);
+
+ for (i = first_cpu; i < first_cpu + threads_per_core; ++i) {
+ if (cpu_online(i))
+ return true;
+ }
+ return false;
+}
#endif
#endif /* __KERNEL__ */
