From: Marcelo Tosatti <mtosatti@redhat.com>
Date: Mon, 20 Mar 2023 18:03:34 +0000 (-0300)
Subject: this_cpu_cmpxchg: ARM64: switch this_cpu_cmpxchg to locked, add _local function
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=b605a5a8782f7ec0e2e5f5b17e238ed5c38c615a;p=users%2Fjedix%2Flinux-maple.git

this_cpu_cmpxchg: ARM64: switch this_cpu_cmpxchg to locked, add _local function

Goal is to have vmstat_shepherd to transfer from per-CPU counters to
global counters remotely.  For this, an atomic this_cpu_cmpxchg is
necessary.

Following the kernel convention for cmpxchg/cmpxchg_local, change ARM's
this_cpu_cmpxchg_ helpers to be atomic, and add this_cpu_cmpxchg_local_
helpers which are not atomic.

Link: https://lkml.kernel.org/r/20230320180745.582248645@redhat.com
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Aaron Tomlin <atomlin@atomlin.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h
index b9ba19dbdb694..6ff552e48007b 100644
--- a/arch/arm64/include/asm/percpu.h
+++ b/arch/arm64/include/asm/percpu.h
@@ -232,13 +232,23 @@ PERCPU_RET_OP(add, add, ldadd)
 	_pcp_protect_return(xchg_relaxed, pcp, val)
 
 #define this_cpu_cmpxchg_1(pcp, o, n)	\
-	_pcp_protect_return(cmpxchg_relaxed, pcp, o, n)
+	_pcp_protect_return(cmpxchg, pcp, o, n)
 #define this_cpu_cmpxchg_2(pcp, o, n)	\
-	_pcp_protect_return(cmpxchg_relaxed, pcp, o, n)
+	_pcp_protect_return(cmpxchg, pcp, o, n)
 #define this_cpu_cmpxchg_4(pcp, o, n)	\
-	_pcp_protect_return(cmpxchg_relaxed, pcp, o, n)
+	_pcp_protect_return(cmpxchg, pcp, o, n)
 #define this_cpu_cmpxchg_8(pcp, o, n)	\
+	_pcp_protect_return(cmpxchg, pcp, o, n)
+
+#define this_cpu_cmpxchg_local_1(pcp, o, n)	\
 	_pcp_protect_return(cmpxchg_relaxed, pcp, o, n)
+#define this_cpu_cmpxchg_local_2(pcp, o, n)	\
+	_pcp_protect_return(cmpxchg_relaxed, pcp, o, n)
+#define this_cpu_cmpxchg_local_4(pcp, o, n)	\
+	_pcp_protect_return(cmpxchg_relaxed, pcp, o, n)
+#define this_cpu_cmpxchg_local_8(pcp, o, n)	\
+	_pcp_protect_return(cmpxchg_relaxed, pcp, o, n)
+
 
 #ifdef __KVM_NVHE_HYPERVISOR__
 extern unsigned long __hyp_per_cpu_offset(unsigned int cpu);