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 b9ba19dbdb6943a187d3873b84228eb76060d254..6ff552e48007bdf22d74c563735a233747c38069 100644 (file)
--- 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);