x86/cacheinfo: Remove unneeded dead-store initialization
authorYang Li <yang.lee@linux.alibaba.com>
Wed, 31 Mar 2021 08:00:24 +0000 (16:00 +0800)
committerBorislav Petkov <bp@suse.de>
Wed, 7 Apr 2021 19:12:12 +0000 (21:12 +0200)
$ make CC=clang clang-analyzer

(needs clang-tidy installed on the system too)

on x86_64 defconfig triggers:

  arch/x86/kernel/cpu/cacheinfo.c:880:24: warning: Value stored to 'this_cpu_ci' \
  during its initialization is never read [clang-analyzer-deadcode.DeadStores]
        struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
                              ^
  arch/x86/kernel/cpu/cacheinfo.c:880:24: note: Value stored to 'this_cpu_ci' \
during its initialization is never read

So simply remove this unneeded dead-store initialization.

As compilers will detect this unneeded assignment and optimize this
anyway the resulting object code is identical before and after this
change.

No functional change. No change to object code.

 [ bp: Massage commit message. ]

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lkml.kernel.org/r/1617177624-24670-1-git-send-email-yang.lee@linux.alibaba.com
arch/x86/kernel/cpu/cacheinfo.c

index 3ca9be4..d66af29 100644 (file)
@@ -877,7 +877,7 @@ void init_intel_cacheinfo(struct cpuinfo_x86 *c)
 static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
                                    struct _cpuid4_info_regs *base)
 {
-       struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
+       struct cpu_cacheinfo *this_cpu_ci;
        struct cacheinfo *this_leaf;
        int i, sibling;