[Xen-devel] [PATCH] xen: x86: make init_intel_cacheinfo() void.

Dario Faggioli posted 1 patch 4 years ago
Patches applied successfully (tree, apply log)
git fetch https://github.com/patchew-project/xen tags/patchew/158524305235.31663.14043511848631384508.stgit@Palanthas
xen/arch/x86/cpu/intel.c           |    4 +---
xen/arch/x86/cpu/intel_cacheinfo.c |    4 +---
xen/include/asm-x86/processor.h    |    2 +-
3 files changed, 3 insertions(+), 7 deletions(-)
[Xen-devel] [PATCH] xen: x86: make init_intel_cacheinfo() void.
Posted by Dario Faggioli 4 years ago
It seems that we took this code from Linux, back when the function was
'unsigned int' and the return value was used.

But we are currently not doing anything with such value, so let's get
rid of it and make the function void. As an anecdote, that's pretty much
the same that happened in Linux as, since commit 807e9bc8e2fe6 ("x86/CPU:
Move cpu_detect_cache_sizes() into init_intel_cacheinfo()") the function
is void there too.

Signed-off-by: Dario Faggioli <dfaggioli@suse.com>
---
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Wei Liu <wl@xen.org>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
---
 xen/arch/x86/cpu/intel.c           |    4 +---
 xen/arch/x86/cpu/intel_cacheinfo.c |    4 +---
 xen/include/asm-x86/processor.h    |    2 +-
 3 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/xen/arch/x86/cpu/intel.c b/xen/arch/x86/cpu/intel.c
index 4d7324e4d0..7966f4aa8a 100644
--- a/xen/arch/x86/cpu/intel.c
+++ b/xen/arch/x86/cpu/intel.c
@@ -346,12 +346,10 @@ static int num_cpu_cores(struct cpuinfo_x86 *c)
 
 static void init_intel(struct cpuinfo_x86 *c)
 {
-	unsigned int l2 = 0;
-
 	/* Detect the extended topology information if available */
 	detect_extended_topology(c);
 
-	l2 = init_intel_cacheinfo(c);
+	init_intel_cacheinfo(c);
 	if (c->cpuid_level > 9) {
 		unsigned eax = cpuid_eax(10);
 		/* Check for version and the number of counters */
diff --git a/xen/arch/x86/cpu/intel_cacheinfo.c b/xen/arch/x86/cpu/intel_cacheinfo.c
index 88b61fddfe..5624e8056d 100644
--- a/xen/arch/x86/cpu/intel_cacheinfo.c
+++ b/xen/arch/x86/cpu/intel_cacheinfo.c
@@ -116,7 +116,7 @@ static int find_num_cache_leaves(void)
 	return i;
 }
 
-unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c)
+void init_intel_cacheinfo(struct cpuinfo_x86 *c)
 {
 	unsigned int trace = 0, l1i = 0, l1d = 0, l2 = 0, l3 = 0; /* Cache sizes */
 	unsigned int new_l1d = 0, new_l1i = 0; /* Cache sizes from cpuid(4) */
@@ -262,6 +262,4 @@ unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c)
 	}
 
 	c->x86_cache_size = l3 ? l3 : (l2 ? l2 : (l1i+l1d));
-
-	return l2;
 }
diff --git a/xen/include/asm-x86/processor.h b/xen/include/asm-x86/processor.h
index fe231c5072..ea6e5497f4 100644
--- a/xen/include/asm-x86/processor.h
+++ b/xen/include/asm-x86/processor.h
@@ -166,7 +166,7 @@ extern void identify_cpu(struct cpuinfo_x86 *);
 extern void setup_clear_cpu_cap(unsigned int);
 extern void setup_force_cpu_cap(unsigned int);
 extern void print_cpu_info(unsigned int cpu);
-extern unsigned int init_intel_cacheinfo(struct cpuinfo_x86 *c);
+extern void init_intel_cacheinfo(struct cpuinfo_x86 *c);
 
 #define cpu_to_core(_cpu)   (cpu_data[_cpu].cpu_core_id)
 #define cpu_to_socket(_cpu) (cpu_data[_cpu].phys_proc_id)


Re: [Xen-devel] [PATCH] xen: x86: make init_intel_cacheinfo() void.
Posted by Andrew Cooper 4 years ago
On 26/03/2020 17:17, Dario Faggioli wrote:
> It seems that we took this code from Linux, back when the function was
> 'unsigned int' and the return value was used.
>
> But we are currently not doing anything with such value, so let's get
> rid of it and make the function void. As an anecdote, that's pretty much
> the same that happened in Linux as, since commit 807e9bc8e2fe6 ("x86/CPU:
> Move cpu_detect_cache_sizes() into init_intel_cacheinfo()") the function
> is void there too.
>
> Signed-off-by: Dario Faggioli <dfaggioli@suse.com>

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

Furthermore, Shanghai already uses this in its form.