linux-kernel - Re: [PATCH 03/13] x86/microcode/AMD: Clean up find_equiv

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Message-ID: <20170117184927.fecw3m6cm6rb3p3j@pd.tnic>
Date:   Tue, 17 Jan 2017 19:49:27 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     X86 ML <x86@...nel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 03/13] x86/microcode/AMD: Clean up find_equiv_id()

On Tue, Jan 17, 2017 at 06:54:48PM +0100, Thomas Gleixner wrote:
> and even simpler:
> 
> 	for (; equiv_table->installed_cpu; equiv_table++)

Very nice, thanks!

Here's v1.1:

---
From: Borislav Petkov <bp@...e.de>
Date: Sun, 18 Dec 2016 12:05:50 +0100
Subject: [PATCH -v1.1 03/13] x86/microcode/AMD: Clean up find_equiv_id()

No need to have it marked "inline" - let gcc decide. Also, shorten the
argument name and simplify while-test.

While at it, make it into a proper for-loop and simplify it even more,
as tglx suggests.

No functionality change.

Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/kernel/cpu/microcode/amd.c | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 3f89e6712afe..142fb9950e2a 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -97,20 +97,12 @@ static size_t compute_container_size(u8 *data, u32 total_size)
 	return size;
 }
 
-static inline u16 find_equiv_id(struct equiv_cpu_entry *equiv_cpu_table,
-				unsigned int sig)
+static u16 find_equiv_id(struct equiv_cpu_entry *equiv_table, u32 sig)
 {
-	int i = 0;
-
-	if (!equiv_cpu_table)
-		return 0;
+	for (; equiv_table && equiv_table->installed_cpu; equiv_table++)
+		if (sig == equiv_table->installed_cpu)
+			return equiv_table->equiv_cpu;
 
-	while (equiv_cpu_table[i].installed_cpu != 0) {
-		if (sig == equiv_cpu_table[i].installed_cpu)
-			return equiv_cpu_table[i].equiv_cpu;
-
-		i++;
-	}
 	return 0;
 }
 
-- 
2.11.0

-- 
Regards/Gruss,
    Boris.

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