From 938179b4f8cf8a4f11234ebf2dff2eb48400acfe Mon Sep 17 00:00:00 2001
From: Dimitri Sivanich <sivanich@sgi.com>
Date: Fri, 5 Mar 2010 11:42:03 -0600
Subject: x86: Improve Intel microcode loader performance

We've noticed that on large SGI UV system configurations,
running microcode.ctl can take very long periods of time.  This
is due to the large number of vmalloc/vfree calls made by the
Intel generic_load_microcode() logic.

By reusing allocated space, the following patch reduces the time
to run microcode.ctl on a 1024 cpu system from approximately 80
seconds down to 1 or 2 seconds.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Acked-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Bill Davidsen <davidsen@tmr.com>
LKML-Reference: <20100305174203.GA19638@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 85a343e..3561702 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -343,10 +343,11 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
 				int (*get_ucode_data)(void *, const void *, size_t))
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-	u8 *ucode_ptr = data, *new_mc = NULL, *mc;
+	u8 *ucode_ptr = data, *new_mc = NULL, *mc = NULL;
 	int new_rev = uci->cpu_sig.rev;
 	unsigned int leftover = size;
 	enum ucode_state state = UCODE_OK;
+	unsigned int curr_mc_size = 0;
 
 	while (leftover) {
 		struct microcode_header_intel mc_header;
@@ -361,9 +362,15 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
 			break;
 		}
 
-		mc = vmalloc(mc_size);
-		if (!mc)
-			break;
+		/* For performance reasons, reuse mc area when possible */
+		if (!mc || mc_size > curr_mc_size) {
+			if (mc)
+				vfree(mc);
+			mc = vmalloc(mc_size);
+			if (!mc)
+				break;
+			curr_mc_size = mc_size;
+		}
 
 		if (get_ucode_data(mc, ucode_ptr, mc_size) ||
 		    microcode_sanity_check(mc) < 0) {
@@ -376,13 +383,16 @@ static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
 				vfree(new_mc);
 			new_rev = mc_header.rev;
 			new_mc  = mc;
-		} else
-			vfree(mc);
+			mc = NULL;	/* trigger new vmalloc */
+		}
 
 		ucode_ptr += mc_size;
 		leftover  -= mc_size;
 	}
 
+	if (mc)
+		vfree(mc);
+
 	if (leftover) {
 		if (new_mc)
 			vfree(new_mc);
-- 
cgit v0.10.2


From 3f10940e4fb69d312602078f2c5234206797ca31 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@relay.de.ibm.com>
Date: Sat, 10 Apr 2010 16:46:21 +0200
Subject: x86/microcode: Use nonseekable_open()

No need to seek on this file, so prevent it outright so we can
avoid using default_llseek - removes one more BKL usage.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[drop useless llseek = no_llseek and smp_lock.h inclusion]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnd Bergmann <arnd@relay.de.ibm.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Dmitry Adamushko <dmitry.adamushko@gmail.com>
LKML-Reference: <1270910781-8786-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index cceb5bc..2cd8c54 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -201,9 +201,9 @@ static int do_microcode_update(const void __user *buf, size_t size)
 	return error;
 }
 
-static int microcode_open(struct inode *unused1, struct file *unused2)
+static int microcode_open(struct inode *inode, struct file *file)
 {
-	return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
+	return capable(CAP_SYS_RAWIO) ? nonseekable_open(inode, file) : -EPERM;
 }
 
 static ssize_t microcode_write(struct file *file, const char __user *buf,
-- 
cgit v0.10.2