linux-kernel - [tip:x86/boot] x86: Convert a few more per-CPU items to read-mostly ones

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Tue, 4 Nov 2014 11:15:54 -0800
From:	tip-bot for Jan Beulich <tipbot@...or.com>
To:	linux-tip-commits@...r.kernel.org
Cc:	mingo@...nel.org, JBeulich@...e.com, jbeulich@...e.com,
	hpa@...or.com, tglx@...utronix.de, linux-kernel@...r.kernel.org
Subject: [tip:x86/boot] x86:
  Convert a few more per-CPU items to read-mostly ones

Commit-ID:  2c773dd31fbacbbb6425f8a9d3f97e0010272368
Gitweb:     http://git.kernel.org/tip/2c773dd31fbacbbb6425f8a9d3f97e0010272368
Author:     Jan Beulich <JBeulich@...e.com>
AuthorDate: Tue, 4 Nov 2014 08:26:42 +0000
Committer:  Thomas Gleixner <tglx@...utronix.de>
CommitDate: Tue, 4 Nov 2014 20:13:28 +0100

x86: Convert a few more per-CPU items to read-mostly ones

Both this_cpu_off and cpu_info aren't getting modified post boot, yet
are being accessed on enough code paths that grouping them with other
frequently read items seems desirable. For cpu_info this at the same
time implies removing the cache line alignment (which afaict became
pointless when it got converted to per-CPU data years ago).

Signed-off-by: Jan Beulich <jbeulich@...e.com>
Link: http://lkml.kernel.org/r/54589BD20200007800044A84@mail.emea.novell.com
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
---
 arch/x86/include/asm/percpu.h    | 2 +-
 arch/x86/include/asm/processor.h | 4 ++--
 arch/x86/kernel/setup_percpu.c   | 2 +-
 arch/x86/kernel/smpboot.c        | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/percpu.h b/arch/x86/include/asm/percpu.h
index fd47218..74da317 100644
--- a/arch/x86/include/asm/percpu.h
+++ b/arch/x86/include/asm/percpu.h
@@ -522,7 +522,7 @@ static inline int x86_this_cpu_variable_test_bit(int nr,
 #include <asm-generic/percpu.h>
 
 /* We can use this directly for local CPU (faster). */
-DECLARE_PER_CPU(unsigned long, this_cpu_off);
+DECLARE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off);
 
 #endif /* !__ASSEMBLY__ */
 
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index eb71ec7..3aeb31c 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -127,7 +127,7 @@ struct cpuinfo_x86 {
 	/* Index into per_cpu list: */
 	u16			cpu_index;
 	u32			microcode;
-} __attribute__((__aligned__(SMP_CACHE_BYTES)));
+};
 
 #define X86_VENDOR_INTEL	0
 #define X86_VENDOR_CYRIX	1
@@ -151,7 +151,7 @@ extern __u32			cpu_caps_cleared[NCAPINTS];
 extern __u32			cpu_caps_set[NCAPINTS];
 
 #ifdef CONFIG_SMP
-DECLARE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
+DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
 #define cpu_data(cpu)		per_cpu(cpu_info, cpu)
 #else
 #define cpu_info		boot_cpu_data
diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index 5cdff03..e4fcb87 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -30,7 +30,7 @@ EXPORT_PER_CPU_SYMBOL(cpu_number);
 #define BOOT_PERCPU_OFFSET 0
 #endif
 
-DEFINE_PER_CPU(unsigned long, this_cpu_off) = BOOT_PERCPU_OFFSET;
+DEFINE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off) = BOOT_PERCPU_OFFSET;
 EXPORT_PER_CPU_SYMBOL(this_cpu_off);
 
 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = {
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 4d2128a..a03ec604 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -99,7 +99,7 @@ EXPORT_PER_CPU_SYMBOL(cpu_core_map);
 DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map);
 
 /* Per CPU bogomips and other parameters */
-DEFINE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
+DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
 EXPORT_PER_CPU_SYMBOL(cpu_info);
 
 atomic_t init_deasserted;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/