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generic-ipi: Use DEFINE_PER_CPU_SHARED_ALIGNED for IPI data

PATCH In review Anton Blanchard 3 participants 3 messages Jan 18, 2010 – Jan 19, 2010

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PATCH 1/1 generic-ipi: Use DEFINE_PER_CPU_SHARED_ALIGNED for IPI data

From: Milton Miller <[email protected]>

The smp ipi data is passed around and given write access by other cpus and should be seperated from per-cpu data consumed by this cpu.

Looking for hot lines, I saw call_function_data shared with tick_cpu_sched.

---

kernel/smp.c +4 -4
Index: linux.trees.git/kernel/smp.c
===================================================================
@@ -12,8 +12,6 @@
 #include <linux/smp.h>
 #include <linux/cpu.h>
 
-static DEFINE_PER_CPU(struct call_single_queue, call_single_queue);
-
 static struct {
 	struct list_head	queue;
 	raw_spinlock_t		lock;
@@ -33,12 +31,14 @@ struct call_function_data {
 	cpumask_var_t		cpumask;
 };
 
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_function_data, cfd_data);
+
 struct call_single_queue {
 	struct list_head	list;
 	raw_spinlock_t		lock;
 };
 
-static DEFINE_PER_CPU(struct call_function_data, cfd_data);
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_queue, call_single_queue);
 
 static int
 hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
@@ -256,7 +256,7 @@ void generic_smp_call_function_single_in
 	}
 }
 
-static DEFINE_PER_CPU(struct call_single_data, csd_data);
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
 
 /*
  * smp_call_function_single - Run a function on a specific CPU
Acked-by on v1 1/1
#1 lore raw
Quoted 6 lines · Anton Blanchard

From: Milton Miller <[email protected]>

The smp ipi data is passed around and given write access by other cpus and should be seperated from per-cpu data consumed by this cpu.

Looking for hot lines, I saw call_function_data shared with tick_cpu_sched.

Looks good to me.

Signature · 1 line
Jens Axboe
#2 lore raw

[tip:core/ipi] generic-ipi: Optimize accesses by using DEFINE_PER_CPU_SHARED_ALIGNED for IPI data

In reply to Anton Blanchard
Commit-ID:  e03bcb68629c7f0728c95f1afe06ce48565c7713
Gitweb:     http://git.kernel.org/tip/e03bcb68629c7f0728c95f1afe06ce48565c7713
Author:     Milton Miller <[email protected]>
AuthorDate: Mon, 18 Jan 2010 13:00:51 +1100
Committer:  Ingo Molnar <[email protected]>
CommitDate: Mon, 18 Jan 2010 09:02:59 +0100

generic-ipi: Optimize accesses by using DEFINE_PER_CPU_SHARED_ALIGNED for IPI data

The smp ipi data is passed around and given write access by other cpus and should be separated from per-cpu data consumed by this cpu.

Looking for hot lines, I saw call_function_data shared with tick_cpu_sched.

LKML-Reference: <20100118020051.GR12666@kryten>

---
 kernel/smp.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
kernel/smp.c +4 -4
index f104084..9867b6b 100644
@@ -12,8 +12,6 @@
 #include <linux/smp.h>
 #include <linux/cpu.h>
 
-static DEFINE_PER_CPU(struct call_single_queue, call_single_queue);
-
 static struct {
 	struct list_head	queue;
 	raw_spinlock_t		lock;
@@ -33,12 +31,14 @@ struct call_function_data {
 	cpumask_var_t		cpumask;
 };
 
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_function_data, cfd_data);
+
 struct call_single_queue {
 	struct list_head	list;
 	raw_spinlock_t		lock;
 };
 
-static DEFINE_PER_CPU(struct call_function_data, cfd_data);
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_queue, call_single_queue);
 
 static int
 hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
@@ -256,7 +256,7 @@ void generic_smp_call_function_single_interrupt(void)
 	}
 }
 
-static DEFINE_PER_CPU(struct call_single_data, csd_data);
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_single_data, csd_data);
 
 /*
  * smp_call_function_single - Run a function on a specific CPU