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authorPaul Mundt <lethal@linux-sh.org>2008-12-10 10:06:36 +0100
committerPaul Mundt <lethal@linux-sh.org>2008-12-22 10:44:03 +0100
commita99d6fde69dd9c73ac0b4e42a77ed1ebc714e56a (patch)
tree96d0136b37139a696265b7218e7037ce09a19873 /arch/sh/mm
parentsh: Kill off sh64's unused alloc/free_task_struct() definitions. (diff)
downloadlinux-a99d6fde69dd9c73ac0b4e42a77ed1ebc714e56a.tar.xz
linux-a99d6fde69dd9c73ac0b4e42a77ed1ebc714e56a.zip
sh: Convert sh64 /proc/asids to debugfs and generic sh.
This converts the sh64 /proc/asids entry to debugfs and enables it for all SH parts that have debugfs enabled. On MMU systems this can be used to determine which processes are using which ASIDs which in turn can be used for finer grained cache tag analysis. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'arch/sh/mm')
-rw-r--r--arch/sh/mm/Makefile_321
-rw-r--r--arch/sh/mm/Makefile_641
-rw-r--r--arch/sh/mm/asids-debugfs.c79
3 files changed, 81 insertions, 0 deletions
diff --git a/arch/sh/mm/Makefile_32 b/arch/sh/mm/Makefile_32
index f066e76da204..cb2f3f299591 100644
--- a/arch/sh/mm/Makefile_32
+++ b/arch/sh/mm/Makefile_32
@@ -18,6 +18,7 @@ mmu-y := tlb-nommu.o pg-nommu.o
mmu-$(CONFIG_MMU) := fault_32.o tlbflush_32.o ioremap_32.o
obj-y += $(mmu-y)
+obj-$(CONFIG_DEBUG_FS) += asids-debugfs.o
ifdef CONFIG_DEBUG_FS
obj-$(CONFIG_CPU_SH4) += cache-debugfs.o
diff --git a/arch/sh/mm/Makefile_64 b/arch/sh/mm/Makefile_64
index 9481d0f54efd..2863ffb7006d 100644
--- a/arch/sh/mm/Makefile_64
+++ b/arch/sh/mm/Makefile_64
@@ -13,6 +13,7 @@ obj-y += cache-sh5.o
endif
obj-y += $(mmu-y)
+obj-$(CONFIG_DEBUG_FS) += asids-debugfs.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
obj-$(CONFIG_NUMA) += numa.o
diff --git a/arch/sh/mm/asids-debugfs.c b/arch/sh/mm/asids-debugfs.c
new file mode 100644
index 000000000000..0678a1044a9a
--- /dev/null
+++ b/arch/sh/mm/asids-debugfs.c
@@ -0,0 +1,79 @@
+/*
+ * debugfs ops for process ASIDs
+ *
+ * Copyright (C) 2000, 2001 Paolo Alberelli
+ * Copyright (C) 2003 - 2008 Paul Mundt
+ * Copyright (C) 2003, 2004 Richard Curnow
+ *
+ * Provides a debugfs file that lists out the ASIDs currently associated
+ * with the processes.
+ *
+ * In the SH-5 case, if the DM.PC register is examined through the debug
+ * link, this shows ASID + PC. To make use of this, the PID->ASID
+ * relationship needs to be known. This is primarily for debugging.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/spinlock.h>
+#include <asm/processor.h>
+#include <asm/mmu_context.h>
+
+static int asids_seq_show(struct seq_file *file, void *iter)
+{
+ struct task_struct *p;
+
+ read_lock(&tasklist_lock);
+
+ for_each_process(p) {
+ int pid = p->pid;
+
+ if (unlikely(!pid))
+ continue;
+
+ if (p->mm)
+ seq_printf(file, "%5d : %02x\n", pid,
+ cpu_asid(smp_processor_id(), p->mm));
+ else
+ seq_printf(file, "%5d : (none)\n", pid);
+ }
+
+ read_unlock(&tasklist_lock);
+
+ return 0;
+}
+
+static int asids_debugfs_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, asids_seq_show, inode->i_private);
+}
+
+static const struct file_operations asids_debugfs_fops = {
+ .owner = THIS_MODULE,
+ .open = asids_debugfs_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init asids_debugfs_init(void)
+{
+ struct dentry *asids_dentry;
+
+ asids_dentry = debugfs_create_file("asids", S_IRUSR, sh_debugfs_root,
+ NULL, &asids_debugfs_fops);
+ if (!asids_dentry)
+ return -ENOMEM;
+ if (IS_ERR(asids_dentry))
+ return PTR_ERR(asids_dentry);
+
+ return 0;
+}
+module_init(asids_debugfs_init);
+
+MODULE_LICENSE("GPL v2");