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authorRalf Baechle <ralf@linux-mips.org>1997-09-12 01:29:55 +0000
committerRalf Baechle <ralf@linux-mips.org>1997-09-12 01:29:55 +0000
commit545f435ebcfd94a1e7c20b46efe81b4d6ac4e698 (patch)
treee9ce4bc598d06374bda906f18365984bf22a526a /Documentation/powerpc
parent4291a610eef89d0d5c69d9a10ee6560e1aa36c74 (diff)
Merge with Linux 2.1.55. More bugfixes and goodies from my private
CVS archive.
Diffstat (limited to 'Documentation/powerpc')
-rw-r--r--Documentation/powerpc/00-INDEX9
-rw-r--r--Documentation/powerpc/ppc_htab.txt50
2 files changed, 59 insertions, 0 deletions
diff --git a/Documentation/powerpc/00-INDEX b/Documentation/powerpc/00-INDEX
new file mode 100644
index 000000000..48e8fa2d5
--- /dev/null
+++ b/Documentation/powerpc/00-INDEX
@@ -0,0 +1,9 @@
+Index of files in Documentation/powerpc. If you think something about
+Linux/PPC needs an entry here, needs correction of you've written one
+please mail me.
+ Cort Dougan (cort@cs.nmt.edu)
+
+00-INDEX
+ - this file
+ppc_htab.txt
+ - info about the Linux/PPC /proc/ppc_htab entry
diff --git a/Documentation/powerpc/ppc_htab.txt b/Documentation/powerpc/ppc_htab.txt
new file mode 100644
index 000000000..e114726f1
--- /dev/null
+++ b/Documentation/powerpc/ppc_htab.txt
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+ Information about /proc/ppc_htab
+=====================================================================
+
+This entry in the proc directory is readable by all users but only
+writable by root.
+
+
+1. Reading
+
+ Reading this file will give you information about the memory management
+ hash table that serves as an extended tlb for page translation on the
+ powerpc.
+
+ Explaination of the fields:
+
+ Size - hash table size in Kb.
+ Buckets - number of buckets in the table.
+ Addess - the virtual kernel address of the hash table base.
+ Entries - the number of ptes that can be stored in the hash table.
+ User/Kernel - how many pte's are in use by the kernel or user at that time.
+ Overflows - How many of the entries are in their secondary hash location.
+ Percent full - ratio of free pte entries to in use entries.
+
+ Note that calculation of the data displayed from /proc/ppc_htab takes
+ a long time and spends a great deal of time in the kernel. It would
+ be quite hard on performance to read this file constantly. In time
+ there may be a counter in the kernel that allows successive reads from
+ this file only after a given amount of time has passed to reduce the
+ possibility of a user slowing the system by reading this file.
+
+2. Writing
+
+ Writing to ppc_htab is not yet allowed.
+
+ Write options to ppc_htab:
+
+ - To set the size of the hash table to 64Kb:
+
+ echo 'size 64' > /dev/ppc_htab
+
+ The size must be a multiple of 64 and must be greater than or equal to
+ 64.
+
+
+
+
+
+
+
+