diff options
-rw-r--r-- | Documentation/powerpc/00-INDEX | 2 | ||||
-rw-r--r-- | Documentation/powerpc/ppc_htab.txt | 118 | ||||
-rw-r--r-- | include/linux/proc_fs.h | 1 |
3 files changed, 0 insertions, 121 deletions
diff --git a/Documentation/powerpc/00-INDEX b/Documentation/powerpc/00-INDEX index 29d839ce7327..2f31853899ca 100644 --- a/Documentation/powerpc/00-INDEX +++ b/Documentation/powerpc/00-INDEX | |||
@@ -18,8 +18,6 @@ mpc52xx.txt | |||
18 | - Linux 2.6.x on MPC52xx family | 18 | - Linux 2.6.x on MPC52xx family |
19 | mpc52xx-device-tree-bindings.txt | 19 | mpc52xx-device-tree-bindings.txt |
20 | - MPC5200 Device Tree Bindings | 20 | - MPC5200 Device Tree Bindings |
21 | ppc_htab.txt | ||
22 | - info about the Linux/PPC /proc/ppc_htab entry | ||
23 | smp.txt | 21 | smp.txt |
24 | - use and state info about Linux/PPC on MP machines | 22 | - use and state info about Linux/PPC on MP machines |
25 | sound.txt | 23 | sound.txt |
diff --git a/Documentation/powerpc/ppc_htab.txt b/Documentation/powerpc/ppc_htab.txt deleted file mode 100644 index 8b8c7df29fa9..000000000000 --- a/Documentation/powerpc/ppc_htab.txt +++ /dev/null | |||
@@ -1,118 +0,0 @@ | |||
1 | Information about /proc/ppc_htab | ||
2 | ===================================================================== | ||
3 | |||
4 | This document and the related code was written by me (Cort Dougan), please | ||
5 | email me (cort@fsmlabs.com) if you have questions, comments or corrections. | ||
6 | |||
7 | Last Change: 2.16.98 | ||
8 | |||
9 | This entry in the proc directory is readable by all users but only | ||
10 | writable by root. | ||
11 | |||
12 | The ppc_htab interface is a user level way of accessing the | ||
13 | performance monitoring registers as well as providing information | ||
14 | about the PTE hash table. | ||
15 | |||
16 | 1. Reading | ||
17 | |||
18 | Reading this file will give you information about the memory management | ||
19 | hash table that serves as an extended tlb for page translation on the | ||
20 | powerpc. It will also give you information about performance measurement | ||
21 | specific to the cpu that you are using. | ||
22 | |||
23 | Explanation of the 604 Performance Monitoring Fields: | ||
24 | MMCR0 - the current value of the MMCR0 register | ||
25 | PMC1 | ||
26 | PMC2 - the value of the performance counters and a | ||
27 | description of what events they are counting | ||
28 | which are based on MMCR0 bit settings. | ||
29 | Explanation of the PTE Hash Table fields: | ||
30 | |||
31 | Size - hash table size in Kb. | ||
32 | Buckets - number of buckets in the table. | ||
33 | Address - the virtual kernel address of the hash table base. | ||
34 | Entries - the number of ptes that can be stored in the hash table. | ||
35 | User/Kernel - how many pte's are in use by the kernel or user at that time. | ||
36 | Overflows - How many of the entries are in their secondary hash location. | ||
37 | Percent full - ratio of free pte entries to in use entries. | ||
38 | Reloads - Count of how many hash table misses have occurred | ||
39 | that were fixed with a reload from the linux tables. | ||
40 | Should always be 0 on 603 based machines. | ||
41 | Non-error Misses - Count of how many hash table misses have occurred | ||
42 | that were completed with the creation of a pte in the linux | ||
43 | tables with a call to do_page_fault(). | ||
44 | Error Misses - Number of misses due to errors such as bad address | ||
45 | and permission violations. This includes kernel access of | ||
46 | bad user addresses that are fixed up by the trap handler. | ||
47 | |||
48 | Note that calculation of the data displayed from /proc/ppc_htab takes | ||
49 | a long time and spends a great deal of time in the kernel. It would | ||
50 | be quite hard on performance to read this file constantly. In time | ||
51 | there may be a counter in the kernel that allows successive reads from | ||
52 | this file only after a given amount of time has passed to reduce the | ||
53 | possibility of a user slowing the system by reading this file. | ||
54 | |||
55 | 2. Writing | ||
56 | |||
57 | Writing to the ppc_htab allows you to change the characteristics of | ||
58 | the powerpc PTE hash table and setup performance monitoring. | ||
59 | |||
60 | Resizing the PTE hash table is not enabled right now due to many | ||
61 | complications with moving the hash table, rehashing the entries | ||
62 | and many many SMP issues that would have to be dealt with. | ||
63 | |||
64 | Write options to ppc_htab: | ||
65 | |||
66 | - To set the size of the hash table to 64Kb: | ||
67 | |||
68 | echo 'size 64' > /proc/ppc_htab | ||
69 | |||
70 | The size must be a multiple of 64 and must be greater than or equal to | ||
71 | 64. | ||
72 | |||
73 | - To turn off performance monitoring: | ||
74 | |||
75 | echo 'off' > /proc/ppc_htab | ||
76 | |||
77 | - To reset the counters without changing what they're counting: | ||
78 | |||
79 | echo 'reset' > /proc/ppc_htab | ||
80 | |||
81 | Note that counting will continue after the reset if it is enabled. | ||
82 | |||
83 | - To count only events in user mode or only in kernel mode: | ||
84 | |||
85 | echo 'user' > /proc/ppc_htab | ||
86 | ...or... | ||
87 | echo 'kernel' > /proc/ppc_htab | ||
88 | |||
89 | Note that these two options are exclusive of one another and the | ||
90 | lack of either of these options counts user and kernel. | ||
91 | Using 'reset' and 'off' reset these flags. | ||
92 | |||
93 | - The 604 has 2 performance counters which can each count events from | ||
94 | a specific set of events. These sets are disjoint so it is not | ||
95 | possible to count _any_ combination of 2 events. One event can | ||
96 | be counted by PMC1 and one by PMC2. | ||
97 | |||
98 | To start counting a particular event use: | ||
99 | |||
100 | echo 'event' > /proc/ppc_htab | ||
101 | |||
102 | and choose from these events: | ||
103 | |||
104 | PMC1 | ||
105 | ---- | ||
106 | 'ic miss' - instruction cache misses | ||
107 | 'dtlb' - data tlb misses (not hash table misses) | ||
108 | |||
109 | PMC2 | ||
110 | ---- | ||
111 | 'dc miss' - data cache misses | ||
112 | 'itlb' - instruction tlb misses (not hash table misses) | ||
113 | 'load miss time' - cycles to complete a load miss | ||
114 | |||
115 | 3. Bugs | ||
116 | |||
117 | The PMC1 and PMC2 counters can overflow and give no indication of that | ||
118 | in /proc/ppc_htab. | ||
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index fb61850d1cfc..27d534f4470d 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h | |||
@@ -139,7 +139,6 @@ extern int proc_readdir(struct file *, void *, filldir_t); | |||
139 | extern struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *); | 139 | extern struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *); |
140 | 140 | ||
141 | extern const struct file_operations proc_kcore_operations; | 141 | extern const struct file_operations proc_kcore_operations; |
142 | extern const struct file_operations ppc_htab_operations; | ||
143 | 142 | ||
144 | extern int pid_ns_prepare_proc(struct pid_namespace *ns); | 143 | extern int pid_ns_prepare_proc(struct pid_namespace *ns); |
145 | extern void pid_ns_release_proc(struct pid_namespace *ns); | 144 | extern void pid_ns_release_proc(struct pid_namespace *ns); |