diff options
author | Steven Rostedt <rostedt@goodmis.org> | 2008-11-12 17:52:36 -0500 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-11-13 03:49:21 -0500 |
commit | a94c80e78bc9f4493ffc25a02d5d7bcd93c399d0 (patch) | |
tree | 7bccb9ade6edc033887db7c6f9f7157c5d612e3c /Documentation/ftrace.txt | |
parent | 24de38620dd3504782c90c0892eef888d0c351e9 (diff) |
ftrace: rename trace_entries to buffer_size_kb
Impact: rename of debugfs file trace_entries to buffer_size_kb
The original ftrace had fixed size entries, and the number of entries
was shown and modified via the file called trace_entries. By converting
to the unified trace buffer, we now allow for variable size entries
which makes the meaning of trace_entries pointless.
Since trace_size might be confused to the size of the trace, this patch
names it "buffer_size_kb" (thanks to Arjan van de Ven for this idea).
[ mingo@elte.hu: changed from buffer_size to buffer_size_kb ]
( Note, the units are still bytes - the next patch changes that,
to keep the wide rename patch separate from the unit-change patch. )
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'Documentation/ftrace.txt')
-rw-r--r-- | Documentation/ftrace.txt | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/Documentation/ftrace.txt b/Documentation/ftrace.txt index 9cc4d685dde5..a1b58777839b 100644 --- a/Documentation/ftrace.txt +++ b/Documentation/ftrace.txt | |||
@@ -94,7 +94,7 @@ of ftrace. Here is a list of some of the key files: | |||
94 | only be recorded if the latency is greater than | 94 | only be recorded if the latency is greater than |
95 | the value in this file. (in microseconds) | 95 | the value in this file. (in microseconds) |
96 | 96 | ||
97 | trace_entries: This sets or displays the number of bytes each CPU | 97 | buffer_size_kb: This sets or displays the number of bytes each CPU |
98 | buffer can hold. The tracer buffers are the same size | 98 | buffer can hold. The tracer buffers are the same size |
99 | for each CPU. The displayed number is the size of the | 99 | for each CPU. The displayed number is the size of the |
100 | CPU buffer and not total size of all buffers. The | 100 | CPU buffer and not total size of all buffers. The |
@@ -1299,13 +1299,13 @@ trace entries | |||
1299 | ------------- | 1299 | ------------- |
1300 | 1300 | ||
1301 | Having too much or not enough data can be troublesome in diagnosing | 1301 | Having too much or not enough data can be troublesome in diagnosing |
1302 | an issue in the kernel. The file trace_entries is used to modify | 1302 | an issue in the kernel. The file buffer_size_kb is used to modify |
1303 | the size of the internal trace buffers. The number listed | 1303 | the size of the internal trace buffers. The number listed |
1304 | is the number of entries that can be recorded per CPU. To know | 1304 | is the number of entries that can be recorded per CPU. To know |
1305 | the full size, multiply the number of possible CPUS with the | 1305 | the full size, multiply the number of possible CPUS with the |
1306 | number of entries. | 1306 | number of entries. |
1307 | 1307 | ||
1308 | # cat /debug/tracing/trace_entries | 1308 | # cat /debug/tracing/buffer_size_kb |
1309 | 65620 | 1309 | 65620 |
1310 | 1310 | ||
1311 | Note, to modify this, you must have tracing completely disabled. To do that, | 1311 | Note, to modify this, you must have tracing completely disabled. To do that, |
@@ -1313,8 +1313,8 @@ echo "nop" into the current_tracer. If the current_tracer is not set | |||
1313 | to "nop", an EINVAL error will be returned. | 1313 | to "nop", an EINVAL error will be returned. |
1314 | 1314 | ||
1315 | # echo nop > /debug/tracing/current_tracer | 1315 | # echo nop > /debug/tracing/current_tracer |
1316 | # echo 100000 > /debug/tracing/trace_entries | 1316 | # echo 100000 > /debug/tracing/buffer_size_kb |
1317 | # cat /debug/tracing/trace_entries | 1317 | # cat /debug/tracing/buffer_size_kb |
1318 | 100045 | 1318 | 100045 |
1319 | 1319 | ||
1320 | 1320 | ||
@@ -1323,8 +1323,8 @@ are held in individual pages. It allocates the number of pages it takes | |||
1323 | to fulfill the request. If more entries may fit on the last page | 1323 | to fulfill the request. If more entries may fit on the last page |
1324 | then they will be added. | 1324 | then they will be added. |
1325 | 1325 | ||
1326 | # echo 1 > /debug/tracing/trace_entries | 1326 | # echo 1 > /debug/tracing/buffer_size_kb |
1327 | # cat /debug/tracing/trace_entries | 1327 | # cat /debug/tracing/buffer_size_kb |
1328 | 85 | 1328 | 85 |
1329 | 1329 | ||
1330 | This shows us that 85 entries can fit in a single page. | 1330 | This shows us that 85 entries can fit in a single page. |
@@ -1332,8 +1332,8 @@ This shows us that 85 entries can fit in a single page. | |||
1332 | The number of pages which will be allocated is limited to a percentage | 1332 | The number of pages which will be allocated is limited to a percentage |
1333 | of available memory. Allocating too much will produce an error. | 1333 | of available memory. Allocating too much will produce an error. |
1334 | 1334 | ||
1335 | # echo 1000000000000 > /debug/tracing/trace_entries | 1335 | # echo 1000000000000 > /debug/tracing/buffer_size_kb |
1336 | -bash: echo: write error: Cannot allocate memory | 1336 | -bash: echo: write error: Cannot allocate memory |
1337 | # cat /debug/tracing/trace_entries | 1337 | # cat /debug/tracing/buffer_size_kb |
1338 | 85 | 1338 | 85 |
1339 | 1339 | ||