Messages in this thread | | | Date | Thu, 13 Nov 2008 00:14:11 +0100 | From | "Frédéric Weisbecker" <> | Subject | Re: [PATCH 1/3] ftrace: rename trace_entries to buffer_size |
| |
2008/11/12 Steven Rostedt <rostedt@goodmis.org>: > Impact: rename of debugfs file trace_entries to buffer_size > > 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" (thanks to Arjan van de Ven for this idea). > > Signed-off-by: Steven Rostedt <srostedt@redhat.com> > --- > Documentation/ftrace.txt | 18 +++++++++--------- > kernel/trace/trace.c | 4 ++-- > 2 files changed, 11 insertions(+), 11 deletions(-) > > diff --git a/Documentation/ftrace.txt b/Documentation/ftrace.txt > index 9cc4d68..58cba1f 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: > only be recorded if the latency is greater than > the value in this file. (in microseconds) > > - trace_entries: This sets or displays the number of bytes each CPU > + buffer_size: This sets or displays the number of bytes each CPU > buffer can hold. The tracer buffers are the same size > for each CPU. The displayed number is the size of the > CPU buffer and not total size of all buffers. The > @@ -1299,13 +1299,13 @@ trace entries > ------------- > > Having too much or not enough data can be troublesome in diagnosing > -an issue in the kernel. The file trace_entries is used to modify > +an issue in the kernel. The file buffer_size is used to modify > the size of the internal trace buffers. The number listed > is the number of entries that can be recorded per CPU. To know > the full size, multiply the number of possible CPUS with the > number of entries. > > - # cat /debug/tracing/trace_entries > + # cat /debug/tracing/buffer_size > 65620 > > 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 > to "nop", an EINVAL error will be returned. > > # echo nop > /debug/tracing/current_tracer > - # echo 100000 > /debug/tracing/trace_entries > - # cat /debug/tracing/trace_entries > + # echo 100000 > /debug/tracing/buffer_size > + # cat /debug/tracing/buffer_size > 100045 > > > @@ -1323,8 +1323,8 @@ are held in individual pages. It allocates the number of pages it takes > to fulfill the request. If more entries may fit on the last page > then they will be added. > > - # echo 1 > /debug/tracing/trace_entries > - # cat /debug/tracing/trace_entries > + # echo 1 > /debug/tracing/buffer_size > + # cat /debug/tracing/buffer_size > 85 > > 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. > The number of pages which will be allocated is limited to a percentage > of available memory. Allocating too much will produce an error. > > - # echo 1000000000000 > /debug/tracing/trace_entries > + # echo 1000000000000 > /debug/tracing/buffer_size > -bash: echo: write error: Cannot allocate memory > - # cat /debug/tracing/trace_entries > + # cat /debug/tracing/buffer_size > 85 > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 4bf070b..c681778 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -3198,11 +3198,11 @@ static __init int tracer_init_debugfs(void) > pr_warning("Could not create debugfs " > "'trace_pipe' entry\n"); > > - entry = debugfs_create_file("trace_entries", 0644, d_tracer, > + entry = debugfs_create_file("buffer_size", 0644, d_tracer, > &global_trace, &tracing_entries_fops); > if (!entry) > pr_warning("Could not create debugfs " > - "'trace_entries' entry\n"); > + "'buffer_size' entry\n"); > > entry = debugfs_create_file("trace_marker", 0220, d_tracer, > NULL, &tracing_mark_fops); > -- > 1.5.6.5 > > -- >
Yes this name is much more obvious.
| |