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Diffstat (limited to 'Documentation/trace/ftrace-design.txt')
| -rw-r--r-- | Documentation/trace/ftrace-design.txt | 26 |
1 files changed, 0 insertions, 26 deletions
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt index 3f669b9e8852..dd5f916b351d 100644 --- a/Documentation/trace/ftrace-design.txt +++ b/Documentation/trace/ftrace-design.txt @@ -102,30 +102,6 @@ extern void mcount(void); EXPORT_SYMBOL(mcount); -HAVE_FUNCTION_TRACE_MCOUNT_TEST -------------------------------- - -This is an optional optimization for the normal case when tracing is turned off -in the system. If you do not enable this Kconfig option, the common ftrace -code will take care of doing the checking for you. - -To support this feature, you only need to check the function_trace_stop -variable in the mcount function. If it is non-zero, there is no tracing to be -done at all, so you can return. - -This additional pseudo code would simply be: -void mcount(void) -{ - /* save any bare state needed in order to do initial checking */ - -+ if (function_trace_stop) -+ return; - - extern void (*ftrace_trace_function)(unsigned long, unsigned long); - if (ftrace_trace_function != ftrace_stub) -... - - HAVE_FUNCTION_GRAPH_TRACER -------------------------- @@ -328,8 +304,6 @@ void mcount(void) void ftrace_caller(void) { - /* implement HAVE_FUNCTION_TRACE_MCOUNT_TEST if you desire */ - /* save all state needed by the ABI (see paragraph above) */ unsigned long frompc = ...; |