| Message ID | 20210313064149.29276-6-huangpei@loongson.cn (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/6] MIPS: replace -pg with CC_FLAGS_FTRACE | expand |
Hello! On 3/13/21 9:41 AM, Huang Pei wrote: > From: Jisheng Zhang <Jisheng.Zhang@synaptics.com> > > On some architectures, the DYNAMIC_FTRACE_WITH_REGS is implemented by > gcc's -fpatchable-function-entry option. Take arm64 for example, arm64 > makes use of GCC -fpatchable-function-entry=2 option to insert two > nops. When the function is traced, the first nop will be modified to > the LR saver, then the second nop to "bl <ftrace-entry>". we need to > update ftrace_location() to recognise these two instructions as being > part of ftrace. To do this, we introduce FTRACE_IP_EXTENSION to let > ftrace_location search IP, IP + FTRACE_IP_EXTENSION range. > > Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> > Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> > --- > include/linux/ftrace.h | 4 ++++ > kernel/trace/ftrace.c | 2 +- > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h > index 1bd3a0356ae4..c1e1fbde8a04 100644 > --- a/include/linux/ftrace.h > +++ b/include/linux/ftrace.h > @@ -20,6 +20,10 @@ > > #include <asm/ftrace.h> > > +#ifndef FTRACE_IP_EXTENSION > +#define FTRACE_IP_EXTENSION 0 Inconsistent spacing between #<directive> and the value? [...] MBR, Sergei
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 1bd3a0356ae4..c1e1fbde8a04 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -20,6 +20,10 @@ #include <asm/ftrace.h> +#ifndef FTRACE_IP_EXTENSION +#define FTRACE_IP_EXTENSION 0 +#endif + /* * If the arch supports passing the variable contents of * function_trace_op as the third parameter back from the diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 9c1bba8cc51b..a6f0e3db2479 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1583,7 +1583,7 @@ unsigned long ftrace_location_range(unsigned long start, unsigned long end) */ unsigned long ftrace_location(unsigned long ip) { - return ftrace_location_range(ip, ip); + return ftrace_location_range(ip, ip + FTRACE_IP_EXTENSION); } /**