Unverified Commit 500e626c authored by Andy Chiu's avatar Andy Chiu Committed by Palmer Dabbelt
Browse files

kernel: ftrace: export ftrace_sync_ipi 



The following ftrace patch for riscv uses a data store to update ftrace
function. Therefore, a romote fence is required to order it against
function_trace_op updates. The mechanism is similar to the fence between
function_trace_op and update_ftrace_func in the generic ftrace, so we
leverage the same ftrace_sync_ipi function.

[ alex: Fix build warning when !CONFIG_DYNAMIC_FTRACE ]

Signed-off-by: default avatarAndy Chiu <andybnac@gmail.com>
Link: https://lore.kernel.org/r/20250407180838.42877-4-andybnac@gmail.com


Signed-off-by: default avatarAlexandre Ghiti <alexghiti@rivosinc.com>
Signed-off-by: default avatarPalmer Dabbelt <palmer@dabbelt.com>
parent c41bf432

include/linux/ftrace.h

+2 −0
Original line number Diff line number Diff line
@@ -635,6 +635,8 @@ enum { 
#define ftrace_get_symaddr(fentry_ip) (0)

#endif



void ftrace_sync_ipi(void *data);



#ifdef CONFIG_DYNAMIC_FTRACE



void ftrace_arch_code_modify_prepare(void);

kernel/trace/ftrace.c

+1 −1
Original line number Diff line number Diff line
@@ -188,7 +188,7 @@ static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, 
	op->saved_func(ip, parent_ip, op, fregs);

}



static void ftrace_sync_ipi(void *data)

void ftrace_sync_ipi(void *data)

{

	/* Probably not needed, but do it anyway */

	smp_rmb();