2021-10-08 12:13:36 +03:00
// SPDX-License-Identifier: GPL-2.0-only
# include <linux/module.h>
# include <linux/mm.h> /* for handle_mm_fault() */
# include <linux/ftrace.h>
# include <linux/sched/stat.h>
2021-11-15 22:56:14 +03:00
# include <asm/asm-offsets.h>
2021-10-08 12:13:36 +03:00
2021-11-01 18:39:07 +03:00
extern void my_direct_func ( unsigned long ip ) ;
2021-10-08 12:13:36 +03:00
void my_direct_func ( unsigned long ip )
{
trace_printk ( " ip %lx \n " , ip ) ;
}
extern void my_tramp ( void * ) ;
2021-11-15 22:56:14 +03:00
# ifdef CONFIG_X86_64
2022-03-08 18:30:34 +03:00
# include <asm/ibt.h>
2023-01-30 11:59:54 +03:00
# include <asm/nospec-branch.h>
2022-03-08 18:30:34 +03:00
2021-10-08 12:13:36 +03:00
asm (
" .pushsection .text, \" ax \" , @progbits \n "
" .type my_tramp, @function \n "
" .globl my_tramp \n "
" my_tramp: "
2022-03-08 18:30:34 +03:00
ASM_ENDBR
2021-10-08 12:13:36 +03:00
" pushq %rbp \n "
" movq %rsp, %rbp \n "
2022-09-15 14:11:37 +03:00
CALL_DEPTH_ACCOUNT
2021-10-08 12:13:36 +03:00
" pushq %rdi \n "
" movq 8(%rbp), %rdi \n "
" call my_direct_func \n "
" popq %rdi \n "
" leave \n "
2022-03-08 18:30:34 +03:00
ASM_RET
2021-10-08 12:13:36 +03:00
" .size my_tramp, .-my_tramp \n "
" .popsection \n "
) ;
2021-11-15 22:56:14 +03:00
# endif /* CONFIG_X86_64 */
# ifdef CONFIG_S390
asm (
" .pushsection .text, \" ax \" , @progbits \n "
" .type my_tramp, @function \n "
" .globl my_tramp \n "
" my_tramp: "
" lgr %r1,%r15 \n "
" stmg %r0,%r5, " __stringify ( __SF_GPRS ) " (%r15) \n "
" stg %r14, " __stringify ( __SF_GPRS + 8 * 8 ) " (%r15) \n "
" aghi %r15, " __stringify ( - STACK_FRAME_OVERHEAD ) " \n "
" stg %r1, " __stringify ( __SF_BACKCHAIN ) " (%r15) \n "
" lgr %r2,%r0 \n "
" brasl %r14,my_direct_func \n "
" aghi %r15, " __stringify ( STACK_FRAME_OVERHEAD ) " \n "
" lmg %r0,%r5, " __stringify ( __SF_GPRS ) " (%r15) \n "
" lg %r14, " __stringify ( __SF_GPRS + 8 * 8 ) " (%r15) \n "
" lgr %r1,%r0 \n "
" br %r1 \n "
" .size my_tramp, .-my_tramp \n "
" .popsection \n "
) ;
# endif /* CONFIG_S390 */
2023-05-01 12:19:53 +03:00
# ifdef CONFIG_LOONGARCH
# include <asm/asm.h>
asm (
" .pushsection .text, \" ax \" , @progbits \n "
" .type my_tramp, @function \n "
" .globl my_tramp \n "
" my_tramp: \n "
" addi.d $sp, $sp, -32 \n "
" st.d $a0, $sp, 0 \n "
" st.d $t0, $sp, 8 \n "
" st.d $ra, $sp, 16 \n "
" move $a0, $t0 \n "
" bl my_direct_func \n "
" ld.d $a0, $sp, 0 \n "
" ld.d $t0, $sp, 8 \n "
" ld.d $ra, $sp, 16 \n "
" addi.d $sp, $sp, 32 \n "
" jr $t0 \n "
" .size my_tramp, .-my_tramp \n "
" .popsection \n "
) ;
# endif /* CONFIG_LOONGARCH */
2021-10-08 12:13:36 +03:00
static struct ftrace_ops direct ;
static int __init ftrace_direct_multi_init ( void )
{
ftrace_set_filter_ip ( & direct , ( unsigned long ) wake_up_process , 0 , 0 ) ;
ftrace_set_filter_ip ( & direct , ( unsigned long ) schedule , 0 , 0 ) ;
2023-03-21 17:04:21 +03:00
return register_ftrace_direct ( & direct , ( unsigned long ) my_tramp ) ;
2021-10-08 12:13:36 +03:00
}
static void __exit ftrace_direct_multi_exit ( void )
{
2023-03-21 17:04:21 +03:00
unregister_ftrace_direct ( & direct , ( unsigned long ) my_tramp , true ) ;
2021-10-08 12:13:36 +03:00
}
module_init ( ftrace_direct_multi_init ) ;
module_exit ( ftrace_direct_multi_exit ) ;
MODULE_AUTHOR ( " Jiri Olsa " ) ;
MODULE_DESCRIPTION ( " Example use case of using register_ftrace_direct_multi() " ) ;
MODULE_LICENSE ( " GPL " ) ;