mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
synced 2024-12-28 16:52:18 +00:00
71db948b9d
Add powerpc 32-bit and 64-bit samples for ftrace direct. This serves to show the sample instruction sequence to be used by ftrace direct calls to adhere to the ftrace ABI. On 64-bit powerpc, TOC setup requires some additional work. Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241030070850.1361304-17-hbathini@linux.ibm.com
242 lines
5.5 KiB
C
242 lines
5.5 KiB
C
// 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>
|
|
#if !defined(CONFIG_ARM64) && !defined(CONFIG_PPC32)
|
|
#include <asm/asm-offsets.h>
|
|
#endif
|
|
|
|
extern void my_direct_func(unsigned long ip);
|
|
|
|
void my_direct_func(unsigned long ip)
|
|
{
|
|
trace_printk("ip %lx\n", ip);
|
|
}
|
|
|
|
extern void my_tramp(void *);
|
|
|
|
#ifdef CONFIG_RISCV
|
|
#include <asm/asm.h>
|
|
|
|
asm (
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
" .type my_tramp, @function\n"
|
|
" .globl my_tramp\n"
|
|
" my_tramp:\n"
|
|
" addi sp,sp,-3*"SZREG"\n"
|
|
" "REG_S" a0,0*"SZREG"(sp)\n"
|
|
" "REG_S" t0,1*"SZREG"(sp)\n"
|
|
" "REG_S" ra,2*"SZREG"(sp)\n"
|
|
" mv a0,t0\n"
|
|
" call my_direct_func\n"
|
|
" "REG_L" a0,0*"SZREG"(sp)\n"
|
|
" "REG_L" t0,1*"SZREG"(sp)\n"
|
|
" "REG_L" ra,2*"SZREG"(sp)\n"
|
|
" addi sp,sp,3*"SZREG"\n"
|
|
" jr t0\n"
|
|
" .size my_tramp, .-my_tramp\n"
|
|
" .popsection\n"
|
|
);
|
|
|
|
#endif /* CONFIG_RISCV */
|
|
|
|
#ifdef CONFIG_X86_64
|
|
|
|
#include <asm/ibt.h>
|
|
#include <asm/nospec-branch.h>
|
|
|
|
asm (
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
" .type my_tramp, @function\n"
|
|
" .globl my_tramp\n"
|
|
" my_tramp:"
|
|
ASM_ENDBR
|
|
" pushq %rbp\n"
|
|
" movq %rsp, %rbp\n"
|
|
CALL_DEPTH_ACCOUNT
|
|
" pushq %rdi\n"
|
|
" movq 8(%rbp), %rdi\n"
|
|
" call my_direct_func\n"
|
|
" popq %rdi\n"
|
|
" leave\n"
|
|
ASM_RET
|
|
" .size my_tramp, .-my_tramp\n"
|
|
" .popsection\n"
|
|
);
|
|
|
|
#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 */
|
|
|
|
#ifdef CONFIG_ARM64
|
|
|
|
asm (
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
" .type my_tramp, @function\n"
|
|
" .globl my_tramp\n"
|
|
" my_tramp:"
|
|
" hint 34\n" // bti c
|
|
" sub sp, sp, #32\n"
|
|
" stp x9, x30, [sp]\n"
|
|
" str x0, [sp, #16]\n"
|
|
" mov x0, x30\n"
|
|
" bl my_direct_func\n"
|
|
" ldp x30, x9, [sp]\n"
|
|
" ldr x0, [sp, #16]\n"
|
|
" add sp, sp, #32\n"
|
|
" ret x9\n"
|
|
" .size my_tramp, .-my_tramp\n"
|
|
" .popsection\n"
|
|
);
|
|
|
|
#endif /* CONFIG_ARM64 */
|
|
|
|
#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 */
|
|
|
|
#ifdef CONFIG_PPC
|
|
#include <asm/ppc_asm.h>
|
|
|
|
#ifdef CONFIG_PPC64
|
|
#define STACK_FRAME_SIZE 48
|
|
#else
|
|
#define STACK_FRAME_SIZE 24
|
|
#endif
|
|
|
|
#if defined(CONFIG_PPC64_ELF_ABI_V2) && !defined(CONFIG_PPC_KERNEL_PCREL)
|
|
#define PPC64_TOC_SAVE_AND_UPDATE \
|
|
" std 2, 24(1)\n" \
|
|
" bcl 20, 31, 1f\n" \
|
|
" 1: mflr 12\n" \
|
|
" ld 2, (99f - 1b)(12)\n"
|
|
#define PPC64_TOC_RESTORE \
|
|
" ld 2, 24(1)\n"
|
|
#define PPC64_TOC \
|
|
" 99: .quad .TOC.@tocbase\n"
|
|
#else
|
|
#define PPC64_TOC_SAVE_AND_UPDATE ""
|
|
#define PPC64_TOC_RESTORE ""
|
|
#define PPC64_TOC ""
|
|
#endif
|
|
|
|
#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
|
|
#define PPC_FTRACE_RESTORE_LR \
|
|
PPC_LL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n" \
|
|
" mtlr 0\n"
|
|
#define PPC_FTRACE_RET \
|
|
" blr\n"
|
|
#define PPC_FTRACE_RECOVER_IP \
|
|
" lwz 8, 4(3)\n" \
|
|
" li 9, 6\n" \
|
|
" slw 8, 8, 9\n" \
|
|
" sraw 8, 8, 9\n" \
|
|
" add 3, 3, 8\n" \
|
|
" addi 3, 3, 4\n"
|
|
#else
|
|
#define PPC_FTRACE_RESTORE_LR \
|
|
PPC_LL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n" \
|
|
" mtctr 0\n"
|
|
#define PPC_FTRACE_RET \
|
|
" mtlr 0\n" \
|
|
" bctr\n"
|
|
#define PPC_FTRACE_RECOVER_IP ""
|
|
#endif
|
|
|
|
asm (
|
|
" .pushsection .text, \"ax\", @progbits\n"
|
|
" .type my_tramp, @function\n"
|
|
" .globl my_tramp\n"
|
|
" my_tramp:\n"
|
|
PPC_STL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
PPC_STLU" 1, -"__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
" mflr 0\n"
|
|
PPC_STL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
PPC_STLU" 1, -"__stringify(STACK_FRAME_SIZE)"(1)\n"
|
|
PPC64_TOC_SAVE_AND_UPDATE
|
|
PPC_STL" 3, "__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
" mr 3, 0\n"
|
|
PPC_FTRACE_RECOVER_IP
|
|
" bl my_direct_func\n"
|
|
PPC_LL" 3, "__stringify(STACK_FRAME_MIN_SIZE)"(1)\n"
|
|
PPC64_TOC_RESTORE
|
|
" addi 1, 1, "__stringify(STACK_FRAME_SIZE)"\n"
|
|
PPC_FTRACE_RESTORE_LR
|
|
" addi 1, 1, "__stringify(STACK_FRAME_MIN_SIZE)"\n"
|
|
PPC_LL" 0, "__stringify(PPC_LR_STKOFF)"(1)\n"
|
|
PPC_FTRACE_RET
|
|
PPC64_TOC
|
|
" .size my_tramp, .-my_tramp\n"
|
|
" .popsection\n"
|
|
);
|
|
|
|
#endif /* CONFIG_PPC */
|
|
|
|
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);
|
|
|
|
return register_ftrace_direct(&direct, (unsigned long) my_tramp);
|
|
}
|
|
|
|
static void __exit ftrace_direct_multi_exit(void)
|
|
{
|
|
unregister_ftrace_direct(&direct, (unsigned long) my_tramp, true);
|
|
}
|
|
|
|
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");
|