Kernel/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-01-15 17:43:59 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

s390/ftrace: fix compile error if CONFIG_KPROBES is disabled

Browse Source 
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Heiko Carstens 2015-03-13 10:31:42 +01:00 committed by Martin Schwidefsky
parent 0a64815091
commit 20e76ee184
1 changed files with 45 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
arch/s390/kernel/ftrace.c
View File

@ -57,6 +57,44 @@
unsigned long ftrace_plt; unsigned long ftrace_plt;
static inline void ftrace_generate_orig_insn(struct ftrace_insn *insn)
{
#ifdef CC_USING_HOTPATCH
/* brcl 0,0 */
insn->opc = 0xc004;
insn->disp = 0;
#else
/* stg r14,8(r15) */
insn->opc = 0xe3e0;
insn->disp = 0xf0080024;
#endif
}
static inline int is_kprobe_on_ftrace(struct ftrace_insn *insn)
{
#ifdef CONFIG_KPROBES
if (insn->opc == BREAKPOINT_INSTRUCTION)
return 1;
#endif
return 0;
}
static inline void ftrace_generate_kprobe_nop_insn(struct ftrace_insn *insn)
{
#ifdef CONFIG_KPROBES
insn->opc = BREAKPOINT_INSTRUCTION;
insn->disp = KPROBE_ON_FTRACE_NOP;
#endif
}
static inline void ftrace_generate_kprobe_call_insn(struct ftrace_insn *insn)
{
#ifdef CONFIG_KPROBES
insn->opc = BREAKPOINT_INSTRUCTION;
insn->disp = KPROBE_ON_FTRACE_CALL;
#endif
}
int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
unsigned long addr) unsigned long addr)
{ {
@ -72,16 +110,9 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
return -EFAULT; return -EFAULT;
if (addr == MCOUNT_ADDR) { if (addr == MCOUNT_ADDR) {
/* Initial code replacement */ /* Initial code replacement */
#ifdef CC_USING_HOTPATCH ftrace_generate_orig_insn(&orig);
/* We expect to see brcl 0,0 */
ftrace_generate_nop_insn(&orig);
#else
/* We expect to see stg r14,8(r15) */
orig.opc = 0xe3e0;
orig.disp = 0xf0080024;
#endif
ftrace_generate_nop_insn(&new); ftrace_generate_nop_insn(&new);
} else if (old.opc == BREAKPOINT_INSTRUCTION) { } else if (is_kprobe_on_ftrace(&old)) {
/* /*
* If we find a breakpoint instruction, a kprobe has been * If we find a breakpoint instruction, a kprobe has been
* placed at the beginning of the function. We write the * placed at the beginning of the function. We write the
@ -89,9 +120,8 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
* bytes of the original instruction so that the kprobes * bytes of the original instruction so that the kprobes
* handler can execute a nop, if it reaches this breakpoint. * handler can execute a nop, if it reaches this breakpoint.
*/ */
new.opc = orig.opc = BREAKPOINT_INSTRUCTION; ftrace_generate_kprobe_call_insn(&orig);
orig.disp = KPROBE_ON_FTRACE_CALL; ftrace_generate_kprobe_nop_insn(&new);
new.disp = KPROBE_ON_FTRACE_NOP;
} else { } else {
/* Replace ftrace call with a nop. */ /* Replace ftrace call with a nop. */
ftrace_generate_call_insn(&orig, rec->ip); ftrace_generate_call_insn(&orig, rec->ip);
@ -111,7 +141,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
if (probe_kernel_read(&old, (void *) rec->ip, sizeof(old))) if (probe_kernel_read(&old, (void *) rec->ip, sizeof(old)))
return -EFAULT; return -EFAULT;
if (old.opc == BREAKPOINT_INSTRUCTION) { if (is_kprobe_on_ftrace(&old)) {
/* /*
* If we find a breakpoint instruction, a kprobe has been * If we find a breakpoint instruction, a kprobe has been
* placed at the beginning of the function. We write the * placed at the beginning of the function. We write the
@ -119,9 +149,8 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
* bytes of the original instruction so that the kprobes * bytes of the original instruction so that the kprobes
* handler can execute a brasl if it reaches this breakpoint. * handler can execute a brasl if it reaches this breakpoint.
*/ */
new.opc = orig.opc = BREAKPOINT_INSTRUCTION; ftrace_generate_kprobe_nop_insn(&orig);
orig.disp = KPROBE_ON_FTRACE_NOP; ftrace_generate_kprobe_call_insn(&new);
new.disp = KPROBE_ON_FTRACE_CALL;
} else { } else {
/* Replace nop with an ftrace call. */ /* Replace nop with an ftrace call. */
ftrace_generate_nop_insn(&orig); ftrace_generate_nop_insn(&orig);