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-rw-r--r--arch/powerpc/kernel/trace/ftrace.c212
-rw-r--r--arch/powerpc/kernel/trace/ftrace_32.S20
-rw-r--r--arch/powerpc/kernel/trace/ftrace_64.S29
-rw-r--r--arch/powerpc/kernel/trace/ftrace_64_mprofile.S88
-rw-r--r--arch/powerpc/kernel/trace/ftrace_64_pg.S6
5 files changed, 251 insertions, 104 deletions
diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
index 4741fe112f05..c076a32093fd 100644
--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -357,6 +357,8 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
{
unsigned int op[2];
void *ip = (void *)rec->ip;
+ unsigned long entry, ptr, tramp;
+ struct module *mod = rec->arch.mod;
/* read where this goes */
if (probe_kernel_read(op, ip, sizeof(op)))
@@ -368,19 +370,44 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
return -EINVAL;
}
- /* If we never set up a trampoline to ftrace_caller, then bail */
- if (!rec->arch.mod->arch.tramp) {
+ /* If we never set up ftrace trampoline(s), then bail */
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+ if (!mod->arch.tramp || !mod->arch.tramp_regs) {
+#else
+ if (!mod->arch.tramp) {
+#endif
pr_err("No ftrace trampoline\n");
return -EINVAL;
}
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+ if (rec->flags & FTRACE_FL_REGS)
+ tramp = mod->arch.tramp_regs;
+ else
+#endif
+ tramp = mod->arch.tramp;
+
+ if (module_trampoline_target(mod, tramp, &ptr)) {
+ pr_err("Failed to get trampoline target\n");
+ return -EFAULT;
+ }
+
+ pr_devel("trampoline target %lx", ptr);
+
+ entry = ppc_global_function_entry((void *)addr);
+ /* This should match what was called */
+ if (ptr != entry) {
+ pr_err("addr %lx does not match expected %lx\n", ptr, entry);
+ return -EINVAL;
+ }
+
/* Ensure branch is within 24 bits */
- if (!create_branch(ip, rec->arch.mod->arch.tramp, BRANCH_SET_LINK)) {
+ if (!create_branch(ip, tramp, BRANCH_SET_LINK)) {
pr_err("Branch out of range\n");
return -EINVAL;
}
- if (patch_branch(ip, rec->arch.mod->arch.tramp, BRANCH_SET_LINK)) {
+ if (patch_branch(ip, tramp, BRANCH_SET_LINK)) {
pr_err("REL24 out of range!\n");
return -EINVAL;
}
@@ -388,14 +415,6 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
return 0;
}
-#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
-int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
- unsigned long addr)
-{
- return ftrace_make_call(rec, addr);
-}
-#endif
-
#else /* !CONFIG_PPC64: */
static int
__ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
@@ -472,53 +491,158 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
#endif /* CONFIG_MODULES */
}
-int ftrace_update_ftrace_func(ftrace_func_t func)
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+#ifdef CONFIG_MODULES
+static int
+__ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
+ unsigned long addr)
{
- unsigned long ip = (unsigned long)(&ftrace_call);
- unsigned int old, new;
- int ret;
+ unsigned int op;
+ unsigned long ip = rec->ip;
+ unsigned long entry, ptr, tramp;
+ struct module *mod = rec->arch.mod;
- old = *(unsigned int *)&ftrace_call;
- new = ftrace_call_replace(ip, (unsigned long)func, 1);
- ret = ftrace_modify_code(ip, old, new);
+ /* If we never set up ftrace trampolines, then bail */
+ if (!mod->arch.tramp || !mod->arch.tramp_regs) {
+ pr_err("No ftrace trampoline\n");
+ return -EINVAL;
+ }
- return ret;
-}
+ /* read where this goes */
+ if (probe_kernel_read(&op, (void *)ip, sizeof(int))) {
+ pr_err("Fetching opcode failed.\n");
+ return -EFAULT;
+ }
-static int __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
-{
- unsigned long ftrace_addr = (unsigned long)FTRACE_ADDR;
- int ret;
+ /* Make sure that that this is still a 24bit jump */
+ if (!is_bl_op(op)) {
+ pr_err("Not expected bl: opcode is %x\n", op);
+ return -EINVAL;
+ }
+
+ /* lets find where the pointer goes */
+ tramp = find_bl_target(ip, op);
+ entry = ppc_global_function_entry((void *)old_addr);
+
+ pr_devel("ip:%lx jumps to %lx", ip, tramp);
- ret = ftrace_update_record(rec, enable);
+ if (tramp != entry) {
+ /* old_addr is not within range, so we must have used a trampoline */
+ if (module_trampoline_target(mod, tramp, &ptr)) {
+ pr_err("Failed to get trampoline target\n");
+ return -EFAULT;
+ }
+
+ pr_devel("trampoline target %lx", ptr);
+
+ /* This should match what was called */
+ if (ptr != entry) {
+ pr_err("addr %lx does not match expected %lx\n", ptr, entry);
+ return -EINVAL;
+ }
+ }
+
+ /* The new target may be within range */
+ if (test_24bit_addr(ip, addr)) {
+ /* within range */
+ if (patch_branch((unsigned int *)ip, addr, BRANCH_SET_LINK)) {
+ pr_err("REL24 out of range!\n");
+ return -EINVAL;
+ }
- switch (ret) {
- case FTRACE_UPDATE_IGNORE:
return 0;
- case FTRACE_UPDATE_MAKE_CALL:
- return ftrace_make_call(rec, ftrace_addr);
- case FTRACE_UPDATE_MAKE_NOP:
- return ftrace_make_nop(NULL, rec, ftrace_addr);
+ }
+
+ if (rec->flags & FTRACE_FL_REGS)
+ tramp = mod->arch.tramp_regs;
+ else
+ tramp = mod->arch.tramp;
+
+ if (module_trampoline_target(mod, tramp, &ptr)) {
+ pr_err("Failed to get trampoline target\n");
+ return -EFAULT;
+ }
+
+ pr_devel("trampoline target %lx", ptr);
+
+ entry = ppc_global_function_entry((void *)addr);
+ /* This should match what was called */
+ if (ptr != entry) {
+ pr_err("addr %lx does not match expected %lx\n", ptr, entry);
+ return -EINVAL;
+ }
+
+ /* Ensure branch is within 24 bits */
+ if (!create_branch((unsigned int *)ip, tramp, BRANCH_SET_LINK)) {
+ pr_err("Branch out of range\n");
+ return -EINVAL;
+ }
+
+ if (patch_branch((unsigned int *)ip, tramp, BRANCH_SET_LINK)) {
+ pr_err("REL24 out of range!\n");
+ return -EINVAL;
}
return 0;
}
+#endif
-void ftrace_replace_code(int enable)
+int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
+ unsigned long addr)
{
- struct ftrace_rec_iter *iter;
- struct dyn_ftrace *rec;
+ unsigned long ip = rec->ip;
+ unsigned int old, new;
+
+ /*
+ * If the calling address is more that 24 bits away,
+ * then we had to use a trampoline to make the call.
+ * Otherwise just update the call site.
+ */
+ if (test_24bit_addr(ip, addr) && test_24bit_addr(ip, old_addr)) {
+ /* within range */
+ old = ftrace_call_replace(ip, old_addr, 1);
+ new = ftrace_call_replace(ip, addr, 1);
+ return ftrace_modify_code(ip, old, new);
+ }
+
+#ifdef CONFIG_MODULES
+ /*
+ * Out of range jumps are called from modules.
+ */
+ if (!rec->arch.mod) {
+ pr_err("No module loaded\n");
+ return -EINVAL;
+ }
+
+ return __ftrace_modify_call(rec, old_addr, addr);
+#else
+ /* We should not get here without modules */
+ return -EINVAL;
+#endif /* CONFIG_MODULES */
+}
+#endif
+
+int ftrace_update_ftrace_func(ftrace_func_t func)
+{
+ unsigned long ip = (unsigned long)(&ftrace_call);
+ unsigned int old, new;
int ret;
- for (iter = ftrace_rec_iter_start(); iter;
- iter = ftrace_rec_iter_next(iter)) {
- rec = ftrace_rec_iter_record(iter);
- ret = __ftrace_replace_code(rec, enable);
- if (ret) {
- ftrace_bug(ret, rec);
- return;
- }
+ old = *(unsigned int *)&ftrace_call;
+ new = ftrace_call_replace(ip, (unsigned long)func, 1);
+ ret = ftrace_modify_code(ip, old, new);
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
+ /* Also update the regs callback function */
+ if (!ret) {
+ ip = (unsigned long)(&ftrace_regs_call);
+ old = *(unsigned int *)&ftrace_regs_call;
+ new = ftrace_call_replace(ip, (unsigned long)func, 1);
+ ret = ftrace_modify_code(ip, old, new);
}
+#endif
+
+ return ret;
}
/*
@@ -538,7 +662,6 @@ int __init ftrace_dyn_arch_init(void)
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-#ifdef CONFIG_DYNAMIC_FTRACE
extern void ftrace_graph_call(void);
extern void ftrace_graph_stub(void);
@@ -567,7 +690,6 @@ int ftrace_disable_ftrace_graph_caller(void)
return ftrace_modify_code(ip, old, new);
}
-#endif /* CONFIG_DYNAMIC_FTRACE */
/*
* Hook the return address and push it in the stack of return addrs
diff --git a/arch/powerpc/kernel/trace/ftrace_32.S b/arch/powerpc/kernel/trace/ftrace_32.S
index afef2c076282..2c29098f630f 100644
--- a/arch/powerpc/kernel/trace/ftrace_32.S
+++ b/arch/powerpc/kernel/trace/ftrace_32.S
@@ -14,7 +14,6 @@
#include <asm/ftrace.h>
#include <asm/export.h>
-#ifdef CONFIG_DYNAMIC_FTRACE
_GLOBAL(mcount)
_GLOBAL(_mcount)
/*
@@ -47,26 +46,7 @@ _GLOBAL(ftrace_graph_stub)
MCOUNT_RESTORE_FRAME
/* old link register ends up in ctr reg */
bctr
-#else
-_GLOBAL(mcount)
-_GLOBAL(_mcount)
-
- MCOUNT_SAVE_FRAME
- subi r3, r3, MCOUNT_INSN_SIZE
- LOAD_REG_ADDR(r5, ftrace_trace_function)
- lwz r5,0(r5)
-
- mtctr r5
- bctrl
- nop
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
- b ftrace_graph_caller
-#endif
- MCOUNT_RESTORE_FRAME
- bctr
-#endif
EXPORT_SYMBOL(_mcount)
_GLOBAL(ftrace_stub)
diff --git a/arch/powerpc/kernel/trace/ftrace_64.S b/arch/powerpc/kernel/trace/ftrace_64.S
index e5ccea19821e..e25f77c10a72 100644
--- a/arch/powerpc/kernel/trace/ftrace_64.S
+++ b/arch/powerpc/kernel/trace/ftrace_64.S
@@ -14,7 +14,6 @@
#include <asm/ppc-opcode.h>
#include <asm/export.h>
-#ifdef CONFIG_DYNAMIC_FTRACE
_GLOBAL(mcount)
_GLOBAL(_mcount)
EXPORT_SYMBOL(_mcount)
@@ -23,34 +22,6 @@ EXPORT_SYMBOL(_mcount)
mtlr r0
bctr
-#else /* CONFIG_DYNAMIC_FTRACE */
-_GLOBAL_TOC(_mcount)
-EXPORT_SYMBOL(_mcount)
- /* Taken from output of objdump from lib64/glibc */
- mflr r3
- ld r11, 0(r1)
- stdu r1, -112(r1)
- std r3, 128(r1)
- ld r4, 16(r11)
-
- subi r3, r3, MCOUNT_INSN_SIZE
- LOAD_REG_ADDR(r5,ftrace_trace_function)
- ld r5,0(r5)
- ld r5,0(r5)
- mtctr r5
- bctrl
- nop
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
- b ftrace_graph_caller
-#endif
- ld r0, 128(r1)
- mtlr r0
- addi r1, r1, 112
-_GLOBAL(ftrace_stub)
- blr
-#endif /* CONFIG_DYNAMIC_FTRACE */
-
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(return_to_handler)
/* need to save return values */
diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index 3f3e81852422..9a5b5a513604 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -17,11 +17,10 @@
#include <asm/bug.h>
#include <asm/ptrace.h>
-#ifdef CONFIG_DYNAMIC_FTRACE
/*
*
- * ftrace_caller() is the function that replaces _mcount() when ftrace is
- * active.
+ * ftrace_caller()/ftrace_regs_caller() is the function that replaces _mcount()
+ * when ftrace is active.
*
* We arrive here after a function A calls function B, and we are the trace
* function for B. When we enter r1 points to A's stack frame, B has not yet
@@ -37,7 +36,7 @@
* Our job is to save the register state into a struct pt_regs (on the stack)
* and then arrange for the ftrace function to be called.
*/
-_GLOBAL(ftrace_caller)
+_GLOBAL(ftrace_regs_caller)
/* Save the original return address in A's stack frame */
std r0,LRSAVE(r1)
@@ -47,6 +46,12 @@ _GLOBAL(ftrace_caller)
/* Save all gprs to pt_regs */
SAVE_GPR(0, r1)
SAVE_10GPRS(2, r1)
+
+ /* Ok to continue? */
+ lbz r3, PACA_FTRACE_ENABLED(r13)
+ cmpdi r3, 0
+ beq ftrace_no_trace
+
SAVE_10GPRS(12, r1)
SAVE_10GPRS(22, r1)
@@ -94,8 +99,8 @@ _GLOBAL(ftrace_caller)
addi r6, r1 ,STACK_FRAME_OVERHEAD
/* ftrace_call(r3, r4, r5, r6) */
-.globl ftrace_call
-ftrace_call:
+.globl ftrace_regs_call
+ftrace_regs_call:
bl ftrace_stub
nop
@@ -156,6 +161,7 @@ ftrace_call:
bne- livepatch_handler
#endif
+ftrace_caller_common:
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
.globl ftrace_graph_call
ftrace_graph_call:
@@ -168,6 +174,74 @@ _GLOBAL(ftrace_graph_stub)
_GLOBAL(ftrace_stub)
blr
+ftrace_no_trace:
+ mflr r3
+ mtctr r3
+ REST_GPR(3, r1)
+ addi r1, r1, SWITCH_FRAME_SIZE
+ mtlr r0
+ bctr
+
+_GLOBAL(ftrace_caller)
+ /* Save the original return address in A's stack frame */
+ std r0, LRSAVE(r1)
+
+ /* Create our stack frame + pt_regs */
+ stdu r1, -SWITCH_FRAME_SIZE(r1)
+
+ /* Save all gprs to pt_regs */
+ SAVE_8GPRS(3, r1)
+
+ lbz r3, PACA_FTRACE_ENABLED(r13)
+ cmpdi r3, 0
+ beq ftrace_no_trace
+
+ /* Get the _mcount() call site out of LR */
+ mflr r7
+ std r7, _NIP(r1)
+
+ /* Save callee's TOC in the ABI compliant location */
+ std r2, 24(r1)
+ ld r2, PACATOC(r13) /* get kernel TOC in r2 */
+
+ addis r3, r2, function_trace_op@toc@ha
+ addi r3, r3, function_trace_op@toc@l
+ ld r5, 0(r3)
+
+ /* Calculate ip from nip-4 into r3 for call below */
+ subi r3, r7, MCOUNT_INSN_SIZE
+
+ /* Put the original return address in r4 as parent_ip */
+ mr r4, r0
+
+ /* Set pt_regs to NULL */
+ li r6, 0
+
+ /* ftrace_call(r3, r4, r5, r6) */
+.globl ftrace_call
+ftrace_call:
+ bl ftrace_stub
+ nop
+
+ ld r3, _NIP(r1)
+ mtctr r3
+
+ /* Restore gprs */
+ REST_8GPRS(3,r1)
+
+ /* Restore callee's TOC */
+ ld r2, 24(r1)
+
+ /* Pop our stack frame */
+ addi r1, r1, SWITCH_FRAME_SIZE
+
+ /* Reload original LR */
+ ld r0, LRSAVE(r1)
+ mtlr r0
+
+ /* Handle function_graph or go back */
+ b ftrace_caller_common
+
#ifdef CONFIG_LIVEPATCH
/*
* This function runs in the mcount context, between two functions. As
@@ -236,8 +310,6 @@ livepatch_handler:
blr
#endif /* CONFIG_LIVEPATCH */
-#endif /* CONFIG_DYNAMIC_FTRACE */
-
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(ftrace_graph_caller)
stdu r1, -112(r1)
diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.S b/arch/powerpc/kernel/trace/ftrace_64_pg.S
index f095358da96e..4c515c4023de 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_pg.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_pg.S
@@ -14,8 +14,11 @@
#include <asm/ppc-opcode.h>
#include <asm/export.h>
-#ifdef CONFIG_DYNAMIC_FTRACE
_GLOBAL_TOC(ftrace_caller)
+ lbz r3, PACA_FTRACE_ENABLED(r13)
+ cmpdi r3, 0
+ beqlr
+
/* Taken from output of objdump from lib64/glibc */
mflr r3
ld r11, 0(r1)
@@ -39,7 +42,6 @@ _GLOBAL(ftrace_graph_stub)
_GLOBAL(ftrace_stub)
blr
-#endif /* CONFIG_DYNAMIC_FTRACE */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
_GLOBAL(ftrace_graph_caller)