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-rw-r--r--arch/powerpc/kernel/trace/Makefile11
-rw-r--r--arch/powerpc/kernel/trace/ftrace.c310
-rw-r--r--arch/powerpc/kernel/trace/ftrace_64_pg.c85
-rw-r--r--arch/powerpc/kernel/trace/ftrace_entry.S244
4 files changed, 506 insertions, 144 deletions
diff --git a/arch/powerpc/kernel/trace/Makefile b/arch/powerpc/kernel/trace/Makefile
index 125f4ca588b9..d6c3885453bd 100644
--- a/arch/powerpc/kernel/trace/Makefile
+++ b/arch/powerpc/kernel/trace/Makefile
@@ -9,12 +9,15 @@ CFLAGS_REMOVE_ftrace.o = $(CC_FLAGS_FTRACE)
CFLAGS_REMOVE_ftrace_64_pg.o = $(CC_FLAGS_FTRACE)
endif
-obj32-$(CONFIG_FUNCTION_TRACER) += ftrace.o ftrace_entry.o
-ifdef CONFIG_MPROFILE_KERNEL
-obj64-$(CONFIG_FUNCTION_TRACER) += ftrace.o ftrace_entry.o
+ifdef CONFIG_FUNCTION_TRACER
+obj32-y += ftrace.o ftrace_entry.o
+ifeq ($(CONFIG_MPROFILE_KERNEL)$(CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY),)
+obj64-y += ftrace_64_pg.o ftrace_64_pg_entry.o
else
-obj64-$(CONFIG_FUNCTION_TRACER) += ftrace_64_pg.o ftrace_64_pg_entry.o
+obj64-y += ftrace.o ftrace_entry.o
+endif
endif
+
obj-$(CONFIG_TRACING) += trace_clock.o
obj-$(CONFIG_PPC64) += $(obj64-y)
diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
index d8d6b4fd9a14..6dca92d5a6e8 100644
--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -23,7 +23,7 @@
#include <linux/list.h>
#include <asm/cacheflush.h>
-#include <asm/code-patching.h>
+#include <asm/text-patching.h>
#include <asm/ftrace.h>
#include <asm/syscall.h>
#include <asm/inst.h>
@@ -37,8 +37,12 @@ unsigned long ftrace_call_adjust(unsigned long addr)
if (addr >= (unsigned long)__exittext_begin && addr < (unsigned long)__exittext_end)
return 0;
- if (IS_ENABLED(CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY))
+ if (IS_ENABLED(CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY) &&
+ !IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE)) {
addr += MCOUNT_INSN_SIZE;
+ if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS))
+ addr += MCOUNT_INSN_SIZE;
+ }
return addr;
}
@@ -82,7 +86,7 @@ static inline int ftrace_modify_code(unsigned long ip, ppc_inst_t old, ppc_inst_
{
int ret = ftrace_validate_inst(ip, old);
- if (!ret)
+ if (!ret && !ppc_inst_equal(old, new))
ret = patch_instruction((u32 *)ip, new);
return ret;
@@ -106,28 +110,66 @@ static unsigned long find_ftrace_tramp(unsigned long ip)
return 0;
}
+#ifdef CONFIG_MODULES
+static unsigned long ftrace_lookup_module_stub(unsigned long ip, unsigned long addr)
+{
+ struct module *mod = NULL;
+
+ scoped_guard(rcu)
+ mod = __module_text_address(ip);
+ if (!mod)
+ pr_err("No module loaded at addr=%lx\n", ip);
+
+ return (addr == (unsigned long)ftrace_caller ? mod->arch.tramp : mod->arch.tramp_regs);
+}
+#else
+static unsigned long ftrace_lookup_module_stub(unsigned long ip, unsigned long addr)
+{
+ return 0;
+}
+#endif
+
+static unsigned long ftrace_get_ool_stub(struct dyn_ftrace *rec)
+{
+#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
+ return rec->arch.ool_stub;
+#else
+ BUILD_BUG();
+#endif
+}
+
static int ftrace_get_call_inst(struct dyn_ftrace *rec, unsigned long addr, ppc_inst_t *call_inst)
{
- unsigned long ip = rec->ip;
+ unsigned long ip;
unsigned long stub;
- if (is_offset_in_branch_range(addr - ip)) {
+ if (IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE))
+ ip = ftrace_get_ool_stub(rec) + MCOUNT_INSN_SIZE; /* second instruction in stub */
+ else
+ ip = rec->ip;
+
+ if (!is_offset_in_branch_range(addr - ip) && addr != FTRACE_ADDR &&
+ addr != FTRACE_REGS_ADDR) {
+ /* This can only happen with ftrace direct */
+ if (!IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS)) {
+ pr_err("0x%lx (0x%lx): Unexpected target address 0x%lx\n",
+ ip, rec->ip, addr);
+ return -EINVAL;
+ }
+ addr = FTRACE_ADDR;
+ }
+
+ if (is_offset_in_branch_range(addr - ip))
/* Within range */
stub = addr;
-#ifdef CONFIG_MODULES
- } else if (rec->arch.mod) {
- /* Module code would be going to one of the module stubs */
- stub = (addr == (unsigned long)ftrace_caller ? rec->arch.mod->arch.tramp :
- rec->arch.mod->arch.tramp_regs);
-#endif
- } else if (core_kernel_text(ip)) {
+ else if (core_kernel_text(ip))
/* We would be branching to one of our ftrace stubs */
stub = find_ftrace_tramp(ip);
- if (!stub) {
- pr_err("0x%lx: No ftrace stubs reachable\n", ip);
- return -EINVAL;
- }
- } else {
+ else
+ stub = ftrace_lookup_module_stub(ip, addr);
+
+ if (!stub) {
+ pr_err("0x%lx (0x%lx): No ftrace stubs reachable\n", ip, rec->ip);
return -EINVAL;
}
@@ -135,6 +177,145 @@ static int ftrace_get_call_inst(struct dyn_ftrace *rec, unsigned long addr, ppc_
return 0;
}
+static int ftrace_init_ool_stub(struct module *mod, struct dyn_ftrace *rec)
+{
+#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
+ static int ool_stub_text_index, ool_stub_text_end_index, ool_stub_inittext_index;
+ int ret = 0, ool_stub_count, *ool_stub_index;
+ ppc_inst_t inst;
+ /*
+ * See ftrace_entry.S if changing the below instruction sequence, as we rely on
+ * decoding the last branch instruction here to recover the correct function ip.
+ */
+ struct ftrace_ool_stub *ool_stub, ool_stub_template = {
+ .insn = {
+ PPC_RAW_MFLR(_R0),
+ PPC_RAW_NOP(), /* bl ftrace_caller */
+ PPC_RAW_MTLR(_R0),
+ PPC_RAW_NOP() /* b rec->ip + 4 */
+ }
+ };
+
+ WARN_ON(rec->arch.ool_stub);
+
+ if (is_kernel_inittext(rec->ip)) {
+ ool_stub = ftrace_ool_stub_inittext;
+ ool_stub_index = &ool_stub_inittext_index;
+ ool_stub_count = ftrace_ool_stub_inittext_count;
+ } else if (is_kernel_text(rec->ip)) {
+ /*
+ * ftrace records are sorted, so we first use up the stub area within .text
+ * (ftrace_ool_stub_text) before using the area at the end of .text
+ * (ftrace_ool_stub_text_end), unless the stub is out of range of the record.
+ */
+ if (ool_stub_text_index >= ftrace_ool_stub_text_count ||
+ !is_offset_in_branch_range((long)rec->ip -
+ (long)&ftrace_ool_stub_text[ool_stub_text_index])) {
+ ool_stub = ftrace_ool_stub_text_end;
+ ool_stub_index = &ool_stub_text_end_index;
+ ool_stub_count = ftrace_ool_stub_text_end_count;
+ } else {
+ ool_stub = ftrace_ool_stub_text;
+ ool_stub_index = &ool_stub_text_index;
+ ool_stub_count = ftrace_ool_stub_text_count;
+ }
+#ifdef CONFIG_MODULES
+ } else if (mod) {
+ ool_stub = mod->arch.ool_stubs;
+ ool_stub_index = &mod->arch.ool_stub_index;
+ ool_stub_count = mod->arch.ool_stub_count;
+#endif
+ } else {
+ return -EINVAL;
+ }
+
+ ool_stub += (*ool_stub_index)++;
+
+ if (WARN_ON(*ool_stub_index > ool_stub_count))
+ return -EINVAL;
+
+ if (!is_offset_in_branch_range((long)rec->ip - (long)&ool_stub->insn[0]) ||
+ !is_offset_in_branch_range((long)(rec->ip + MCOUNT_INSN_SIZE) -
+ (long)&ool_stub->insn[3])) {
+ pr_err("%s: ftrace ool stub out of range (%p -> %p).\n",
+ __func__, (void *)rec->ip, (void *)&ool_stub->insn[0]);
+ return -EINVAL;
+ }
+
+ rec->arch.ool_stub = (unsigned long)&ool_stub->insn[0];
+
+ /* bl ftrace_caller */
+ if (!mod)
+ ret = ftrace_get_call_inst(rec, (unsigned long)ftrace_caller, &inst);
+#ifdef CONFIG_MODULES
+ else
+ /*
+ * We can't use ftrace_get_call_inst() since that uses
+ * __module_text_address(rec->ip) to look up the module.
+ * But, since the module is not fully formed at this stage,
+ * the lookup fails. We know the target though, so generate
+ * the branch inst directly.
+ */
+ inst = ftrace_create_branch_inst(ftrace_get_ool_stub(rec) + MCOUNT_INSN_SIZE,
+ mod->arch.tramp, 1);
+#endif
+ ool_stub_template.insn[1] = ppc_inst_val(inst);
+
+ /* b rec->ip + 4 */
+ if (!ret && create_branch(&inst, &ool_stub->insn[3], rec->ip + MCOUNT_INSN_SIZE, 0))
+ return -EINVAL;
+ ool_stub_template.insn[3] = ppc_inst_val(inst);
+
+ if (!ret)
+ ret = patch_instructions((u32 *)ool_stub, (u32 *)&ool_stub_template,
+ sizeof(ool_stub_template), false);
+
+ return ret;
+#else /* !CONFIG_PPC_FTRACE_OUT_OF_LINE */
+ BUILD_BUG();
+#endif
+}
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS
+static const struct ftrace_ops *powerpc_rec_get_ops(struct dyn_ftrace *rec)
+{
+ const struct ftrace_ops *ops = NULL;
+
+ if (rec->flags & FTRACE_FL_CALL_OPS_EN) {
+ ops = ftrace_find_unique_ops(rec);
+ WARN_ON_ONCE(!ops);
+ }
+
+ if (!ops)
+ ops = &ftrace_list_ops;
+
+ return ops;
+}
+
+static int ftrace_rec_set_ops(struct dyn_ftrace *rec, const struct ftrace_ops *ops)
+{
+ if (IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE))
+ return patch_ulong((void *)(ftrace_get_ool_stub(rec) - sizeof(unsigned long)),
+ (unsigned long)ops);
+ else
+ return patch_ulong((void *)(rec->ip - MCOUNT_INSN_SIZE - sizeof(unsigned long)),
+ (unsigned long)ops);
+}
+
+static int ftrace_rec_set_nop_ops(struct dyn_ftrace *rec)
+{
+ return ftrace_rec_set_ops(rec, &ftrace_nop_ops);
+}
+
+static int ftrace_rec_update_ops(struct dyn_ftrace *rec)
+{
+ return ftrace_rec_set_ops(rec, powerpc_rec_get_ops(rec));
+}
+#else
+static int ftrace_rec_set_nop_ops(struct dyn_ftrace *rec) { return 0; }
+static int ftrace_rec_update_ops(struct dyn_ftrace *rec) { return 0; }
+#endif
+
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, unsigned long addr)
{
@@ -147,18 +328,33 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, unsigned
int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
{
ppc_inst_t old, new;
- int ret;
+ unsigned long ip = rec->ip;
+ int ret = 0;
/* This can only ever be called during module load */
- if (WARN_ON(!IS_ENABLED(CONFIG_MODULES) || core_kernel_text(rec->ip)))
+ if (WARN_ON(!IS_ENABLED(CONFIG_MODULES) || core_kernel_text(ip)))
return -EINVAL;
old = ppc_inst(PPC_RAW_NOP());
- ret = ftrace_get_call_inst(rec, addr, &new);
+ if (IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE)) {
+ ip = ftrace_get_ool_stub(rec) + MCOUNT_INSN_SIZE; /* second instruction in stub */
+ ret = ftrace_get_call_inst(rec, (unsigned long)ftrace_caller, &old);
+ }
+
+ ret |= ftrace_get_call_inst(rec, addr, &new);
+
+ if (!ret)
+ ret = ftrace_modify_code(ip, old, new);
+
+ ret = ftrace_rec_update_ops(rec);
if (ret)
return ret;
- return ftrace_modify_code(rec->ip, old, new);
+ if (!ret && IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE))
+ ret = ftrace_modify_code(rec->ip, ppc_inst(PPC_RAW_NOP()),
+ ppc_inst(PPC_RAW_BRANCH((long)ftrace_get_ool_stub(rec) - (long)rec->ip)));
+
+ return ret;
}
int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr)
@@ -191,6 +387,13 @@ void ftrace_replace_code(int enable)
new_addr = ftrace_get_addr_new(rec);
update = ftrace_update_record(rec, enable);
+ if (IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE) && update != FTRACE_UPDATE_IGNORE) {
+ ip = ftrace_get_ool_stub(rec) + MCOUNT_INSN_SIZE;
+ ret = ftrace_get_call_inst(rec, (unsigned long)ftrace_caller, &nop_inst);
+ if (ret)
+ goto out;
+ }
+
switch (update) {
case FTRACE_UPDATE_IGNORE:
default:
@@ -198,16 +401,19 @@ void ftrace_replace_code(int enable)
case FTRACE_UPDATE_MODIFY_CALL:
ret = ftrace_get_call_inst(rec, new_addr, &new_call_inst);
ret |= ftrace_get_call_inst(rec, addr, &call_inst);
+ ret |= ftrace_rec_update_ops(rec);
old = call_inst;
new = new_call_inst;
break;
case FTRACE_UPDATE_MAKE_NOP:
ret = ftrace_get_call_inst(rec, addr, &call_inst);
+ ret |= ftrace_rec_set_nop_ops(rec);
old = call_inst;
new = nop_inst;
break;
case FTRACE_UPDATE_MAKE_CALL:
ret = ftrace_get_call_inst(rec, new_addr, &call_inst);
+ ret |= ftrace_rec_update_ops(rec);
old = nop_inst;
new = call_inst;
break;
@@ -215,6 +421,24 @@ void ftrace_replace_code(int enable)
if (!ret)
ret = ftrace_modify_code(ip, old, new);
+
+ if (!ret && IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE) &&
+ (update == FTRACE_UPDATE_MAKE_NOP || update == FTRACE_UPDATE_MAKE_CALL)) {
+ /* Update the actual ftrace location */
+ call_inst = ppc_inst(PPC_RAW_BRANCH((long)ftrace_get_ool_stub(rec) -
+ (long)rec->ip));
+ nop_inst = ppc_inst(PPC_RAW_NOP());
+ ip = rec->ip;
+
+ if (update == FTRACE_UPDATE_MAKE_NOP)
+ ret = ftrace_modify_code(ip, call_inst, nop_inst);
+ else
+ ret = ftrace_modify_code(ip, nop_inst, call_inst);
+
+ if (ret)
+ goto out;
+ }
+
if (ret)
goto out;
}
@@ -234,20 +458,27 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec)
/* Verify instructions surrounding the ftrace location */
if (IS_ENABLED(CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY)) {
/* Expect nops */
- ret = ftrace_validate_inst(ip - 4, ppc_inst(PPC_RAW_NOP()));
+ if (!IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE))
+ ret = ftrace_validate_inst(ip - 4, ppc_inst(PPC_RAW_NOP()));
if (!ret)
ret = ftrace_validate_inst(ip, ppc_inst(PPC_RAW_NOP()));
} else if (IS_ENABLED(CONFIG_PPC32)) {
/* Expected sequence: 'mflr r0', 'stw r0,4(r1)', 'bl _mcount' */
ret = ftrace_validate_inst(ip - 8, ppc_inst(PPC_RAW_MFLR(_R0)));
- if (!ret)
- ret = ftrace_validate_inst(ip - 4, ppc_inst(PPC_RAW_STW(_R0, _R1, 4)));
+ if (ret)
+ return ret;
+ ret = ftrace_modify_code(ip - 4, ppc_inst(PPC_RAW_STW(_R0, _R1, 4)),
+ ppc_inst(PPC_RAW_NOP()));
} else if (IS_ENABLED(CONFIG_MPROFILE_KERNEL)) {
/* Expected sequence: 'mflr r0', ['std r0,16(r1)'], 'bl _mcount' */
ret = ftrace_read_inst(ip - 4, &old);
if (!ret && !ppc_inst_equal(old, ppc_inst(PPC_RAW_MFLR(_R0)))) {
+ /* Gcc v5.x emit the additional 'std' instruction, gcc v6.x don't */
ret = ftrace_validate_inst(ip - 8, ppc_inst(PPC_RAW_MFLR(_R0)));
- ret |= ftrace_validate_inst(ip - 4, ppc_inst(PPC_RAW_STD(_R0, _R1, 16)));
+ if (ret)
+ return ret;
+ ret = ftrace_modify_code(ip - 4, ppc_inst(PPC_RAW_STD(_R0, _R1, 16)),
+ ppc_inst(PPC_RAW_NOP()));
}
} else {
return -EINVAL;
@@ -256,13 +487,9 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec)
if (ret)
return ret;
- if (!core_kernel_text(ip)) {
- if (!mod) {
- pr_err("0x%lx: No module provided for non-kernel address\n", ip);
- return -EFAULT;
- }
- rec->arch.mod = mod;
- }
+ /* Set up out-of-line stub */
+ if (IS_ENABLED(CONFIG_PPC_FTRACE_OUT_OF_LINE))
+ return ftrace_init_ool_stub(mod, rec);
/* Nop-out the ftrace location */
new = ppc_inst(PPC_RAW_NOP());
@@ -302,6 +529,13 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
ppc_inst_t old, new;
int ret;
+ /*
+ * When using CALL_OPS, the function to call is associated with the
+ * call site, and we don't have a global function pointer to update.
+ */
+ if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS))
+ return 0;
+
old = ppc_inst_read((u32 *)&ftrace_call);
new = ftrace_create_branch_inst(ip, ppc_function_entry(func), 1);
ret = ftrace_modify_code(ip, old, new);
@@ -421,8 +655,7 @@ int __init ftrace_dyn_arch_init(void)
void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct ftrace_regs *fregs)
{
- unsigned long sp = fregs->regs.gpr[1];
- int bit;
+ unsigned long sp = arch_ftrace_regs(fregs)->regs.gpr[1];
if (unlikely(ftrace_graph_is_dead()))
goto out;
@@ -430,15 +663,10 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
if (unlikely(atomic_read(&current->tracing_graph_pause)))
goto out;
- bit = ftrace_test_recursion_trylock(ip, parent_ip);
- if (bit < 0)
- goto out;
-
- if (!function_graph_enter(parent_ip, ip, 0, (unsigned long *)sp))
+ if (!function_graph_enter_regs(parent_ip, ip, 0, (unsigned long *)sp, fregs))
parent_ip = ppc_function_entry(return_to_handler);
- ftrace_test_recursion_unlock(bit);
out:
- fregs->regs.link = parent_ip;
+ arch_ftrace_regs(fregs)->regs.link = parent_ip;
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.c b/arch/powerpc/kernel/trace/ftrace_64_pg.c
index 12fab1803bcf..5c6e545d1708 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_pg.c
+++ b/arch/powerpc/kernel/trace/ftrace_64_pg.c
@@ -23,7 +23,7 @@
#include <linux/list.h>
#include <asm/cacheflush.h>
-#include <asm/code-patching.h>
+#include <asm/text-patching.h>
#include <asm/ftrace.h>
#include <asm/syscall.h>
#include <asm/inst.h>
@@ -116,6 +116,18 @@ static unsigned long find_bl_target(unsigned long ip, ppc_inst_t op)
}
#ifdef CONFIG_MODULES
+static struct module *ftrace_lookup_module(struct dyn_ftrace *rec)
+{
+ struct module *mod;
+
+ scoped_guard(rcu)
+ mod = __module_text_address(rec->ip);
+ if (!mod)
+ pr_err("No module loaded at addr=%lx\n", rec->ip);
+
+ return mod;
+}
+
static int
__ftrace_make_nop(struct module *mod,
struct dyn_ftrace *rec, unsigned long addr)
@@ -124,6 +136,12 @@ __ftrace_make_nop(struct module *mod,
unsigned long ip = rec->ip;
ppc_inst_t op, pop;
+ if (!mod) {
+ mod = ftrace_lookup_module(rec);
+ if (!mod)
+ return -EINVAL;
+ }
+
/* read where this goes */
if (copy_inst_from_kernel_nofault(&op, (void *)ip)) {
pr_err("Fetching opcode failed.\n");
@@ -366,27 +384,6 @@ int ftrace_make_nop(struct module *mod,
return -EINVAL;
}
- /*
- * Out of range jumps are called from modules.
- * We should either already have a pointer to the module
- * or it has been passed in.
- */
- if (!rec->arch.mod) {
- if (!mod) {
- pr_err("No module loaded addr=%lx\n", addr);
- return -EFAULT;
- }
- rec->arch.mod = mod;
- } else if (mod) {
- if (mod != rec->arch.mod) {
- pr_err("Record mod %p not equal to passed in mod %p\n",
- rec->arch.mod, mod);
- return -EINVAL;
- }
- /* nothing to do if mod == rec->arch.mod */
- } else
- mod = rec->arch.mod;
-
return __ftrace_make_nop(mod, rec, addr);
}
@@ -411,7 +408,10 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
ppc_inst_t op[2];
void *ip = (void *)rec->ip;
unsigned long entry, ptr, tramp;
- struct module *mod = rec->arch.mod;
+ struct module *mod = ftrace_lookup_module(rec);
+
+ if (!mod)
+ return -EINVAL;
/* read where this goes */
if (copy_inst_from_kernel_nofault(op, ip))
@@ -533,16 +533,6 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
return -EINVAL;
}
- /*
- * Out of range jumps are called from modules.
- * Being that we are converting from nop, it had better
- * already have a module defined.
- */
- if (!rec->arch.mod) {
- pr_err("No module loaded\n");
- return -EINVAL;
- }
-
return __ftrace_make_call(rec, addr);
}
@@ -555,7 +545,10 @@ __ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
ppc_inst_t op;
unsigned long ip = rec->ip;
unsigned long entry, ptr, tramp;
- struct module *mod = rec->arch.mod;
+ struct module *mod = ftrace_lookup_module(rec);
+
+ if (!mod)
+ return -EINVAL;
/* If we never set up ftrace trampolines, then bail */
if (!mod->arch.tramp || !mod->arch.tramp_regs) {
@@ -668,14 +661,6 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
return -EINVAL;
}
- /*
- * 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);
}
#endif
@@ -800,10 +785,10 @@ int ftrace_disable_ftrace_graph_caller(void)
* in current thread info. Return the address we want to divert to.
*/
static unsigned long
-__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp)
+__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp,
+ struct ftrace_regs *fregs)
{
unsigned long return_hooker;
- int bit;
if (unlikely(ftrace_graph_is_dead()))
goto out;
@@ -811,16 +796,11 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp
if (unlikely(atomic_read(&current->tracing_graph_pause)))
goto out;
- bit = ftrace_test_recursion_trylock(ip, parent);
- if (bit < 0)
- goto out;
-
return_hooker = ppc_function_entry(return_to_handler);
- if (!function_graph_enter(parent, ip, 0, (unsigned long *)sp))
+ if (!function_graph_enter_regs(parent, ip, 0, (unsigned long *)sp, fregs))
parent = return_hooker;
- ftrace_test_recursion_unlock(bit);
out:
return parent;
}
@@ -829,13 +809,14 @@ out:
void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct ftrace_regs *fregs)
{
- fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, fregs->regs.gpr[1]);
+ arch_ftrace_regs(fregs)->regs.link = __prepare_ftrace_return(parent_ip, ip,
+ arch_ftrace_regs(fregs)->regs.gpr[1], fregs);
}
#else
unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip,
unsigned long sp)
{
- return __prepare_ftrace_return(parent, ip, sp);
+ return __prepare_ftrace_return(parent, ip, sp, NULL);
}
#endif
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
diff --git a/arch/powerpc/kernel/trace/ftrace_entry.S b/arch/powerpc/kernel/trace/ftrace_entry.S
index 76dbe9fd2c0f..2c1b24100eca 100644
--- a/arch/powerpc/kernel/trace/ftrace_entry.S
+++ b/arch/powerpc/kernel/trace/ftrace_entry.S
@@ -39,13 +39,37 @@
/* Create our stack frame + pt_regs */
PPC_STLU r1,-SWITCH_FRAME_SIZE(r1)
+ .if \allregs == 1
+ SAVE_GPRS(11, 12, r1)
+ .endif
+
+ /* Get the _mcount() call site out of LR */
+ mflr r11
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+ /* Load the ftrace_op */
+ PPC_LL r12, -(MCOUNT_INSN_SIZE*2 + SZL)(r11)
+
+ /* Load direct_call from the ftrace_op */
+ PPC_LL r12, FTRACE_OPS_DIRECT_CALL(r12)
+ PPC_LCMPI r12, 0
+ .if \allregs == 1
+ bne .Lftrace_direct_call_regs
+ .else
+ bne .Lftrace_direct_call
+ .endif
+#endif
+
+ /* Save the previous LR in pt_regs->link */
+ PPC_STL r0, _LINK(r1)
+ /* Also save it in A's stack frame */
+ PPC_STL r0, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE+LRSAVE(r1)
+
/* Save all gprs to pt_regs */
SAVE_GPR(0, r1)
SAVE_GPRS(3, 10, r1)
#ifdef CONFIG_PPC64
- /* Save the original return address in A's stack frame */
- std r0, LRSAVE+SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE(r1)
/* Ok to continue? */
lbz r3, PACA_FTRACE_ENABLED(r13)
cmpdi r3, 0
@@ -54,9 +78,9 @@
.if \allregs == 1
SAVE_GPR(2, r1)
- SAVE_GPRS(11, 31, r1)
+ SAVE_GPRS(13, 31, r1)
.else
-#ifdef CONFIG_LIVEPATCH_64
+#if defined(CONFIG_LIVEPATCH_64) || defined(CONFIG_PPC_FTRACE_OUT_OF_LINE)
SAVE_GPR(14, r1)
#endif
.endif
@@ -67,80 +91,143 @@
.if \allregs == 1
/* Load special regs for save below */
+ mfcr r7
mfmsr r8
mfctr r9
mfxer r10
- mfcr r11
.else
/* Clear MSR to flag as ftrace_caller versus frace_regs_caller */
li r8, 0
.endif
- /* Get the _mcount() call site out of LR */
- mflr r7
- /* Save it as pt_regs->nip */
- PPC_STL r7, _NIP(r1)
- /* Also save it in B's stackframe header for proper unwind */
- PPC_STL r7, LRSAVE+SWITCH_FRAME_SIZE(r1)
- /* Save the read LR in pt_regs->link */
- PPC_STL r0, _LINK(r1)
-
#ifdef CONFIG_PPC64
/* Save callee's TOC in the ABI compliant location */
std r2, STK_GOT(r1)
LOAD_PACA_TOC() /* get kernel TOC in r2 */
+#endif
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS
+ /* r11 points to the instruction following the call to ftrace */
+ PPC_LL r5, -(MCOUNT_INSN_SIZE*2 + SZL)(r11)
+ PPC_LL r12, FTRACE_OPS_FUNC(r5)
+ mtctr r12
+#else /* !CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS */
+#ifdef CONFIG_PPC64
LOAD_REG_ADDR(r3, function_trace_op)
ld r5,0(r3)
#else
lis r3,function_trace_op@ha
lwz r5,function_trace_op@l(r3)
#endif
-
-#ifdef CONFIG_LIVEPATCH_64
- mr r14, r7 /* remember old NIP */
#endif
- /* 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
-
/* Save special regs */
PPC_STL r8, _MSR(r1)
.if \allregs == 1
+ PPC_STL r7, _CCR(r1)
PPC_STL r9, _CTR(r1)
PPC_STL r10, _XER(r1)
- PPC_STL r11, _CCR(r1)
.endif
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+ /* Clear orig_gpr3 to later detect ftrace_direct call */
+ li r7, 0
+ PPC_STL r7, ORIG_GPR3(r1)
+#endif
+
+#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
+ /* Save our real return address in nvr for return */
+ .if \allregs == 0
+ SAVE_GPR(15, r1)
+ .endif
+ mr r15, r11
+ /*
+ * We want the ftrace location in the function, but our lr (in r11)
+ * points at the 'mtlr r0' instruction in the out of line stub. To
+ * recover the ftrace location, we read the branch instruction in the
+ * stub, and adjust our lr by the branch offset.
+ *
+ * See ftrace_init_ool_stub() for the profile sequence.
+ */
+ lwz r8, MCOUNT_INSN_SIZE(r11)
+ slwi r8, r8, 6
+ srawi r8, r8, 6
+ add r3, r11, r8
+ /*
+ * Override our nip to point past the branch in the original function.
+ * This allows reliable stack trace and the ftrace stack tracer to work as-is.
+ */
+ addi r11, r3, MCOUNT_INSN_SIZE
+#else
+ /* Calculate ip from nip-4 into r3 for call below */
+ subi r3, r11, MCOUNT_INSN_SIZE
+#endif
+
+ /* Save NIP as pt_regs->nip */
+ PPC_STL r11, _NIP(r1)
+ /* Also save it in B's stackframe header for proper unwind */
+ PPC_STL r11, LRSAVE+SWITCH_FRAME_SIZE(r1)
+#if defined(CONFIG_LIVEPATCH_64) || defined(CONFIG_PPC_FTRACE_OUT_OF_LINE)
+ mr r14, r11 /* remember old NIP */
+#endif
+
+ /* Put the original return address in r4 as parent_ip */
+ mr r4, r0
+
/* Load &pt_regs in r6 for call below */
addi r6, r1, STACK_INT_FRAME_REGS
.endm
.macro ftrace_regs_exit allregs
- /* Load ctr with the possibly modified NIP */
- PPC_LL r3, _NIP(r1)
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+ /* Check orig_gpr3 to detect ftrace_direct call */
+ PPC_LL r3, ORIG_GPR3(r1)
+ PPC_LCMPI cr1, r3, 0
mtctr r3
+#endif
+ /* Restore possibly modified LR */
+ PPC_LL r0, _LINK(r1)
+
+#ifndef CONFIG_PPC_FTRACE_OUT_OF_LINE
+ /* Load ctr with the possibly modified NIP */
+ PPC_LL r3, _NIP(r1)
#ifdef CONFIG_LIVEPATCH_64
cmpd r14, r3 /* has NIP been altered? */
#endif
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+ beq cr1,2f
+ mtlr r3
+ b 3f
+#endif
+2: mtctr r3
+ mtlr r0
+3:
+
+#else /* !CONFIG_PPC_FTRACE_OUT_OF_LINE */
+ /* Load LR with the possibly modified NIP */
+ PPC_LL r3, _NIP(r1)
+ cmpd r14, r3 /* has NIP been altered? */
+ bne- 1f
+
+ mr r3, r15
+ .if \allregs == 0
+ REST_GPR(15, r1)
+ .endif
+1: mtlr r3
+#endif
+
/* Restore gprs */
.if \allregs == 1
REST_GPRS(2, 31, r1)
.else
REST_GPRS(3, 10, r1)
-#ifdef CONFIG_LIVEPATCH_64
+#if defined(CONFIG_LIVEPATCH_64) || defined(CONFIG_PPC_FTRACE_OUT_OF_LINE)
REST_GPR(14, r1)
#endif
.endif
- /* Restore possibly modified LR */
- PPC_LL r0, _LINK(r1)
- mtlr r0
-
#ifdef CONFIG_PPC64
/* Restore callee's TOC */
ld r2, STK_GOT(r1)
@@ -153,23 +240,46 @@
/* Based on the cmpd above, if the NIP was altered handle livepatch */
bne- livepatch_handler
#endif
- bctr /* jump after _mcount site */
+
+ /* jump after _mcount site */
+#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+ bnectr cr1
+#endif
+ /*
+ * Return with blr to keep the link stack balanced. The function profiling sequence
+ * uses 'mtlr r0' to restore LR.
+ */
+ blr
+#else
+ bctr
+#endif
.endm
-_GLOBAL(ftrace_regs_caller)
- ftrace_regs_entry 1
- /* ftrace_call(r3, r4, r5, r6) */
+.macro ftrace_regs_func allregs
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS
+ bctrl
+#else
+ .if \allregs == 1
.globl ftrace_regs_call
ftrace_regs_call:
+ .else
+.globl ftrace_call
+ftrace_call:
+ .endif
+ /* ftrace_call(r3, r4, r5, r6) */
bl ftrace_stub
+#endif
+.endm
+
+_GLOBAL(ftrace_regs_caller)
+ ftrace_regs_entry 1
+ ftrace_regs_func 1
ftrace_regs_exit 1
_GLOBAL(ftrace_caller)
ftrace_regs_entry 0
- /* ftrace_call(r3, r4, r5, r6) */
-.globl ftrace_call
-ftrace_call:
- bl ftrace_stub
+ ftrace_regs_func 0
ftrace_regs_exit 0
_GLOBAL(ftrace_stub)
@@ -177,6 +287,11 @@ _GLOBAL(ftrace_stub)
#ifdef CONFIG_PPC64
ftrace_no_trace:
+#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
+ REST_GPR(3, r1)
+ addi r1, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE
+ blr
+#else
mflr r3
mtctr r3
REST_GPR(3, r1)
@@ -184,6 +299,22 @@ ftrace_no_trace:
mtlr r0
bctr
#endif
+#endif
+
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+.Lftrace_direct_call_regs:
+ mtctr r12
+ REST_GPRS(11, 12, r1)
+ addi r1, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE
+ bctr
+.Lftrace_direct_call:
+ mtctr r12
+ addi r1, r1, SWITCH_FRAME_SIZE+STACK_FRAME_MIN_SIZE
+ bctr
+SYM_FUNC_START(ftrace_stub_direct_tramp)
+ blr
+SYM_FUNC_END(ftrace_stub_direct_tramp)
+#endif
#ifdef CONFIG_LIVEPATCH_64
/*
@@ -194,11 +325,17 @@ ftrace_no_trace:
* We get here when a function A, calls another function B, but B has
* been live patched with a new function C.
*
- * On entry:
- * - we have no stack frame and can not allocate one
+ * On entry, we have no stack frame and can not allocate one.
+ *
+ * With PPC_FTRACE_OUT_OF_LINE=n, on entry:
* - LR points back to the original caller (in A)
* - CTR holds the new NIP in C
* - r0, r11 & r12 are free
+ *
+ * With PPC_FTRACE_OUT_OF_LINE=y, on entry:
+ * - r0 points back to the original caller (in A)
+ * - LR holds the new NIP in C
+ * - r11 & r12 are free
*/
livepatch_handler:
ld r12, PACA_THREAD_INFO(r13)
@@ -208,18 +345,23 @@ livepatch_handler:
addi r11, r11, 24
std r11, TI_livepatch_sp(r12)
- /* Save toc & real LR on livepatch stack */
- std r2, -24(r11)
- mflr r12
- std r12, -16(r11)
-
/* Store stack end marker */
lis r12, STACK_END_MAGIC@h
ori r12, r12, STACK_END_MAGIC@l
std r12, -8(r11)
- /* Put ctr in r12 for global entry and branch there */
+ /* Save toc & real LR on livepatch stack */
+ std r2, -24(r11)
+#ifndef CONFIG_PPC_FTRACE_OUT_OF_LINE
+ mflr r12
+ std r12, -16(r11)
mfctr r12
+#else
+ std r0, -16(r11)
+ mflr r12
+ /* Put ctr in r12 for global entry and branch there */
+ mtctr r12
+#endif
bctrl
/*
@@ -308,6 +450,14 @@ _GLOBAL(return_to_handler)
blr
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE
+SYM_DATA(ftrace_ool_stub_text_count, .long CONFIG_PPC_FTRACE_OUT_OF_LINE_NUM_RESERVE)
+
+SYM_START(ftrace_ool_stub_text, SYM_L_GLOBAL, .balign SZL)
+ .space CONFIG_PPC_FTRACE_OUT_OF_LINE_NUM_RESERVE * FTRACE_OOL_STUB_SIZE
+SYM_CODE_END(ftrace_ool_stub_text)
+#endif
+
.pushsection ".tramp.ftrace.text","aw",@progbits;
.globl ftrace_tramp_text
ftrace_tramp_text: