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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/sparc/kernel/ftrace.c | |
parent | Initial commit. (diff) | |
download | linux-upstream/4.19.249.tar.xz linux-upstream/4.19.249.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | arch/sparc/kernel/ftrace.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/sparc/kernel/ftrace.c b/arch/sparc/kernel/ftrace.c new file mode 100644 index 000000000..684b84ce3 --- /dev/null +++ b/arch/sparc/kernel/ftrace.c @@ -0,0 +1,138 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/spinlock.h> +#include <linux/hardirq.h> +#include <linux/ftrace.h> +#include <linux/percpu.h> +#include <linux/init.h> +#include <linux/list.h> +#include <trace/syscall.h> + +#include <asm/ftrace.h> + +#ifdef CONFIG_DYNAMIC_FTRACE +static const u32 ftrace_nop = 0x01000000; + +static u32 ftrace_call_replace(unsigned long ip, unsigned long addr) +{ + u32 call; + s32 off; + + off = ((s32)addr - (s32)ip); + call = 0x40000000 | ((u32)off >> 2); + + return call; +} + +static int ftrace_modify_code(unsigned long ip, u32 old, u32 new) +{ + u32 replaced; + int faulted; + + __asm__ __volatile__( + "1: cas [%[ip]], %[old], %[new]\n" + " flush %[ip]\n" + " mov 0, %[faulted]\n" + "2:\n" + " .section .fixup,#alloc,#execinstr\n" + " .align 4\n" + "3: sethi %%hi(2b), %[faulted]\n" + " jmpl %[faulted] + %%lo(2b), %%g0\n" + " mov 1, %[faulted]\n" + " .previous\n" + " .section __ex_table,\"a\"\n" + " .align 4\n" + " .word 1b, 3b\n" + " .previous\n" + : "=r" (replaced), [faulted] "=r" (faulted) + : [new] "0" (new), [old] "r" (old), [ip] "r" (ip) + : "memory"); + + if (replaced != old && replaced != new) + faulted = 2; + + return faulted; +} + +int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr) +{ + unsigned long ip = rec->ip; + u32 old, new; + + old = ftrace_call_replace(ip, addr); + new = ftrace_nop; + return ftrace_modify_code(ip, old, new); +} + +int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) +{ + unsigned long ip = rec->ip; + u32 old, new; + + old = ftrace_nop; + new = ftrace_call_replace(ip, addr); + return ftrace_modify_code(ip, old, new); +} + +int ftrace_update_ftrace_func(ftrace_func_t func) +{ + unsigned long ip = (unsigned long)(&ftrace_call); + u32 old, new; + + old = *(u32 *) &ftrace_call; + new = ftrace_call_replace(ip, (unsigned long)func); + return ftrace_modify_code(ip, old, new); +} + +int __init ftrace_dyn_arch_init(void) +{ + return 0; +} +#endif + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + +#ifdef CONFIG_DYNAMIC_FTRACE +extern void ftrace_graph_call(void); + +int ftrace_enable_ftrace_graph_caller(void) +{ + unsigned long ip = (unsigned long)(&ftrace_graph_call); + u32 old, new; + + old = *(u32 *) &ftrace_graph_call; + new = ftrace_call_replace(ip, (unsigned long) &ftrace_graph_caller); + return ftrace_modify_code(ip, old, new); +} + +int ftrace_disable_ftrace_graph_caller(void) +{ + unsigned long ip = (unsigned long)(&ftrace_graph_call); + u32 old, new; + + old = *(u32 *) &ftrace_graph_call; + new = ftrace_call_replace(ip, (unsigned long) &ftrace_stub); + + return ftrace_modify_code(ip, old, new); +} + +#endif /* !CONFIG_DYNAMIC_FTRACE */ + +/* + * Hook the return address and push it in the stack of return addrs + * in current thread info. + */ +unsigned long prepare_ftrace_return(unsigned long parent, + unsigned long self_addr, + unsigned long frame_pointer) +{ + unsigned long return_hooker = (unsigned long) &return_to_handler; + + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return parent + 8UL; + + if (function_graph_enter(parent, self_addr, frame_pointer, NULL)) + return parent + 8UL; + + return return_hooker; +} +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |