From 92550405c493a3c2fa14bf37d1d60cd6c7d0f585 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Tue, 25 Feb 2014 21:33:59 -0500 Subject: [PATCH] ftrace/x86: Have ftrace_write() return -EPERM and clean up callers Having ftrace_write() return -EPERM on failure, as that's what the callers return, then we can clean up the code a bit. That is, instead of: if (ftrace_write(...)) return -EPERM; return 0; or if (ftrace_write(...)) { ret = -EPERM; goto_out; } We can instead have: return ftrace_write(...); or ret = ftrace_write(...); if (ret) goto out; Signed-off-by: Steven Rostedt --- arch/x86/kernel/ftrace.c | 27 ++++++++------------------- 1 file changed, 8 insertions(+), 19 deletions(-) diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 69885e2f2095..8cabf638cb63 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -308,7 +308,10 @@ static int ftrace_write(unsigned long ip, const char *val, int size) if (within(ip, (unsigned long)_text, (unsigned long)_etext)) ip = (unsigned long)__va(__pa_symbol(ip)); - return probe_kernel_write((void *)ip, val, size); + if (probe_kernel_write((void *)ip, val, size)) + return -EPERM; + + return 0; } static int add_break(unsigned long ip, const char *old) @@ -323,10 +326,7 @@ static int add_break(unsigned long ip, const char *old) if (memcmp(replaced, old, MCOUNT_INSN_SIZE) != 0) return -EINVAL; - if (ftrace_write(ip, &brk, 1)) - return -EPERM; - - return 0; + return ftrace_write(ip, &brk, 1); } static int add_brk_on_call(struct dyn_ftrace *rec, unsigned long addr) @@ -463,9 +463,7 @@ static int add_update_code(unsigned long ip, unsigned const char *new) /* skip breakpoint */ ip++; new++; - if (ftrace_write(ip, new, MCOUNT_INSN_SIZE - 1)) - return -EPERM; - return 0; + return ftrace_write(ip, new, MCOUNT_INSN_SIZE - 1); } static int add_update_call(struct dyn_ftrace *rec, unsigned long addr) @@ -520,10 +518,7 @@ static int finish_update_call(struct dyn_ftrace *rec, unsigned long addr) new = ftrace_call_replace(ip, addr); - if (ftrace_write(ip, new, 1)) - return -EPERM; - - return 0; + return ftrace_write(ip, new, 1); } static int finish_update_nop(struct dyn_ftrace *rec) @@ -533,9 +528,7 @@ static int finish_update_nop(struct dyn_ftrace *rec) new = ftrace_nop_replace(); - if (ftrace_write(ip, new, 1)) - return -EPERM; - return 0; + return ftrace_write(ip, new, 1); } static int finish_update(struct dyn_ftrace *rec, int enable) @@ -656,10 +649,6 @@ ftrace_modify_code(unsigned long ip, unsigned const char *old_code, run_sync(); ret = ftrace_write(ip, new_code, 1); - if (ret) { - ret = -EPERM; - goto out; - } out: run_sync(); return ret; -- 2.11.0