diff mbox series

[v3,2/9] powerpc/traps: Return early in show_signal_msg()

Message ID 20180731145020.14009-3-muriloo@linux.ibm.com (mailing list archive)
State Superseded, archived
Headers show
Series powerpc: Modernize unhandled signals message | expand

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Commit Message

Murilo Opsfelder Araújo July 31, 2018, 2:50 p.m. UTC 
Modify the logic of show_signal_msg() to return early, if possible.
Replace printk_ratelimited() by printk() and a default rate limit burst to
limit displaying unhandled signals messages.

Mainly reason of this change is to improve readability of the function.
The conditions to display the message were coupled together in one single
`if` statement.

Splitting out the rate limit check outside show_signal_msg() makes it
easier to the caller decide if it wants to respect a printk rate limit or
not.

Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
---
 arch/powerpc/kernel/traps.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index cbd3dc365193..4faab4705774 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -301,6 +301,13 @@  void user_single_step_siginfo(struct task_struct *tsk,
 	info->si_addr = (void __user *)regs->nip;
 }
 
+static bool show_unhandled_signals_ratelimited(void)
+{
+	static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
+				      DEFAULT_RATELIMIT_BURST);
+	return show_unhandled_signals && __ratelimit(&rs);
+}
+
 static void show_signal_msg(int signr, struct pt_regs *regs, int code,
 			    unsigned long addr)
 {
@@ -309,11 +316,12 @@  static void show_signal_msg(int signr, struct pt_regs *regs, int code,
 	const char fmt64[] = KERN_INFO "%s[%d]: unhandled signal %d " \
 		"at %016lx nip %016lx lr %016lx code %x\n";
 
-	if (show_unhandled_signals && unhandled_signal(current, signr)) {
-		printk_ratelimited(regs->msr & MSR_64BIT ? fmt64 : fmt32,
-				   current->comm, current->pid, signr,
-				   addr, regs->nip, regs->link, code);
-	}
+	if (!unhandled_signal(current, signr))
+		return;
+
+	printk(regs->msr & MSR_64BIT ? fmt64 : fmt32,
+	       current->comm, current->pid, signr,
+	       addr, regs->nip, regs->link, code);
 }
 
 void _exception_pkey(int signr, struct pt_regs *regs, int code,
@@ -326,7 +334,8 @@  void _exception_pkey(int signr, struct pt_regs *regs, int code,
 		return;
 	}
 
-	show_signal_msg(signr, regs, code, addr);
+	if (show_unhandled_signals_ratelimited())
+		show_signal_msg(signr, regs, code, addr);
 
 	if (arch_irqs_disabled() && !arch_irq_disabled_regs(regs))
 		local_irq_enable();