diff mbox series

[083/118] proc/wchan: use printk format instead of lookup_symbol_name()

Message ID 20210226012045.H_Iz_JaD3%akpm@linux-foundation.org (mailing list archive)
State New
Headers show
Series [001/118] mm: make pagecache tagged lookups return only head pages | expand

Commit Message

Andrew Morton Feb. 26, 2021, 1:20 a.m. UTC
From: Helge Deller <deller@gmx.de>
Subject: proc/wchan: use printk format instead of lookup_symbol_name()

To resolve the symbol fuction name for wchan, use the printk format
specifier %ps instead of manually looking up the symbol function name
via lookup_symbol_name().

Link: https://lkml.kernel.org/r/20201217165413.GA1959@ls3530.fritz.box
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/proc/base.c |   21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)
diff mbox series

Patch

--- a/fs/proc/base.c~proc-wchan-use-printk-format-instead-of-lookup_symbol_name
+++ a/fs/proc/base.c
@@ -67,7 +67,6 @@ 
 #include <linux/mm.h>
 #include <linux/swap.h>
 #include <linux/rcupdate.h>
-#include <linux/kallsyms.h>
 #include <linux/stacktrace.h>
 #include <linux/resource.h>
 #include <linux/module.h>
@@ -386,19 +385,17 @@  static int proc_pid_wchan(struct seq_fil
 			  struct pid *pid, struct task_struct *task)
 {
 	unsigned long wchan;
-	char symname[KSYM_NAME_LEN];
 
-	if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
-		goto print0;
+	if (ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
+		wchan = get_wchan(task);
+	else
+		wchan = 0;
+
+	if (wchan)
+		seq_printf(m, "%ps", (void *) wchan);
+	else
+		seq_putc(m, '0');
 
-	wchan = get_wchan(task);
-	if (wchan && !lookup_symbol_name(wchan, symname)) {
-		seq_puts(m, symname);
-		return 0;
-	}
-
-print0:
-	seq_putc(m, '0');
 	return 0;
 }
 #endif /* CONFIG_KALLSYMS */