From: Hosung Kim <hosung0.kim@samsung.com>
Date: Fri, 12 Jun 2015 13:40:21 +0000 (+0900)
Subject: [COMMON] printk: add supporting core number and process information
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=3d28310a6c4b80606fa72ee49e4d5bbb09683eda;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

[COMMON] printk: add supporting core number and process information

This commit adds supporting to output the core number and process
information. They are depending on as following configuration.
- CONFIG_PRINTK_PROCESS

Change-Id: I09698dc00e5acd1bb11b9a564fdc3f129c04b642
Signed-off-by: Hosung Kim <hosung0.kim@samsung.com>
Signed-off-by: Hyunki Koo <hyunki00.koo@samsung.com>
---

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 512f7c2baedd..c911f8f7fa2d 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -359,6 +359,12 @@ struct printk_log {
 	u8 facility;		/* syslog facility */
 	u8 flags:5;		/* internal record flags */
 	u8 level:3;		/* syslog level */
+#ifdef CONFIG_PRINTK_PROCESS
+	char process[16];	/* process name */
+	pid_t pid;		/* process id */
+	u8 cpu;			/* cpu id */
+	u8 in_interrupt;	/* interrupt context */
+#endif
 }
 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
 __packed __aligned(4)
@@ -423,7 +429,11 @@ static u32 console_idx;
 static u64 clear_seq;
 static u32 clear_idx;
 
+#ifdef CONFIG_PRINTK_PROCESS
+#define PREFIX_MAX		48
+#else
 #define PREFIX_MAX		32
+#endif
 #define LOG_LINE_MAX		(1024 - PREFIX_MAX)
 
 #define LOG_LEVEL(v)		((v) & 0x07)
@@ -550,6 +560,32 @@ static u32 msg_used_size(u16 text_len, u16 dict_len, u32 *pad_len)
 	return size;
 }
 
+#ifdef CONFIG_PRINTK_PROCESS
+static bool printk_process = 1;
+static size_t print_process(const struct printk_log *msg, char *buf)
+
+{
+	if (!printk_process)
+		return 0;
+
+	if (!buf)
+		return snprintf(NULL, 0, "%c[%1d:%15s:%5d] ", ' ', 0, " ", 0);
+
+	return sprintf(buf, "%c[%1d:%15s:%5d] ",
+			msg->in_interrupt ? 'I' : ' ',
+			msg->cpu,
+			msg->process,
+			msg->pid);
+}
+#else
+static bool printk_process = 0;
+static size_t print_process(const struct printk_log *msg, char *buf)
+{
+	return 0;
+}
+#endif
+module_param_named(process, printk_process, bool, S_IRUGO | S_IWUSR);
+
 /*
  * Define how much of the log buffer we could take at maximum. The value
  * must be greater than two. Note that only half of the buffer is available
@@ -628,6 +664,15 @@ static int log_store(int facility, int level,
 	memset(log_dict(msg) + dict_len, 0, pad_len);
 	msg->len = size;
 
+#ifdef CONFIG_PRINTK_PROCESS
+	if (printk_process) {
+		strncpy(msg->process, current->comm, sizeof(msg->process) - 1);
+		msg->process[sizeof(msg->process) - 1] = '\0';
+		msg->pid = task_pid_nr(current);
+		msg->cpu = smp_processor_id();
+		msg->in_interrupt = in_interrupt() ? 1 : 0;
+	}
+#endif
 	/* insert message */
 	log_next_idx += msg->len;
 	log_next_seq++;
@@ -1240,6 +1285,7 @@ static size_t print_prefix(const struct printk_log *msg, bool syslog, char *buf)
 	}
 
 	len += print_time(msg->ts_nsec, buf ? buf + len : NULL);
+	len += print_process(msg, buf ? buf + len : NULL);
 	return len;
 }
 
@@ -1689,6 +1735,7 @@ asmlinkage int vprintk_emit(int facility, int level,
 	size_t text_len;
 	enum log_flags lflags = 0;
 	unsigned long flags;
+	int this_cpu;
 	int printed_len;
 	bool in_sched = false;
 
@@ -1702,6 +1749,7 @@ asmlinkage int vprintk_emit(int facility, int level,
 
 	/* This stops the holder of console_sem just where we want him */
 	logbuf_lock_irqsave(flags);
+	this_cpu = smp_processor_id();
 	/*
 	 * The printf needs to come first; we need the syslog
 	 * prefix which might be passed-in as a parameter.
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 62d0e25c054c..fc3c8906d2be 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -30,6 +30,13 @@ config CONSOLE_LOGLEVEL_DEFAULT
 	  usage in the kernel. That is controlled by the MESSAGE_LOGLEVEL_DEFAULT
 	  option.
 
+config PRINTK_PROCESS
+	bool "Show process information on printks"
+	depends on PRINTK
+	help
+	  Selecting this option causes process to be
+	  included in printk output. Or add printk.process=1 at boot-time.
+
 config MESSAGE_LOGLEVEL_DEFAULT
 	int "Default message log level (1-7)"
 	range 1 7