From: Huang, Tao <huangtao@rock-chips.com>
Date: Tue, 2 Jun 2015 11:09:35 +0000 (+0800)
Subject: add support show process information on printks
X-Git-Tag: firefly_0821_release~4081
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ceaeb4796f73c5d8f180b5cf942e62448ea7209f;p=firefly-linux-kernel-4.4.55.git

add support show process information on printks

Signed-off-by: Huang, Tao <huangtao@rock-chips.com>
---

diff --git a/kernel/printk.c b/kernel/printk.c
index 7d9dc9ad97f6..7c36e3eb7a54 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -212,6 +212,12 @@ struct 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
 };
 
 /*
@@ -245,7 +251,11 @@ static enum log_flags console_prev;
 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
 
 /* record buffer */
@@ -306,6 +316,25 @@ static u32 log_next(u32 idx)
 	return idx + msg->len;
 }
 
+#ifdef CONFIG_PRINTK_PROCESS
+static bool printk_process = 1;
+static size_t print_process(const struct 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);
+}
+module_param_named(process, printk_process, bool, S_IRUGO | S_IWUSR);
+#endif
+
 #ifdef CONFIG_RK_LAST_LOG
 extern void rk_last_log_text(char *text, size_t size);
 static char rk_text[1024];
@@ -368,6 +397,16 @@ static void log_store(int facility, int level,
 	memset(log_dict(msg) + dict_len, 0, pad_len);
 	msg->len = sizeof(struct log) + text_len + dict_len + pad_len;
 
+#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
+
 #ifdef CONFIG_RK_LAST_LOG
 	size = msg_print_text(msg, msg->flags, true, rk_text, sizeof(rk_text));
 	rk_last_log_text(rk_text, size);
@@ -918,6 +957,9 @@ static size_t print_prefix(const struct log *msg, bool syslog, char *buf)
 	}
 
 	len += print_time(msg->ts_nsec, buf ? buf + len : NULL);
+#ifdef CONFIG_PRINTK_PROCESS
+	len += print_process(msg, buf ? buf + len : NULL);
+#endif
 	return len;
 }
 
@@ -1486,6 +1528,10 @@ static size_t cont_print_text(char *text, size_t size)
 
 	if (cont.cons == 0 && (console_prev & LOG_NEWLINE)) {
 		textlen += print_time(cont.ts_nsec, text);
+#ifdef CONFIG_PRINTK_PROCESS
+		*(text+textlen) = ' ';
+		textlen += print_process(NULL, NULL);
+#endif
 		size -= textlen;
 	}
 
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index d317c1ad62ab..d3c6363076ef 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -14,6 +14,13 @@ config PRINTK_TIME
 	  The behavior is also controlled by the kernel command line
 	  parameter printk.time=1. See Documentation/kernel-parameters.txt
 
+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 DEFAULT_MESSAGE_LOGLEVEL
 	int "Default message log level (1-7)"
 	range 1 7