Re: [RFC v2 1/9] printk: move code regarding log message storing format

[Paul Osmialowski]

Hi Joe,

Thanks for your comment. I'll consider that.

Thanks,
Paul

On Mon, 12 Oct 2015, Joe Perches wrote:


On Mon, 2015-10-12 at 11:29 +0200, Paul Osmialowski wrote:

From: Marcin Niesluchowski 

Preparation commit for future changes purpose.

Moves some code responsible for storing log messages in proper format.


Perhaps better still would be to move the code into
a separate file to reduce the bulk and complexity
of printk.c



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Re: [RFC v2 1/9] printk: move code regarding log message storing format

[Paul Osmialowski]

Hi Joe,

Thanks for your comment. I'll consider that.

Thanks,
Paul

On Mon, 12 Oct 2015, Joe Perches wrote:


On Mon, 2015-10-12 at 11:29 +0200, Paul Osmialowski wrote:

From: Marcin Niesluchowski 

Preparation commit for future changes purpose.

Moves some code responsible for storing log messages in proper format.


Perhaps better still would be to move the code into
a separate file to reduce the bulk and complexity
of printk.c



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Re: [RFC v2 1/9] printk: move code regarding log message storing format

[Joe Perches]

On Mon, 2015-10-12 at 11:29 +0200, Paul Osmialowski wrote:
> From: Marcin Niesluchowski 
> 
> Preparation commit for future changes purpose.
> 
> Moves some code responsible for storing log messages in proper format.

Perhaps better still would be to move the code into
a separate file to reduce the bulk and complexity
of printk.c

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To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
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[RFC v2 1/9] printk: move code regarding log message storing format

[Paul Osmialowski]

From: Marcin Niesluchowski 

Preparation commit for future changes purpose.

Moves some code responsible for storing log messages in proper format.

Signed-off-by: Marcin Niesluchowski 
---
 kernel/printk/printk.c | 254 -
 1 file changed, 127 insertions(+), 127 deletions(-)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 8f0324e..d209072 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -475,6 +475,133 @@ static int log_store(int facility, int level,
return msg->text_len;
 }
 
+static bool printk_time = IS_ENABLED(CONFIG_PRINTK_TIME);
+module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR);
+
+static size_t print_time(u64 ts, char *buf)
+{
+   unsigned long rem_nsec;
+
+   if (!printk_time)
+   return 0;
+
+   rem_nsec = do_div(ts, 10);
+
+   if (!buf)
+   return snprintf(NULL, 0, "[%5lu.00] ", (unsigned long)ts);
+
+   return sprintf(buf, "[%5lu.%06lu] ",
+  (unsigned long)ts, rem_nsec / 1000);
+}
+
+/*
+ * Continuation lines are buffered, and not committed to the record buffer
+ * until the line is complete, or a race forces it. The line fragments
+ * though, are printed immediately to the consoles to ensure everything has
+ * reached the console in case of a kernel crash.
+ */
+static struct cont {
+   char buf[LOG_LINE_MAX];
+   size_t len; /* length == 0 means unused buffer */
+   size_t cons;/* bytes written to console */
+   struct task_struct *owner;  /* task of first print*/
+   u64 ts_nsec;/* time of first print */
+   u8 level;   /* log level of first message */
+   u8 facility;/* log facility of first message */
+   enum log_flags flags;   /* prefix, newline flags */
+   bool flushed:1; /* buffer sealed and committed */
+} cont;
+
+static void cont_flush(enum log_flags flags)
+{
+   if (cont.flushed)
+   return;
+   if (cont.len == 0)
+   return;
+
+   if (cont.cons) {
+   /*
+* If a fragment of this line was directly flushed to the
+* console; wait for the console to pick up the rest of the
+* line. LOG_NOCONS suppresses a duplicated output.
+*/
+   log_store(cont.facility, cont.level, flags | LOG_NOCONS,
+ cont.ts_nsec, NULL, 0, cont.buf, cont.len);
+   cont.flags = flags;
+   cont.flushed = true;
+   } else {
+   /*
+* If no fragment of this line ever reached the console,
+* just submit it to the store and free the buffer.
+*/
+   log_store(cont.facility, cont.level, flags, 0,
+ NULL, 0, cont.buf, cont.len);
+   cont.len = 0;
+   }
+}
+
+static bool cont_add(int facility, int level, const char *text, size_t len)
+{
+   if (cont.len && cont.flushed)
+   return false;
+
+   /*
+* If ext consoles are present, flush and skip in-kernel
+* continuation.  See nr_ext_console_drivers definition.  Also, if
+* the line gets too long, split it up in separate records.
+*/
+   if (nr_ext_console_drivers || cont.len + len > sizeof(cont.buf)) {
+   cont_flush(LOG_CONT);
+   return false;
+   }
+
+   if (!cont.len) {
+   cont.facility = facility;
+   cont.level = level;
+   cont.owner = current;
+   cont.ts_nsec = local_clock();
+   cont.flags = 0;
+   cont.cons = 0;
+   cont.flushed = false;
+   }
+
+   memcpy(cont.buf + cont.len, text, len);
+   cont.len += len;
+
+   if (cont.len > (sizeof(cont.buf) * 80) / 100)
+   cont_flush(LOG_CONT);
+
+   return true;
+}
+
+static size_t cont_print_text(char *text, size_t size)
+{
+   size_t textlen = 0;
+   size_t len;
+
+   if (cont.cons == 0 && (console_prev & LOG_NEWLINE)) {
+   textlen += print_time(cont.ts_nsec, text);
+   size -= textlen;
+   }
+
+   len = cont.len - cont.cons;
+   if (len > 0) {
+   if (len+1 > size)
+   len = size-1;
+   memcpy(text + textlen, cont.buf + cont.cons, len);
+   textlen += len;
+   cont.cons = cont.len;
+   }
+
+   if (cont.flushed) {
+   if (cont.flags & LOG_NEWLINE)
+   text[textlen++] = '\n';
+   /* got everything, release buffer */
+   cont.len = 0;
+   }
+   return textlen;
+}
+
 int dmesg_restrict = IS_ENABLED(CONFIG_SECURITY_DMESG_RESTRICT);
 
 static int syslog_action_restricted(int type)
@@ -1030,25 +1157,6 @@ static 

[RFC v2 1/9] printk: move code regarding log message storing format

[Paul Osmialowski]

From: Marcin Niesluchowski 

Preparation commit for future changes purpose.

Moves some code responsible for storing log messages in proper format.

Signed-off-by: Marcin Niesluchowski 
---
 kernel/printk/printk.c | 254 -
 1 file changed, 127 insertions(+), 127 deletions(-)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 8f0324e..d209072 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -475,6 +475,133 @@ static int log_store(int facility, int level,
return msg->text_len;
 }
 
+static bool printk_time = IS_ENABLED(CONFIG_PRINTK_TIME);
+module_param_named(time, printk_time, bool, S_IRUGO | S_IWUSR);
+
+static size_t print_time(u64 ts, char *buf)
+{
+   unsigned long rem_nsec;
+
+   if (!printk_time)
+   return 0;
+
+   rem_nsec = do_div(ts, 10);
+
+   if (!buf)
+   return snprintf(NULL, 0, "[%5lu.00] ", (unsigned long)ts);
+
+   return sprintf(buf, "[%5lu.%06lu] ",
+  (unsigned long)ts, rem_nsec / 1000);
+}
+
+/*
+ * Continuation lines are buffered, and not committed to the record buffer
+ * until the line is complete, or a race forces it. The line fragments
+ * though, are printed immediately to the consoles to ensure everything has
+ * reached the console in case of a kernel crash.
+ */
+static struct cont {
+   char buf[LOG_LINE_MAX];
+   size_t len; /* length == 0 means unused buffer */
+   size_t cons;/* bytes written to console */
+   struct task_struct *owner;  /* task of first print*/
+   u64 ts_nsec;/* time of first print */
+   u8 level;   /* log level of first message */
+   u8 facility;/* log facility of first message */
+   enum log_flags flags;   /* prefix, newline flags */
+   bool flushed:1; /* buffer sealed and committed */
+} cont;
+
+static void cont_flush(enum log_flags flags)
+{
+   if (cont.flushed)
+   return;
+   if (cont.len == 0)
+   return;
+
+   if (cont.cons) {
+   /*
+* If a fragment of this line was directly flushed to the
+* console; wait for the console to pick up the rest of the
+* line. LOG_NOCONS suppresses a duplicated output.
+*/
+   log_store(cont.facility, cont.level, flags | LOG_NOCONS,
+ cont.ts_nsec, NULL, 0, cont.buf, cont.len);
+   cont.flags = flags;
+   cont.flushed = true;
+   } else {
+   /*
+* If no fragment of this line ever reached the console,
+* just submit it to the store and free the buffer.
+*/
+   log_store(cont.facility, cont.level, flags, 0,
+ NULL, 0, cont.buf, cont.len);
+   cont.len = 0;
+   }
+}
+
+static bool cont_add(int facility, int level, const char *text, size_t len)
+{
+   if (cont.len && cont.flushed)
+   return false;
+
+   /*
+* If ext consoles are present, flush and skip in-kernel
+* continuation.  See nr_ext_console_drivers definition.  Also, if
+* the line gets too long, split it up in separate records.
+*/
+   if (nr_ext_console_drivers || cont.len + len > sizeof(cont.buf)) {
+   cont_flush(LOG_CONT);
+   return false;
+   }
+
+   if (!cont.len) {
+   cont.facility = facility;
+   cont.level = level;
+   cont.owner = current;
+   cont.ts_nsec = local_clock();
+   cont.flags = 0;
+   cont.cons = 0;
+   cont.flushed = false;
+   }
+
+   memcpy(cont.buf + cont.len, text, len);
+   cont.len += len;
+
+   if (cont.len > (sizeof(cont.buf) * 80) / 100)
+   cont_flush(LOG_CONT);
+
+   return true;
+}
+
+static size_t cont_print_text(char *text, size_t size)
+{
+   size_t textlen = 0;
+   size_t len;
+
+   if (cont.cons == 0 && (console_prev & LOG_NEWLINE)) {
+   textlen += print_time(cont.ts_nsec, text);
+   size -= textlen;
+   }
+
+   len = cont.len - cont.cons;
+   if (len > 0) {
+   if (len+1 > size)
+   len = size-1;
+   memcpy(text + textlen, cont.buf + cont.cons, len);
+   textlen += len;
+   cont.cons = cont.len;
+   }
+
+   if (cont.flushed) {
+   if (cont.flags & LOG_NEWLINE)
+   text[textlen++] = '\n';
+   /* got everything, release buffer */
+   cont.len = 0;
+   }
+   return textlen;
+}
+
 int dmesg_restrict = IS_ENABLED(CONFIG_SECURITY_DMESG_RESTRICT);
 
 static int 

Re: [RFC v2 1/9] printk: move code regarding log message storing format

[Joe Perches]

On Mon, 2015-10-12 at 11:29 +0200, Paul Osmialowski wrote:
> From: Marcin Niesluchowski 
> 
> Preparation commit for future changes purpose.
> 
> Moves some code responsible for storing log messages in proper format.

Perhaps better still would be to move the code into
a separate file to reduce the bulk and complexity
of printk.c

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To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/