Linemode seems to add a newline for each sent message which makes
reading rather hard. Hence we add a small buffer and only print if
it's full or a newline is encountered. Except for when the string is
longer than the buffer, then we flush the buffer and print directly.
Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
Reviewed-by: Thomas Huth <thuth@xxxxxxxxxx>
---
How about something like this, splitting buffer handling and actual
printing, while adding buffer that's separate from the sclp locking. I
hope that all offsets and ptrs are correct despite the weekday and
hour...
---
lib/s390x/sclp-console.c | 71 +++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 67 insertions(+), 4 deletions(-)
diff --git a/lib/s390x/sclp-console.c b/lib/s390x/sclp-console.c
index 19416b5..4db09c4 100644
--- a/lib/s390x/sclp-console.c
+++ b/lib/s390x/sclp-console.c
@@ -13,6 +13,7 @@
#include <asm/page.h>
#include <asm/arch_def.h>
#include <asm/io.h>
+#include <asm/spinlock.h>
#include "sclp.h"
/*
@@ -87,6 +88,11 @@ static uint8_t _ascebc[256] = {
0x90, 0x3F, 0x3F, 0x3F, 0x3F, 0xEA, 0x3F, 0xFF
};
+static char lm_buff[120];
+static unsigned char lm_buff_off;
+static struct spinlock lm_buff_lock;
+
+
static void sclp_print_ascii(const char *str)
{
int len = strlen(str);
@@ -103,10 +109,10 @@ static void sclp_print_ascii(const char *str)
sclp_service_call(SCLP_CMD_WRITE_EVENT_DATA, sccb);
}
-static void sclp_print_lm(const char *str)
+static void lm_print(const char *buff, int len)
{
unsigned char *ptr, *end, ch;
- unsigned int count, offset, len;
+ unsigned int count, offset;
struct WriteEventData *sccb;
struct mdb *mdb;
struct mto *mto;
@@ -117,11 +123,10 @@ static void sclp_print_lm(const char *str)
end = (unsigned char *) sccb + 4096 - 1;
memset(sccb, 0, sizeof(*sccb));
ptr = (unsigned char *) &sccb->msg.mdb.mto;
- len = strlen(str);
offset = 0;
do {
for (count = sizeof(*mto); offset < len; count++) {
- ch = str[offset++];
+ ch = buff[offset++];
if (ch == 0x0a || ptr + count > end)
break;
ptr[count] = _ascebc[ch];
@@ -148,6 +153,64 @@ static void sclp_print_lm(const char *str)
sclp_service_call(SCLP_CMD_WRITE_EVENT_DATA, sccb);
}
+
+/*
+ * In contrast to the ascii console, linemode produces a new
+ * line with every write of data. The report() function uses
+ * several printf() calls to generate a line of data which
+ * would all end up on different lines.
+ *
+ * Hence we buffer here until we encounter a \n or the buffer
+ * is full. That means that linemode output can look a bit
+ * different from ascii and that it takes a bit longer for
+ * lines to appear.
+ */
+static void sclp_print_lm(const char *str)
+{
+ int len;
+ char *nl;
+
+ spin_lock(&lm_buff_lock);
+
+ len = strlen(str);
+ /*
+ * No use in copying into lm_buff, its time to flush the
+ * buffer and print str until finished.
+ */
+ if (len > sizeof(lm_buff)) {
+ if (lm_buff_off)
+ lm_print(lm_buff, lm_buff_off);
+ lm_print(str, len);
+ memset(lm_buff, 0 , sizeof(lm_buff));
+ lm_buff_off = 0;
+ goto out;
+ }
+
+fill:
+ len = len < (sizeof(lm_buff) - lm_buff_off) ? len : (sizeof(lm_buff) - lm_buff_off);
+ if ((lm_buff_off < sizeof(lm_buff) - 1)) {
+ memcpy(&lm_buff[lm_buff_off], str, len);
+ lm_buff_off += len;
+ }
+ /* Buffer not full and no newline */
+ nl = strchr(lm_buff, '\n');
+ if (lm_buff_off != sizeof(lm_buff) - 1 && !nl)
+ goto out;
+
+ lm_print(lm_buff, lm_buff_off);
+ memset(lm_buff, 0 , sizeof(lm_buff));
+ lm_buff_off = 0;
+
+ if (len < strlen(str)) {
+ str = &str[len];
+ len = strlen(str);
+ goto fill;
+ }
+
+out:
+ spin_unlock(&lm_buff_lock);
+}
+
/*
* SCLP needs to be initialized by setting a send and receive mask,
* indicating which messages the control program (we) want(s) to
--
2.14.3
