diff options
Diffstat (limited to 'features/rt/printk-introduce-CONSOLE_LOG_MAX-for-improved-multi-.patch')
| -rw-r--r-- | features/rt/printk-introduce-CONSOLE_LOG_MAX-for-improved-multi-.patch | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/features/rt/printk-introduce-CONSOLE_LOG_MAX-for-improved-multi-.patch b/features/rt/printk-introduce-CONSOLE_LOG_MAX-for-improved-multi-.patch new file mode 100644 index 00000000..70b8eafb --- /dev/null +++ b/features/rt/printk-introduce-CONSOLE_LOG_MAX-for-improved-multi-.patch @@ -0,0 +1,94 @@ +From f0d983447bd8059038b24361b5698ffec757f812 Mon Sep 17 00:00:00 2001 +From: John Ogness <john.ogness@linutronix.de> +Date: Thu, 10 Dec 2020 12:48:01 +0106 +Subject: [PATCH 011/191] printk: introduce CONSOLE_LOG_MAX for improved + multi-line support + +Instead of using "LOG_LINE_MAX + PREFIX_MAX" for temporary buffer +sizes, introduce CONSOLE_LOG_MAX. This represents the maximum size +that is allowed to be printed to the console for a single record. + +Rather than setting CONSOLE_LOG_MAX to "LOG_LINE_MAX + PREFIX_MAX" +(1024), increase it to 4096. With a larger buffer size, multi-line +records that are nearly LOG_LINE_MAX in length will have a better +chance of being fully printed. (When formatting a record for the +console, each line of a multi-line record is prepended with a copy +of the prefix.) + +Signed-off-by: John Ogness <john.ogness@linutronix.de> +--- + kernel/printk/printk.c | 18 +++++++++++------- + 1 file changed, 11 insertions(+), 7 deletions(-) + +diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c +index ff16a29aa620..8a903faaec4e 100644 +--- a/kernel/printk/printk.c ++++ b/kernel/printk/printk.c +@@ -410,8 +410,13 @@ static u64 clear_seq; + #else + #define PREFIX_MAX 32 + #endif ++ ++/* the maximum size allowed to be reserved for a record */ + #define LOG_LINE_MAX (1024 - PREFIX_MAX) + ++/* the maximum size of a formatted record (i.e. with prefix added per line) */ ++#define CONSOLE_LOG_MAX 4096 ++ + #define LOG_LEVEL(v) ((v) & 0x07) + #define LOG_FACILITY(v) ((v) >> 3 & 0xff) + +@@ -1472,11 +1477,11 @@ static int syslog_print(char __user *buf, int size) + char *text; + int len = 0; + +- text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL); ++ text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL); + if (!text) + return -ENOMEM; + +- prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX); ++ prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX); + + while (size > 0) { + size_t n; +@@ -1542,7 +1547,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear) + u64 seq; + bool time; + +- text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL); ++ text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL); + if (!text) + return -ENOMEM; + +@@ -1554,7 +1559,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear) + */ + seq = find_first_fitting_seq(clear_seq, -1, size, true, time); + +- prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX); ++ prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX); + + len = 0; + prb_for_each_record(seq, prb, seq, &r) { +@@ -2187,8 +2192,7 @@ EXPORT_SYMBOL(printk); + + #else /* CONFIG_PRINTK */ + +-#define LOG_LINE_MAX 0 +-#define PREFIX_MAX 0 ++#define CONSOLE_LOG_MAX 0 + #define printk_time false + + #define prb_read_valid(rb, seq, r) false +@@ -2506,7 +2510,7 @@ static inline int can_use_console(void) + void console_unlock(void) + { + static char ext_text[CONSOLE_EXT_LOG_MAX]; +- static char text[LOG_LINE_MAX + PREFIX_MAX]; ++ static char text[CONSOLE_LOG_MAX]; + unsigned long flags; + bool do_cond_resched, retry; + struct printk_info info; +-- +2.19.1 + |