diff options
author | Tejun Heo <tj@kernel.org> | 2011-11-28 09:46:22 -0800 |
---|---|---|
committer | Tejun Heo <tj@kernel.org> | 2011-11-28 09:46:22 -0800 |
commit | d4bbf7e7759afc172e2bfbc5c416324590049cdd (patch) | |
tree | 7eab5ee5481cd3dcf1162329fec827177640018a /kernel/printk.c | |
parent | a150439c4a97db379f0ed6faa46fbbb6e7bf3cb2 (diff) | |
parent | 401d0069cb344f401bc9d264c31db55876ff78c0 (diff) |
Merge branch 'master' into x86/memblock
Conflicts & resolutions:
* arch/x86/xen/setup.c
dc91c728fd "xen: allow extra memory to be in multiple regions"
24aa07882b "memblock, x86: Replace memblock_x86_reserve/free..."
conflicted on xen_add_extra_mem() updates. The resolution is
trivial as the latter just want to replace
memblock_x86_reserve_range() with memblock_reserve().
* drivers/pci/intel-iommu.c
166e9278a3f "x86/ia64: intel-iommu: move to drivers/iommu/"
5dfe8660a3d "bootmem: Replace work_with_active_regions() with..."
conflicted as the former moved the file under drivers/iommu/.
Resolved by applying the chnages from the latter on the moved
file.
* mm/Kconfig
6661672053a "memblock: add NO_BOOTMEM config symbol"
c378ddd53f9 "memblock, x86: Make ARCH_DISCARD_MEMBLOCK a config option"
conflicted trivially. Both added config options. Just
letting both add their own options resolves the conflict.
* mm/memblock.c
d1f0ece6cdc "mm/memblock.c: small function definition fixes"
ed7b56a799c "memblock: Remove memblock_memory_can_coalesce()"
confliected. The former updates function removed by the
latter. Resolution is trivial.
Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'kernel/printk.c')
-rw-r--r-- | kernel/printk.c | 84 |
1 files changed, 54 insertions, 30 deletions
diff --git a/kernel/printk.c b/kernel/printk.c index b1d5a6174d65..baf2aebd6970 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -100,7 +100,7 @@ static int console_locked, console_suspended; * It is also used in interesting ways to provide interlocking in * console_unlock();. */ -static DEFINE_SPINLOCK(logbuf_lock); +static DEFINE_RAW_SPINLOCK(logbuf_lock); #define LOG_BUF_MASK (log_buf_len-1) #define LOG_BUF(idx) (log_buf[(idx) & LOG_BUF_MASK]) @@ -212,7 +212,7 @@ void __init setup_log_buf(int early) return; } - spin_lock_irqsave(&logbuf_lock, flags); + raw_spin_lock_irqsave(&logbuf_lock, flags); log_buf_len = new_log_buf_len; log_buf = new_log_buf; new_log_buf_len = 0; @@ -230,7 +230,7 @@ void __init setup_log_buf(int early) log_start -= offset; con_start -= offset; log_end -= offset; - spin_unlock_irqrestore(&logbuf_lock, flags); + raw_spin_unlock_irqrestore(&logbuf_lock, flags); pr_info("log_buf_len: %d\n", log_buf_len); pr_info("early log buf free: %d(%d%%)\n", @@ -318,8 +318,10 @@ static int check_syslog_permissions(int type, bool from_file) return 0; /* For historical reasons, accept CAP_SYS_ADMIN too, with a warning */ if (capable(CAP_SYS_ADMIN)) { - WARN_ONCE(1, "Attempt to access syslog with CAP_SYS_ADMIN " - "but no CAP_SYSLOG (deprecated).\n"); + printk_once(KERN_WARNING "%s (%d): " + "Attempt to access syslog with CAP_SYS_ADMIN " + "but no CAP_SYSLOG (deprecated).\n", + current->comm, task_pid_nr(current)); return 0; } return -EPERM; @@ -363,18 +365,18 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) if (error) goto out; i = 0; - spin_lock_irq(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); while (!error && (log_start != log_end) && i < len) { c = LOG_BUF(log_start); log_start++; - spin_unlock_irq(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); error = __put_user(c,buf); buf++; i++; cond_resched(); - spin_lock_irq(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); } - spin_unlock_irq(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); if (!error) error = i; break; @@ -397,7 +399,7 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) count = len; if (count > log_buf_len) count = log_buf_len; - spin_lock_irq(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); if (count > logged_chars) count = logged_chars; if (do_clear) @@ -414,12 +416,12 @@ int do_syslog(int type, char __user *buf, int len, bool from_file) if (j + log_buf_len < log_end) break; c = LOG_BUF(j); - spin_unlock_irq(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); error = __put_user(c,&buf[count-1-i]); cond_resched(); - spin_lock_irq(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); } - spin_unlock_irq(&logbuf_lock); + raw_spin_unlock_irq(&logbuf_lock); if (error) break; error = i; @@ -530,6 +532,9 @@ static int __init ignore_loglevel_setup(char *str) } early_param("ignore_loglevel", ignore_loglevel_setup); +module_param_named(ignore_loglevel, ignore_loglevel, bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(ignore_loglevel, "ignore loglevel setting, to" + "print all kernel messages to the console."); /* * Write out chars from start to end - 1 inclusive @@ -590,9 +595,6 @@ static size_t log_prefix(const char *p, unsigned int *level, char *special) /* multi digit including the level and facility number */ char *endp = NULL; - if (p[1] < '0' && p[1] > '9') - return 0; - lev = (simple_strtoul(&p[1], &endp, 10) & 7); if (endp == NULL || endp[0] != '>') return 0; @@ -687,7 +689,7 @@ static void zap_locks(void) oops_timestamp = jiffies; /* If a crash is occurring, make sure we can't deadlock */ - spin_lock_init(&logbuf_lock); + raw_spin_lock_init(&logbuf_lock); /* And make sure that we print immediately */ sema_init(&console_sem, 1); } @@ -782,7 +784,7 @@ static inline int can_use_console(unsigned int cpu) static int console_trylock_for_printk(unsigned int cpu) __releases(&logbuf_lock) { - int retval = 0; + int retval = 0, wake = 0; if (console_trylock()) { retval = 1; @@ -795,12 +797,14 @@ static int console_trylock_for_printk(unsigned int cpu) */ if (!can_use_console(cpu)) { console_locked = 0; - up(&console_sem); + wake = 1; retval = 0; } } printk_cpu = UINT_MAX; - spin_unlock(&logbuf_lock); + if (wake) + up(&console_sem); + raw_spin_unlock(&logbuf_lock); return retval; } static const char recursion_bug_msg [] = @@ -860,7 +864,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) } lockdep_off(); - spin_lock(&logbuf_lock); + raw_spin_lock(&logbuf_lock); printk_cpu = this_cpu; if (recursion_bug) { @@ -1104,6 +1108,10 @@ static int __init console_suspend_disable(char *str) return 1; } __setup("no_console_suspend", console_suspend_disable); +module_param_named(console_suspend, console_suspend_enabled, + bool, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(console_suspend, "suspend console during suspend" + " and hibernate operations"); /** * suspend_console - suspend the console subsystem @@ -1242,7 +1250,7 @@ void console_unlock(void) { unsigned long flags; unsigned _con_start, _log_end; - unsigned wake_klogd = 0; + unsigned wake_klogd = 0, retry = 0; if (console_suspended) { up(&console_sem); @@ -1251,15 +1259,16 @@ void console_unlock(void) console_may_schedule = 0; +again: for ( ; ; ) { - spin_lock_irqsave(&logbuf_lock, flags); + raw_spin_lock_irqsave(&logbuf_lock, flags); wake_klogd |= log_start - log_end; if (con_start == log_end) break; /* Nothing to print */ _con_start = con_start; _log_end = log_end; con_start = log_end; /* Flush */ - spin_unlock(&logbuf_lock); + raw_spin_unlock(&logbuf_lock); stop_critical_timings(); /* don't trace print latency */ call_console_drivers(_con_start, _log_end); start_critical_timings(); @@ -1271,8 +1280,23 @@ void console_unlock(void) if (unlikely(exclusive_console)) exclusive_console = NULL; + raw_spin_unlock(&logbuf_lock); + up(&console_sem); - spin_unlock_irqrestore(&logbuf_lock, flags); + + /* + * Someone could have filled up the buffer again, so re-check if there's + * something to flush. In case we cannot trylock the console_sem again, + * there's a new owner and the console_unlock() from them will do the + * flush, no worries. + */ + raw_spin_lock(&logbuf_lock); + if (con_start != log_end) + retry = 1; + if (retry && console_trylock()) + goto again; + + raw_spin_unlock_irqrestore(&logbuf_lock, flags); if (wake_klogd) wake_up_klogd(); } @@ -1502,9 +1526,9 @@ void register_console(struct console *newcon) * console_unlock(); will print out the buffered messages * for us. */ - spin_lock_irqsave(&logbuf_lock, flags); + raw_spin_lock_irqsave(&logbuf_lock, flags); con_start = log_start; - spin_unlock_irqrestore(&logbuf_lock, flags); + raw_spin_unlock_irqrestore(&logbuf_lock, flags); /* * We're about to replay the log buffer. Only do this to the * just-registered console to avoid excessive message spam to @@ -1584,7 +1608,7 @@ static int __init printk_late_init(void) struct console *con; for_each_console(con) { - if (con->flags & CON_BOOT) { + if (!keep_bootcon && con->flags & CON_BOOT) { printk(KERN_INFO "turn off boot console %s%d\n", con->name, con->index); unregister_console(con); @@ -1711,10 +1735,10 @@ void kmsg_dump(enum kmsg_dump_reason reason) /* Theoretically, the log could move on after we do this, but there's not a lot we can do about that. The new messages will overwrite the start of what we dump. */ - spin_lock_irqsave(&logbuf_lock, flags); + raw_spin_lock_irqsave(&logbuf_lock, flags); end = log_end & LOG_BUF_MASK; chars = logged_chars; - spin_unlock_irqrestore(&logbuf_lock, flags); + raw_spin_unlock_irqrestore(&logbuf_lock, flags); if (chars > end) { s1 = log_buf + log_buf_len - chars + end; |