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-rw-r--r--arch/ia64/kernel/mca.c216
1 files changed, 198 insertions, 18 deletions
diff --git a/arch/ia64/kernel/mca.c b/arch/ia64/kernel/mca.c
index 2fbe4536fe18..98f3b26d7aff 100644
--- a/arch/ia64/kernel/mca.c
+++ b/arch/ia64/kernel/mca.c
@@ -54,6 +54,9 @@
*
* 2005-10-07 Keith Owens <kaos@sgi.com>
* Add notify_die() hooks.
+ *
+ * 2006-09-15 Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
+ * Add printing support for MCA/INIT.
*/
#include <linux/types.h>
#include <linux/init.h>
@@ -136,11 +139,175 @@ extern void salinfo_log_wakeup(int type, u8 *buffer, u64 size, int irqsafe);
static int mca_init __initdata;
+/*
+ * limited & delayed printing support for MCA/INIT handler
+ */
+
+#define mprintk(fmt...) ia64_mca_printk(fmt)
+
+#define MLOGBUF_SIZE (512+256*NR_CPUS)
+#define MLOGBUF_MSGMAX 256
+static char mlogbuf[MLOGBUF_SIZE];
+static DEFINE_SPINLOCK(mlogbuf_wlock); /* mca context only */
+static DEFINE_SPINLOCK(mlogbuf_rlock); /* normal context only */
+static unsigned long mlogbuf_start;
+static unsigned long mlogbuf_end;
+static unsigned int mlogbuf_finished = 0;
+static unsigned long mlogbuf_timestamp = 0;
+
+static int loglevel_save = -1;
+#define BREAK_LOGLEVEL(__console_loglevel) \
+ oops_in_progress = 1; \
+ if (loglevel_save < 0) \
+ loglevel_save = __console_loglevel; \
+ __console_loglevel = 15;
+
+#define RESTORE_LOGLEVEL(__console_loglevel) \
+ if (loglevel_save >= 0) { \
+ __console_loglevel = loglevel_save; \
+ loglevel_save = -1; \
+ } \
+ mlogbuf_finished = 0; \
+ oops_in_progress = 0;
+
+/*
+ * Push messages into buffer, print them later if not urgent.
+ */
+void ia64_mca_printk(const char *fmt, ...)
+{
+ va_list args;
+ int printed_len;
+ char temp_buf[MLOGBUF_MSGMAX];
+ char *p;
+
+ va_start(args, fmt);
+ printed_len = vscnprintf(temp_buf, sizeof(temp_buf), fmt, args);
+ va_end(args);
+
+ /* Copy the output into mlogbuf */
+ if (oops_in_progress) {
+ /* mlogbuf was abandoned, use printk directly instead. */
+ printk(temp_buf);
+ } else {
+ spin_lock(&mlogbuf_wlock);
+ for (p = temp_buf; *p; p++) {
+ unsigned long next = (mlogbuf_end + 1) % MLOGBUF_SIZE;
+ if (next != mlogbuf_start) {
+ mlogbuf[mlogbuf_end] = *p;
+ mlogbuf_end = next;
+ } else {
+ /* buffer full */
+ break;
+ }
+ }
+ mlogbuf[mlogbuf_end] = '\0';
+ spin_unlock(&mlogbuf_wlock);
+ }
+}
+EXPORT_SYMBOL(ia64_mca_printk);
+
+/*
+ * Print buffered messages.
+ * NOTE: call this after returning normal context. (ex. from salinfod)
+ */
+void ia64_mlogbuf_dump(void)
+{
+ char temp_buf[MLOGBUF_MSGMAX];
+ char *p;
+ unsigned long index;
+ unsigned long flags;
+ unsigned int printed_len;
+
+ /* Get output from mlogbuf */
+ while (mlogbuf_start != mlogbuf_end) {
+ temp_buf[0] = '\0';
+ p = temp_buf;
+ printed_len = 0;
+
+ spin_lock_irqsave(&mlogbuf_rlock, flags);
+
+ index = mlogbuf_start;
+ while (index != mlogbuf_end) {
+ *p = mlogbuf[index];
+ index = (index + 1) % MLOGBUF_SIZE;
+ if (!*p)
+ break;
+ p++;
+ if (++printed_len >= MLOGBUF_MSGMAX - 1)
+ break;
+ }
+ *p = '\0';
+ if (temp_buf[0])
+ printk(temp_buf);
+ mlogbuf_start = index;
+
+ mlogbuf_timestamp = 0;
+ spin_unlock_irqrestore(&mlogbuf_rlock, flags);
+ }
+}
+EXPORT_SYMBOL(ia64_mlogbuf_dump);
+
+/*
+ * Call this if system is going to down or if immediate flushing messages to
+ * console is required. (ex. recovery was failed, crash dump is going to be
+ * invoked, long-wait rendezvous etc.)
+ * NOTE: this should be called from monarch.
+ */
+static void ia64_mlogbuf_finish(int wait)
+{
+ BREAK_LOGLEVEL(console_loglevel);
+
+ spin_lock_init(&mlogbuf_rlock);
+ ia64_mlogbuf_dump();
+ printk(KERN_EMERG "mlogbuf_finish: printing switched to urgent mode, "
+ "MCA/INIT might be dodgy or fail.\n");
+
+ if (!wait)
+ return;
+
+ /* wait for console */
+ printk("Delaying for 5 seconds...\n");
+ udelay(5*1000000);
+
+ mlogbuf_finished = 1;
+}
+EXPORT_SYMBOL(ia64_mlogbuf_finish);
+
+/*
+ * Print buffered messages from INIT context.
+ */
+static void ia64_mlogbuf_dump_from_init(void)
+{
+ if (mlogbuf_finished)
+ return;
+
+ if (mlogbuf_timestamp && (mlogbuf_timestamp + 30*HZ > jiffies)) {
+ printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT "
+ " and the system seems to be messed up.\n");
+ ia64_mlogbuf_finish(0);
+ return;
+ }
+
+ if (!spin_trylock(&mlogbuf_rlock)) {
+ printk(KERN_ERR "INIT: mlogbuf_dump is interrupted by INIT. "
+ "Generated messages other than stack dump will be "
+ "buffered to mlogbuf and will be printed later.\n");
+ printk(KERN_ERR "INIT: If messages would not printed after "
+ "this INIT, wait 30sec and assert INIT again.\n");
+ if (!mlogbuf_timestamp)
+ mlogbuf_timestamp = jiffies;
+ return;
+ }
+ spin_unlock(&mlogbuf_rlock);
+ ia64_mlogbuf_dump();
+}
static void inline
ia64_mca_spin(const char *func)
{
- printk(KERN_EMERG "%s: spinning here, not returning to SAL\n", func);
+ if (monarch_cpu == smp_processor_id())
+ ia64_mlogbuf_finish(0);
+ mprintk(KERN_EMERG "%s: spinning here, not returning to SAL\n", func);
while (1)
cpu_relax();
}
@@ -988,18 +1155,22 @@ ia64_wait_for_slaves(int monarch, const char *type)
}
if (!missing)
goto all_in;
- printk(KERN_INFO "OS %s slave did not rendezvous on cpu", type);
+ /*
+ * Maybe slave(s) dead. Print buffered messages immediately.
+ */
+ ia64_mlogbuf_finish(0);
+ mprintk(KERN_INFO "OS %s slave did not rendezvous on cpu", type);
for_each_online_cpu(c) {
if (c == monarch)
continue;
if (ia64_mc_info.imi_rendez_checkin[c] == IA64_MCA_RENDEZ_CHECKIN_NOTDONE)
- printk(" %d", c);
+ mprintk(" %d", c);
}
- printk("\n");
+ mprintk("\n");
return;
all_in:
- printk(KERN_INFO "All OS %s slaves have reached rendezvous\n", type);
+ mprintk(KERN_INFO "All OS %s slaves have reached rendezvous\n", type);
return;
}
@@ -1027,10 +1198,8 @@ ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw,
struct ia64_mca_notify_die nd =
{ .sos = sos, .monarch_cpu = &monarch_cpu };
- oops_in_progress = 1; /* FIXME: make printk NMI/MCA/INIT safe */
- console_loglevel = 15; /* make sure printks make it to console */
- printk(KERN_INFO "Entered OS MCA handler. PSP=%lx cpu=%d monarch=%ld\n",
- sos->proc_state_param, cpu, sos->monarch);
+ mprintk(KERN_INFO "Entered OS MCA handler. PSP=%lx cpu=%d "
+ "monarch=%ld\n", sos->proc_state_param, cpu, sos->monarch);
previous_current = ia64_mca_modify_original_stack(regs, sw, sos, "MCA");
monarch_cpu = cpu;
@@ -1066,6 +1235,9 @@ ia64_mca_handler(struct pt_regs *regs, struct switch_stack *sw,
rh->severity = sal_log_severity_corrected;
ia64_sal_clear_state_info(SAL_INFO_TYPE_MCA);
sos->os_status = IA64_MCA_CORRECTED;
+ } else {
+ /* Dump buffered message to console */
+ ia64_mlogbuf_finish(1);
}
if (notify_die(DIE_MCA_MONARCH_LEAVE, "MCA", regs, (long)&nd, 0, recover)
== NOTIFY_STOP)
@@ -1305,6 +1477,15 @@ default_monarch_init_process(struct notifier_block *self, unsigned long val, voi
struct task_struct *g, *t;
if (val != DIE_INIT_MONARCH_PROCESS)
return NOTIFY_DONE;
+
+ /*
+ * FIXME: mlogbuf will brim over with INIT stack dumps.
+ * To enable show_stack from INIT, we use oops_in_progress which should
+ * be used in real oops. This would cause something wrong after INIT.
+ */
+ BREAK_LOGLEVEL(console_loglevel);
+ ia64_mlogbuf_dump_from_init();
+
printk(KERN_ERR "Processes interrupted by INIT -");
for_each_online_cpu(c) {
struct ia64_sal_os_state *s;
@@ -1326,6 +1507,8 @@ default_monarch_init_process(struct notifier_block *self, unsigned long val, voi
} while_each_thread (g, t);
read_unlock(&tasklist_lock);
}
+ /* FIXME: This will not restore zapped printk locks. */
+ RESTORE_LOGLEVEL(console_loglevel);
return NOTIFY_DONE;
}
@@ -1357,12 +1540,9 @@ ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
struct ia64_mca_notify_die nd =
{ .sos = sos, .monarch_cpu = &monarch_cpu };
- oops_in_progress = 1; /* FIXME: make printk NMI/MCA/INIT safe */
- console_loglevel = 15; /* make sure printks make it to console */
-
(void) notify_die(DIE_INIT_ENTER, "INIT", regs, (long)&nd, 0, 0);
- printk(KERN_INFO "Entered OS INIT handler. PSP=%lx cpu=%d monarch=%ld\n",
+ mprintk(KERN_INFO "Entered OS INIT handler. PSP=%lx cpu=%d monarch=%ld\n",
sos->proc_state_param, cpu, sos->monarch);
salinfo_log_wakeup(SAL_INFO_TYPE_INIT, NULL, 0, 0);
@@ -1375,7 +1555,7 @@ ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
* fix their proms and get their customers updated.
*/
if (!sos->monarch && atomic_add_return(1, &slaves) == num_online_cpus()) {
- printk(KERN_WARNING "%s: Promoting cpu %d to monarch.\n",
+ mprintk(KERN_WARNING "%s: Promoting cpu %d to monarch.\n",
__FUNCTION__, cpu);
atomic_dec(&slaves);
sos->monarch = 1;
@@ -1387,7 +1567,7 @@ ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
* fix their proms and get their customers updated.
*/
if (sos->monarch && atomic_add_return(1, &monarchs) > 1) {
- printk(KERN_WARNING "%s: Demoting cpu %d to slave.\n",
+ mprintk(KERN_WARNING "%s: Demoting cpu %d to slave.\n",
__FUNCTION__, cpu);
atomic_dec(&monarchs);
sos->monarch = 0;
@@ -1408,7 +1588,7 @@ ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
if (notify_die(DIE_INIT_SLAVE_LEAVE, "INIT", regs, (long)&nd, 0, 0)
== NOTIFY_STOP)
ia64_mca_spin(__FUNCTION__);
- printk("Slave on cpu %d returning to normal service.\n", cpu);
+ mprintk("Slave on cpu %d returning to normal service.\n", cpu);
set_curr_task(cpu, previous_current);
ia64_mc_info.imi_rendez_checkin[cpu] = IA64_MCA_RENDEZ_CHECKIN_NOTDONE;
atomic_dec(&slaves);
@@ -1426,7 +1606,7 @@ ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
* same serial line, the user will need some time to switch out of the BMC before
* the dump begins.
*/
- printk("Delaying for 5 seconds...\n");
+ mprintk("Delaying for 5 seconds...\n");
udelay(5*1000000);
ia64_wait_for_slaves(cpu, "INIT");
/* If nobody intercepts DIE_INIT_MONARCH_PROCESS then we drop through
@@ -1439,7 +1619,7 @@ ia64_init_handler(struct pt_regs *regs, struct switch_stack *sw,
if (notify_die(DIE_INIT_MONARCH_LEAVE, "INIT", regs, (long)&nd, 0, 0)
== NOTIFY_STOP)
ia64_mca_spin(__FUNCTION__);
- printk("\nINIT dump complete. Monarch on cpu %d returning to normal service.\n", cpu);
+ mprintk("\nINIT dump complete. Monarch on cpu %d returning to normal service.\n", cpu);
atomic_dec(&monarchs);
set_curr_task(cpu, previous_current);
monarch_cpu = -1;
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