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-rw-r--r--Documentation/lockstat.txt120
-rw-r--r--Documentation/sysrq.txt2
-rw-r--r--arch/i386/kernel/cpu/cpufreq/longhaul.c60
-rw-r--r--drivers/char/vt_ioctl.c4
-rw-r--r--drivers/serial/serial_cs.c1
-rw-r--r--include/linux/sched.h2
-rw-r--r--kernel/signal.c22
-rw-r--r--kernel/time/timer_stats.c5
-rw-r--r--lib/Kconfig.debug2
-rw-r--r--lib/Makefile4
10 files changed, 200 insertions, 22 deletions
diff --git a/Documentation/lockstat.txt b/Documentation/lockstat.txt
new file mode 100644
index 00000000000..4ba4664ce5c
--- /dev/null
+++ b/Documentation/lockstat.txt
@@ -0,0 +1,120 @@
+
+LOCK STATISTICS
+
+- WHAT
+
+As the name suggests, it provides statistics on locks.
+
+- WHY
+
+Because things like lock contention can severely impact performance.
+
+- HOW
+
+Lockdep already has hooks in the lock functions and maps lock instances to
+lock classes. We build on that. The graph below shows the relation between
+the lock functions and the various hooks therein.
+
+ __acquire
+ |
+ lock _____
+ | \
+ | __contended
+ | |
+ | <wait>
+ | _______/
+ |/
+ |
+ __acquired
+ |
+ .
+ <hold>
+ .
+ |
+ __release
+ |
+ unlock
+
+lock, unlock - the regular lock functions
+__* - the hooks
+<> - states
+
+With these hooks we provide the following statistics:
+
+ con-bounces - number of lock contention that involved x-cpu data
+ contentions - number of lock acquisitions that had to wait
+ wait time min - shortest (non-0) time we ever had to wait for a lock
+ max - longest time we ever had to wait for a lock
+ total - total time we spend waiting on this lock
+ acq-bounces - number of lock acquisitions that involved x-cpu data
+ acquisitions - number of times we took the lock
+ hold time min - shortest (non-0) time we ever held the lock
+ max - longest time we ever held the lock
+ total - total time this lock was held
+
+From these number various other statistics can be derived, such as:
+
+ hold time average = hold time total / acquisitions
+
+These numbers are gathered per lock class, per read/write state (when
+applicable).
+
+It also tracks 4 contention points per class. A contention point is a call site
+that had to wait on lock acquisition.
+
+ - USAGE
+
+Look at the current lock statistics:
+
+( line numbers not part of actual output, done for clarity in the explanation
+ below )
+
+# less /proc/lock_stat
+
+01 lock_stat version 0.2
+02 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+03 class name con-bounces contentions waittime-min waittime-max waittime-total acq-bounces acquisitions holdtime-min holdtime-max holdtime-total
+04 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+05
+06 &inode->i_data.tree_lock-W: 15 21657 0.18 1093295.30 11547131054.85 58 10415 0.16 87.51 6387.60
+07 &inode->i_data.tree_lock-R: 0 0 0.00 0.00 0.00 23302 231198 0.25 8.45 98023.38
+08 --------------------------
+09 &inode->i_data.tree_lock 0 [<ffffffff8027c08f>] add_to_page_cache+0x5f/0x190
+10
+11 ...............................................................................................................................................................................................
+12
+13 dcache_lock: 1037 1161 0.38 45.32 774.51 6611 243371 0.15 306.48 77387.24
+14 -----------
+15 dcache_lock 180 [<ffffffff802c0d7e>] sys_getcwd+0x11e/0x230
+16 dcache_lock 165 [<ffffffff802c002a>] d_alloc+0x15a/0x210
+17 dcache_lock 33 [<ffffffff8035818d>] _atomic_dec_and_lock+0x4d/0x70
+18 dcache_lock 1 [<ffffffff802beef8>] shrink_dcache_parent+0x18/0x130
+
+This excerpt shows the first two lock class statistics. Line 01 shows the
+output version - each time the format changes this will be updated. Line 02-04
+show the header with column descriptions. Lines 05-10 and 13-18 show the actual
+statistics. These statistics come in two parts; the actual stats separated by a
+short separator (line 08, 14) from the contention points.
+
+The first lock (05-10) is a read/write lock, and shows two lines above the
+short separator. The contention points don't match the column descriptors,
+they have two: contentions and [<IP>] symbol.
+
+
+View the top contending locks:
+
+# grep : /proc/lock_stat | head
+ &inode->i_data.tree_lock-W: 15 21657 0.18 1093295.30 11547131054.85 58 10415 0.16 87.51 6387.60
+ &inode->i_data.tree_lock-R: 0 0 0.00 0.00 0.00 23302 231198 0.25 8.45 98023.38
+ dcache_lock: 1037 1161 0.38 45.32 774.51 6611 243371 0.15 306.48 77387.24
+ &inode->i_mutex: 161 286 18446744073709 62882.54 1244614.55 3653 20598 18446744073709 62318.60 1693822.74
+ &zone->lru_lock: 94 94 0.53 7.33 92.10 4366 32690 0.29 59.81 16350.06
+ &inode->i_data.i_mmap_lock: 79 79 0.40 3.77 53.03 11779 87755 0.28 116.93 29898.44
+ &q->__queue_lock: 48 50 0.52 31.62 86.31 774 13131 0.17 113.08 12277.52
+ &rq->rq_lock_key: 43 47 0.74 68.50 170.63 3706 33929 0.22 107.99 17460.62
+ &rq->rq_lock_key#2: 39 46 0.75 6.68 49.03 2979 32292 0.17 125.17 17137.63
+ tasklist_lock-W: 15 15 1.45 10.87 32.70 1201 7390 0.58 62.55 13648.47
+
+Clear the statistics:
+
+# echo 0 > /proc/lock_stat
diff --git a/Documentation/sysrq.txt b/Documentation/sysrq.txt
index ef19142896c..10c8f6922ef 100644
--- a/Documentation/sysrq.txt
+++ b/Documentation/sysrq.txt
@@ -43,7 +43,7 @@ On x86 - You press the key combo 'ALT-SysRq-<command key>'. Note - Some
keyboards may not have a key labeled 'SysRq'. The 'SysRq' key is
also known as the 'Print Screen' key. Also some keyboards cannot
handle so many keys being pressed at the same time, so you might
- have better luck with "press Alt", "press SysRq", "release Alt",
+ have better luck with "press Alt", "press SysRq", "release SysRq",
"press <command key>", release everything.
On SPARC - You press 'ALT-STOP-<command key>', I believe.
diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
index ef8f0bc3fc7..f0cce3c2dc3 100644
--- a/arch/i386/kernel/cpu/cpufreq/longhaul.c
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -76,6 +76,7 @@ static unsigned int longhaul_index;
/* Module parameters */
static int scale_voltage;
static int disable_acpi_c3;
+static int revid_errata;
#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "longhaul", msg)
@@ -168,7 +169,10 @@ static void do_powersaver(int cx_address, unsigned int clock_ratio_index,
rdmsrl(MSR_VIA_LONGHAUL, longhaul.val);
/* Setup new frequency */
- longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
+ if (!revid_errata)
+ longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
+ else
+ longhaul.bits.RevisionKey = 0;
longhaul.bits.SoftBusRatio = clock_ratio_index & 0xf;
longhaul.bits.SoftBusRatio4 = (clock_ratio_index & 0x10) >> 4;
/* Setup new voltage */
@@ -272,7 +276,7 @@ static void longhaul_setstate(unsigned int table_index)
dprintk ("Setting to FSB:%dMHz Mult:%d.%dx (%s)\n",
fsb, mult/10, mult%10, print_speed(speed/1000));
-
+retry_loop:
preempt_disable();
local_irq_save(flags);
@@ -344,6 +348,47 @@ static void longhaul_setstate(unsigned int table_index)
preempt_enable();
freqs.new = calc_speed(longhaul_get_cpu_mult());
+ /* Check if requested frequency is set. */
+ if (unlikely(freqs.new != speed)) {
+ printk(KERN_INFO PFX "Failed to set requested frequency!\n");
+ /* Revision ID = 1 but processor is expecting revision key
+ * equal to 0. Jumpers at the bottom of processor will change
+ * multiplier and FSB, but will not change bits in Longhaul
+ * MSR nor enable voltage scaling. */
+ if (!revid_errata) {
+ printk(KERN_INFO PFX "Enabling \"Ignore Revision ID\" "
+ "option.\n");
+ revid_errata = 1;
+ msleep(200);
+ goto retry_loop;
+ }
+ /* Why ACPI C3 sometimes doesn't work is a mystery for me.
+ * But it does happen. Processor is entering ACPI C3 state,
+ * but it doesn't change frequency. I tried poking various
+ * bits in northbridge registers, but without success. */
+ if (longhaul_flags & USE_ACPI_C3) {
+ printk(KERN_INFO PFX "Disabling ACPI C3 support.\n");
+ longhaul_flags &= ~USE_ACPI_C3;
+ if (revid_errata) {
+ printk(KERN_INFO PFX "Disabling \"Ignore "
+ "Revision ID\" option.\n");
+ revid_errata = 0;
+ }
+ msleep(200);
+ goto retry_loop;
+ }
+ /* This shouldn't happen. Longhaul ver. 2 was reported not
+ * working on processors without voltage scaling, but with
+ * RevID = 1. RevID errata will make things right. Just
+ * to be 100% sure. */
+ if (longhaul_version == TYPE_LONGHAUL_V2) {
+ printk(KERN_INFO PFX "Switching to Longhaul ver. 1\n");
+ longhaul_version = TYPE_LONGHAUL_V1;
+ msleep(200);
+ goto retry_loop;
+ }
+ }
+ /* Report true CPU frequency */
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
if (!bm_timeout)
@@ -956,11 +1001,20 @@ static void __exit longhaul_exit(void)
kfree(longhaul_table);
}
+/* Even if BIOS is exporting ACPI C3 state, and it is used
+ * with success when CPU is idle, this state doesn't
+ * trigger frequency transition in some cases. */
module_param (disable_acpi_c3, int, 0644);
MODULE_PARM_DESC(disable_acpi_c3, "Don't use ACPI C3 support");
-
+/* Change CPU voltage with frequency. Very usefull to save
+ * power, but most VIA C3 processors aren't supporting it. */
module_param (scale_voltage, int, 0644);
MODULE_PARM_DESC(scale_voltage, "Scale voltage of processor");
+/* Force revision key to 0 for processors which doesn't
+ * support voltage scaling, but are introducing itself as
+ * such. */
+module_param(revid_errata, int, 0644);
+MODULE_PARM_DESC(revid_errata, "Ignore CPU Revision ID");
MODULE_AUTHOR ("Dave Jones <davej@codemonkey.org.uk>");
MODULE_DESCRIPTION ("Longhaul driver for VIA Cyrix processors.");
diff --git a/drivers/char/vt_ioctl.c b/drivers/char/vt_ioctl.c
index c799b7f7bbb..7a61a2a9aaf 100644
--- a/drivers/char/vt_ioctl.c
+++ b/drivers/char/vt_ioctl.c
@@ -1032,7 +1032,7 @@ static DECLARE_WAIT_QUEUE_HEAD(vt_activate_queue);
/*
* Sleeps until a vt is activated, or the task is interrupted. Returns
- * 0 if activation, -EINTR if interrupted.
+ * 0 if activation, -EINTR if interrupted by a signal handler.
*/
int vt_waitactive(int vt)
{
@@ -1057,7 +1057,7 @@ int vt_waitactive(int vt)
break;
}
release_console_sem();
- retval = -EINTR;
+ retval = -ERESTARTNOHAND;
if (signal_pending(current))
break;
schedule();
diff --git a/drivers/serial/serial_cs.c b/drivers/serial/serial_cs.c
index a0ea4359851..7c8d78fbbbf 100644
--- a/drivers/serial/serial_cs.c
+++ b/drivers/serial/serial_cs.c
@@ -943,6 +943,7 @@ static struct pcmcia_device_id serial_ids[] = {
PCMCIA_MFC_DEVICE_PROD_ID12(1,"Elan","Serial Port: SL432",0x3beb8cf2,0x1cce7ac4),
PCMCIA_MFC_DEVICE_PROD_ID12(2,"Elan","Serial Port: SL432",0x3beb8cf2,0x1cce7ac4),
PCMCIA_MFC_DEVICE_PROD_ID12(3,"Elan","Serial Port: SL432",0x3beb8cf2,0x1cce7ac4),
+ PCMCIA_DEVICE_MANF_CARD(0x0279, 0x950b),
/* too generic */
/* PCMCIA_MFC_DEVICE_MANF_CARD(0, 0x0160, 0x0002), */
/* PCMCIA_MFC_DEVICE_MANF_CARD(1, 0x0160, 0x0002), */
diff --git a/include/linux/sched.h b/include/linux/sched.h
index a01ac6dd5f5..313c6b6e774 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -113,7 +113,7 @@ extern unsigned long avenrun[]; /* Load averages */
#define FSHIFT 11 /* nr of bits of precision */
#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
-#define LOAD_FREQ (5*HZ) /* 5 sec intervals */
+#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
#define EXP_5 2014 /* 1/exp(5sec/5min) */
#define EXP_15 2037 /* 1/exp(5sec/15min) */
diff --git a/kernel/signal.c b/kernel/signal.c
index 9fb91a32edd..79295238109 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -531,18 +531,18 @@ static int check_kill_permission(int sig, struct siginfo *info,
if (!valid_signal(sig))
return error;
- error = audit_signal_info(sig, t); /* Let audit system see the signal */
- if (error)
- return error;
-
- error = -EPERM;
- if ((info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info)))
- && ((sig != SIGCONT) ||
- (process_session(current) != process_session(t)))
- && (current->euid ^ t->suid) && (current->euid ^ t->uid)
- && (current->uid ^ t->suid) && (current->uid ^ t->uid)
- && !capable(CAP_KILL))
+ if (info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info))) {
+ error = audit_signal_info(sig, t); /* Let audit system see the signal */
+ if (error)
+ return error;
+ error = -EPERM;
+ if (((sig != SIGCONT) ||
+ (process_session(current) != process_session(t)))
+ && (current->euid ^ t->suid) && (current->euid ^ t->uid)
+ && (current->uid ^ t->suid) && (current->uid ^ t->uid)
+ && !capable(CAP_KILL))
return error;
+ }
return security_task_kill(t, info, sig, 0);
}
diff --git a/kernel/time/timer_stats.c b/kernel/time/timer_stats.c
index 3c38fb5eae1..c36bb7ed030 100644
--- a/kernel/time/timer_stats.c
+++ b/kernel/time/timer_stats.c
@@ -327,8 +327,9 @@ static int tstats_show(struct seq_file *m, void *v)
ms = 1;
if (events && period.tv_sec)
- seq_printf(m, "%ld total events, %ld.%ld events/sec\n", events,
- events / period.tv_sec, events * 1000 / ms);
+ seq_printf(m, "%ld total events, %ld.%03ld events/sec\n",
+ events, events * 1000 / ms,
+ (events * 1000000 / ms) % 1000);
else
seq_printf(m, "%ld total events\n", events);
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 495863a500c..cdc9b099e62 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -294,6 +294,8 @@ config LOCK_STAT
help
This feature enables tracking lock contention points
+ For more details, see Documentation/lockstat.txt
+
config DEBUG_LOCKDEP
bool "Lock dependency engine debugging"
depends on DEBUG_KERNEL && LOCKDEP
diff --git a/lib/Makefile b/lib/Makefile
index 6b0ba8cf4e5..4f3f3e25650 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -2,7 +2,7 @@
# Makefile for some libs needed in the kernel.
#
-lib-y := ctype.o string.o vsprintf.o kasprintf.o cmdline.o \
+lib-y := ctype.o string.o vsprintf.o cmdline.o \
rbtree.o radix-tree.o dump_stack.o \
idr.o int_sqrt.o bitmap.o extable.o prio_tree.o \
sha1.o irq_regs.o reciprocal_div.o argv_split.o
@@ -13,7 +13,7 @@ lib-$(CONFIG_SMP) += cpumask.o
lib-y += kobject.o kref.o kobject_uevent.o klist.o
obj-y += div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
- bust_spinlocks.o hexdump.o
+ bust_spinlocks.o hexdump.o kasprintf.o
ifeq ($(CONFIG_DEBUG_KOBJECT),y)
CFLAGS_kobject.o += -DDEBUG
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-26 05:44:22 +0000