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authorLinus Torvalds <torvalds@linux-foundation.org>2016-03-18 19:26:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-18 19:26:54 -0700
commit814a2bf957739f367cbebfa1b60237387b72d0ee (patch)
tree8d65c38d14beb8d6d2dc5b9d7f8dbe63c7cad31a /kernel
parent237045fc3c67d44088f767dca5a9fa30815eba62 (diff)
parentf9310b2f9a19b7f16c7b1c1558f8b649b9b933c1 (diff)
Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton: - a couple of hotfixes - the rest of MM - a new timer slack control in procfs - a couple of procfs fixes - a few misc things - some printk tweaks - lib/ updates, notably to radix-tree. - add my and Nick Piggin's old userspace radix-tree test harness to tools/testing/radix-tree/. Matthew said it was a godsend during the radix-tree work he did. - a few code-size improvements, switching to __always_inline where gcc screwed up. - partially implement character sets in sscanf * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits) sscanf: implement basic character sets lib/bug.c: use common WARN helper param: convert some "on"/"off" users to strtobool lib: add "on"/"off" support to kstrtobool lib: update single-char callers of strtobool() lib: move strtobool() to kstrtobool() include/linux/unaligned: force inlining of byteswap operations include/uapi/linux/byteorder, swab: force inlining of some byteswap operations include/asm-generic/atomic-long.h: force inlining of some atomic_long operations usb: common: convert to use match_string() helper ide: hpt366: convert to use match_string() helper ata: hpt366: convert to use match_string() helper power: ab8500: convert to use match_string() helper power: charger_manager: convert to use match_string() helper drm/edid: convert to use match_string() helper pinctrl: convert to use match_string() helper device property: convert to use match_string() helper lib/string: introduce match_string() helper radix-tree tests: add test for radix_tree_iter_next radix-tree tests: add regression3 test ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/fork.c10
-rw-r--r--kernel/panic.c41
-rw-r--r--kernel/printk/printk.c140
-rw-r--r--kernel/sys.c5
-rw-r--r--kernel/sysctl.c10
-rw-r--r--kernel/time/hrtimer.c18
-rw-r--r--kernel/time/tick-sched.c10
-rw-r--r--kernel/time/timer.c4
-rw-r--r--kernel/watchdog.c9
9 files changed, 133 insertions, 114 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 2e391c754ae7..accb7221d547 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -164,12 +164,20 @@ static struct thread_info *alloc_thread_info_node(struct task_struct *tsk,
struct page *page = alloc_kmem_pages_node(node, THREADINFO_GFP,
THREAD_SIZE_ORDER);
+ if (page)
+ memcg_kmem_update_page_stat(page, MEMCG_KERNEL_STACK,
+ 1 << THREAD_SIZE_ORDER);
+
return page ? page_address(page) : NULL;
}
static inline void free_thread_info(struct thread_info *ti)
{
- free_kmem_pages((unsigned long)ti, THREAD_SIZE_ORDER);
+ struct page *page = virt_to_page(ti);
+
+ memcg_kmem_update_page_stat(page, MEMCG_KERNEL_STACK,
+ -(1 << THREAD_SIZE_ORDER));
+ __free_kmem_pages(page, THREAD_SIZE_ORDER);
}
# else
static struct kmem_cache *thread_info_cache;
diff --git a/kernel/panic.c b/kernel/panic.c
index d96469de72dc..fa400852bf6c 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -24,6 +24,7 @@
#include <linux/init.h>
#include <linux/nmi.h>
#include <linux/console.h>
+#include <linux/bug.h>
#define PANIC_TIMER_STEP 100
#define PANIC_BLINK_SPD 18
@@ -449,20 +450,25 @@ void oops_exit(void)
kmsg_dump(KMSG_DUMP_OOPS);
}
-#ifdef WANT_WARN_ON_SLOWPATH
-struct slowpath_args {
+struct warn_args {
const char *fmt;
va_list args;
};
-static void warn_slowpath_common(const char *file, int line, void *caller,
- unsigned taint, struct slowpath_args *args)
+void __warn(const char *file, int line, void *caller, unsigned taint,
+ struct pt_regs *regs, struct warn_args *args)
{
disable_trace_on_warning();
pr_warn("------------[ cut here ]------------\n");
- pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS()\n",
- raw_smp_processor_id(), current->pid, file, line, caller);
+
+ if (file)
+ pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS\n",
+ raw_smp_processor_id(), current->pid, file, line,
+ caller);
+ else
+ pr_warn("WARNING: CPU: %d PID: %d at %pS\n",
+ raw_smp_processor_id(), current->pid, caller);
if (args)
vprintk(args->fmt, args->args);
@@ -479,20 +485,27 @@ static void warn_slowpath_common(const char *file, int line, void *caller,
}
print_modules();
- dump_stack();
+
+ if (regs)
+ show_regs(regs);
+ else
+ dump_stack();
+
print_oops_end_marker();
+
/* Just a warning, don't kill lockdep. */
add_taint(taint, LOCKDEP_STILL_OK);
}
+#ifdef WANT_WARN_ON_SLOWPATH
void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
{
- struct slowpath_args args;
+ struct warn_args args;
args.fmt = fmt;
va_start(args.args, fmt);
- warn_slowpath_common(file, line, __builtin_return_address(0),
- TAINT_WARN, &args);
+ __warn(file, line, __builtin_return_address(0), TAINT_WARN, NULL,
+ &args);
va_end(args.args);
}
EXPORT_SYMBOL(warn_slowpath_fmt);
@@ -500,20 +513,18 @@ EXPORT_SYMBOL(warn_slowpath_fmt);
void warn_slowpath_fmt_taint(const char *file, int line,
unsigned taint, const char *fmt, ...)
{
- struct slowpath_args args;
+ struct warn_args args;
args.fmt = fmt;
va_start(args.args, fmt);
- warn_slowpath_common(file, line, __builtin_return_address(0),
- taint, &args);
+ __warn(file, line, __builtin_return_address(0), taint, NULL, &args);
va_end(args.args);
}
EXPORT_SYMBOL(warn_slowpath_fmt_taint);
void warn_slowpath_null(const char *file, int line)
{
- warn_slowpath_common(file, line, __builtin_return_address(0),
- TAINT_WARN, NULL);
+ __warn(file, line, __builtin_return_address(0), TAINT_WARN, NULL, NULL);
}
EXPORT_SYMBOL(warn_slowpath_null);
#endif
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index c963ba534a78..bfbf284e4218 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -367,16 +367,20 @@ static int logbuf_has_space(u32 msg_size, bool empty)
static int log_make_free_space(u32 msg_size)
{
- while (log_first_seq < log_next_seq) {
- if (logbuf_has_space(msg_size, false))
- return 0;
+ while (log_first_seq < log_next_seq &&
+ !logbuf_has_space(msg_size, false)) {
/* drop old messages until we have enough contiguous space */
log_first_idx = log_next(log_first_idx);
log_first_seq++;
}
+ if (clear_seq < log_first_seq) {
+ clear_seq = log_first_seq;
+ clear_idx = log_first_idx;
+ }
+
/* sequence numbers are equal, so the log buffer is empty */
- if (logbuf_has_space(msg_size, true))
+ if (logbuf_has_space(msg_size, log_first_seq == log_next_seq))
return 0;
return -ENOMEM;
@@ -854,6 +858,7 @@ void log_buf_kexec_setup(void)
VMCOREINFO_SYMBOL(log_buf);
VMCOREINFO_SYMBOL(log_buf_len);
VMCOREINFO_SYMBOL(log_first_idx);
+ VMCOREINFO_SYMBOL(clear_idx);
VMCOREINFO_SYMBOL(log_next_idx);
/*
* Export struct printk_log size and field offsets. User space tools can
@@ -1216,12 +1221,6 @@ static int syslog_print_all(char __user *buf, int size, bool clear)
u32 idx;
enum log_flags prev;
- if (clear_seq < log_first_seq) {
- /* messages are gone, move to first available one */
- clear_seq = log_first_seq;
- clear_idx = log_first_idx;
- }
-
/*
* Find first record that fits, including all following records,
* into the user-provided buffer for this dump.
@@ -1483,58 +1482,6 @@ static void zap_locks(void)
sema_init(&console_sem, 1);
}
-/*
- * Check if we have any console that is capable of printing while cpu is
- * booting or shutting down. Requires console_sem.
- */
-static int have_callable_console(void)
-{
- struct console *con;
-
- for_each_console(con)
- if (con->flags & CON_ANYTIME)
- return 1;
-
- return 0;
-}
-
-/*
- * Can we actually use the console at this time on this cpu?
- *
- * Console drivers may assume that per-cpu resources have been allocated. So
- * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't
- * call them until this CPU is officially up.
- */
-static inline int can_use_console(unsigned int cpu)
-{
- return cpu_online(cpu) || have_callable_console();
-}
-
-/*
- * Try to get console ownership to actually show the kernel
- * messages from a 'printk'. Return true (and with the
- * console_lock held, and 'console_locked' set) if it
- * is successful, false otherwise.
- */
-static int console_trylock_for_printk(void)
-{
- unsigned int cpu = smp_processor_id();
-
- if (!console_trylock())
- return 0;
- /*
- * If we can't use the console, we need to release the console
- * semaphore by hand to avoid flushing the buffer. We need to hold the
- * console semaphore in order to do this test safely.
- */
- if (!can_use_console(cpu)) {
- console_locked = 0;
- up_console_sem();
- return 0;
- }
- return 1;
-}
-
int printk_delay_msec __read_mostly;
static inline void printk_delay(void)
@@ -1681,7 +1628,6 @@ asmlinkage int vprintk_emit(int facility, int level,
boot_delay_msec(level);
printk_delay();
- /* This stops the holder of console_sem just where we want him */
local_irq_save(flags);
this_cpu = smp_processor_id();
@@ -1705,6 +1651,7 @@ asmlinkage int vprintk_emit(int facility, int level,
}
lockdep_off();
+ /* This stops the holder of console_sem just where we want him */
raw_spin_lock(&logbuf_lock);
logbuf_cpu = this_cpu;
@@ -1810,20 +1757,12 @@ asmlinkage int vprintk_emit(int facility, int level,
if (!in_sched) {
lockdep_off();
/*
- * Disable preemption to avoid being preempted while holding
- * console_sem which would prevent anyone from printing to
- * console
- */
- preempt_disable();
-
- /*
* Try to acquire and then immediately release the console
* semaphore. The release will print out buffers and wake up
* /dev/kmsg and syslog() users.
*/
- if (console_trylock_for_printk())
+ if (console_trylock())
console_unlock();
- preempt_enable();
lockdep_on();
}
@@ -2174,7 +2113,20 @@ int console_trylock(void)
return 0;
}
console_locked = 1;
- console_may_schedule = 0;
+ /*
+ * When PREEMPT_COUNT disabled we can't reliably detect if it's
+ * safe to schedule (e.g. calling printk while holding a spin_lock),
+ * because preempt_disable()/preempt_enable() are just barriers there
+ * and preempt_count() is always 0.
+ *
+ * RCU read sections have a separate preemption counter when
+ * PREEMPT_RCU enabled thus we must take extra care and check
+ * rcu_preempt_depth(), otherwise RCU read sections modify
+ * preempt_count().
+ */
+ console_may_schedule = !oops_in_progress &&
+ preemptible() &&
+ !rcu_preempt_depth();
return 1;
}
EXPORT_SYMBOL(console_trylock);
@@ -2184,6 +2136,34 @@ int is_console_locked(void)
return console_locked;
}
+/*
+ * Check if we have any console that is capable of printing while cpu is
+ * booting or shutting down. Requires console_sem.
+ */
+static int have_callable_console(void)
+{
+ struct console *con;
+
+ for_each_console(con)
+ if ((con->flags & CON_ENABLED) &&
+ (con->flags & CON_ANYTIME))
+ return 1;
+
+ return 0;
+}
+
+/*
+ * Can we actually use the console at this time on this cpu?
+ *
+ * Console drivers may assume that per-cpu resources have been allocated. So
+ * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't
+ * call them until this CPU is officially up.
+ */
+static inline int can_use_console(void)
+{
+ return cpu_online(raw_smp_processor_id()) || have_callable_console();
+}
+
static void console_cont_flush(char *text, size_t size)
{
unsigned long flags;
@@ -2254,9 +2234,21 @@ void console_unlock(void)
do_cond_resched = console_may_schedule;
console_may_schedule = 0;
+again:
+ /*
+ * We released the console_sem lock, so we need to recheck if
+ * cpu is online and (if not) is there at least one CON_ANYTIME
+ * console.
+ */
+ if (!can_use_console()) {
+ console_locked = 0;
+ up_console_sem();
+ return;
+ }
+
/* flush buffered message fragment immediately to console */
console_cont_flush(text, sizeof(text));
-again:
+
for (;;) {
struct printk_log *msg;
size_t ext_len = 0;
diff --git a/kernel/sys.c b/kernel/sys.c
index 78947de6f969..cf8ba545c7d3 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2169,7 +2169,10 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
error = perf_event_task_enable();
break;
case PR_GET_TIMERSLACK:
- error = current->timer_slack_ns;
+ if (current->timer_slack_ns > ULONG_MAX)
+ error = ULONG_MAX;
+ else
+ error = current->timer_slack_ns;
break;
case PR_SET_TIMERSLACK:
if (arg2 <= 0)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index f5102fabef7f..725587f10667 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -126,6 +126,7 @@ static int __maybe_unused two = 2;
static int __maybe_unused four = 4;
static unsigned long one_ul = 1;
static int one_hundred = 100;
+static int one_thousand = 1000;
#ifdef CONFIG_PRINTK
static int ten_thousand = 10000;
#endif
@@ -1404,6 +1405,15 @@ static struct ctl_table vm_table[] = {
.extra1 = &zero,
},
{
+ .procname = "watermark_scale_factor",
+ .data = &watermark_scale_factor,
+ .maxlen = sizeof(watermark_scale_factor),
+ .mode = 0644,
+ .proc_handler = watermark_scale_factor_sysctl_handler,
+ .extra1 = &one,
+ .extra2 = &one_thousand,
+ },
+ {
.procname = "percpu_pagelist_fraction",
.data = &percpu_pagelist_fraction,
.maxlen = sizeof(percpu_pagelist_fraction),
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index fa909f9fd559..fa0b983290cf 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -515,7 +515,7 @@ static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base)
/*
* High resolution timer enabled ?
*/
-static int hrtimer_hres_enabled __read_mostly = 1;
+static bool hrtimer_hres_enabled __read_mostly = true;
unsigned int hrtimer_resolution __read_mostly = LOW_RES_NSEC;
EXPORT_SYMBOL_GPL(hrtimer_resolution);
@@ -524,13 +524,7 @@ EXPORT_SYMBOL_GPL(hrtimer_resolution);
*/
static int __init setup_hrtimer_hres(char *str)
{
- if (!strcmp(str, "off"))
- hrtimer_hres_enabled = 0;
- else if (!strcmp(str, "on"))
- hrtimer_hres_enabled = 1;
- else
- return 0;
- return 1;
+ return (kstrtobool(str, &hrtimer_hres_enabled) == 0);
}
__setup("highres=", setup_hrtimer_hres);
@@ -979,7 +973,7 @@ static inline ktime_t hrtimer_update_lowres(struct hrtimer *timer, ktime_t tim,
* relative (HRTIMER_MODE_REL)
*/
void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
- unsigned long delta_ns, const enum hrtimer_mode mode)
+ u64 delta_ns, const enum hrtimer_mode mode)
{
struct hrtimer_clock_base *base, *new_base;
unsigned long flags;
@@ -1548,7 +1542,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp,
struct restart_block *restart;
struct hrtimer_sleeper t;
int ret = 0;
- unsigned long slack;
+ u64 slack;
slack = current->timer_slack_ns;
if (dl_task(current) || rt_task(current))
@@ -1724,7 +1718,7 @@ void __init hrtimers_init(void)
* @clock: timer clock, CLOCK_MONOTONIC or CLOCK_REALTIME
*/
int __sched
-schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta,
+schedule_hrtimeout_range_clock(ktime_t *expires, u64 delta,
const enum hrtimer_mode mode, int clock)
{
struct hrtimer_sleeper t;
@@ -1792,7 +1786,7 @@ schedule_hrtimeout_range_clock(ktime_t *expires, unsigned long delta,
*
* Returns 0 when the timer has expired otherwise -EINTR
*/
-int __sched schedule_hrtimeout_range(ktime_t *expires, unsigned long delta,
+int __sched schedule_hrtimeout_range(ktime_t *expires, u64 delta,
const enum hrtimer_mode mode)
{
return schedule_hrtimeout_range_clock(expires, delta, mode,
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 969e6704c3c9..195fe7d2caad 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -486,20 +486,14 @@ void __init tick_nohz_init(void)
/*
* NO HZ enabled ?
*/
-int tick_nohz_enabled __read_mostly = 1;
+bool tick_nohz_enabled __read_mostly = true;
unsigned long tick_nohz_active __read_mostly;
/*
* Enable / Disable tickless mode
*/
static int __init setup_tick_nohz(char *str)
{
- if (!strcmp(str, "off"))
- tick_nohz_enabled = 0;
- else if (!strcmp(str, "on"))
- tick_nohz_enabled = 1;
- else
- return 0;
- return 1;
+ return (kstrtobool(str, &tick_nohz_enabled) == 0);
}
__setup("nohz=", setup_tick_nohz);
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index bbc5d1114583..d1798fa0c743 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1698,10 +1698,10 @@ EXPORT_SYMBOL(msleep_interruptible);
static void __sched do_usleep_range(unsigned long min, unsigned long max)
{
ktime_t kmin;
- unsigned long delta;
+ u64 delta;
kmin = ktime_set(0, min * NSEC_PER_USEC);
- delta = (max - min) * NSEC_PER_USEC;
+ delta = (u64)(max - min) * NSEC_PER_USEC;
schedule_hrtimeout_range(&kmin, delta, HRTIMER_MODE_REL);
}
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index b3ace6ebbba3..9acb29f280ec 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -923,6 +923,9 @@ static int proc_watchdog_common(int which, struct ctl_table *table, int write,
* both lockup detectors are disabled if proc_watchdog_update()
* returns an error.
*/
+ if (old == new)
+ goto out;
+
err = proc_watchdog_update();
}
out:
@@ -967,7 +970,7 @@ int proc_soft_watchdog(struct ctl_table *table, int write,
int proc_watchdog_thresh(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
- int err, old;
+ int err, old, new;
get_online_cpus();
mutex_lock(&watchdog_proc_mutex);
@@ -987,6 +990,10 @@ int proc_watchdog_thresh(struct ctl_table *table, int write,
/*
* Update the sample period. Restore on failure.
*/
+ new = ACCESS_ONCE(watchdog_thresh);
+ if (old == new)
+ goto out;
+
set_sample_period();
err = proc_watchdog_update();
if (err) {