From 8d7dc9283f399e1fda4e48a1c453f689326d9396 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 14 Apr 2015 19:33:59 -0700 Subject: rcu: Control grace-period delays directly from value In a misguided attempt to avoid an #ifdef, the use of the gp_init_delay module parameter was conditioned on the corresponding RCU_TORTURE_TEST_SLOW_INIT Kconfig variable, using IS_ENABLED() at the point of use in the code. This meant that the compiler always saw the delay, which meant that RCU_TORTURE_TEST_SLOW_INIT_DELAY had to be unconditionally defined. This in turn caused "make oldconfig" to ask pointless questions about the value of RCU_TORTURE_TEST_SLOW_INIT_DELAY in cases where it was not even used. This commit avoids these pointless questions by defining gp_init_delay under #ifdef. In one branch, gp_init_delay is initialized to RCU_TORTURE_TEST_SLOW_INIT_DELAY and is also a module parameter (thus allowing boot-time modification), and in the other branch gp_init_delay is a const variable initialized by default to zero. This approach also simplifies the code at the delay point by eliminating the IS_DEFINED(). Because gp_init_delay is constant zero in the no-delay case intended for production use, the "gp_init_delay > 0" check causes the delay to become dead code, as desired in this case. In addition, this commit replaces magic constant "10" with the preprocessor variable PER_RCU_NODE_PERIOD, which controls the number of grace periods that are allowed to elapse at full speed before a delay is inserted. Reported-by: Linus Torvalds Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) (limited to 'kernel') diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 233165da782f..8cf7304b2867 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -162,11 +162,14 @@ static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp); static int kthread_prio = CONFIG_RCU_KTHREAD_PRIO; module_param(kthread_prio, int, 0644); -/* Delay in jiffies for grace-period initialization delays. */ -static int gp_init_delay = IS_ENABLED(CONFIG_RCU_TORTURE_TEST_SLOW_INIT) - ? CONFIG_RCU_TORTURE_TEST_SLOW_INIT_DELAY - : 0; +/* Delay in jiffies for grace-period initialization delays, debug only. */ +#ifdef CONFIG_RCU_TORTURE_TEST_SLOW_INIT +static int gp_init_delay = CONFIG_RCU_TORTURE_TEST_SLOW_INIT_DELAY; module_param(gp_init_delay, int, 0644); +#else /* #ifdef CONFIG_RCU_TORTURE_TEST_SLOW_INIT */ +static const int gp_init_delay; +#endif /* #else #ifdef CONFIG_RCU_TORTURE_TEST_SLOW_INIT */ +#define PER_RCU_NODE_PERIOD 10 /* Number of grace periods between delays. */ /* * Track the rcutorture test sequence number and the update version @@ -1843,9 +1846,8 @@ static int rcu_gp_init(struct rcu_state *rsp) raw_spin_unlock_irq(&rnp->lock); cond_resched_rcu_qs(); ACCESS_ONCE(rsp->gp_activity) = jiffies; - if (IS_ENABLED(CONFIG_RCU_TORTURE_TEST_SLOW_INIT) && - gp_init_delay > 0 && - !(rsp->gpnum % (rcu_num_nodes * 10))) + if (gp_init_delay > 0 && + !(rsp->gpnum % (rcu_num_nodes * PER_RCU_NODE_PERIOD))) schedule_timeout_uninterruptible(gp_init_delay); } -- cgit v1.2.3 From 10a50f1ab5f06c9a3ee5ece3ec52e607ed53c79f Mon Sep 17 00:00:00 2001 From: Roger Quadros Date: Wed, 15 Apr 2015 11:14:11 +0300 Subject: genirq: Set IRQCHIP_SKIP_SET_WAKE flag for dummy_irq_chip Without this system suspend is broken on systems that have drivers calling enable/disable_irq_wake() for interrupts based off the dummy irq hook. (e.g. drivers/gpio/gpio-pcf857x.c) Signed-off-by: Roger Quadros Cc: Cc: Cc: Cc: Gregory Clement Link: http://lkml.kernel.org/r/552E1DD3.4040106@ti.com Signed-off-by: Thomas Gleixner --- kernel/irq/dummychip.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel') diff --git a/kernel/irq/dummychip.c b/kernel/irq/dummychip.c index 988dc58e8847..2feb6feca0cc 100644 --- a/kernel/irq/dummychip.c +++ b/kernel/irq/dummychip.c @@ -57,5 +57,6 @@ struct irq_chip dummy_irq_chip = { .irq_ack = noop, .irq_mask = noop, .irq_unmask = noop, + .flags = IRQCHIP_SKIP_SET_WAKE, }; EXPORT_SYMBOL_GPL(dummy_irq_chip); -- cgit v1.2.3 From 149aabcc44e3e2c1f8fe4f0832be53d2db55b598 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Fri, 10 Apr 2015 12:56:41 +0530 Subject: clockevents: Shutdown detached clockevent device A clockevent device is marked DETACHED when it is replaced by another clockevent device. The device is shutdown properly for drivers that implement legacy ->set_mode() callback, as we call ->set_mode() for CLOCK_EVT_MODE_UNUSED as well. But for the new per-state callback interface, we skip shutting down the device, as we thought its an internal state change. That wasn't correct. The effect is that the device is left programmed in oneshot or periodic mode. Fall-back to 'case CLOCK_EVT_STATE_SHUTDOWN', to shutdown the device. Fixes: bd624d75db21 "clockevents: Introduce mode specific callbacks" Reported-by: Daniel Lezcano Signed-off-by: Viresh Kumar Cc: linaro-kernel@lists.linaro.org Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/eef0a91c51b74d4e52c8e5a95eca27b5a0563f07.1428650683.git.viresh.kumar@linaro.org Signed-off-by: Thomas Gleixner --- kernel/time/clockevents.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'kernel') diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 25d942d1da27..629be4e21e96 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -117,11 +117,7 @@ static int __clockevents_set_state(struct clock_event_device *dev, /* Transition with new state-specific callbacks */ switch (state) { case CLOCK_EVT_STATE_DETACHED: - /* - * This is an internal state, which is guaranteed to go from - * SHUTDOWN to DETACHED. No driver interaction required. - */ - return 0; + /* The clockevent device is getting replaced. Shut it down. */ case CLOCK_EVT_STATE_SHUTDOWN: return dev->set_state_shutdown(dev); -- cgit v1.2.3 From ac01ce1410fc2c7b5f3af5e9c972e6a412eee54f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Wed, 29 Apr 2015 16:18:46 +0100 Subject: tracing: Make ftrace_print_array_seq compute buf_len MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The only caller to this function (__print_array) was getting it wrong by passing the array length instead of buffer length. As the element size was already being passed for other reasons it seems reasonable to push the calculation of buffer length into the function. Link: http://lkml.kernel.org/r/1430320727-14582-1-git-send-email-alex.bennee@linaro.org Signed-off-by: Alex Bennée Signed-off-by: Steven Rostedt --- kernel/trace/trace_output.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 692bf7184c8c..25a086bcb700 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -178,12 +178,13 @@ ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len) EXPORT_SYMBOL(ftrace_print_hex_seq); const char * -ftrace_print_array_seq(struct trace_seq *p, const void *buf, int buf_len, +ftrace_print_array_seq(struct trace_seq *p, const void *buf, int count, size_t el_size) { const char *ret = trace_seq_buffer_ptr(p); const char *prefix = ""; void *ptr = (void *)buf; + size_t buf_len = count * el_size; trace_seq_putc(p, '{'); -- cgit v1.2.3