From d8e8ed95cda1dfd6813588333d36552935eba4a1 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Thu, 15 Dec 2011 13:43:24 +1030 Subject: rcu: Make rcutorture bool parameters really bool (core code) module_param(bool) used to counter-intuitively take an int. In fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy trick. It's time to remove the int/unsigned int option. For this version it'll simply give a warning, but it'll break next kernel version. This commit makes this change to rcutorture. Signed-off-by: Rusty Russell Signed-off-by: Paul E. McKenney --- kernel/rcutorture.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 88f17b8a3b1d..e29edc374cec 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -56,8 +56,8 @@ static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */ static int nfakewriters = 4; /* # fake writer threads */ static int stat_interval; /* Interval between stats, in seconds. */ /* Defaults to "only at end of test". */ -static int verbose; /* Print more debug info. */ -static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ +static bool verbose; /* Print more debug info. */ +static bool test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/ static int stutter = 5; /* Start/stop testing interval (in sec) */ static int irqreader = 1; /* RCU readers from irq (timers). */ -- cgit v1.2.3 From 4410030646be072b82ec1892ad5cc7d91af384d8 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Tue, 27 Dec 2011 15:04:26 +0100 Subject: rcu: Add missing __cpuinit annotation in rcutorture code "rcu: Add rcutorture CPU-hotplug capability" adds cpu hotplug operations to the rcutorture code but produces a false positive warning about section mismatches: WARNING: vmlinux.o(.text+0x1e420c): Section mismatch in reference from the function rcu_torture_onoff() to the function .cpuinit.text:cpu_up() The function rcu_torture_onoff() references the function __cpuinit cpu_up(). This is often because rcu_torture_onoff lacks a __cpuinit annotation or the annotation of cpu_up is wrong. This commit therefore adds a __cpuinit annotation so the warning goes away. Signed-off-by: Heiko Carstens Signed-off-by: Paul E. McKenney --- kernel/rcutorture.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index e29edc374cec..a58ac285fc69 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -1399,7 +1399,7 @@ rcu_torture_shutdown(void *arg) * Execute random CPU-hotplug operations at the interval specified * by the onoff_interval. */ -static int +static int __cpuinit rcu_torture_onoff(void *arg) { int cpu; @@ -1447,7 +1447,7 @@ rcu_torture_onoff(void *arg) return 0; } -static int +static int __cpuinit rcu_torture_onoff_init(void) { if (onoff_interval <= 0) -- cgit v1.2.3 From fd45c15f13e754f3c106427e857310f3e0813951 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Fri, 20 Jan 2012 10:12:45 +0900 Subject: perf: Don't call release_callchain_buffers() if allocation fails When alloc_callchain_buffers() fails, it frees all of entries before return. In addition, calling the release_callchain_buffers() will cause a NULL pointer dereference since callchain_cpu_entries is not set. Signed-off-by: Namhyung Kim Acked-by: Frederic Weisbecker Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Link: http://lkml.kernel.org/r/1327021966-27688-1-git-send-email-namhyung.kim@lge.com Signed-off-by: Ingo Molnar --- kernel/events/callchain.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'kernel') diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 057e24b665cf..6581a040f399 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -115,8 +115,6 @@ int get_callchain_buffers(void) } err = alloc_callchain_buffers(); - if (err) - release_callchain_buffers(); exit: mutex_unlock(&callchain_mutex); -- cgit v1.2.3 From 46cd6a7f680d14f6f80ede9f04aeb70fa83bd266 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Fri, 20 Jan 2012 10:12:46 +0900 Subject: perf: Call perf_cgroup_event_time() directly The perf_event_time() will call perf_cgroup_event_time() if @event is a cgroup event. Just do it directly and avoid the extra check.. Signed-off-by: Namhyung Kim Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Link: http://lkml.kernel.org/r/1327021966-27688-2-git-send-email-namhyung.kim@lge.com Signed-off-by: Ingo Molnar --- kernel/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/events/core.c b/kernel/events/core.c index a8f4ac001a00..32b48c889711 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -815,7 +815,7 @@ static void update_event_times(struct perf_event *event) * here. */ if (is_cgroup_event(event)) - run_end = perf_event_time(event); + run_end = perf_cgroup_event_time(event); else if (ctx->is_active) run_end = ctx->time; else -- cgit v1.2.3 From 181e9bdef37bfcaa41f3ab6c948a2a0d60a268b5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 29 Jan 2012 20:35:52 +0100 Subject: PM / Hibernate: Fix s2disk regression related to freezing workqueues Commit 2aede851ddf08666f68ffc17be446420e9d2a056 PM / Hibernate: Freeze kernel threads after preallocating memory introduced a mechanism by which kernel threads were frozen after the preallocation of hibernate image memory to avoid problems with frozen kernel threads not responding to memory freeing requests. However, it overlooked the s2disk code path in which the SNAPSHOT_CREATE_IMAGE ioctl was run directly after SNAPSHOT_FREE, which caused freeze_workqueues_begin() to BUG(), because it saw that worqueues had been already frozen. Although in principle this issue might be addressed by removing the relevant BUG_ON() from freeze_workqueues_begin(), that would reintroduce the very problem that commit 2aede851ddf08666f68ffc17be4 attempted to avoid into that particular code path. For this reason, to fix the issue at hand, introduce thaw_kernel_threads() and make the SNAPSHOT_FREE ioctl execute it. Special thanks to Srivatsa S. Bhat for detailed analysis of the problem. Reported-and-tested-by: Jiri Slaby Signed-off-by: Rafael J. Wysocki Acked-by: Srivatsa S. Bhat Cc: stable@kernel.org --- kernel/power/process.c | 19 +++++++++++++++++++ kernel/power/user.c | 9 +++++++++ 2 files changed, 28 insertions(+) (limited to 'kernel') diff --git a/kernel/power/process.c b/kernel/power/process.c index 77274c9ba2f1..eeca00311f39 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -188,3 +188,22 @@ void thaw_processes(void) printk("done.\n"); } +void thaw_kernel_threads(void) +{ + struct task_struct *g, *p; + + pm_nosig_freezing = false; + printk("Restarting kernel threads ... "); + + thaw_workqueues(); + + read_lock(&tasklist_lock); + do_each_thread(g, p) { + if (p->flags & (PF_KTHREAD | PF_WQ_WORKER)) + __thaw_task(p); + } while_each_thread(g, p); + read_unlock(&tasklist_lock); + + schedule(); + printk("done.\n"); +} diff --git a/kernel/power/user.c b/kernel/power/user.c index 6b1ab7a88522..e5a21a857302 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -274,6 +274,15 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, swsusp_free(); memset(&data->handle, 0, sizeof(struct snapshot_handle)); data->ready = 0; + /* + * It is necessary to thaw kernel threads here, because + * SNAPSHOT_CREATE_IMAGE may be invoked directly after + * SNAPSHOT_FREE. In that case, if kernel threads were not + * thawed, the preallocation of memory carried out by + * hibernation_snapshot() might run into problems (i.e. it + * might fail or even deadlock). + */ + thaw_kernel_threads(); break; case SNAPSHOT_PREF_IMAGE_SIZE: -- cgit v1.2.3