From fa93384f40deeb294fd29f2fdcadbd0ebc2dedf1 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 23 May 2014 13:20:42 +0300 Subject: sched: Fix signedness bug in yield_to() yield_to() is supposed to return -ESRCH if there is no task to yield to, but because the type is bool that is the same as returning true. The only place I see which cares is kvm_vcpu_on_spin(). Signed-off-by: Dan Carpenter Reviewed-by: Raghavendra Signed-off-by: Peter Zijlstra Cc: Gleb Natapov Cc: Linus Torvalds Cc: Paolo Bonzini Cc: kvm@vger.kernel.org Link: http://lkml.kernel.org/r/20140523102042.GA7267@mwanda Signed-off-by: Ingo Molnar --- include/linux/sched.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 0f91d00efd87..6790c3b42072 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2180,7 +2180,7 @@ static inline void sched_autogroup_fork(struct signal_struct *sig) { } static inline void sched_autogroup_exit(struct signal_struct *sig) { } #endif -extern bool yield_to(struct task_struct *p, bool preempt); +extern int yield_to(struct task_struct *p, bool preempt); extern void set_user_nice(struct task_struct *p, long nice); extern int task_prio(const struct task_struct *p); /** -- cgit v1.2.3 From 63b2ca30bdb3dbf60bc7ac5f46713c0d32308261 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Mon, 26 May 2014 18:19:37 -0400 Subject: sched: Let 'struct sched_group_power' care about CPU capacity It is better not to think about compute capacity as being equivalent to "CPU power". The upcoming "power aware" scheduler work may create confusion with the notion of energy consumption if "power" is used too liberally. Since struct sched_group_power is really about compute capacity of sched groups, let's rename it to struct sched_group_capacity. Similarly sgp becomes sgc. Related variables and functions dealing with groups are also adjusted accordingly. Signed-off-by: Nicolas Pitre Signed-off-by: Peter Zijlstra Cc: Vincent Guittot Cc: Daniel Lezcano Cc: Morten Rasmussen Cc: "Rafael J. Wysocki" Cc: linaro-kernel@lists.linaro.org Cc: Linus Torvalds Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/n/tip-5yeix833vvgf2uyj5o36hpu9@git.kernel.org Signed-off-by: Ingo Molnar --- include/linux/sched.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 6790c3b42072..a96f03598c61 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1013,7 +1013,7 @@ typedef const int (*sched_domain_flags_f)(void); struct sd_data { struct sched_domain **__percpu sd; struct sched_group **__percpu sg; - struct sched_group_power **__percpu sgp; + struct sched_group_capacity **__percpu sgc; }; struct sched_domain_topology_level { -- cgit v1.2.3 From ca8ce3d0b144c318a5a9ce99649053e9029061ea Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Mon, 26 May 2014 18:19:39 -0400 Subject: sched: Final power vs. capacity cleanups It is better not to think about compute capacity as being equivalent to "CPU power". The upcoming "power aware" scheduler work may create confusion with the notion of energy consumption if "power" is used too liberally. This contains the architecture visible changes. Incidentally, only ARM takes advantage of the available pow^H^H^Hcapacity scaling hooks and therefore those changes outside kernel/sched/ are confined to one ARM specific file. The default arch_scale_smt_power() hook is not overridden by anyone. Replacements are as follows: arch_scale_freq_power --> arch_scale_freq_capacity arch_scale_smt_power --> arch_scale_smt_capacity SCHED_POWER_SCALE --> SCHED_CAPACITY_SCALE SCHED_POWER_SHIFT --> SCHED_CAPACITY_SHIFT The local usage of "power" in arch/arm/kernel/topology.c is also changed to "capacity" as appropriate. Signed-off-by: Nicolas Pitre Signed-off-by: Peter Zijlstra Cc: Vincent Guittot Cc: Daniel Lezcano Cc: Morten Rasmussen Cc: "Rafael J. Wysocki" Cc: linaro-kernel@lists.linaro.org Cc: Arnd Bergmann Cc: Dietmar Eggemann Cc: Grant Likely Cc: Linus Torvalds Cc: Mark Brown Cc: Rob Herring Cc: Russell King Cc: Sudeep KarkadaNagesha Cc: Vincent Guittot Cc: devicetree@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/n/tip-48zba9qbznvglwelgq2cfygh@git.kernel.org Signed-off-by: Ingo Molnar --- include/linux/sched.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index a96f03598c61..322110affe63 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -854,10 +854,10 @@ enum cpu_idle_type { }; /* - * Increase resolution of cpu_power calculations + * Increase resolution of cpu_capacity calculations */ -#define SCHED_POWER_SHIFT 10 -#define SCHED_POWER_SCALE (1L << SCHED_POWER_SHIFT) +#define SCHED_CAPACITY_SHIFT 10 +#define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) /* * sched-domains (multiprocessor balancing) declarations: -- cgit v1.2.3 From 5d4dfddd4f02b028d6ddaaa04d75d3b0cad1c9ae Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Tue, 27 May 2014 13:50:41 -0400 Subject: sched: Rename capacity related flags It is better not to think about compute capacity as being equivalent to "CPU power". The upcoming "power aware" scheduler work may create confusion with the notion of energy consumption if "power" is used too liberally. Let's rename the following feature flags since they do relate to capacity: SD_SHARE_CPUPOWER -> SD_SHARE_CPUCAPACITY ARCH_POWER -> ARCH_CAPACITY NONTASK_POWER -> NONTASK_CAPACITY Signed-off-by: Nicolas Pitre Signed-off-by: Peter Zijlstra Cc: Vincent Guittot Cc: Daniel Lezcano Cc: Morten Rasmussen Cc: "Rafael J. Wysocki" Cc: linaro-kernel@lists.linaro.org Cc: Andy Fleming Cc: Anton Blanchard Cc: Benjamin Herrenschmidt Cc: Grant Likely Cc: Linus Torvalds Cc: Michael Ellerman Cc: Paul Gortmaker Cc: Paul Mackerras Cc: Preeti U Murthy Cc: Rob Herring Cc: Srivatsa S. Bhat Cc: Toshi Kani Cc: Vasant Hegde Cc: Vincent Guittot Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/n/tip-e93lpnxb87owfievqatey6b5@git.kernel.org Signed-off-by: Ingo Molnar --- include/linux/sched.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 322110affe63..ce93768a3312 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -869,7 +869,7 @@ enum cpu_idle_type { #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */ #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */ #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */ -#define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */ +#define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu power */ #define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */ #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */ #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */ @@ -881,7 +881,7 @@ enum cpu_idle_type { #ifdef CONFIG_SCHED_SMT static inline const int cpu_smt_flags(void) { - return SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES; + return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES; } #endif -- cgit v1.2.3 From 82b897782d10fcc4930c9d4a15b175348fdd2871 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Wed, 28 May 2014 11:45:04 +0300 Subject: perf: Differentiate exec() and non-exec() comm events perf tools like 'perf report' can aggregate samples by comm strings, which generally works. However, there are other potential use-cases. For example, to pair up 'calls' with 'returns' accurately (from branch events like Intel BTS) it is necessary to identify whether the process has exec'd. Although a comm event is generated when an 'exec' happens it is also generated whenever the comm string is changed on a whim (e.g. by prctl PR_SET_NAME). This patch adds a flag to the comm event to differentiate one case from the other. In order to determine whether the kernel supports the new flag, a selection bit named 'exec' is added to struct perf_event_attr. The bit does nothing but will cause perf_event_open() to fail if the bit is set on kernels that do not have it defined. Signed-off-by: Adrian Hunter Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/537D9EBE.7030806@intel.com Cc: Paul Mackerras Cc: Dave Jones Cc: Arnaldo Carvalho de Melo Cc: David Ahern Cc: Jiri Olsa Cc: Alexander Viro Cc: Linus Torvalds Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- include/linux/sched.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 221b2bde3723..ad86e1d7dbc2 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -2379,7 +2379,11 @@ extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, i struct task_struct *fork_idle(int); extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); -extern void set_task_comm(struct task_struct *tsk, const char *from); +extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); +static inline void set_task_comm(struct task_struct *tsk, const char *from) +{ + __set_task_comm(tsk, from, false); +} extern char *get_task_comm(char *to, struct task_struct *tsk); #ifdef CONFIG_SMP -- cgit v1.2.3