From a0d76247e07abd14968adc4486aaa8e270e9c209 Mon Sep 17 00:00:00 2001 From: Robert Richter Date: Fri, 11 Feb 2011 17:31:44 +0100 Subject: oprofile, s390: Rework hwsampler implementation This patch is a rework of the hwsampler oprofile implementation that has been applied recently. Now there are less non-architectural changes. The only changes are: * introduction of oprofile_add_ext_hw_sample(), and * removal of section attributes of oprofile_timer_init/_exit(). To setup hwsampler for oprofile we need to modify start()/stop() callbacks and additional hwsampler control files in oprofilefs. We do not reinitialize the timer or hwsampler mode by restarting calling init/exit() anymore, instead hwsampler_running is used to switch the mode directly in oprofile_hwsampler_start/_stop(). For locking reasons there is also hwsampler_file that reflects the value in oprofilefs. The overall diffstat of the oprofile s390 hwsampler implemenation shows the low impact to non-architectural code: arch/Kconfig | 3 + arch/s390/Kconfig | 1 + arch/s390/oprofile/Makefile | 2 +- arch/s390/oprofile/hwsampler.c | 1256 ++++++++++++++++++++++++++++++++++ arch/s390/oprofile/hwsampler.h | 113 +++ arch/s390/oprofile/hwsampler_files.c | 162 +++++ arch/s390/oprofile/init.c | 6 +- drivers/oprofile/cpu_buffer.c | 24 +- drivers/oprofile/timer_int.c | 4 +- include/linux/oprofile.h | 7 + 10 files changed, 1567 insertions(+), 11 deletions(-) Acked-by: Heiko Carstens Signed-off-by: Robert Richter --- arch/s390/oprofile/hwsampler_files.c | 60 +++++++++++++++++++++++------------- arch/s390/oprofile/init.c | 1 - drivers/oprofile/oprof.c | 32 ------------------- drivers/oprofile/oprof.h | 2 -- drivers/oprofile/timer_int.c | 15 ++------- include/linux/oprofile.h | 21 ------------- 6 files changed, 41 insertions(+), 90 deletions(-) diff --git a/arch/s390/oprofile/hwsampler_files.c b/arch/s390/oprofile/hwsampler_files.c index 493f7cc4e861..2e1da2449ba9 100644 --- a/arch/s390/oprofile/hwsampler_files.c +++ b/arch/s390/oprofile/hwsampler_files.c @@ -8,6 +8,7 @@ #include #include +#include "../../../drivers/oprofile/oprof.h" #include "hwsampler.h" #define DEFAULT_INTERVAL 4096 @@ -22,12 +23,20 @@ static unsigned long oprofile_max_interval; static unsigned long oprofile_sdbt_blocks = DEFAULT_SDBT_BLOCKS; static unsigned long oprofile_sdb_blocks = DEFAULT_SDB_BLOCKS; -static unsigned long oprofile_hwsampler; +static int hwsampler_file; +static int hwsampler_running; /* start_mutex must be held to change */ + +static struct oprofile_operations timer_ops; static int oprofile_hwsampler_start(void) { int retval; + hwsampler_running = hwsampler_file; + + if (!hwsampler_running) + return timer_ops.start(); + retval = hwsampler_allocate(oprofile_sdbt_blocks, oprofile_sdb_blocks); if (retval) return retval; @@ -41,25 +50,20 @@ static int oprofile_hwsampler_start(void) static void oprofile_hwsampler_stop(void) { + if (!hwsampler_running) { + timer_ops.stop(); + return; + } + hwsampler_stop_all(); hwsampler_deallocate(); return; } -int oprofile_arch_set_hwsampler(struct oprofile_operations *ops) -{ - printk(KERN_INFO "oprofile: using hardware sampling\n"); - ops->start = oprofile_hwsampler_start; - ops->stop = oprofile_hwsampler_stop; - ops->cpu_type = "timer"; - - return 0; -} - static ssize_t hwsampler_read(struct file *file, char __user *buf, size_t count, loff_t *offset) { - return oprofilefs_ulong_to_user(oprofile_hwsampler, buf, count, offset); + return oprofilefs_ulong_to_user(hwsampler_file, buf, count, offset); } static ssize_t hwsampler_write(struct file *file, char const __user *buf, @@ -75,15 +79,16 @@ static ssize_t hwsampler_write(struct file *file, char const __user *buf, if (retval) return retval; - if (oprofile_hwsampler == val) - return -EINVAL; - - retval = oprofile_set_hwsampler(val); + if (oprofile_started) + /* + * save to do without locking as we set + * hwsampler_running in start() when start_mutex is + * held + */ + return -EBUSY; - if (retval) - return retval; + hwsampler_file = val; - oprofile_hwsampler = val; return count; } @@ -98,7 +103,7 @@ static int oprofile_create_hwsampling_files(struct super_block *sb, struct dentry *hw_dir; /* reinitialize default values */ - oprofile_hwsampler = 1; + hwsampler_file = 1; hw_dir = oprofilefs_mkdir(sb, root, "hwsampling"); if (!hw_dir) @@ -125,7 +130,6 @@ int oprofile_hwsampler_init(struct oprofile_operations* ops) /* * create hwsampler files only if hwsampler_setup() succeeds. */ - ops->create_files = oprofile_create_hwsampling_files; oprofile_min_interval = hwsampler_query_min_interval(); if (oprofile_min_interval < 0) { oprofile_min_interval = 0; @@ -136,11 +140,23 @@ int oprofile_hwsampler_init(struct oprofile_operations* ops) oprofile_max_interval = 0; return -ENODEV; } - oprofile_arch_set_hwsampler(ops); + + if (oprofile_timer_init(ops)) + return -ENODEV; + + printk(KERN_INFO "oprofile: using hardware sampling\n"); + + memcpy(&timer_ops, ops, sizeof(timer_ops)); + + ops->start = oprofile_hwsampler_start; + ops->stop = oprofile_hwsampler_stop; + ops->create_files = oprofile_create_hwsampling_files; + return 0; } void oprofile_hwsampler_exit(void) { + oprofile_timer_exit(); hwsampler_shutdown(); } diff --git a/arch/s390/oprofile/init.c b/arch/s390/oprofile/init.c index f6b3f724f590..059b44b9f171 100644 --- a/arch/s390/oprofile/init.c +++ b/arch/s390/oprofile/init.c @@ -11,7 +11,6 @@ #include #include #include -#include extern int oprofile_hwsampler_init(struct oprofile_operations* ops); extern void oprofile_hwsampler_exit(void); diff --git a/drivers/oprofile/oprof.c b/drivers/oprofile/oprof.c index 43b01daa91e1..f9bda64fcd1b 100644 --- a/drivers/oprofile/oprof.c +++ b/drivers/oprofile/oprof.c @@ -239,38 +239,6 @@ int oprofile_set_ulong(unsigned long *addr, unsigned long val) return err; } -#ifdef CONFIG_HAVE_HWSAMPLER -int oprofile_set_hwsampler(unsigned long val) -{ - int err = 0; - - mutex_lock(&start_mutex); - - if (oprofile_started) { - err = -EBUSY; - goto out; - } - - switch (val) { - case 1: - /* Switch to hardware sampling. */ - __oprofile_timer_exit(); - err = oprofile_arch_set_hwsampler(&oprofile_ops); - break; - case 0: - printk(KERN_INFO "oprofile: using timer interrupt.\n"); - err = __oprofile_timer_init(&oprofile_ops); - break; - default: - err = -EINVAL; - } - -out: - mutex_unlock(&start_mutex); - return err; -} -#endif /* CONFIG_HAVE_HWSAMPLER */ - static int __init oprofile_init(void) { int err; diff --git a/drivers/oprofile/oprof.h b/drivers/oprofile/oprof.h index 5a6ceb1954a2..177b73de5e5f 100644 --- a/drivers/oprofile/oprof.h +++ b/drivers/oprofile/oprof.h @@ -35,9 +35,7 @@ struct dentry; void oprofile_create_files(struct super_block *sb, struct dentry *root); int oprofile_timer_init(struct oprofile_operations *ops); -int __oprofile_timer_init(struct oprofile_operations *ops); void oprofile_timer_exit(void); -void __oprofile_timer_exit(void); int oprofile_set_ulong(unsigned long *addr, unsigned long val); int oprofile_set_timeout(unsigned long time); diff --git a/drivers/oprofile/timer_int.c b/drivers/oprofile/timer_int.c index 0099a458fd37..3ef44624f510 100644 --- a/drivers/oprofile/timer_int.c +++ b/drivers/oprofile/timer_int.c @@ -97,13 +97,14 @@ static struct notifier_block __refdata oprofile_cpu_notifier = { .notifier_call = oprofile_cpu_notify, }; -int __oprofile_timer_init(struct oprofile_operations *ops) +int oprofile_timer_init(struct oprofile_operations *ops) { int rc; rc = register_hotcpu_notifier(&oprofile_cpu_notifier); if (rc) return rc; + ops->create_files = NULL; ops->setup = NULL; ops->shutdown = NULL; ops->start = oprofile_hrtimer_start; @@ -112,17 +113,7 @@ int __oprofile_timer_init(struct oprofile_operations *ops) return 0; } -int __init oprofile_timer_init(struct oprofile_operations *ops) -{ - return __oprofile_timer_init(ops); -} - -void __oprofile_timer_exit(void) +void oprofile_timer_exit(void) { unregister_hotcpu_notifier(&oprofile_cpu_notifier); } - -void __exit oprofile_timer_exit(void) -{ - __oprofile_timer_exit(); -} diff --git a/include/linux/oprofile.h b/include/linux/oprofile.h index b517d869e1ad..7f5cfd3b37dd 100644 --- a/include/linux/oprofile.h +++ b/include/linux/oprofile.h @@ -91,27 +91,6 @@ int oprofile_arch_init(struct oprofile_operations * ops); */ void oprofile_arch_exit(void); -#ifdef CONFIG_HAVE_HWSAMPLER -/** - * setup hardware sampler for oprofiling. - */ - -int oprofile_set_hwsampler(unsigned long); - -/** - * hardware sampler module initialization for the s390 arch - */ - -int oprofile_arch_set_hwsampler(struct oprofile_operations *ops); - -/** - * Add an s390 hardware sample. - */ -void oprofile_add_ext_hw_sample(unsigned long pc, struct pt_regs * const regs, - unsigned long event, int is_kernel, - struct task_struct *task); -#endif /* CONFIG_HAVE_HWSAMPLER */ - /** * Add a sample. This may be called from any context. */ -- cgit v1.2.3-59-g8ed1b