From bd7dc46f770d317ada1348294ff1f319243b803b Mon Sep 17 00:00:00 2001 From: Robert Richter Date: Tue, 6 Jan 2009 03:56:50 +0100 Subject: oprofile: add op_cpu_buffer_get_data() This function provides access to attached data of a sample. It returns the size of data including the current value. Also, op_cpu_buffer_get_size() is available to check if there is data attached. Signed-off-by: Robert Richter --- drivers/oprofile/buffer_sync.c | 6 ++++-- drivers/oprofile/cpu_buffer.h | 20 ++++++++++++++++++++ 2 files changed, 24 insertions(+), 2 deletions(-) (limited to 'drivers/oprofile') diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c index d969bb1..f9031d3 100644 --- a/drivers/oprofile/buffer_sync.c +++ b/drivers/oprofile/buffer_sync.c @@ -524,6 +524,7 @@ void sync_buffer(int cpu) { struct mm_struct *mm = NULL; struct mm_struct *oldmm; + unsigned long val; struct task_struct *new; unsigned long cookie = 0; int in_kernel = 1; @@ -559,10 +560,11 @@ void sync_buffer(int cpu) state = sb_sample_start; add_kernel_ctx_switch(flags & IS_KERNEL); } - if (flags & USER_CTX_SWITCH) { + if (flags & USER_CTX_SWITCH + && op_cpu_buffer_get_data(&entry, &val)) { /* userspace context switch */ + new = (struct task_struct *)val; oldmm = mm; - new = (struct task_struct *)sample->data[0]; release_mm(oldmm); mm = take_tasks_mm(new); if (mm != oldmm) diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h index e178dd2..f343760 100644 --- a/drivers/oprofile/cpu_buffer.h +++ b/drivers/oprofile/cpu_buffer.h @@ -90,6 +90,26 @@ int op_cpu_buffer_add_data(struct op_entry *entry, unsigned long val) return entry->size; } +/* returns the size of data in the entry */ +static inline +int op_cpu_buffer_get_size(struct op_entry *entry) +{ + return entry->size; +} + +/* returns 0 if empty or the size of data including the current value */ +static inline +int op_cpu_buffer_get_data(struct op_entry *entry, unsigned long *val) +{ + int size = entry->size; + if (!size) + return 0; + *val = *entry->data; + entry->size--; + entry->data++; + return size; +} + /* extra data flags */ #define KERNEL_CTX_SWITCH (1UL << 0) #define IS_KERNEL (1UL << 1) -- cgit v1.1