diff options
Diffstat (limited to 'drivers/oprofile/buffer_sync.c')
| -rw-r--r-- | drivers/oprofile/buffer_sync.c | 119 |
1 files changed, 41 insertions, 78 deletions
diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c index b55cd23ffdef..65e8294a9e29 100644 --- a/drivers/oprofile/buffer_sync.c +++ b/drivers/oprofile/buffer_sync.c @@ -200,7 +200,7 @@ static inline unsigned long fast_get_dcookie(struct path *path) { unsigned long cookie; - if (path->dentry->d_cookie) + if (path->dentry->d_flags & DCACHE_COOKIE) return (unsigned long)path->dentry; get_dcookie(path, &cookie); return cookie; @@ -268,18 +268,6 @@ lookup_dcookie(struct mm_struct *mm, unsigned long addr, off_t *offset) return cookie; } -static void increment_tail(struct oprofile_cpu_buffer *b) -{ - unsigned long new_tail = b->tail_pos + 1; - - rmb(); /* be sure fifo pointers are synchromized */ - - if (new_tail < b->buffer_size) - b->tail_pos = new_tail; - else - b->tail_pos = 0; -} - static unsigned long last_cookie = INVALID_COOKIE; static void add_cpu_switch(int i) @@ -331,28 +319,25 @@ static void add_trace_begin(void) #define IBS_FETCH_CODE_SIZE 2 #define IBS_OP_CODE_SIZE 5 -#define IBS_EIP(offset) \ - (((struct op_sample *)&cpu_buf->buffer[(offset)])->eip) -#define IBS_EVENT(offset) \ - (((struct op_sample *)&cpu_buf->buffer[(offset)])->event) /* * Add IBS fetch and op entries to event buffer */ -static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code, - struct mm_struct *mm) +static void add_ibs_begin(int cpu, int code, struct mm_struct *mm) { unsigned long rip; int i, count; unsigned long ibs_cookie = 0; off_t offset; + struct op_sample *sample; - increment_tail(cpu_buf); /* move to RIP entry */ - - rip = IBS_EIP(cpu_buf->tail_pos); + sample = cpu_buffer_read_entry(cpu); + if (!sample) + goto Error; + rip = sample->eip; #ifdef __LP64__ - rip += IBS_EVENT(cpu_buf->tail_pos) << 32; + rip += sample->event << 32; #endif if (mm) { @@ -376,8 +361,8 @@ static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code, add_event_entry(offset); /* Offset from Dcookie */ /* we send the Dcookie offset, but send the raw Linear Add also*/ - add_event_entry(IBS_EIP(cpu_buf->tail_pos)); - add_event_entry(IBS_EVENT(cpu_buf->tail_pos)); + add_event_entry(sample->eip); + add_event_entry(sample->event); if (code == IBS_FETCH_CODE) count = IBS_FETCH_CODE_SIZE; /*IBS FETCH is 2 int64s*/ @@ -385,10 +370,17 @@ static void add_ibs_begin(struct oprofile_cpu_buffer *cpu_buf, int code, count = IBS_OP_CODE_SIZE; /*IBS OP is 5 int64s*/ for (i = 0; i < count; i++) { - increment_tail(cpu_buf); - add_event_entry(IBS_EIP(cpu_buf->tail_pos)); - add_event_entry(IBS_EVENT(cpu_buf->tail_pos)); + sample = cpu_buffer_read_entry(cpu); + if (!sample) + goto Error; + add_event_entry(sample->eip); + add_event_entry(sample->event); } + + return; + +Error: + return; } #endif @@ -466,33 +458,6 @@ static inline int is_code(unsigned long val) } -/* "acquire" as many cpu buffer slots as we can */ -static unsigned long get_slots(struct oprofile_cpu_buffer *b) -{ - unsigned long head = b->head_pos; - unsigned long tail = b->tail_pos; - - /* - * Subtle. This resets the persistent last_task - * and in_kernel values used for switching notes. - * BUT, there is a small window between reading - * head_pos, and this call, that means samples - * can appear at the new head position, but not - * be prefixed with the notes for switching - * kernel mode or a task switch. This small hole - * can lead to mis-attribution or samples where - * we don't know if it's in the kernel or not, - * at the start of an event buffer. - */ - cpu_buffer_reset(b); - - if (head >= tail) - return head - tail; - - return head + (b->buffer_size - tail); -} - - /* Move tasks along towards death. Any tasks on dead_tasks * will definitely have no remaining references in any * CPU buffers at this point, because we use two lists, @@ -559,61 +524,61 @@ typedef enum { */ void sync_buffer(int cpu) { - struct oprofile_cpu_buffer *cpu_buf = &per_cpu(cpu_buffer, cpu); struct mm_struct *mm = NULL; + struct mm_struct *oldmm; struct task_struct *new; unsigned long cookie = 0; int in_kernel = 1; sync_buffer_state state = sb_buffer_start; -#ifndef CONFIG_OPROFILE_IBS unsigned int i; unsigned long available; -#endif mutex_lock(&buffer_mutex); add_cpu_switch(cpu); - /* Remember, only we can modify tail_pos */ - -#ifndef CONFIG_OPROFILE_IBS - available = get_slots(cpu_buf); + cpu_buffer_reset(cpu); + available = cpu_buffer_entries(cpu); for (i = 0; i < available; ++i) { -#else - while (get_slots(cpu_buf)) { -#endif - struct op_sample *s = &cpu_buf->buffer[cpu_buf->tail_pos]; + struct op_sample *s = cpu_buffer_read_entry(cpu); + if (!s) + break; if (is_code(s->eip)) { - if (s->event <= CPU_IS_KERNEL) { + switch (s->event) { + case 0: + case CPU_IS_KERNEL: /* kernel/userspace switch */ in_kernel = s->event; if (state == sb_buffer_start) state = sb_sample_start; add_kernel_ctx_switch(s->event); - } else if (s->event == CPU_TRACE_BEGIN) { + break; + case CPU_TRACE_BEGIN: state = sb_bt_start; add_trace_begin(); + break; #ifdef CONFIG_OPROFILE_IBS - } else if (s->event == IBS_FETCH_BEGIN) { + case IBS_FETCH_BEGIN: state = sb_bt_start; - add_ibs_begin(cpu_buf, IBS_FETCH_CODE, mm); - } else if (s->event == IBS_OP_BEGIN) { + add_ibs_begin(cpu, IBS_FETCH_CODE, mm); + break; + case IBS_OP_BEGIN: state = sb_bt_start; - add_ibs_begin(cpu_buf, IBS_OP_CODE, mm); + add_ibs_begin(cpu, IBS_OP_CODE, mm); + break; #endif - } else { - struct mm_struct *oldmm = mm; - + default: /* userspace context switch */ + oldmm = mm; new = (struct task_struct *)s->event; - release_mm(oldmm); mm = take_tasks_mm(new); if (mm != oldmm) cookie = get_exec_dcookie(mm); add_user_ctx_switch(new, cookie); + break; } } else if (state >= sb_bt_start && !add_sample(mm, s, in_kernel)) { @@ -622,8 +587,6 @@ void sync_buffer(int cpu) atomic_inc(&oprofile_stats.bt_lost_no_mapping); } } - - increment_tail(cpu_buf); } release_mm(mm); |