diff options
| -rw-r--r-- | arch/Kconfig | 2 | ||||
| -rw-r--r-- | arch/x86/oprofile/op_model_amd.c | 89 | ||||
| -rw-r--r-- | drivers/oprofile/buffer_sync.c | 117 | ||||
| -rw-r--r-- | drivers/oprofile/cpu_buffer.c | 197 | ||||
| -rw-r--r-- | drivers/oprofile/cpu_buffer.h | 69 | ||||
| -rw-r--r-- | drivers/oprofile/oprofile_files.c | 15 | ||||
| -rw-r--r-- | include/linux/oprofile.h | 3 | ||||
| -rw-r--r-- | include/linux/ring_buffer.h | 2 | ||||
| -rw-r--r-- | kernel/trace/ring_buffer.c | 36 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 4 |
10 files changed, 306 insertions, 228 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 471e72d..2e13aa2 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -6,6 +6,8 @@ config OPROFILE tristate "OProfile system profiling (EXPERIMENTAL)" depends on PROFILING depends on HAVE_OPROFILE + select TRACING + select RING_BUFFER help OProfile is a profiling system capable of profiling the whole system, include the kernel, kernel modules, libraries, diff --git a/arch/x86/oprofile/op_model_amd.c b/arch/x86/oprofile/op_model_amd.c index 5095137..98658f2 100644 --- a/arch/x86/oprofile/op_model_amd.c +++ b/arch/x86/oprofile/op_model_amd.c @@ -65,11 +65,13 @@ static unsigned long reset_value[NUM_COUNTERS]; #define IBS_FETCH_BEGIN 3 #define IBS_OP_BEGIN 4 -/* The function interface needs to be fixed, something like add - data. Should then be added to linux/oprofile.h. */ +/* + * The function interface needs to be fixed, something like add + * data. Should then be added to linux/oprofile.h. + */ extern void -oprofile_add_ibs_sample(struct pt_regs *const regs, - unsigned int *const ibs_sample, int ibs_code); +oprofile_add_ibs_sample(struct pt_regs * const regs, + unsigned int * const ibs_sample, int ibs_code); struct ibs_fetch_sample { /* MSRC001_1031 IBS Fetch Linear Address Register */ @@ -104,11 +106,6 @@ struct ibs_op_sample { unsigned int ibs_dc_phys_high; }; -/* - * unitialize the APIC for the IBS interrupts if needed on AMD Family10h+ -*/ -static void clear_ibs_nmi(void); - static int ibs_allowed; /* AMD Family10h and later */ struct op_ibs_config { @@ -223,7 +220,7 @@ op_amd_handle_ibs(struct pt_regs * const regs, (unsigned int *)&ibs_fetch, IBS_FETCH_BEGIN); - /*reenable the IRQ */ + /* reenable the IRQ */ rdmsr(MSR_AMD64_IBSFETCHCTL, low, high); high &= ~IBS_FETCH_HIGH_VALID_BIT; high |= IBS_FETCH_HIGH_ENABLE; @@ -331,8 +328,10 @@ static void op_amd_stop(struct op_msrs const * const msrs) unsigned int low, high; int i; - /* Subtle: stop on all counters to avoid race with - * setting our pm callback */ + /* + * Subtle: stop on all counters to avoid race with setting our + * pm callback + */ for (i = 0 ; i < NUM_COUNTERS ; ++i) { if (!reset_value[i]) continue; @@ -343,13 +342,15 @@ static void op_amd_stop(struct op_msrs const * const msrs) #ifdef CONFIG_OPROFILE_IBS if (ibs_allowed && ibs_config.fetch_enabled) { - low = 0; /* clear max count and enable */ + /* clear max count and enable */ + low = 0; high = 0; wrmsr(MSR_AMD64_IBSFETCHCTL, low, high); } if (ibs_allowed && ibs_config.op_enabled) { - low = 0; /* clear max count and enable */ + /* clear max count and enable */ + low = 0; high = 0; wrmsr(MSR_AMD64_IBSOPCTL, low, high); } @@ -370,18 +371,7 @@ static void op_amd_shutdown(struct op_msrs const * const msrs) } } -#ifndef CONFIG_OPROFILE_IBS - -/* no IBS support */ - -static int op_amd_init(struct oprofile_operations *ops) -{ - return 0; -} - -static void op_amd_exit(void) {} - -#else +#ifdef CONFIG_OPROFILE_IBS static u8 ibs_eilvt_off; @@ -395,7 +385,7 @@ static inline void apic_clear_ibs_nmi_per_cpu(void *arg) setup_APIC_eilvt_ibs(0, APIC_EILVT_MSG_FIX, 1); } -static int pfm_amd64_setup_eilvt(void) +static int init_ibs_nmi(void) { #define IBSCTL_LVTOFFSETVAL (1 << 8) #define IBSCTL 0x1cc @@ -443,18 +433,22 @@ static int pfm_amd64_setup_eilvt(void) return 0; } -/* - * initialize the APIC for the IBS interrupts - * if available (AMD Family10h rev B0 and later) - */ -static void setup_ibs(void) +/* uninitialize the APIC for the IBS interrupts if needed */ +static void clear_ibs_nmi(void) +{ + if (ibs_allowed) + on_each_cpu(apic_clear_ibs_nmi_per_cpu, NULL, 1); +} + +/* initialize the APIC for the IBS interrupts if available */ +static void ibs_init(void) { ibs_allowed = boot_cpu_has(X86_FEATURE_IBS); if (!ibs_allowed) return; - if (pfm_amd64_setup_eilvt()) { + if (init_ibs_nmi()) { ibs_allowed = 0; return; } @@ -462,14 +456,12 @@ static void setup_ibs(void) printk(KERN_INFO "oprofile: AMD IBS detected\n"); } - -/* - * unitialize the APIC for the IBS interrupts if needed on AMD Family10h - * rev B0 and later */ -static void clear_ibs_nmi(void) +static void ibs_exit(void) { - if (ibs_allowed) - on_each_cpu(apic_clear_ibs_nmi_per_cpu, NULL, 1); + if (!ibs_allowed) + return; + + clear_ibs_nmi(); } static int (*create_arch_files)(struct super_block *sb, struct dentry *root); @@ -519,7 +511,7 @@ static int setup_ibs_files(struct super_block *sb, struct dentry *root) static int op_amd_init(struct oprofile_operations *ops) { - setup_ibs(); + ibs_init(); create_arch_files = ops->create_files; ops->create_files = setup_ibs_files; return 0; @@ -527,10 +519,21 @@ static int op_amd_init(struct oprofile_operations *ops) static void op_amd_exit(void) { - clear_ibs_nmi(); + ibs_exit(); } -#endif +#else + +/* no IBS support */ + +static int op_amd_init(struct oprofile_operations *ops) +{ + return 0; +} + +static void op_amd_exit(void) {} + +#endif /* CONFIG_OPROFILE_IBS */ struct op_x86_model_spec const op_amd_spec = { .init = op_amd_init, diff --git a/drivers/oprofile/buffer_sync.c b/drivers/oprofile/buffer_sync.c index b55cd23..737bd94 100644 --- a/drivers/oprofile/buffer_sync.c +++ b/drivers/oprofile/buffer_sync.c @@ -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); diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c index 01d38e7..6109096 100644 --- a/drivers/oprofile/cpu_buffer.c +++ b/drivers/oprofile/cpu_buffer.c @@ -28,6 +28,25 @@ #include "buffer_sync.h" #include "oprof.h" +#define OP_BUFFER_FLAGS 0 + +/* + * Read and write access is using spin locking. Thus, writing to the + * buffer by NMI handler (x86) could occur also during critical + * sections when reading the buffer. To avoid this, there are 2 + * buffers for independent read and write access. Read access is in + * process context only, write access only in the NMI handler. If the + * read buffer runs empty, both buffers are swapped atomically. There + * is potentially a small window during swapping where the buffers are + * disabled and samples could be lost. + * + * Using 2 buffers is a little bit overhead, but the solution is clear + * and does not require changes in the ring buffer implementation. It + * can be changed to a single buffer solution when the ring buffer + * access is implemented as non-locking atomic code. + */ +struct ring_buffer *op_ring_buffer_read; +struct ring_buffer *op_ring_buffer_write; DEFINE_PER_CPU(struct oprofile_cpu_buffer, cpu_buffer); static void wq_sync_buffer(struct work_struct *work); @@ -37,12 +56,12 @@ static int work_enabled; void free_cpu_buffers(void) { - int i; - - for_each_possible_cpu(i) { - vfree(per_cpu(cpu_buffer, i).buffer); - per_cpu(cpu_buffer, i).buffer = NULL; - } + if (op_ring_buffer_read) + ring_buffer_free(op_ring_buffer_read); + op_ring_buffer_read = NULL; + if (op_ring_buffer_write) + ring_buffer_free(op_ring_buffer_write); + op_ring_buffer_write = NULL; } unsigned long oprofile_get_cpu_buffer_size(void) @@ -64,14 +83,16 @@ int alloc_cpu_buffers(void) unsigned long buffer_size = fs_cpu_buffer_size; + op_ring_buffer_read = ring_buffer_alloc(buffer_size, OP_BUFFER_FLAGS); + if (!op_ring_buffer_read) + goto fail; + op_ring_buffer_write = ring_buffer_alloc(buffer_size, OP_BUFFER_FLAGS); + if (!op_ring_buffer_write) + goto fail; + for_each_possible_cpu(i) { struct oprofile_cpu_buffer *b = &per_cpu(cpu_buffer, i); - b->buffer = vmalloc_node(sizeof(struct op_sample) * buffer_size, - cpu_to_node(i)); - if (!b->buffer) - goto fail; - b->last_task = NULL; b->last_is_kernel = -1; b->tracing = 0; @@ -124,57 +145,31 @@ void end_cpu_work(void) flush_scheduled_work(); } -/* Resets the cpu buffer to a sane state. */ -void cpu_buffer_reset(struct oprofile_cpu_buffer *cpu_buf) -{ - /* reset these to invalid values; the next sample - * collected will populate the buffer with proper - * values to initialize the buffer - */ - cpu_buf->last_is_kernel = -1; - cpu_buf->last_task = NULL; -} - -/* compute number of available slots in cpu_buffer queue */ -static unsigned long nr_available_slots(struct oprofile_cpu_buffer const *b) +static inline int +add_sample(struct oprofile_cpu_buffer *cpu_buf, + unsigned long pc, unsigned long event) { - unsigned long head = b->head_pos; - unsigned long tail = b->tail_pos; + struct op_entry entry; + int ret; - if (tail > head) - return (tail - head) - 1; + ret = cpu_buffer_write_entry(&entry); + if (ret) + return ret; - return tail + (b->buffer_size - head) - 1; -} + entry.sample->eip = pc; + entry.sample->event = event; -static void increment_head(struct oprofile_cpu_buffer *b) -{ - unsigned long new_head = b->head_pos + 1; - - /* Ensure anything written to the slot before we - * increment is visible */ - wmb(); - - if (new_head < b->buffer_size) - b->head_pos = new_head; - else - b->head_pos = 0; -} + ret = cpu_buffer_write_commit(&entry); + if (ret) + return ret; -static inline void -add_sample(struct oprofile_cpu_buffer *cpu_buf, - unsigned long pc, unsigned long event) -{ - struct op_sample *entry = &cpu_buf->buffer[cpu_buf->head_pos]; - entry->eip = pc; - entry->event = event; - increment_head(cpu_buf); + return 0; } -static inline void +static inline int add_code(struct oprofile_cpu_buffer *buffer, unsigned long value) { - add_sample(buffer, ESCAPE_CODE, value); + return add_sample(buffer, ESCAPE_CODE, value); } /* This must be safe from any context. It's safe writing here @@ -198,11 +193,6 @@ static int log_sample(struct oprofile_cpu_buffer *cpu_buf, unsigned long pc, return 0; } - if (nr_available_slots(cpu_buf) < 3) { - cpu_buf->sample_lost_overflow++; - return 0; - } - is_kernel = !!is_kernel; task = current; @@ -210,26 +200,29 @@ static int log_sample(struct oprofile_cpu_buffer *cpu_buf, unsigned long pc, /* notice a switch from user->kernel or vice versa */ if (cpu_buf->last_is_kernel != is_kernel) { cpu_buf->last_is_kernel = is_kernel; - add_code(cpu_buf, is_kernel); + if (add_code(cpu_buf, is_kernel)) + goto fail; } /* notice a task switch */ if (cpu_buf->last_task != task) { cpu_buf->last_task = task; - add_code(cpu_buf, (unsigned long)task); + if (add_code(cpu_buf, (unsigned long)task)) + goto fail; } - add_sample(cpu_buf, pc, event); + if (add_sample(cpu_buf, pc, event)) + goto fail; + return 1; + +fail: + cpu_buf->sample_lost_overflow++; + return 0; } static int oprofile_begin_trace(struct oprofile_cpu_buffer *cpu_buf) { - if (nr_available_slots(cpu_buf) < 4) { - cpu_buf->sample_lost_overflow++; - return 0; - } - add_code(cpu_buf, CPU_TRACE_BEGIN); cpu_buf->tracing = 1; return 1; @@ -253,8 +246,10 @@ void oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs, if (!oprofile_begin_trace(cpu_buf)) return; - /* if log_sample() fail we can't backtrace since we lost the source - * of this event */ + /* + * if log_sample() fail we can't backtrace since we lost the + * source of this event + */ if (log_sample(cpu_buf, pc, is_kernel, event)) oprofile_ops.backtrace(regs, backtrace_depth); oprofile_end_trace(cpu_buf); @@ -272,49 +267,55 @@ void oprofile_add_sample(struct pt_regs * const regs, unsigned long event) #define MAX_IBS_SAMPLE_SIZE 14 -void oprofile_add_ibs_sample(struct pt_regs *const regs, - unsigned int *const ibs_sample, int ibs_code) +void oprofile_add_ibs_sample(struct pt_regs * const regs, + unsigned int * const ibs_sample, int ibs_code) { int is_kernel = !user_mode(regs); struct oprofile_cpu_buffer *cpu_buf = &__get_cpu_var(cpu_buffer); struct task_struct *task; + int fail = 0; cpu_buf->sample_received++; - if (nr_available_slots(cpu_buf) < MAX_IBS_SAMPLE_SIZE) { - /* we can't backtrace since we lost the source of this event */ - cpu_buf->sample_lost_overflow++; - return; - } - /* notice a switch from user->kernel or vice versa */ if (cpu_buf->last_is_kernel != is_kernel) { + if (add_code(cpu_buf, is_kernel)) + goto fail; cpu_buf->last_is_kernel = is_kernel; - add_code(cpu_buf, is_kernel); } /* notice a task switch */ if (!is_kernel) { task = current; if (cpu_buf->last_task != task) { + if (add_code(cpu_buf, (unsigned long)task)) + goto fail; cpu_buf->last_task = task; - add_code(cpu_buf, (unsigned long)task); } } - add_code(cpu_buf, ibs_code); - add_sample(cpu_buf, ibs_sample[0], ibs_sample[1]); - add_sample(cpu_buf, ibs_sample[2], ibs_sample[3]); - add_sample(cpu_buf, ibs_sample[4], ibs_sample[5]); + fail = fail || add_code(cpu_buf, ibs_code); + fail = fail || add_sample(cpu_buf, ibs_sample[0], ibs_sample[1]); + fail = fail || add_sample(cpu_buf, ibs_sample[2], ibs_sample[3]); + fail = fail || add_sample(cpu_buf, ibs_sample[4], ibs_sample[5]); if (ibs_code == IBS_OP_BEGIN) { - add_sample(cpu_buf, ibs_sample[6], ibs_sample[7]); - add_sample(cpu_buf, ibs_sample[8], ibs_sample[9]); - add_sample(cpu_buf, ibs_sample[10], ibs_sample[11]); + fail = fail || add_sample(cpu_buf, ibs_sample[6], ibs_sample[7]); + fail = fail || add_sample(cpu_buf, ibs_sample[8], ibs_sample[9]); + fail = fail || add_sample(cpu_buf, ibs_sample[10], ibs_sample[11]); } + if (fail) + goto fail; + if (backtrace_depth) oprofile_ops.backtrace(regs, backtrace_depth); + + return; + +fail: + cpu_buf->sample_lost_overflow++; + return; } #endif @@ -332,21 +333,21 @@ void oprofile_add_trace(unsigned long pc) if (!cpu_buf->tracing) return; - if (nr_available_slots(cpu_buf) < 1) { - cpu_buf->tracing = 0; - cpu_buf->sample_lost_overflow++; - return; - } + /* + * broken frame can give an eip with the same value as an + * escape code, abort the trace if we get it + */ + if (pc == ESCAPE_CODE) + goto fail; - /* broken frame can give an eip with the same value as an escape code, - * abort the trace if we get it */ - if (pc == ESCAPE_CODE) { - cpu_buf->tracing = 0; - cpu_buf->backtrace_aborted++; - return; - } + if (add_sample(cpu_buf, pc, 0)) + goto fail; - add_sample(cpu_buf, pc, 0); + return; +fail: + cpu_buf->tracing = 0; + cpu_buf->backtrace_aborted++; + return; } /* diff --git a/drivers/oprofile/cpu_buffer.h b/drivers/oprofile/cpu_buffer.h index d3cc262..aacb0f0 100644 --- a/drivers/oprofile/cpu_buffer.h +++ b/drivers/oprofile/cpu_buffer.h @@ -15,6 +15,7 @@ #include <linux/workqueue.h> #include <linux/cache.h> #include <linux/sched.h> +#include <linux/ring_buffer.h> struct task_struct; @@ -32,6 +33,12 @@ struct op_sample { unsigned long event; }; +struct op_entry { + struct ring_buffer_event *event; + struct op_sample *sample; + unsigned long irq_flags; +}; + struct oprofile_cpu_buffer { volatile unsigned long head_pos; volatile unsigned long tail_pos; @@ -39,7 +46,6 @@ struct oprofile_cpu_buffer { struct task_struct *last_task; int last_is_kernel; int tracing; - struct op_sample *buffer; unsigned long sample_received; unsigned long sample_lost_overflow; unsigned long backtrace_aborted; @@ -48,9 +54,68 @@ struct oprofile_cpu_buffer { struct delayed_work work; }; +extern struct ring_buffer *op_ring_buffer_read; +extern struct ring_buffer *op_ring_buffer_write; DECLARE_PER_CPU(struct oprofile_cpu_buffer, cpu_buffer); -void cpu_buffer_reset(struct oprofile_cpu_buffer *cpu_buf); +/* + * Resets the cpu buffer to a sane state. + * + * reset these to invalid values; the next sample collected will + * populate the buffer with proper values to initialize the buffer + */ +static inline void cpu_buffer_reset(int cpu) +{ + struct oprofile_cpu_buffer *cpu_buf = &per_cpu(cpu_buffer, cpu); + + cpu_buf->last_is_kernel = -1; + cpu_buf->last_task = NULL; +} + +static inline int cpu_buffer_write_entry(struct op_entry *entry) +{ + entry->event = ring_buffer_lock_reserve(op_ring_buffer_write, + sizeof(struct op_sample), + &entry->irq_flags); + if (entry->event) + entry->sample = ring_buffer_event_data(entry->event); + else + entry->sample = NULL; + + if (!entry->sample) + return -ENOMEM; + + return 0; +} + +static inline int cpu_buffer_write_commit(struct op_entry *entry) +{ + return ring_buffer_unlock_commit(op_ring_buffer_write, entry->event, + entry->irq_flags); +} + +static inline struct op_sample *cpu_buffer_read_entry(int cpu) +{ + struct ring_buffer_event *e; + e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL); + if (e) + return ring_buffer_event_data(e); + if (ring_buffer_swap_cpu(op_ring_buffer_read, + op_ring_buffer_write, + cpu)) + return NULL; + e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL); + if (e) + return ring_buffer_event_data(e); + return NULL; +} + +/* "acquire" as many cpu buffer slots as we can */ +static inline unsigned long cpu_buffer_entries(int cpu) +{ + return ring_buffer_entries_cpu(op_ring_buffer_read, cpu) + + ring_buffer_entries_cpu(op_ring_buffer_write, cpu); +} /* transient events for the CPU buffer -> event buffer */ #define CPU_IS_KERNEL 1 diff --git a/drivers/oprofile/oprofile_files.c b/drivers/oprofile/oprofile_files.c index cc106d5..d8201998 100644 --- a/drivers/oprofile/oprofile_files.c +++ b/drivers/oprofile/oprofile_files.c @@ -14,9 +14,13 @@ #include "oprofile_stats.h" #include "oprof.h" -unsigned long fs_buffer_size = 131072; -unsigned long fs_cpu_buffer_size = 8192; -unsigned long fs_buffer_watershed = 32768; /* FIXME: tune */ +#define FS_BUFFER_SIZE_DEFAULT 131072 +#define FS_CPU_BUFFER_SIZE_DEFAULT 8192 +#define FS_BUFFER_WATERSHED_DEFAULT 32768 /* FIXME: tune */ + +unsigned long fs_buffer_size; +unsigned long fs_cpu_buffer_size; +unsigned long fs_buffer_watershed; static ssize_t depth_read(struct file *file, char __user *buf, size_t count, loff_t *offset) { @@ -120,6 +124,11 @@ static const struct file_operations dump_fops = { void oprofile_create_files(struct super_block *sb, struct dentry *root) { + /* reinitialize default values */ + fs_buffer_size = FS_BUFFER_SIZE_DEFAULT; + fs_cpu_buffer_size = FS_CPU_BUFFER_SIZE_DEFAULT; + fs_buffer_watershed = FS_BUFFER_WATERSHED_DEFAULT; + oprofilefs_create_file(sb, root, "enable", &enable_fops); oprofilefs_create_file_perm(sb, root, "dump", &dump_fops, 0666); oprofilefs_create_file(sb, root, "buffer", &event_buffer_fops); diff --git a/include/linux/oprofile.h b/include/linux/oprofile.h index 5231861..1ce9fe5 100644 --- a/include/linux/oprofile.h +++ b/include/linux/oprofile.h @@ -86,8 +86,7 @@ int oprofile_arch_init(struct oprofile_operations * ops); void oprofile_arch_exit(void); /** - * Add a sample. This may be called from any context. Pass - * smp_processor_id() as cpu. + * Add a sample. This may be called from any context. */ void oprofile_add_sample(struct pt_regs * const regs, unsigned long event); diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h index d363467..b3b3596 100644 --- a/include/linux/ring_buffer.h +++ b/include/linux/ring_buffer.h @@ -118,6 +118,8 @@ void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu); unsigned long ring_buffer_entries(struct ring_buffer *buffer); unsigned long ring_buffer_overruns(struct ring_buffer *buffer); +unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu); +unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu); u64 ring_buffer_time_stamp(int cpu); void ring_buffer_normalize_time_stamp(int cpu, u64 *ts); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 76f34c0..1d601a7 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -69,6 +69,7 @@ void tracing_on(void) { set_bit(RB_BUFFERS_ON_BIT, &ring_buffer_flags); } +EXPORT_SYMBOL_GPL(tracing_on); /** * tracing_off - turn off all tracing buffers @@ -82,6 +83,7 @@ void tracing_off(void) { clear_bit(RB_BUFFERS_ON_BIT, &ring_buffer_flags); } +EXPORT_SYMBOL_GPL(tracing_off); /** * tracing_off_permanent - permanently disable ring buffers @@ -111,12 +113,14 @@ u64 ring_buffer_time_stamp(int cpu) return time; } +EXPORT_SYMBOL_GPL(ring_buffer_time_stamp); void ring_buffer_normalize_time_stamp(int cpu, u64 *ts) { /* Just stupid testing the normalize function and deltas */ *ts >>= DEBUG_SHIFT; } +EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp); #define RB_EVNT_HDR_SIZE (sizeof(struct ring_buffer_event)) #define RB_ALIGNMENT_SHIFT 2 @@ -166,6 +170,7 @@ unsigned ring_buffer_event_length(struct ring_buffer_event *event) { return rb_event_length(event); } +EXPORT_SYMBOL_GPL(ring_buffer_event_length); /* inline for ring buffer fast paths */ static inline void * @@ -187,6 +192,7 @@ void *ring_buffer_event_data(struct ring_buffer_event *event) { return rb_event_data(event); } +EXPORT_SYMBOL_GPL(ring_buffer_event_data); #define for_each_buffer_cpu(buffer, cpu) \ for_each_cpu_mask(cpu, buffer->cpumask) @@ -427,7 +433,7 @@ extern int ring_buffer_page_too_big(void); /** * ring_buffer_alloc - allocate a new ring_buffer - * @size: the size in bytes that is needed. + * @size: the size in bytes per cpu that is needed. * @flags: attributes to set for the ring buffer. * * Currently the only flag that is available is the RB_FL_OVERWRITE @@ -490,6 +496,7 @@ struct ring_buffer *ring_buffer_alloc(unsigned long size, unsigned flags) kfree(buffer); return NULL; } +EXPORT_SYMBOL_GPL(ring_buffer_alloc); /** * ring_buffer_free - free a ring buffer. @@ -505,6 +512,7 @@ ring_buffer_free(struct ring_buffer *buffer) kfree(buffer); } +EXPORT_SYMBOL_GPL(ring_buffer_free); static void rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer); @@ -680,6 +688,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) mutex_unlock(&buffer->mutex); return -ENOMEM; } +EXPORT_SYMBOL_GPL(ring_buffer_resize); static inline int rb_null_event(struct ring_buffer_event *event) { @@ -1304,6 +1313,7 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, ftrace_preempt_enable(resched); return NULL; } +EXPORT_SYMBOL_GPL(ring_buffer_lock_reserve); static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer, struct ring_buffer_event *event) @@ -1350,6 +1360,7 @@ int ring_buffer_unlock_commit(struct ring_buffer *buffer, return 0; } +EXPORT_SYMBOL_GPL(ring_buffer_unlock_commit); /** * ring_buffer_write - write data to the buffer without reserving @@ -1411,6 +1422,7 @@ int ring_buffer_write(struct ring_buffer *buffer, return ret; } +EXPORT_SYMBOL_GPL(ring_buffer_write); static inline int rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer) { @@ -1437,6 +1449,7 @@ void ring_buffer_record_disable(struct ring_buffer *buffer) { atomic_inc(&buffer->record_disabled); } +EXPORT_SYMBOL_GPL(ring_buffer_record_disable); /** * ring_buffer_record_enable - enable writes to the buffer @@ -1449,6 +1462,7 @@ void ring_buffer_record_enable(struct ring_buffer *buffer) { atomic_dec(&buffer->record_disabled); } +EXPORT_SYMBOL_GPL(ring_buffer_record_enable); /** * ring_buffer_record_disable_cpu - stop all writes into the cpu_buffer @@ -1470,6 +1484,7 @@ void ring_buffer_record_disable_cpu(struct ring_buffer *buffer, int cpu) cpu_buffer = buffer->buffers[cpu]; atomic_inc(&cpu_buffer->record_disabled); } +EXPORT_SYMBOL_GPL(ring_buffer_record_disable_cpu); /** * ring_buffer_record_enable_cpu - enable writes to the buffer @@ -1489,6 +1504,7 @@ void ring_buffer_record_enable_cpu(struct ring_buffer *buffer, int cpu) cpu_buffer = buffer->buffers[cpu]; atomic_dec(&cpu_buffer->record_disabled); } +EXPORT_SYMBOL_GPL(ring_buffer_record_enable_cpu); /** * ring_buffer_entries_cpu - get the number of entries in a cpu buffer @@ -1505,6 +1521,7 @@ unsigned long ring_buffer_entries_cpu(struct ring_buffer *buffer, int cpu) cpu_buffer = buffer->buffers[cpu]; return cpu_buffer->entries; } +EXPORT_SYMBOL_GPL(ring_buffer_entries_cpu); /** * ring_buffer_overrun_cpu - get the number of overruns in a cpu_buffer @@ -1521,6 +1538,7 @@ unsigned long ring_buffer_overrun_cpu(struct ring_buffer *buffer, int cpu) cpu_buffer = buffer->buffers[cpu]; return cpu_buffer->overrun; } +EXPORT_SYMBOL_GPL(ring_buffer_overrun_cpu); /** * ring_buffer_entries - get the number of entries in a buffer @@ -1543,6 +1561,7 @@ unsigned long ring_buffer_entries(struct ring_buffer *buffer) return entries; } +EXPORT_SYMBOL_GPL(ring_buffer_entries); /** * ring_buffer_overrun_cpu - get the number of overruns in buffer @@ -1565,6 +1584,7 @@ unsigned long ring_buffer_overruns(struct ring_buffer *buffer) return overruns; } +EXPORT_SYMBOL_GPL(ring_buffer_overruns); static void rb_iter_reset(struct ring_buffer_iter *iter) { @@ -1600,6 +1620,7 @@ void ring_buffer_iter_reset(struct ring_buffer_iter *iter) rb_iter_reset(iter); spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); } +EXPORT_SYMBOL_GPL(ring_buffer_iter_reset); /** * ring_buffer_iter_empty - check if an iterator has no more to read @@ -1614,6 +1635,7 @@ int ring_buffer_iter_empty(struct ring_buffer_iter *iter) return iter->head_page == cpu_buffer->commit_page && iter->head == rb_commit_index(cpu_buffer); } +EXPORT_SYMBOL_GPL(ring_buffer_iter_empty); static void rb_update_read_stamp(struct ring_buffer_per_cpu *cpu_buffer, @@ -1880,6 +1902,7 @@ rb_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) return NULL; } +EXPORT_SYMBOL_GPL(ring_buffer_peek); static struct ring_buffer_event * rb_iter_peek(struct ring_buffer_iter *iter, u64 *ts) @@ -1940,6 +1963,7 @@ rb_iter_peek(struct ring_buffer_iter *iter, u64 *ts) return NULL; } +EXPORT_SYMBOL_GPL(ring_buffer_iter_peek); /** * ring_buffer_peek - peek at the next event to be read @@ -2017,6 +2041,7 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts) return event; } +EXPORT_SYMBOL_GPL(ring_buffer_consume); /** * ring_buffer_read_start - start a non consuming read of the buffer @@ -2059,6 +2084,7 @@ ring_buffer_read_start(struct ring_buffer *buffer, int cpu) return iter; } +EXPORT_SYMBOL_GPL(ring_buffer_read_start); /** * ring_buffer_finish - finish reading the iterator of the buffer @@ -2075,6 +2101,7 @@ ring_buffer_read_finish(struct ring_buffer_iter *iter) atomic_dec(&cpu_buffer->record_disabled); kfree(iter); } +EXPORT_SYMBOL_GPL(ring_buffer_read_finish); /** * ring_buffer_read - read the next item in the ring buffer by the iterator @@ -2101,6 +2128,7 @@ ring_buffer_read(struct ring_buffer_iter *iter, u64 *ts) return event; } +EXPORT_SYMBOL_GPL(ring_buffer_read); /** * ring_buffer_size - return the size of the ring buffer (in bytes) @@ -2110,6 +2138,7 @@ unsigned long ring_buffer_size(struct ring_buffer *buffer) { return BUF_PAGE_SIZE * buffer->pages; } +EXPORT_SYMBOL_GPL(ring_buffer_size); static void rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer) @@ -2156,6 +2185,7 @@ void ring_buffer_reset_cpu(struct ring_buffer *buffer, int cpu) spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags); } +EXPORT_SYMBOL_GPL(ring_buffer_reset_cpu); /** * ring_buffer_reset - reset a ring buffer @@ -2168,6 +2198,7 @@ void ring_buffer_reset(struct ring_buffer *buffer) for_each_buffer_cpu(buffer, cpu) ring_buffer_reset_cpu(buffer, cpu); } +EXPORT_SYMBOL_GPL(ring_buffer_reset); /** * rind_buffer_empty - is the ring buffer empty? @@ -2186,6 +2217,7 @@ int ring_buffer_empty(struct ring_buffer *buffer) } return 1; } +EXPORT_SYMBOL_GPL(ring_buffer_empty); /** * ring_buffer_empty_cpu - is a cpu buffer of a ring buffer empty? @@ -2202,6 +2234,7 @@ int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu) cpu_buffer = buffer->buffers[cpu]; return rb_per_cpu_empty(cpu_buffer); } +EXPORT_SYMBOL_GPL(ring_buffer_empty_cpu); /** * ring_buffer_swap_cpu - swap a CPU buffer between two ring buffers @@ -2250,6 +2283,7 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a, return 0; } +EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu); static void rb_remove_entries(struct ring_buffer_per_cpu *cpu_buffer, struct buffer_data_page *bpage) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f4bb380..3608f6c 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1310,7 +1310,7 @@ enum trace_file_type { TRACE_FILE_ANNOTATE = 2, }; -static void trace_iterator_increment(struct trace_iterator *iter, int cpu) +static void trace_iterator_increment(struct trace_iterator *iter) { /* Don't allow ftrace to trace into the ring buffers */ ftrace_disable_cpu(); @@ -1389,7 +1389,7 @@ static void *find_next_entry_inc(struct trace_iterator *iter) iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); if (iter->ent) - trace_iterator_increment(iter, iter->cpu); + trace_iterator_increment(iter); return iter->ent ? iter : NULL; } |
