diff options
Diffstat (limited to 'arch/powerpc/oprofile/cell/spu_task_sync.c')
-rw-r--r-- | arch/powerpc/oprofile/cell/spu_task_sync.c | 236 |
1 files changed, 210 insertions, 26 deletions
diff --git a/arch/powerpc/oprofile/cell/spu_task_sync.c b/arch/powerpc/oprofile/cell/spu_task_sync.c index 2a9b4a049329..2949126d28d1 100644 --- a/arch/powerpc/oprofile/cell/spu_task_sync.c +++ b/arch/powerpc/oprofile/cell/spu_task_sync.c @@ -35,7 +35,102 @@ static DEFINE_SPINLOCK(buffer_lock); static DEFINE_SPINLOCK(cache_lock); static int num_spu_nodes; int spu_prof_num_nodes; -int last_guard_val[MAX_NUMNODES * 8]; + +struct spu_buffer spu_buff[MAX_NUMNODES * SPUS_PER_NODE]; +struct delayed_work spu_work; +static unsigned max_spu_buff; + +static void spu_buff_add(unsigned long int value, int spu) +{ + /* spu buff is a circular buffer. Add entries to the + * head. Head is the index to store the next value. + * The buffer is full when there is one available entry + * in the queue, i.e. head and tail can't be equal. + * That way we can tell the difference between the + * buffer being full versus empty. + * + * ASSUPTION: the buffer_lock is held when this function + * is called to lock the buffer, head and tail. + */ + int full = 1; + + if (spu_buff[spu].head >= spu_buff[spu].tail) { + if ((spu_buff[spu].head - spu_buff[spu].tail) + < (max_spu_buff - 1)) + full = 0; + + } else if (spu_buff[spu].tail > spu_buff[spu].head) { + if ((spu_buff[spu].tail - spu_buff[spu].head) + > 1) + full = 0; + } + + if (!full) { + spu_buff[spu].buff[spu_buff[spu].head] = value; + spu_buff[spu].head++; + + if (spu_buff[spu].head >= max_spu_buff) + spu_buff[spu].head = 0; + } else { + /* From the user's perspective make the SPU buffer + * size management/overflow look like we are using + * per cpu buffers. The user uses the same + * per cpu parameter to adjust the SPU buffer size. + * Increment the sample_lost_overflow to inform + * the user the buffer size needs to be increased. + */ + oprofile_cpu_buffer_inc_smpl_lost(); + } +} + +/* This function copies the per SPU buffers to the + * OProfile kernel buffer. + */ +void sync_spu_buff(void) +{ + int spu; + unsigned long flags; + int curr_head; + + for (spu = 0; spu < num_spu_nodes; spu++) { + /* In case there was an issue and the buffer didn't + * get created skip it. + */ + if (spu_buff[spu].buff == NULL) + continue; + + /* Hold the lock to make sure the head/tail + * doesn't change while spu_buff_add() is + * deciding if the buffer is full or not. + * Being a little paranoid. + */ + spin_lock_irqsave(&buffer_lock, flags); + curr_head = spu_buff[spu].head; + spin_unlock_irqrestore(&buffer_lock, flags); + + /* Transfer the current contents to the kernel buffer. + * data can still be added to the head of the buffer. + */ + oprofile_put_buff(spu_buff[spu].buff, + spu_buff[spu].tail, + curr_head, max_spu_buff); + + spin_lock_irqsave(&buffer_lock, flags); + spu_buff[spu].tail = curr_head; + spin_unlock_irqrestore(&buffer_lock, flags); + } + +} + +static void wq_sync_spu_buff(struct work_struct *work) +{ + /* move data from spu buffers to kernel buffer */ + sync_spu_buff(); + + /* only reschedule if profiling is not done */ + if (spu_prof_running) + schedule_delayed_work(&spu_work, DEFAULT_TIMER_EXPIRE); +} /* Container for caching information about an active SPU task. */ struct cached_info { @@ -305,14 +400,21 @@ static int process_context_switch(struct spu *spu, unsigned long objectId) /* Record context info in event buffer */ spin_lock_irqsave(&buffer_lock, flags); - add_event_entry(ESCAPE_CODE); - add_event_entry(SPU_CTX_SWITCH_CODE); - add_event_entry(spu->number); - add_event_entry(spu->pid); - add_event_entry(spu->tgid); - add_event_entry(app_dcookie); - add_event_entry(spu_cookie); - add_event_entry(offset); + spu_buff_add(ESCAPE_CODE, spu->number); + spu_buff_add(SPU_CTX_SWITCH_CODE, spu->number); + spu_buff_add(spu->number, spu->number); + spu_buff_add(spu->pid, spu->number); + spu_buff_add(spu->tgid, spu->number); + spu_buff_add(app_dcookie, spu->number); + spu_buff_add(spu_cookie, spu->number); + spu_buff_add(offset, spu->number); + + /* Set flag to indicate SPU PC data can now be written out. If + * the SPU program counter data is seen before an SPU context + * record is seen, the postprocessing will fail. + */ + spu_buff[spu->number].ctx_sw_seen = 1; + spin_unlock_irqrestore(&buffer_lock, flags); smp_wmb(); /* insure spu event buffer updates are written */ /* don't want entries intermingled... */ @@ -360,6 +462,47 @@ static int number_of_online_nodes(void) return nodes; } +static int oprofile_spu_buff_create(void) +{ + int spu; + + max_spu_buff = oprofile_get_cpu_buffer_size(); + + for (spu = 0; spu < num_spu_nodes; spu++) { + /* create circular buffers to store the data in. + * use locks to manage accessing the buffers + */ + spu_buff[spu].head = 0; + spu_buff[spu].tail = 0; + + /* + * Create a buffer for each SPU. Can't reliably + * create a single buffer for all spus due to not + * enough contiguous kernel memory. + */ + + spu_buff[spu].buff = kzalloc((max_spu_buff + * sizeof(unsigned long)), + GFP_KERNEL); + + if (!spu_buff[spu].buff) { + printk(KERN_ERR "SPU_PROF: " + "%s, line %d: oprofile_spu_buff_create " + "failed to allocate spu buffer %d.\n", + __func__, __LINE__, spu); + + /* release the spu buffers that have been allocated */ + while (spu >= 0) { + kfree(spu_buff[spu].buff); + spu_buff[spu].buff = 0; + spu--; + } + return -ENOMEM; + } + } + return 0; +} + /* The main purpose of this function is to synchronize * OProfile with SPUFS by registering to be notified of * SPU task switches. @@ -372,20 +515,35 @@ static int number_of_online_nodes(void) */ int spu_sync_start(void) { - int k; + int spu; int ret = SKIP_GENERIC_SYNC; int register_ret; unsigned long flags = 0; spu_prof_num_nodes = number_of_online_nodes(); num_spu_nodes = spu_prof_num_nodes * 8; + INIT_DELAYED_WORK(&spu_work, wq_sync_spu_buff); + + /* create buffer for storing the SPU data to put in + * the kernel buffer. + */ + ret = oprofile_spu_buff_create(); + if (ret) + goto out; spin_lock_irqsave(&buffer_lock, flags); - add_event_entry(ESCAPE_CODE); - add_event_entry(SPU_PROFILING_CODE); - add_event_entry(num_spu_nodes); + for (spu = 0; spu < num_spu_nodes; spu++) { + spu_buff_add(ESCAPE_CODE, spu); + spu_buff_add(SPU_PROFILING_CODE, spu); + spu_buff_add(num_spu_nodes, spu); + } spin_unlock_irqrestore(&buffer_lock, flags); + for (spu = 0; spu < num_spu_nodes; spu++) { + spu_buff[spu].ctx_sw_seen = 0; + spu_buff[spu].last_guard_val = 0; + } + /* Register for SPU events */ register_ret = spu_switch_event_register(&spu_active); if (register_ret) { @@ -393,8 +551,6 @@ int spu_sync_start(void) goto out; } - for (k = 0; k < (MAX_NUMNODES * 8); k++) - last_guard_val[k] = 0; pr_debug("spu_sync_start -- running.\n"); out: return ret; @@ -446,13 +602,20 @@ void spu_sync_buffer(int spu_num, unsigned int *samples, * use. We need to discard samples taken during the time * period which an overlay occurs (i.e., guard value changes). */ - if (grd_val && grd_val != last_guard_val[spu_num]) { - last_guard_val[spu_num] = grd_val; + if (grd_val && grd_val != spu_buff[spu_num].last_guard_val) { + spu_buff[spu_num].last_guard_val = grd_val; /* Drop the rest of the samples. */ break; } - add_event_entry(file_offset | spu_num_shifted); + /* We must ensure that the SPU context switch has been written + * out before samples for the SPU. Otherwise, the SPU context + * information is not available and the postprocessing of the + * SPU PC will fail with no available anonymous map information. + */ + if (spu_buff[spu_num].ctx_sw_seen) + spu_buff_add((file_offset | spu_num_shifted), + spu_num); } spin_unlock(&buffer_lock); out: @@ -463,20 +626,41 @@ out: int spu_sync_stop(void) { unsigned long flags = 0; - int ret = spu_switch_event_unregister(&spu_active); - if (ret) { + int ret; + int k; + + ret = spu_switch_event_unregister(&spu_active); + + if (ret) printk(KERN_ERR "SPU_PROF: " - "%s, line %d: spu_switch_event_unregister returned %d\n", - __func__, __LINE__, ret); - goto out; - } + "%s, line %d: spu_switch_event_unregister " \ + "returned %d\n", + __func__, __LINE__, ret); + + /* flush any remaining data in the per SPU buffers */ + sync_spu_buff(); spin_lock_irqsave(&cache_lock, flags); ret = release_cached_info(RELEASE_ALL); spin_unlock_irqrestore(&cache_lock, flags); -out: + + /* remove scheduled work queue item rather then waiting + * for every queued entry to execute. Then flush pending + * system wide buffer to event buffer. + */ + cancel_delayed_work(&spu_work); + + for (k = 0; k < num_spu_nodes; k++) { + spu_buff[k].ctx_sw_seen = 0; + + /* + * spu_sys_buff will be null if there was a problem + * allocating the buffer. Only delete if it exists. + */ + kfree(spu_buff[k].buff); + spu_buff[k].buff = 0; + } pr_debug("spu_sync_stop -- done.\n"); return ret; } - |