diff options
Diffstat (limited to 'arch/powerpc/oprofile/cell/spu_task_sync.c')
-rw-r--r-- | arch/powerpc/oprofile/cell/spu_task_sync.c | 657 |
1 files changed, 0 insertions, 657 deletions
diff --git a/arch/powerpc/oprofile/cell/spu_task_sync.c b/arch/powerpc/oprofile/cell/spu_task_sync.c deleted file mode 100644 index 489f993100d5..000000000000 --- a/arch/powerpc/oprofile/cell/spu_task_sync.c +++ /dev/null @@ -1,657 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * Cell Broadband Engine OProfile Support - * - * (C) Copyright IBM Corporation 2006 - * - * Author: Maynard Johnson <maynardj@us.ibm.com> - */ - -/* The purpose of this file is to handle SPU event task switching - * and to record SPU context information into the OProfile - * event buffer. - * - * Additionally, the spu_sync_buffer function is provided as a helper - * for recoding actual SPU program counter samples to the event buffer. - */ -#include <linux/dcookies.h> -#include <linux/kref.h> -#include <linux/mm.h> -#include <linux/fs.h> -#include <linux/file.h> -#include <linux/module.h> -#include <linux/notifier.h> -#include <linux/numa.h> -#include <linux/oprofile.h> -#include <linux/slab.h> -#include <linux/spinlock.h> -#include "pr_util.h" - -#define RELEASE_ALL 9999 - -static DEFINE_SPINLOCK(buffer_lock); -static DEFINE_SPINLOCK(cache_lock); -static int num_spu_nodes; -static int spu_prof_num_nodes; - -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. - * - * ASSUMPTION: 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. - */ -static 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 { - struct vma_to_fileoffset_map *map; - struct spu *the_spu; /* needed to access pointer to local_store */ - struct kref cache_ref; -}; - -static struct cached_info *spu_info[MAX_NUMNODES * 8]; - -static void destroy_cached_info(struct kref *kref) -{ - struct cached_info *info; - - info = container_of(kref, struct cached_info, cache_ref); - vma_map_free(info->map); - kfree(info); - module_put(THIS_MODULE); -} - -/* Return the cached_info for the passed SPU number. - * ATTENTION: Callers are responsible for obtaining the - * cache_lock if needed prior to invoking this function. - */ -static struct cached_info *get_cached_info(struct spu *the_spu, int spu_num) -{ - struct kref *ref; - struct cached_info *ret_info; - - if (spu_num >= num_spu_nodes) { - printk(KERN_ERR "SPU_PROF: " - "%s, line %d: Invalid index %d into spu info cache\n", - __func__, __LINE__, spu_num); - ret_info = NULL; - goto out; - } - if (!spu_info[spu_num] && the_spu) { - ref = spu_get_profile_private_kref(the_spu->ctx); - if (ref) { - spu_info[spu_num] = container_of(ref, struct cached_info, cache_ref); - kref_get(&spu_info[spu_num]->cache_ref); - } - } - - ret_info = spu_info[spu_num]; - out: - return ret_info; -} - - -/* Looks for cached info for the passed spu. If not found, the - * cached info is created for the passed spu. - * Returns 0 for success; otherwise, -1 for error. - */ -static int -prepare_cached_spu_info(struct spu *spu, unsigned long objectId) -{ - unsigned long flags; - struct vma_to_fileoffset_map *new_map; - int retval = 0; - struct cached_info *info; - - /* We won't bother getting cache_lock here since - * don't do anything with the cached_info that's returned. - */ - info = get_cached_info(spu, spu->number); - - if (info) { - pr_debug("Found cached SPU info.\n"); - goto out; - } - - /* Create cached_info and set spu_info[spu->number] to point to it. - * spu->number is a system-wide value, not a per-node value. - */ - info = kzalloc(sizeof(*info), GFP_KERNEL); - if (!info) { - printk(KERN_ERR "SPU_PROF: " - "%s, line %d: create vma_map failed\n", - __func__, __LINE__); - retval = -ENOMEM; - goto err_alloc; - } - new_map = create_vma_map(spu, objectId); - if (!new_map) { - printk(KERN_ERR "SPU_PROF: " - "%s, line %d: create vma_map failed\n", - __func__, __LINE__); - retval = -ENOMEM; - goto err_alloc; - } - - pr_debug("Created vma_map\n"); - info->map = new_map; - info->the_spu = spu; - kref_init(&info->cache_ref); - spin_lock_irqsave(&cache_lock, flags); - spu_info[spu->number] = info; - /* Increment count before passing off ref to SPUFS. */ - kref_get(&info->cache_ref); - - /* We increment the module refcount here since SPUFS is - * responsible for the final destruction of the cached_info, - * and it must be able to access the destroy_cached_info() - * function defined in the OProfile module. We decrement - * the module refcount in destroy_cached_info. - */ - try_module_get(THIS_MODULE); - spu_set_profile_private_kref(spu->ctx, &info->cache_ref, - destroy_cached_info); - spin_unlock_irqrestore(&cache_lock, flags); - goto out; - -err_alloc: - kfree(info); -out: - return retval; -} - -/* - * NOTE: The caller is responsible for locking the - * cache_lock prior to calling this function. - */ -static int release_cached_info(int spu_index) -{ - int index, end; - - if (spu_index == RELEASE_ALL) { - end = num_spu_nodes; - index = 0; - } else { - if (spu_index >= num_spu_nodes) { - printk(KERN_ERR "SPU_PROF: " - "%s, line %d: " - "Invalid index %d into spu info cache\n", - __func__, __LINE__, spu_index); - goto out; - } - end = spu_index + 1; - index = spu_index; - } - for (; index < end; index++) { - if (spu_info[index]) { - kref_put(&spu_info[index]->cache_ref, - destroy_cached_info); - spu_info[index] = NULL; - } - } - -out: - return 0; -} - -/* The source code for fast_get_dcookie was "borrowed" - * from drivers/oprofile/buffer_sync.c. - */ - -/* Optimisation. We can manage without taking the dcookie sem - * because we cannot reach this code without at least one - * dcookie user still being registered (namely, the reader - * of the event buffer). - */ -static inline unsigned long fast_get_dcookie(const struct path *path) -{ - unsigned long cookie; - - if (path->dentry->d_flags & DCACHE_COOKIE) - return (unsigned long)path->dentry; - get_dcookie(path, &cookie); - return cookie; -} - -/* Look up the dcookie for the task's mm->exe_file, - * which corresponds loosely to "application name". Also, determine - * the offset for the SPU ELF object. If computed offset is - * non-zero, it implies an embedded SPU object; otherwise, it's a - * separate SPU binary, in which case we retrieve it's dcookie. - * For the embedded case, we must determine if SPU ELF is embedded - * in the executable application or another file (i.e., shared lib). - * If embedded in a shared lib, we must get the dcookie and return - * that to the caller. - */ -static unsigned long -get_exec_dcookie_and_offset(struct spu *spu, unsigned int *offsetp, - unsigned long *spu_bin_dcookie, - unsigned long spu_ref) -{ - unsigned long app_cookie = 0; - unsigned int my_offset = 0; - struct vm_area_struct *vma; - struct file *exe_file; - struct mm_struct *mm = spu->mm; - - if (!mm) - goto out; - - exe_file = get_mm_exe_file(mm); - if (exe_file) { - app_cookie = fast_get_dcookie(&exe_file->f_path); - pr_debug("got dcookie for %pD\n", exe_file); - fput(exe_file); - } - - mmap_read_lock(mm); - for (vma = mm->mmap; vma; vma = vma->vm_next) { - if (vma->vm_start > spu_ref || vma->vm_end <= spu_ref) - continue; - my_offset = spu_ref - vma->vm_start; - if (!vma->vm_file) - goto fail_no_image_cookie; - - pr_debug("Found spu ELF at %X(object-id:%lx) for file %pD\n", - my_offset, spu_ref, vma->vm_file); - *offsetp = my_offset; - break; - } - - *spu_bin_dcookie = fast_get_dcookie(&vma->vm_file->f_path); - pr_debug("got dcookie for %pD\n", vma->vm_file); - - mmap_read_unlock(mm); - -out: - return app_cookie; - -fail_no_image_cookie: - mmap_read_unlock(mm); - - printk(KERN_ERR "SPU_PROF: " - "%s, line %d: Cannot find dcookie for SPU binary\n", - __func__, __LINE__); - goto out; -} - - - -/* This function finds or creates cached context information for the - * passed SPU and records SPU context information into the OProfile - * event buffer. - */ -static int process_context_switch(struct spu *spu, unsigned long objectId) -{ - unsigned long flags; - int retval; - unsigned int offset = 0; - unsigned long spu_cookie = 0, app_dcookie; - - retval = prepare_cached_spu_info(spu, objectId); - if (retval) - goto out; - - /* Get dcookie first because a mutex_lock is taken in that - * code path, so interrupts must not be disabled. - */ - app_dcookie = get_exec_dcookie_and_offset(spu, &offset, &spu_cookie, objectId); - if (!app_dcookie || !spu_cookie) { - retval = -ENOENT; - goto out; - } - - /* Record context info in event buffer */ - spin_lock_irqsave(&buffer_lock, flags); - 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... */ -out: - return retval; -} - -/* - * This function is invoked on either a bind_context or unbind_context. - * If called for an unbind_context, the val arg is 0; otherwise, - * it is the object-id value for the spu context. - * The data arg is of type 'struct spu *'. - */ -static int spu_active_notify(struct notifier_block *self, unsigned long val, - void *data) -{ - int retval; - unsigned long flags; - struct spu *the_spu = data; - - pr_debug("SPU event notification arrived\n"); - if (!val) { - spin_lock_irqsave(&cache_lock, flags); - retval = release_cached_info(the_spu->number); - spin_unlock_irqrestore(&cache_lock, flags); - } else { - retval = process_context_switch(the_spu, val); - } - return retval; -} - -static struct notifier_block spu_active = { - .notifier_call = spu_active_notify, -}; - -static int number_of_online_nodes(void) -{ - u32 cpu; u32 tmp; - int nodes = 0; - for_each_online_cpu(cpu) { - tmp = cbe_cpu_to_node(cpu) + 1; - if (tmp > nodes) - nodes++; - } - 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. - * - * NOTE: When profiling SPUs, we must ensure that only - * spu_sync_start is invoked and not the generic sync_start - * in drivers/oprofile/oprof.c. A return value of - * SKIP_GENERIC_SYNC or SYNC_START_ERROR will - * accomplish this. - */ -int spu_sync_start(void) -{ - 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); - 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) { - ret = SYNC_START_ERROR; - goto out; - } - - pr_debug("spu_sync_start -- running.\n"); -out: - return ret; -} - -/* Record SPU program counter samples to the oprofile event buffer. */ -void spu_sync_buffer(int spu_num, unsigned int *samples, - int num_samples) -{ - unsigned long long file_offset; - unsigned long flags; - int i; - struct vma_to_fileoffset_map *map; - struct spu *the_spu; - unsigned long long spu_num_ll = spu_num; - unsigned long long spu_num_shifted = spu_num_ll << 32; - struct cached_info *c_info; - - /* We need to obtain the cache_lock here because it's - * possible that after getting the cached_info, the SPU job - * corresponding to this cached_info may end, thus resulting - * in the destruction of the cached_info. - */ - spin_lock_irqsave(&cache_lock, flags); - c_info = get_cached_info(NULL, spu_num); - if (!c_info) { - /* This legitimately happens when the SPU task ends before all - * samples are recorded. - * No big deal -- so we just drop a few samples. - */ - pr_debug("SPU_PROF: No cached SPU context " - "for SPU #%d. Dropping samples.\n", spu_num); - goto out; - } - - map = c_info->map; - the_spu = c_info->the_spu; - spin_lock(&buffer_lock); - for (i = 0; i < num_samples; i++) { - unsigned int sample = *(samples+i); - int grd_val = 0; - file_offset = 0; - if (sample == 0) - continue; - file_offset = vma_map_lookup( map, sample, the_spu, &grd_val); - - /* If overlays are used by this SPU application, the guard - * value is non-zero, indicating which overlay section is in - * 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 != spu_buff[spu_num].last_guard_val) { - spu_buff[spu_num].last_guard_val = grd_val; - /* Drop the rest of the samples. */ - break; - } - - /* 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: - spin_unlock_irqrestore(&cache_lock, flags); -} - - -int spu_sync_stop(void) -{ - unsigned long flags = 0; - 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); - - /* 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); - - /* 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; -} - |