#include <assert.h>
#include "blktrace.h"
-#include "list.h"
+#include "barrier.h"
static char blktrace_version[] = "0.99";
};
struct tip_subbuf {
- struct list_head list;
void *buf;
unsigned int len;
unsigned int max_len;
};
+#define FIFO_SIZE (1024) /* should be plenty big! */
+#define CL_SIZE (128) /* cache line, any bigger? */
+
+struct tip_subbuf_fifo {
+ int tail __attribute__((aligned(CL_SIZE)));
+ int head __attribute__((aligned(CL_SIZE)));
+ struct tip_subbuf *q[FIFO_SIZE];
+};
+
struct thread_information {
int cpu;
pthread_t thread;
int exited;
- pthread_mutex_t lock;
- struct list_head subbuf_list;
+ struct tip_subbuf_fifo fifo;
struct tip_subbuf *leftover_ts;
};
return ret;
}
-static inline void tip_fd_unlock(struct thread_information *tip)
+static inline struct tip_subbuf *subbuf_fifo_dequeue(struct thread_information *tip)
{
- pthread_mutex_unlock(&tip->lock);
+ const int head = tip->fifo.head;
+ const int next = (head + 1) & (FIFO_SIZE - 1);
+
+ if (head != tip->fifo.tail) {
+ struct tip_subbuf *ts = tip->fifo.q[head];
+
+ store_barrier();
+ tip->fifo.head = next;
+ return ts;
+ }
+
+ return NULL;
}
-static inline void tip_fd_lock(struct thread_information *tip)
+static inline int subbuf_fifo_queue(struct thread_information *tip,
+ struct tip_subbuf *ts)
{
- pthread_mutex_lock(&tip->lock);
+ const int tail = tip->fifo.tail;
+ const int next = (tail + 1) & (FIFO_SIZE - 1);
+
+ if (next != tip->fifo.head) {
+ tip->fifo.q[tail] = ts;
+ store_barrier();
+ tip->fifo.tail = next;
+ return 0;
+ }
+
+ fprintf(stderr, "fifo too small!\n");
+ return 1;
}
static int get_subbuf(struct thread_information *tip)
ret = read_data(tip, ts->buf, ts->max_len);
if (ret > 0) {
ts->len = ret;
- tip_fd_lock(tip);
- list_add_tail(&ts->list, &tip->subbuf_list);
- tip_fd_unlock(tip);
- return 0;
+ return subbuf_fifo_queue(tip, ts);
}
free(ts->buf);
static int write_tip_events(struct thread_information *tip)
{
- struct tip_subbuf *ts = NULL;
-
- tip_fd_lock(tip);
- if (!list_empty(&tip->subbuf_list)) {
- ts = list_entry(tip->subbuf_list.next, struct tip_subbuf, list);
- list_del(&ts->list);
- }
- tip_fd_unlock(tip);
+ struct tip_subbuf *ts = subbuf_fifo_dequeue(tip);
if (ts)
return flush_subbuf(tip, ts);
tip->cpu = j;
tip->device = dip;
tip->events_processed = 0;
- pthread_mutex_init(&tip->lock, NULL);
- INIT_LIST_HEAD(&tip->subbuf_list);
+ memset(&tip->fifo, 0, sizeof(tip->fifo));
tip->leftover_ts = NULL;
if (pipeline) {
+++ /dev/null
-#ifndef _LINUX_LIST_H
-#define _LINUX_LIST_H
-
-#undef offsetof
-#ifdef __compiler_offsetof
-#define offsetof(TYPE,MEMBER) __compiler_offsetof(TYPE,MEMBER)
-#else
-#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
-#endif
-
-#define container_of(ptr, type, member) ({ \
- const typeof( ((type *)0)->member ) *__mptr = (ptr); \
- (type *)( (char *)__mptr - offsetof(type,member) );})
-
-/*
- * Simple doubly linked list implementation.
- *
- * Some of the internal functions ("__xxx") are useful when
- * manipulating whole lists rather than single entries, as
- * sometimes we already know the next/prev entries and we can
- * generate better code by using them directly rather than
- * using the generic single-entry routines.
- */
-
-struct list_head {
- struct list_head *next, *prev;
-};
-
-#define LIST_HEAD_INIT(name) { &(name), &(name) }
-
-#define LIST_HEAD(name) \
- struct list_head name = LIST_HEAD_INIT(name)
-
-#define INIT_LIST_HEAD(ptr) do { \
- (ptr)->next = (ptr); (ptr)->prev = (ptr); \
-} while (0)
-
-/*
- * Insert a new entry between two known consecutive entries.
- *
- * This is only for internal list manipulation where we know
- * the prev/next entries already!
- */
-static inline void __list_add(struct list_head *new,
- struct list_head *prev,
- struct list_head *next)
-{
- next->prev = new;
- new->next = next;
- new->prev = prev;
- prev->next = new;
-}
-
-/**
- * list_add - add a new entry
- * @new: new entry to be added
- * @head: list head to add it after
- *
- * Insert a new entry after the specified head.
- * This is good for implementing stacks.
- */
-static inline void list_add(struct list_head *new, struct list_head *head)
-{
- __list_add(new, head, head->next);
-}
-
-static inline void list_add_tail(struct list_head *new, struct list_head *head)
-{
- __list_add(new, head->prev, head);
-}
-
-/*
- * Delete a list entry by making the prev/next entries
- * point to each other.
- *
- * This is only for internal list manipulation where we know
- * the prev/next entries already!
- */
-static inline void __list_del(struct list_head * prev, struct list_head * next)
-{
- next->prev = prev;
- prev->next = next;
-}
-
-/**
- * list_del - deletes entry from list.
- * @entry: the element to delete from the list.
- * Note: list_empty on entry does not return true after this, the entry is
- * in an undefined state.
- */
-static inline void list_del(struct list_head *entry)
-{
- __list_del(entry->prev, entry->next);
- entry->next = NULL;
- entry->prev = NULL;
-}
-
-/**
- * list_empty - tests whether a list is empty
- * @head: the list to test.
- */
-static inline int list_empty(const struct list_head *head)
-{
- return head->next == head;
-}
-
-/**
- * list_entry - get the struct for this entry
- * @ptr: the &struct list_head pointer.
- * @type: the type of the struct this is embedded in.
- * @member: the name of the list_struct within the struct.
- */
-#define list_entry(ptr, type, member) \
- container_of(ptr, type, member)
-
-/**
- * list_for_each - iterate over a list
- * @pos: the &struct list_head to use as a loop counter.
- * @head: the head for your list.
- */
-#define list_for_each(pos, head) \
- for (pos = (head)->next; pos != (head); pos = pos->next)
-
-/**
- * list_for_each_safe - iterate over a list safe against removal of list entry
- * @pos: the &struct list_head to use as a loop counter.
- * @n: another &struct list_head to use as temporary storage
- * @head: the head for your list.
- */
-#define list_for_each_safe(pos, n, head) \
- for (pos = (head)->next, n = pos->next; pos != (head); \
- pos = n, n = pos->next)
-
-#endif
projects / blktrace.git / commitdiff