Branch and cache miss speedups
Just some low hanging fruit.
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/compiler/compiler.h b/compiler/compiler.h
index 036ba20..0a0213b 100644
--- a/compiler/compiler.h
+++ b/compiler/compiler.h
@@ -20,4 +20,6 @@
#define fio_init __attribute__((constructor))
#define fio_exit __attribute__((destructor))
+#define fio_unlikely(x) __builtin_expect(!!(x), 0)
+
#endif
diff --git a/filesetup.c b/filesetup.c
index 1acf6ad..2744d4f 100644
--- a/filesetup.c
+++ b/filesetup.c
@@ -1010,7 +1010,7 @@
seed = td->rand_seeds[FIO_RAND_BLOCK_OFF];
- if (!lfsr_init(&f->lfsr, blocks, seed, seed & 0xF))
+ if (!lfsr_init(&f->lfsr, blocks, seed, 0))
continue;
} else if (!td->o.norandommap) {
f->io_axmap = axmap_new(blocks);
diff --git a/gettime.c b/gettime.c
index 277f2cf..8991703 100644
--- a/gettime.c
+++ b/gettime.c
@@ -205,7 +205,7 @@
gtod_log_caller(caller);
#endif
- if (fio_tv) {
+ if (fio_unlikely(fio_tv)) {
memcpy(tp, fio_tv, sizeof(*tp));
return;
}
diff --git a/io_u.c b/io_u.c
index a69efb7..77557df 100644
--- a/io_u.c
+++ b/io_u.c
@@ -1307,9 +1307,9 @@
else if (!queue_full(td)) {
io_u = io_u_qpop(&td->io_u_freelist);
+ io_u->file = NULL;
io_u->buflen = 0;
io_u->resid = 0;
- io_u->file = NULL;
io_u->end_io = NULL;
}
diff --git a/ioengine.h b/ioengine.h
index abf2b46..7e0707b 100644
--- a/ioengine.h
+++ b/ioengine.h
@@ -73,6 +73,25 @@
struct io_piece *ipo;
+ unsigned int resid;
+ unsigned int error;
+
+ /*
+ * io engine private data
+ */
+ union {
+ unsigned int index;
+ unsigned int seen;
+ void *engine_data;
+ };
+
+ struct flist_head verify_list;
+
+ /*
+ * Callback for io completion
+ */
+ int (*end_io)(struct thread_data *, struct io_u *);
+
union {
#ifdef CONFIG_LIBAIO
struct iocb iocb;
@@ -97,25 +116,6 @@
#endif
void *mmap_data;
};
-
- unsigned int resid;
- unsigned int error;
-
- /*
- * io engine private data
- */
- union {
- unsigned int index;
- unsigned int seen;
- void *engine_data;
- };
-
- struct flist_head verify_list;
-
- /*
- * Callback for io completion
- */
- int (*end_io)(struct thread_data *, struct io_u *);
};
/*
diff --git a/lib/lfsr.c b/lib/lfsr.c
index 927b2a1..9771318 100644
--- a/lib/lfsr.c
+++ b/lib/lfsr.c
@@ -2,6 +2,7 @@
#include <math.h>
#include "lfsr.h"
+#include "../compiler/compiler.h"
/*
* LFSR taps retrieved from:
@@ -132,11 +133,9 @@
if (fl->cycle_length && !--fl->cycle_length) {
__lfsr_next(fl, fl->spin + 1);
fl->cycle_length = fl->cached_cycle_length;
- goto check;
- }
- __lfsr_next(fl, fl->spin);
-check: ;
- } while (fl->last_val > fl->max_val);
+ } else
+ __lfsr_next(fl, fl->spin);
+ } while (fio_unlikely(fl->last_val > fl->max_val));
*off = fl->last_val;
return 0;