stat: add a new function to allocate a clat_prio_stat array

To be able to report clat stats on a per priority granularity (instead of
only high/low priority), we need a new function which allocates a
clat_prio_stat array. This array will hold the clat stats for all the
different priorities that will be used by the struct td.

The clat_prio_stat array will eventually replace io_u_plat_high_prio,
io_u_plat_low_prio, clat_high_prio_stat, and clat_low_prio_stat.

A follow up patch will convert stat.c to use the new array.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20220203192814.18552-6-Niklas.Cassel@wdc.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/stat.c b/stat.c
index b08d2f25df0e7353222d3346a80b21a3100bca39..c8680a679bf3667bf62c46967c5d44a53a01697d 100644 (file)
--- a/stat.c
+++ b/stat.c
@@ -1995,6 +1995,46 @@ void sum_group_stats(struct group_run_stats *dst, struct group_run_stats *src)
                dst->sig_figs = src->sig_figs;
 }
 
+/*
+ * Free the clat_prio_stat arrays allocated by alloc_clat_prio_stat_ddir().
+ */
+void free_clat_prio_stats(struct thread_stat *ts)
+{
+       enum fio_ddir ddir;
+
+       for (ddir = 0; ddir < DDIR_RWDIR_CNT; ddir++) {
+               sfree(ts->clat_prio[ddir]);
+               ts->clat_prio[ddir] = NULL;
+               ts->nr_clat_prio[ddir] = 0;
+       }
+}
+
+/*
+ * Allocate a clat_prio_stat array. The array has to be allocated/freed using
+ * smalloc/sfree, so that it is accessible by the process/thread summing the
+ * thread_stats.
+ */
+int alloc_clat_prio_stat_ddir(struct thread_stat *ts, enum fio_ddir ddir,
+                             int nr_prios)
+{
+       struct clat_prio_stat *clat_prio;
+       int i;
+
+       clat_prio = scalloc(nr_prios, sizeof(*ts->clat_prio[ddir]));
+       if (!clat_prio) {
+               log_err("fio: failed to allocate ts clat data\n");
+               return 1;
+       }
+
+       for (i = 0; i < nr_prios; i++)
+               clat_prio[i].clat_stat.min_val = ULONG_MAX;
+
+       ts->clat_prio[ddir] = clat_prio;
+       ts->nr_clat_prio[ddir] = nr_prios;
+
+       return 0;
+}
+
 void sum_thread_stats(struct thread_stat *dst, struct thread_stat *src)
 {
        int k, l, m;

diff --git a/stat.h b/stat.h
index 5fa20f7441010d0d6f9c8d0862ad0583c4357b0c..188c57f3f827b4657c8a07cde9595000db2de557 100644 (file)
--- a/stat.h
+++ b/stat.h
@@ -158,6 +158,12 @@ enum fio_lat {
        FIO_LAT_CNT = 3,
 };
 
+struct clat_prio_stat {
+       uint64_t io_u_plat[FIO_IO_U_PLAT_NR];
+       struct io_stat clat_stat;
+       uint32_t ioprio;
+};
+
 struct thread_stat {
        char name[FIO_JOBNAME_SIZE];
        char verror[FIO_VERROR_SIZE];
@@ -280,6 +286,17 @@ struct thread_stat {
                uint64_t pad5;
        };
 
+       union {
+               struct clat_prio_stat *clat_prio[DDIR_RWDIR_CNT];
+               /*
+                * For FIO_NET_CMD_TS, the pointed to data will temporarily
+                * be stored at this offset from the start of the payload.
+                */
+               uint64_t clat_prio_offset[DDIR_RWDIR_CNT];
+               uint64_t pad6;
+       };
+       uint32_t nr_clat_prio[DDIR_RWDIR_CNT];
+
        uint64_t cachehit;
        uint64_t cachemiss;
 } __attribute__((packed));
@@ -368,6 +385,8 @@ extern void add_bw_sample(struct thread_data *, struct io_u *,
 extern void add_sync_clat_sample(struct thread_stat *ts,
                                unsigned long long nsec);
 extern int calc_log_samples(void);
+extern void free_clat_prio_stats(struct thread_stat *);
+extern int alloc_clat_prio_stat_ddir(struct thread_stat *, enum fio_ddir, int);
 
 extern void print_disk_util(struct disk_util_stat *, struct disk_util_agg *, int terse, struct buf_output *);
 extern void json_array_add_disk_util(struct disk_util_stat *dus,