SMB3: Track total time spent on roundtrips for each SMB3 command

Also track minimum and maximum time by command in /proc/fs/cifs/Stats

Signed-off-by: Steve French <stfrench@microsoft.com>

3 files changed, 44 insertions, 6 deletions

diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index 13c1288b04a7..19ed9abe00de 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -462,8 +462,13 @@ static ssize_t cifs_stats_proc_write(struct file *file,
                         server = list_entry(tmp1, struct TCP_Server_Info,
                                             tcp_ses_list);
 #ifdef CONFIG_CIFS_STATS2
-                        for (i = 0; i < NUMBER_OF_SMB2_COMMANDS; i++)
+                        for (i = 0; i < NUMBER_OF_SMB2_COMMANDS; i++) {
+                                atomic_set(&server->num_cmds[i], 0);
                                 atomic_set(&server->smb2slowcmd[i], 0);
+                                server->time_per_cmd[i] = 0;
+                                server->slowest_cmd[i] = 0;
+                                server->fastest_cmd[0] = 0;
+                        }
 #endif /* CONFIG_CIFS_STATS2 */
                         list_for_each(tmp2, &server->smb_ses_list) {
                                 ses = list_entry(tmp2, struct cifs_ses,
@@ -531,9 +536,19 @@ static int cifs_stats_proc_show(struct seq_file *m, void *v)
                 server = list_entry(tmp1, struct TCP_Server_Info,
                                     tcp_ses_list);
 #ifdef CONFIG_CIFS_STATS2
+                seq_puts(m, "\nTotal time spent processing by command. Time ");
+                seq_printf(m, "units are jiffies (%d per second)\n", HZ);
+                seq_puts(m, "  SMB3 CMD\tNumber\tTotal Time\tFastest\tSlowest\n");
+                seq_puts(m, "  --------\t------\t----------\t-------\t-------\n");
+                for (j = 0; j < NUMBER_OF_SMB2_COMMANDS; j++)
+                        seq_printf(m, "  %d\t\t%d\t%llu\t\t%u\t%u\n", j,
+                                atomic_read(&server->num_cmds[j]),
+                                server->time_per_cmd[j],
+                                server->fastest_cmd[j],
+                                server->slowest_cmd[j]);
                 for (j = 0; j < NUMBER_OF_SMB2_COMMANDS; j++)
                         if (atomic_read(&server->smb2slowcmd[j]))
-                                seq_printf(m, "%d slow responses from %s for command %d\n",
+                                seq_printf(m, "  %d slow responses from %s for command %d\n",
                                         atomic_read(&server->smb2slowcmd[j]),
                                         server->hostname, j);
 #endif /* STATS2 */
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 585ad3207cb1..779ceb1f0412 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -714,7 +714,11 @@ struct TCP_Server_Info {
 #ifdef CONFIG_CIFS_STATS2
         atomic_t in_send; /* requests trying to send */
         atomic_t num_waiters;   /* blocked waiting to get in sendrecv */
+        atomic_t num_cmds[NUMBER_OF_SMB2_COMMANDS]; /* total requests by cmd */
         atomic_t smb2slowcmd[NUMBER_OF_SMB2_COMMANDS]; /* count resps > 1 sec */
+        __u64 time_per_cmd[NUMBER_OF_SMB2_COMMANDS]; /* total time per cmd */
+        __u32 slowest_cmd[NUMBER_OF_SMB2_COMMANDS];
+        __u32 fastest_cmd[NUMBER_OF_SMB2_COMMANDS];
 #endif /* STATS2 */
         unsigned int    max_read;
         unsigned int    max_write;
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 1de8e996e566..65d9f3e2eb88 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -104,7 +104,10 @@ DeleteMidQEntry(struct mid_q_entry *midEntry)
 {
 #ifdef CONFIG_CIFS_STATS2
         __le16 command = midEntry->server->vals->lock_cmd;
+        __u16 smb_cmd = le16_to_cpu(midEntry->command);
         unsigned long now;
+        unsigned long roundtrip_time;
+        struct TCP_Server_Info *server = midEntry->server;
 #endif
         midEntry->mid_state = MID_FREE;
         atomic_dec(&midCount);
@@ -114,6 +117,23 @@ DeleteMidQEntry(struct mid_q_entry *midEntry)
                 cifs_small_buf_release(midEntry->resp_buf);
 #ifdef CONFIG_CIFS_STATS2
         now = jiffies;
+        if (now < midEntry->when_alloc)
+                cifs_dbg(VFS, "invalid mid allocation time\n");
+        roundtrip_time = now - midEntry->when_alloc;
+
+        if (smb_cmd < NUMBER_OF_SMB2_COMMANDS) {
+                if (atomic_read(&server->num_cmds[smb_cmd]) == 0) {
+                        server->slowest_cmd[smb_cmd] = roundtrip_time;
+                        server->fastest_cmd[smb_cmd] = roundtrip_time;
+                } else {
+                        if (server->slowest_cmd[smb_cmd] < roundtrip_time)
+                                server->slowest_cmd[smb_cmd] = roundtrip_time;
+                        else if (server->fastest_cmd[smb_cmd] > roundtrip_time)
+                                server->fastest_cmd[smb_cmd] = roundtrip_time;
+                }
+                cifs_stats_inc(&server->num_cmds[smb_cmd]);
+                server->time_per_cmd[smb_cmd] += roundtrip_time;
+        }
         /*
          * commands taking longer than one second (default) can be indications
          * that something is wrong, unless it is quite a slow link or a very
@@ -131,11 +151,10 @@ DeleteMidQEntry(struct mid_q_entry *midEntry)
                  * smb2slowcmd[NUMBER_OF_SMB2_COMMANDS] counts by command
                  * NB: le16_to_cpu returns unsigned so can not be negative below
                  */
-                if (le16_to_cpu(midEntry->command) < NUMBER_OF_SMB2_COMMANDS)
-                        cifs_stats_inc(&midEntry->server->smb2slowcmd[le16_to_cpu(midEntry->command)]);
+                if (smb_cmd < NUMBER_OF_SMB2_COMMANDS)
+                        cifs_stats_inc(&server->smb2slowcmd[smb_cmd]);
 
-                trace_smb3_slow_rsp(le16_to_cpu(midEntry->command),
-                               midEntry->mid, midEntry->pid,
+                trace_smb3_slow_rsp(smb_cmd, midEntry->mid, midEntry->pid,
                                midEntry->when_sent, midEntry->when_received);
                 if (cifsFYI & CIFS_TIMER) {
                         pr_debug(" CIFS slow rsp: cmd %d mid %llu",