Re: [PATCH] prevent the read ahead of /proc/slabinfo in ss - take 3

From: Sergei Shtylyov <hidden>
Date: 2015-02-10 12:51:32

On 2/10/2015 8:52 AM, Bryton Lee wrote:

prevent the read ahead of /proc/slabinfo in ss.

Signed-off-by: Bryton Lee <redacted>
---
  misc/ss.c | 13 ++++++++++---
  1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/misc/ss.c b/misc/ss.c
index 7fc0a99..74721b5 100644
--- a/misc/ss.c
+++ b/misc/ss.c

[...]

@@ -655,6 +656,8 @@ static int get_slabstat(struct slabstat *s)
  			break;
  	}

+    slabstat_valid = 1;

   This is indented incorrectly. Use one TAB please.

+
  	fclose(fp);
  	return 0;
  }

@@ -2230,6 +2233,9 @@ static int tcp_show(struct filter *f, int socktype)
  	 * it is able to give us some memory for snapshot.
  	 */
  	if (1) {
+		if (!slabstat_valid)
+			get_slabstat(&slabstat);
+
  		int guess = slabstat.socks+slabstat.tcp_syns;
  		if (f->states&(1<<SS_TIME_WAIT))
  			guess += slabstat.tcp_tws;
@@ -3196,6 +3202,9 @@ static int print_summary(void)
  	if (get_snmp_int("Tcp:", "CurrEstab", &sn.tcp_estab) < 0)
  		perror("ss: get_snmpstat");

+	if (!slabstat_valid)
+		get_slabstat(&slabstat);
+

   Can't you perform this check inside get_slabstat()?

[...]

WBR, Sergei