ligang/vpp
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

vppinfra: deal with 0 return from os_cpu_clock_frequency()

Browse Source 
Sporadic reports of os_cpu_clock_frequency() returning 0.0 in highly
parallel container environments.

To avoid immediate division by zero:
  Step 1: try estimate_clock_frequency(1e-3).
  Step 2: give up. Pretend we have a 2gHz clock.

Type: fix

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: I19d0fe5259b757ab778599c7026ce485153b43fa
This commit is contained in:
Dave Barach
2020-02-04 16:10:17 -05:00
committed by Damjan Marion
parent a80f8f3717
commit 51cabf2a14
1 changed files with 16 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
src/vppinfra/time.c
View File

@@ -208,6 +208,22 @@ clib_time_init (clib_time_t * c)
{
clib_memset (c, 0, sizeof (c[0]));
c->clocks_per_second = os_cpu_clock_frequency ();
/*
* Sporadic reports of os_cpu_clock_frequency() returning 0.0
* in highly parallel container environments.
* To avoid immediate division by zero:
* Step 1: try estimate_clock_frequency().
* Step 2: give up. Pretend we have a 2gHz clock.
*/
if (PREDICT_FALSE (c->clocks_per_second == 0.0))
{
c->clocks_per_second = estimate_clock_frequency (1e-3);
if (c->clocks_per_second == 0.0)
{
clib_warning ("os_cpu_clock_frequency() returned 0.0, use 2e9...");
c->clocks_per_second = 2e9;
}
}
c->seconds_per_clock = 1 / c->clocks_per_second;
c->log2_clocks_per_second = min_log2_u64 ((u64) c->clocks_per_second);