Re: [dpdk-dev] [PATCH] eal: fix parsing of argument of option --lcores

[bynes adam <adambynes@outlook.com>]

On Thu, Jul 21, 2016 at 02:03:38PM +0800, Wei Dai wrote:
Hi Wei,
> The '-' in lcores set overrides cpu set of following
> lcore set in the argument of EAL option --lcores.
> 
> Fixes: 53e54bf81700 ("eal: new option --lcores for cpu assignment")
> 
> Signed-off-by: Wei Dai <wei.dai@intel.com>
> ---
>  lib/librte_eal/common/eal_common_options.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/lib/librte_eal/common/eal_common_options.c b/lib/librte_eal/common/eal_common_options.c
> index 0a594d7..96eb1a9 100644
> --- a/lib/librte_eal/common/eal_common_options.c
> +++ b/lib/librte_eal/common/eal_common_options.c
> @@ -563,6 +563,7 @@ convert_to_cpuset(rte_cpuset_t *cpusetp,
>   * lcores, cpus could be a single digit/range or a group.
>   * '(' and ')' are necessary if it's a group.
>   * If not supply '@cpus', the value of cpus uses the same as lcores.
> + * The 'a-b' in lcores not within '(' and ')' means a,a+1,...,b-1,b .
this description is not very clear, a-b and (a-b) are both the same meaning.
may be need a table for comparison
a-b@(c-d)
a-b@c-d
(a-b)@c-d
(a-b)@(c-d)
all the above I believe are the same
only the following two cases:
a-b,
(a-b),
so the key point here is the @ and (), not only @
>   * e.g. '1,2@(5-7),(3-5)@(0,2),(0,6),7-8' means start 9 EAL thread as below
>   *   lcore 0 runs on cpuset 0x41 (cpu 0,6)
>   *   lcore 1 runs on cpuset 0x2 (cpu 1)
> @@ -571,6 +572,15 @@ convert_to_cpuset(rte_cpuset_t *cpusetp,
>   *   lcore 6 runs on cpuset 0x41 (cpu 0,6)
>   *   lcore 7 runs on cpuset 0x80 (cpu 7)
>   *   lcore 8 runs on cpuset 0x100 (cpu 8)
> + * e.g. '0-2,(3-5)@(3,4),6@(5,6),7@(5-7)'means start 8 EAL threads as below
> + *   lcore 0 runs on cpuset 0x1 (cpu 0)
> + *   lcore 1 runs on cpuset 0x2 (cpu 1)
> + *   lcore 2 runs on cpuset ox4 (cpu 2)
> + *   lcore 3,4,5 runs on cpuset 0x18 (cpu 3,4)
> + *   lcore 6 runs on cpuset 0x60 (cpu 5,6)
> + *   lcore 7 runs on cpuset 0xe0 (cpu 5,6,7)
> + * The second case is used to test bugfix for lflags not be cleared after use
you can put this sentance and description into the commit log
I don't think you should put bugfix description in comments here.
> + */
>   */
>  static int
>  eal_parse_lcores(const char *lcores)
> @@ -679,6 +689,8 @@ eal_parse_lcores(const char *lcores)
>  				   sizeof(rte_cpuset_t));
>  		}
>  
> +		lflags = 0;
> +
>  		lcores = end + 1;
>  	} while (*end != '\0');
>  
> -- 
> 2.5.5
Adam Bynes