[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH 5/6] xenbus: process be_watch events in xenwatch multithreading


  • To: Dongli Zhang <dongli.zhang@xxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx
  • From: Juergen Gross <jgross@xxxxxxxx>
  • Date: Fri, 14 Sep 2018 16:26:37 +0200
  • Autocrypt: addr=jgross@xxxxxxxx; prefer-encrypt=mutual; keydata= xsBNBFOMcBYBCACgGjqjoGvbEouQZw/ToiBg9W98AlM2QHV+iNHsEs7kxWhKMjrioyspZKOB ycWxw3ie3j9uvg9EOB3aN4xiTv4qbnGiTr3oJhkB1gsb6ToJQZ8uxGq2kaV2KL9650I1SJve dYm8Of8Zd621lSmoKOwlNClALZNew72NjJLEzTalU1OdT7/i1TXkH09XSSI8mEQ/ouNcMvIJ NwQpd369y9bfIhWUiVXEK7MlRgUG6MvIj6Y3Am/BBLUVbDa4+gmzDC9ezlZkTZG2t14zWPvx XP3FAp2pkW0xqG7/377qptDmrk42GlSKN4z76ELnLxussxc7I2hx18NUcbP8+uty4bMxABEB AAHNHkp1ZXJnZW4gR3Jvc3MgPGpncm9zc0BzdXNlLmRlPsLAeQQTAQIAIwUCU4xw6wIbAwcL CQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJELDendYovxMvi4UH/Ri+OXlObzqMANruTd4N zmVBAZgx1VW6jLc8JZjQuJPSsd/a+bNr3BZeLV6lu4Pf1Yl2Log129EX1KWYiFFvPbIiq5M5 kOXTO8Eas4CaScCvAZ9jCMQCgK3pFqYgirwTgfwnPtxFxO/F3ZcS8jovza5khkSKL9JGq8Nk czDTruQ/oy0WUHdUr9uwEfiD9yPFOGqp4S6cISuzBMvaAiC5YGdUGXuPZKXLpnGSjkZswUzY d9BVSitRL5ldsQCg6GhDoEAeIhUC4SQnT9SOWkoDOSFRXZ+7+WIBGLiWMd+yKDdRG5RyP/8f 3tgGiB6cyuYfPDRGsELGjUaTUq3H2xZgIPfOwE0EU4xwFgEIAMsx+gDjgzAY4H1hPVXgoLK8 B93sTQFN9oC6tsb46VpxyLPfJ3T1A6Z6MVkLoCejKTJ3K9MUsBZhxIJ0hIyvzwI6aYJsnOew cCiCN7FeKJ/oA1RSUemPGUcIJwQuZlTOiY0OcQ5PFkV5YxMUX1F/aTYXROXgTmSaw0aC1Jpo w7Ss1mg4SIP/tR88/d1+HwkJDVW1RSxC1PWzGizwRv8eauImGdpNnseneO2BNWRXTJumAWDD pYxpGSsGHXuZXTPZqOOZpsHtInFyi5KRHSFyk2Xigzvh3b9WqhbgHHHE4PUVw0I5sIQt8hJq 5nH5dPqz4ITtCL9zjiJsExHuHKN3NZsAEQEAAcLAXwQYAQIACQUCU4xwFgIbDAAKCRCw3p3W KL8TL0P4B/9YWver5uD/y/m0KScK2f3Z3mXJhME23vGBbMNlfwbr+meDMrJZ950CuWWnQ+d+ Ahe0w1X7e3wuLVODzjcReQ/v7b4JD3wwHxe+88tgB9byc0NXzlPJWBaWV01yB2/uefVKryAf AHYEd0gCRhx7eESgNBe3+YqWAQawunMlycsqKa09dBDL1PFRosF708ic9346GLHRc6Vj5SRA UTHnQqLetIOXZm3a2eQ1gpQK9MmruO86Vo93p39bS1mqnLLspVrL4rhoyhsOyh0Hd28QCzpJ wKeHTd0MAWAirmewHXWPco8p1Wg+V+5xfZzuQY0f4tQxvOpXpt4gQ1817GQ5/Ed/wsDtBBgB CAAgFiEEhRJncuj2BJSl0Jf3sN6d1ii/Ey8FAlrd8NACGwIAgQkQsN6d1ii/Ey92IAQZFggA HRYhBFMtsHpB9jjzHji4HoBcYbtP2GO+BQJa3fDQAAoJEIBcYbtP2GO+TYsA/30H/0V6cr/W V+J/FCayg6uNtm3MJLo4rE+o4sdpjjsGAQCooqffpgA+luTT13YZNV62hAnCLKXH9n3+ZAgJ RtAyDWk1B/0SMDVs1wxufMkKC3Q/1D3BYIvBlrTVKdBYXPxngcRoqV2J77lscEvkLNUGsu/z W2pf7+P3mWWlrPMJdlbax00vevyBeqtqNKjHstHatgMZ2W0CFC4hJ3YEetuRBURYPiGzuJXU pAd7a7BdsqWC4o+GTm5tnGrCyD+4gfDSpkOT53S/GNO07YkPkm/8J4OBoFfgSaCnQ1izwgJQ jIpcG2fPCI2/hxf2oqXPYbKr1v4Z1wthmoyUgGN0LPTIm+B5vdY82wI5qe9uN6UOGyTH2B3p hRQUWqCwu2sqkI3LLbTdrnyDZaixT2T0f4tyF5Lfs+Ha8xVMhIyzNb1byDI5FKCb
  • Cc: wei.liu2@xxxxxxxxxx, konrad.wilk@xxxxxxxxxx, srinivas.eeda@xxxxxxxxxx, paul.durrant@xxxxxxxxxx, boris.ostrovsky@xxxxxxxxxx, roger.pau@xxxxxxxxxx
  • Delivery-date: Fri, 14 Sep 2018 14:26:50 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
  • Openpgp: preference=signencrypt

On 14/09/18 16:18, Dongli Zhang wrote:
> Hi Juergen,
> 
> On 09/14/2018 05:12 PM, Juergen Gross wrote:
>> On 14/09/18 09:34, Dongli Zhang wrote:
>>> This is the 5th patch of a (6-patch) patch set.
>>>
>>> With this patch, watch event in relative path pattern
>>> 'backend/<pvdev>/<domid>i/...' can be processed in per-domU xenwatch
>>
>> superfluous "i" ----------^
>>
>>> thread.
>>>
>>> Signed-off-by: Dongli Zhang <dongli.zhang@xxxxxxxxxx>
>>> ---
>>>  drivers/xen/xenbus/xenbus_probe.c         |  2 +-
>>>  drivers/xen/xenbus/xenbus_probe_backend.c | 32 
>>> +++++++++++++++++++++++++++++++
>>>  include/xen/xenbus.h                      |  2 ++
>>>  3 files changed, 35 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/xen/xenbus/xenbus_probe.c 
>>> b/drivers/xen/xenbus/xenbus_probe.c
>>> index ba0644c..aa1b15a 100644
>>> --- a/drivers/xen/xenbus/xenbus_probe.c
>>> +++ b/drivers/xen/xenbus/xenbus_probe.c
>>> @@ -552,7 +552,7 @@ int xenbus_probe_devices(struct xen_bus_type *bus)
>>>  }
>>>  EXPORT_SYMBOL_GPL(xenbus_probe_devices);
>>>  
>>> -static unsigned int char_count(const char *str, char c)
>>> +unsigned int char_count(const char *str, char c)
>>
>> Please change the name of the function when making it globally
>> visible, e.g. by prefixing "xenbus_".
>>
>> Generally I think you don't need to use it below.
>>
>>>  {
>>>     unsigned int i, ret = 0;
>>>  
>>> diff --git a/drivers/xen/xenbus/xenbus_probe_backend.c 
>>> b/drivers/xen/xenbus/xenbus_probe_backend.c
>>> index b0bed4f..50df86a 100644
>>> --- a/drivers/xen/xenbus/xenbus_probe_backend.c
>>> +++ b/drivers/xen/xenbus/xenbus_probe_backend.c
>>> @@ -211,9 +211,41 @@ static void backend_changed(struct xenbus_watch *watch,
>>>     xenbus_dev_changed(path, &xenbus_backend);
>>>  }
>>>  
>>> +static domid_t path_to_domid(const char *path)
>>> +{
>>> +   const char *p = path;
>>> +   domid_t domid = 0;
>>> +
>>> +   while (*p) {
>>> +           if (*p < '0' || *p > '9')
>>> +                   break;
>>> +           domid = (domid << 3) + (domid << 1) + (*p - '0');
>>
>> reinventing atoi()?
>>
>> Please don't do that. kstrtou16() seems to be a perfect fit.
> 
> I did use kstrtou*() in the early prototype and realized kstrtou16() returns 0
> if the input string contains non-numerical characters.
> 
> E.g., the example of input can be "1/0/state", where 1 is fotherend_id
> (frontend_id) and 0 is handle.
> 
> When "1/0/state" is used at input, kstrtou16() returns 0 (returned integer) 
> and
> -22 (error).

Aah, okay. Then simple_strtoul()?


Juergen

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.