Messages in this thread | | | From | Kay Sievers <> | Date | Thu, 19 Jul 2012 11:38:57 +0200 | Subject | Re: [PATCH] printk: Export struct log size and member offsets through vmcoreinfo |
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On Wed, Jul 18, 2012 at 7:56 PM, Vivek Goyal <vgoyal@redhat.com> wrote: > On Wed, Jul 18, 2012 at 07:27:08PM +0200, Kay Sievers wrote: >> On Wed, Jul 18, 2012 at 7:18 PM, Vivek Goyal <vgoyal@redhat.com> wrote: >> >> > Currently I am not exporting log "level" info as that is a bitfield and >> > offsetof() bitfields can't be calculated. >> >> We could make the level the lower 3 bits of the byte, export the byte, >> and define that only 3 bits of the byte are valid? Would that help? > > Yes, that should work. Here is the prototype patch which stores 5 bits > of flag and 3 bits of level in a byte. I have not tested it yet, but > if you like the approach, I will test it.
> - u8 flags:5; /* internal record flags */ > - u8 level:3; /* syslog level */ > + u8 flags_level; /* 5 bit internal record flags, 3 bits syslog
Looks ok.
If we would swap the 5 + 3 bit field byte declaration, and add __packed, we can still not rely on the level to be consistently the lower 3 bits of the byte, right?
Thanks, Kay
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