[lttng-dev] LTTng and multiple kernels

[lttng-dev] LTTng and multiple kernels

[Thibault, Daniel]

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   Assume we have this system with a choice of kernels at boot time (for instance, between 2.6.18, 2.6.18-128.el5, and 2.6.18-grsec).  Do we need to do multiple LTTng builds?  For some packages only, maybe (e.g., lttng-modules)?  If so, can they cohabit without trouble, or will we need to run some sort of LTTng-fixing script every time we switch kernels?

Daniel U. Thibault, M.Sc.²

Informaticien scientifique, CME-PSC, Centre de recherches de Valcartier
Recherche et développement pour la défense Canada / Gouvernement du Canada
daniel.thibault at drdc-rddc.gc.ca / Tél: 418-844-4000x4245 Téléc: 418-844-4538
daniel.thibault at forces.gc.ca / Tél: 418-844-4000x4245 Téléc: 418-844-4538

Computer Scientist, MCCS-SPC, Valcartier Research Centre 
Defence Research and Development Canada / Government of Canada
daniel.thibault at drdc-rddc.gc.ca / Tel: 418-844-4000x4245 Fax: 418-844-4538
daniel.thibault at forces.gc.ca / Tel: 418-844-4000x4245 Fax: 418-844-4538

DRDC is an agency of the Department of National Defence / RDDC est une agence du ministère de la Défense nationale

[lttng-dev] LTTng and multiple kernels

[Mathieu Desnoyers]

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You will then need to build and install lttng-modules against each of your
kernels.

lttng-modules (as any kernel module) installs under /lib/modules/$(uname -r),
where $(uname -r) evaluates to the kernel version you build against.

When building, it looks for your kernel headers by following /lib/modules/$(uname -r)/build
or /lib/modules/$(uname -r)/source (I don't recall which).

You can override the directory it builds against by using the KERNELDIR environment
variable.

Thanks,

Mathieu

----- On Oct 12, 2016, at 4:31 PM, Daniel Thibault Daniel.Thibault at drdc-rddc.gc.ca wrote:

> Assume we have this system with a choice of kernels at boot time (for instance,
> between 2.6.18, 2.6.18-128.el5, and 2.6.18-grsec).  Do we need to do multiple
> LTTng builds?  For some packages only, maybe (e.g., lttng-modules)?  If so, can
> they cohabit without trouble, or will we need to run some sort of LTTng-fixing
> script every time we switch kernels?
> 
> Daniel U. Thibault, M.Sc.²
> 
> Informaticien scientifique, CME-PSC, Centre de recherches de Valcartier
> Recherche et développement pour la défense Canada / Gouvernement du Canada
> daniel.thibault at drdc-rddc.gc.ca / Tél: 418-844-4000x4245 Téléc: 418-844-4538
> daniel.thibault at forces.gc.ca / Tél: 418-844-4000x4245 Téléc: 418-844-4538
> 
> Computer Scientist, MCCS-SPC, Valcartier Research Centre
> Defence Research and Development Canada / Government of Canada
> daniel.thibault at drdc-rddc.gc.ca / Tel: 418-844-4000x4245 Fax: 418-844-4538
> daniel.thibault at forces.gc.ca / Tel: 418-844-4000x4245 Fax: 418-844-4538
> 
> DRDC is an agency of the Department of National Defence / RDDC est une agence du
> ministère de la Défense nationale
> _______________________________________________
> lttng-dev mailing list
> lttng-dev at lists.lttng.org
> https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com