[rds-devel] [RFC net-next 2/3] net: rds: add option for GCOV profiling

[Allison Henderson]

On Thu, 2024-06-06 at 17:36 -0700, allison.henderson at oracle.com wrote:
+cc Chuck Lever, Peter Oberparleiter, Vegard Nossum, rds-devel
> From: Vegard Nossum <vegard.nossum at oracle.com>
> 
> This commit basically implements what ftrace does with
> CONFIG_GCOV_PROFILE_FTRACE for RDS.
> 
> We need this in order to better be able to understand what code paths
> our unit tests are hitting (or not hitting).
> 
> Signed-off-by: Vegard Nossum <vegard.nossum at oracle.com>
> Reviewed-by: Allison Henderson <allison.henderson at oracle.com>
> Reviewed-by: Chuck Lever <chuck.lever at oracle.com>
> Signed-off-by: Allison Henderson <allison.henderson at oracle.com>
> ---
>  net/rds/Kconfig  | 9 +++++++++
>  net/rds/Makefile | 5 +++++
>  2 files changed, 14 insertions(+)
> 
> diff --git a/net/rds/Kconfig b/net/rds/Kconfig
> index 75cd696963b2..f007730aa2bb 100644
> --- a/net/rds/Kconfig
> +++ b/net/rds/Kconfig
> @@ -26,3 +26,12 @@ config RDS_DEBUG
>         bool "RDS debugging messages"
>         depends on RDS
>         default n
> +
> +config GCOV_PROFILE_RDS
> +       bool "Enable GCOV profiling on RDS"
> +       depends on GCOV_KERNEL
> +       help
> +         Enable GCOV profiling on RDS for checking which
> functions/lines
> +         are executed.
> +
> +         If unsure, say N.
> diff --git a/net/rds/Makefile b/net/rds/Makefile
> index 8fdc118e2927..3af1ca1d965c 100644
> --- a/net/rds/Makefile
> +++ b/net/rds/Makefile
> @@ -15,3 +15,8 @@ rds_tcp-y :=          tcp.o tcp_connect.o
> tcp_listen.o tcp_recv.o \
>                         tcp_send.o tcp_stats.o
>  
>  ccflags-$(CONFIG_RDS_DEBUG)    :=      -DRDS_DEBUG
> +
> +# for GCOV coverage profiling
> +ifdef CONFIG_GCOV_PROFILE_RDS
> +GCOV_PROFILE := y
> +endif