kernel: only strip proc for small flash devices

Currently, you are not able to get statistics about IPv4 and IPv6
usage. This information can be collected via the snmp and snmp6.
However, in the current state this interface is disabled as you can
read in the "902-debloat_proc.patch":
 "Strip non-essential /proc functionality to reduce code size"

Tools like netstat use the snmp/6 interface to collect interface
statistics. Some prometheus exporters also mention this:
- prometheus-collectors/netstat.lua
- prometheus-collectors/snmp6 (still a PR)
- collectd/snmp6 (still a PR)

PRs:
- https://github.com/collectd/collectd/pull/3789
- https://github.com/openwrt/packages/pull/14158

Instead of enabling it as default for all devices we condition it
 default y if SMALL_FLASH

A test shows it needs around 16 kiB.

Signed-off-by: Nick Hainke <vincent@systemli.org>
[fixed whitespace issue]
Signed-off-by: Petr Štetiar <ynezz@true.cz>

diff --git a/config/Config-kernel.in b/config/Config-kernel.in
index c9efed84d3f53ba0d328017a788d21f94ff301ca..e22fcf63826cb368581bfc574a9b3f5d0817f706 100644 (file)
--- a/config/Config-kernel.in
+++ b/config/Config-kernel.in
@@ -35,6 +35,10 @@ config KERNEL_SWAP
        bool "Support for paging of anonymous memory (swap)"
        default y if !SMALL_FLASH
 
+config KERNEL_PROC_STRIPPED
+       bool "Strip non-essential /proc functionality to reduce code size"
+       default y if SMALL_FLASH
+
 config KERNEL_DEBUG_FS
        bool "Compile the kernel with debug filesystem enabled"
        default y
@@ -376,7 +380,7 @@ config KERNEL_AIO
 config KERNEL_IO_URING
        bool "Compile the kernel with io_uring support"
        default y if !SMALL_FLASH
-       depends on LINUX_5_4 
+       depends on LINUX_5_4
 
 config KERNEL_FHANDLE
        bool "Compile the kernel with support for fhandle syscalls"

diff --git a/target/linux/generic/config-5.4 b/target/linux/generic/config-5.4
index 00fbd93ff41d1d44d5937b3941ec209693539940..8473817000d880bfb298acfcebccd3de596c4b82 100644 (file)
--- a/target/linux/generic/config-5.4
+++ b/target/linux/generic/config-5.4
@@ -4123,7 +4123,6 @@ CONFIG_PRINT_STACK_DEPTH=64
 CONFIG_PROC_FS=y
 # CONFIG_PROC_KCORE is not set
 # CONFIG_PROC_PAGE_MONITOR is not set
-CONFIG_PROC_STRIPPED=y
 CONFIG_PROC_SYSCTL=y
 # CONFIG_PROC_VMCORE_DEVICE_DUMP is not set
 # CONFIG_PROFILE_ALL_BRANCHES is not set