Re: [PATCH] cacheinfo: Keep the old value if of_property_read_u32fails

From: éåæ
Date: Fri Oct 19 2018 - 02:23:45 EST

Hi, Sudeep,

I use MIPS, and there is no "size" in /sys/devices/system/cpu/cpuX/cache/indexX/ file after your patch. Because the DT node only has "next-level-cache = <&L2>;" but has no "size" information.


------------------ Original ------------------
From: "Sudeep Holla"<sudeep.holla@xxxxxxx>;
Date: Thu, Oct 18, 2018 05:15 PM
To: "Huacai Chen"<chenhc@xxxxxxxxxx>;
Cc: "Greg Kroah-Hartman"<gregkh@xxxxxxxxxxxxxxxxxxx>; "Rafael J . Wysocki"<rafael@xxxxxxxxxx>; "LKML"<linux-kernel@xxxxxxxxxxxxxxx>; "zhangfx"<zhangfx@xxxxxxxxxx>; "wuzhangjin"<wuzhangjin@xxxxxxxxx>; "Sudeep Holla"<sudeep.holla@xxxxxxx>;
Subject: Re: [PATCH] cacheinfo: Keep the old value if of_property_read_u32fails

Hi Huacai,

On Thu, Oct 18, 2018 at 09:28:11AM +0800, Huacai Chen wrote:
> Hi, Sudeep,
> Please see this call-graph:
> static int detect_cache_attributes(unsigned int cpu)
> ....
> ret = populate_cache_leaves(cpu);
> ....
> ret = cache_shared_cpu_map_setup(cpu); -->
> cache_setup_of_node() --> cache_of_set_props() -->
> cache_size()/cache_nr_sets
> populate_cache_leaves() is arch-specific, All archs except arm64 have
> provide initial values to cacheinfo:size and cacheinfo:number_of_sets.
> Related files:
> arch/nds32/kernel/cacheinfo.c
> arch/mips/kernel/cacheinfo.c

Only above 2 could be affected, but I want to be sure. I wasn't aware
of MIPS arch setting values elsewhere, assumed DT, my bad.
You have still not answered my question. Which arch are you facing issue ?
Or are you proposing this by code inspection ? I changes look fine, but
want to be sure if the issue you are seeing is in above architectures.