linux-kernel - Re: [PATCH v2] mm, tracing: improve rss

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Wed, 10 Mar 2021 12:43:01 -0500
From:   Steven Rostedt <rostedt@...dmis.org>
To:     Ovidiu Panait <ovidiu.panait@...driver.com>
Cc:     linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
        mingo@...hat.com, christian@...uner.io
Subject: Re: [PATCH v2] mm, tracing: improve rss_stat tracepoint message

On Wed, 10 Mar 2021 18:23:05 +0200
Ovidiu Panait <ovidiu.panait@...driver.com> wrote:

> Adjust the rss_stat tracepoint to print the name of the resident page type
> that got updated (e.g. MM_ANONPAGES/MM_FILEPAGES), rather than the numeric
> index corresponding to it (the __entry->member value):
> 
> Before this patch:
> ------------------
> rss_stat: mm_id=1216113068 curr=0 member=1 size=28672B
> rss_stat: mm_id=1216113068 curr=0 member=1 size=0B
> rss_stat: mm_id=534402304 curr=1 member=0 size=188416B
> rss_stat: mm_id=534402304 curr=1 member=1 size=40960B
> 
> After this patch:
> -----------------
> rss_stat: mm_id=1726253524 curr=1 type=MM_ANONPAGES size=40960B
> rss_stat: mm_id=1726253524 curr=1 type=MM_FILEPAGES size=663552B
> rss_stat: mm_id=1726253524 curr=1 type=MM_ANONPAGES size=65536B
> rss_stat: mm_id=1726253524 curr=1 type=MM_FILEPAGES size=647168B
> 
> Use TRACE_DEFINE_ENUM()/__print_symbolic() logic to map the enum values to
> the strings they represent, so that userspace tools can also parse the raw
> data correctly.
> 
> Signed-off-by: Ovidiu Panait <ovidiu.panait@...driver.com>
> Signed-off-by: Steven Rostedt <rostedt@...dmis.org>

You can change that to:

Suggested-by: Steven Rostedt (VMware) <rostedt@...dmis.org>

And

Reviewed-by: Steven Rostedt (VMware) <rostedt@...dmis.org>

Thanks!

-- Steve

> ---
> v2: - rework the patch so that user space tools can parse the raw
>       data correctly
> 
>  include/trace/events/kmem.h | 24 ++++++++++++++++++++++--
>  1 file changed, 22 insertions(+), 2 deletions(-)
> 
> diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h
> index 3a60b6b6db32..829a75692cc0 100644
> --- a/include/trace/events/kmem.h
> +++ b/include/trace/events/kmem.h
> @@ -343,6 +343,26 @@ static unsigned int __maybe_unused mm_ptr_to_hash(const void *ptr)
>  #define __PTR_TO_HASHVAL
>  #endif
>  
> +#define TRACE_MM_PAGES		\
> +	EM(MM_FILEPAGES)	\
> +	EM(MM_ANONPAGES)	\
> +	EM(MM_SWAPENTS)		\
> +	EMe(MM_SHMEMPAGES)
> +
> +#undef EM
> +#undef EMe
> +
> +#define EM(a)	TRACE_DEFINE_ENUM(a);
> +#define EMe(a)	TRACE_DEFINE_ENUM(a);
> +
> +TRACE_MM_PAGES
> +
> +#undef EM
> +#undef EMe
> +
> +#define EM(a)	{ a, #a },
> +#define EMe(a)	{ a, #a }
> +
>  TRACE_EVENT(rss_stat,
>  
>  	TP_PROTO(struct mm_struct *mm,
> @@ -365,10 +385,10 @@ TRACE_EVENT(rss_stat,
>  		__entry->size = (count << PAGE_SHIFT);
>  	),
>  
> -	TP_printk("mm_id=%u curr=%d member=%d size=%ldB",
> +	TP_printk("mm_id=%u curr=%d type=%s size=%ldB",
>  		__entry->mm_id,
>  		__entry->curr,
> -		__entry->member,
> +		__print_symbolic(__entry->member, TRACE_MM_PAGES),
>  		__entry->size)
>  	);
>  #endif /* _TRACE_KMEM_H */