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Date: Sat, 23 Nov 2024 17:01:57 +0000
From: Matthew Wilcox <willy@infradead.org>
To: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Michal Hocko <mhocko@kernel.org>,
	Roman Gushchin <roman.gushchin@linux.dev>,
	Muchun Song <muchun.song@linux.dev>,
	Vlastimil Babka <vbabka@suse.cz>,
	Axel Rasmussen <axelrasmussen@google.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Suren Baghdasaryan <surenb@google.com>, linux-mm@kvack.org,
	cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
	Meta kernel team <kernel-team@meta.com>
Subject: Re: [PATCH] mm: mmap_lock: optimize mmap_lock tracepoints
Message-ID: <Z0IKhWfOr4ppnQem@casper.infradead.org>
References: <20241123060939.169978-1-shakeel.butt@linux.dev>
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In-Reply-To: <20241123060939.169978-1-shakeel.butt@linux.dev>

On Fri, Nov 22, 2024 at 10:09:39PM -0800, Shakeel Butt wrote:
>  	TP_printk(
> -		"mm=%p memcg_path=%s write=%s",
> -		__entry->mm,
> -		__get_str(memcg_path),
> +		"mm=%p memcg_id=%llu write=%s",
> +		__entry->mm, __entry->memcg_id,
>  		__entry->write ? "true" : "false"

Is it actually useful to print out the (hashed) pointer of the mm?
Wouldn't the PID be more useful so you could actually associate it with
a task?