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DNSWL_BLOCKED(0.00)[2a07:de40:b281:104:10:150:64:97:from,2a07:de40:b281:106:10:150:64:167:received]; RCPT_COUNT_SEVEN(0.00)[11]; MID_RHS_MATCH_FROM(0.00)[]; DKIM_TRACE(0.00)[suse.cz:+]; RCVD_VIA_SMTP_AUTH(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo] X-Spam-Score: -4.51 On 8/28/25 10:47, Yueyang Pan wrote: > On Thu, Aug 28, 2025 at 10:41:23AM +0200, Vlastimil Babka wrote: >> On 8/28/25 10:34, Yueyang Pan wrote: >> > On Wed, Aug 27, 2025 at 03:06:19PM -0700, Andrew Morton wrote: >> >> On Wed, 27 Aug 2025 11:34:23 -0700 Yueyang Pan wrote: >> >> >> >> > In production, show_mem() can be called concurrently from two >> >> > different entities, for example one from oom_kill_process() >> >> > another from __alloc_pages_slowpath from another kthread. This >> >> > patch adds a mutex and invokes trylock before printing out the >> >> > kernel alloc info in show_mem(). This way two alloc info won't >> >> > interleave with each other, which then makes parsing easier. >> >> What about the rest of the information printed by show_mem() being interleaved? > > Thanks for your feedback, Vlastimil. We cannot use trylock for the rest > part as node filter can be different. Right. > Do you think we need a lock to prevent the whole show_mem() from being > interleaved and to acquire it at the very beginning? Will it be too > heavy? It might be risky so perhaps let's not. Guess we can disentangle by dmesg showing the thread id prefix.