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x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1655943409; a=rsa-sha256; cv=none; b=mbkqH41v2bFumabqIwbGHGXdGsgjwNhHfQm72rWfPvkw2YKV7BbLX4c5zeEGQcLtLEs/nQ TACvMNITDWvNtBJIdSj6ZabJJc9Yom8/SoXZt+JtC5/lFaliWsLLXfIE8PVp9ChBk9vOqC FmttW33J4DW0GaEtgWXubt0Bp/1vt+4= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=uffvUBvn; spf=pass (imf18.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1655943409; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=dgUKHvNhgtNOXVSQ1fjxb1cCcXKCgmrQGef9fu8AH/w=; b=f8IILl9O1UT9DLKNvAMH5MdetcK90Y1IgrwVE+B5SGpa6qdl4IvjQi5kX0xQr2DNaRtpNg KhhETbbdFspPRyZ4Yl9JVbAvOYTYkG9zmPj5smOq6O3QXUI+p6Yv2pM7nsDFI4cr28KTHD ei+ogA4a8tbQn4YAMStNR7UNlDATCzA= Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=uffvUBvn; spf=pass (imf18.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 7A63F1C0026 X-Stat-Signature: k5nueo4nycj1je99rxzqspswmp9crsio X-Rspam-User: X-HE-Tag: 1655943409-3107 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, 23 Jun 2022 00:05:30 +0000 Yosry Ahmed wrote: > Commit e22c6ed90aa9 ("mm: memcontrol: don't count limit-setting reclaim > as memory pressure") made sure that memory reclaim that is induced by > userspace (limit-setting, proactive reclaim, ..) is not counted as > memory pressure for the purposes of psi. > > Instead of counting psi inside try_to_free_mem_cgroup_pages(), callers > from try_charge() and reclaim_high() wrap the call to > try_to_free_mem_cgroup_pages() with psi handlers. > > However, vmpressure is still counted in these cases where reclaim is > directly induced by userspace. This patch makes sure vmpressure is not > counted in those operations, in the same way as psi. Since vmpressure > calls need to happen deeper within the reclaim path, the same approach > could not be followed. Hence, a new "controlled" flag is added to struct > scan_control to flag a reclaim operation that is controlled by > userspace. This flag is set by limit-setting and proactive reclaim > operations, and is used to count vmpressure correctly. > > To prevent future divergence of psi and vmpressure, commit e22c6ed90aa9 > ("mm: memcontrol: don't count limit-setting reclaim as memory pressure") > is effectively reverted and the same flag is used to control psi as > well. I'll await reviewer input on this, but I can always do trivia! > @@ -3502,6 +3497,8 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, > static int mem_cgroup_force_empty(struct mem_cgroup *memcg) > { > int nr_retries = MAX_RECLAIM_RETRIES; > + unsigned int reclaim_options = MEMCG_RECLAIM_CONTROLLED | > + MEMCG_RECLAIM_MAY_SWAP; If it doesn't fit, it's nicer to do unsigned int reclaim_options; ... reclaim_options = MEMCG_RECLAIM_CONTROLLED | MEMCG_RECLAIM_MAY_SWAP; (several places) > @@ -3751,6 +3757,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order, > .may_writepage = !laptop_mode, > .may_unmap = 1, > .may_swap = 1, > + .controlled = 0, > }; Let's just skip all these initializations to zero, let the compiler take care of it. > @@ -4095,6 +4112,7 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx) > .gfp_mask = GFP_KERNEL, > .order = order, > .may_unmap = 1, > + .controlled = 0, > }; > > set_task_reclaim_state(current, &sc.reclaim_state); > @@ -4555,6 +4573,7 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim) > .may_unmap = 1, > .may_swap = 1, > .hibernation_mode = 1, > + .controlled = 0, > }; > struct zonelist *zonelist = node_zonelist(numa_node_id(), sc.gfp_mask); > unsigned long nr_reclaimed; > @@ -4707,6 +4726,7 @@ static int __node_reclaim(struct pglist_data *pgdat, gfp_t gfp_mask, unsigned in > .may_unmap = !!(node_reclaim_mode & RECLAIM_UNMAP), > .may_swap = 1, > .reclaim_idx = gfp_zone(gfp_mask), > + .controlled = 0, > }; > unsigned long pflags;