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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250807075810.358714-5-urezki@gmail.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 4D90B40002 X-Stat-Signature: ek8nwajdtcxxye4as3i56ubpc66pcs6i X-Rspam-User: X-HE-Tag: 1755483266-197302 X-HE-Meta: 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 Ufh7DB71 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 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: List-Subscribe: List-Unsubscribe: On 08/07/25 at 09:58am, Uladzislau Rezki (Sony) wrote: > The vm_area_alloc_pages() function uses cond_resched() to yield the > CPU during potentially long-running loops. However, these loops are > not considered long-running under normal conditions. In non-blocking > contexts, calling cond_resched() is inappropriate also. > > Remove these calls to ensure correctness for blocking/non-blocking > contexts. This also simplifies the code path. In fact, a slow path > of page allocator already includes reschedule points to mitigate > latency. > > This patch was tested for !CONFIG_PREEMPT kernel and with large > allocation chunks(~1GB), without triggering any "BUG: soft lockup" > warnings. > > Signed-off-by: Uladzislau Rezki (Sony) > --- > mm/vmalloc.c | 2 -- > 1 file changed, 2 deletions(-) Reviewed-by: Baoquan He > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 81b6d3bde719..b0255e0c74b3 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -3633,7 +3633,6 @@ vm_area_alloc_pages(gfp_t gfp, int nid, > pages + nr_allocated); > > nr_allocated += nr; > - cond_resched(); > > /* > * If zero or pages were obtained partly, > @@ -3675,7 +3674,6 @@ vm_area_alloc_pages(gfp_t gfp, int nid, > for (i = 0; i < (1U << order); i++) > pages[nr_allocated + i] = page + i; > > - cond_resched(); > nr_allocated += 1U << order; > } > > -- > 2.39.5 >