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Wed, 26 Aug 2026 23:55:44 -0700 (PDT) Received: from tigeriii.tok.corp.google.com ([2a00:79e0:2031:6:ff0:ad84:24b0:9e52]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-396b0d81682sm1501920a91.7.2026.08.26.23.55.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 Aug 2026 23:55:43 -0700 (PDT) From: Sergey Senozhatsky To: Peter Zijlstra Cc: Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , x86@kernel.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: [RFC PATCH] perf/x86/intel: downgrade alloc_bts_buffer() WARN() to pr_err() Date: Thu, 27 Aug 2026 15:55:10 +0900 Message-ID: <20260827065529.3835720-1-senozhatsky@chromium.org> X-Mailer: git-send-email 2.55.0.897.gb25b4bd76c-goog Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" We see alloc_bts_buffer() allocation failures under memory pressure, while those allocation failures are non-fatal the WARN_ONCE() triggers our fleet monitoring. Given that alloc_bts_buffer() can be called from various paths (e.g. syscall() or kvm_emulate_wrmsr()) and fail multiple times, there seem to be little value in that one single backtrace (for first allocation failure only). Downgrade WARN_ONCE() to pr_err_once(). Signed-off-by: Sergey Senozhatsky --- arch/x86/events/intel/ds.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c index 8940f0292229..29c24b2925a7 100644 --- a/arch/x86/events/intel/ds.c +++ b/arch/x86/events/intel/ds.c @@ -918,7 +918,7 @@ static int alloc_bts_buffer(int cpu) =20 buffer =3D dsalloc_pages(BTS_BUFFER_SIZE, GFP_KERNEL | __GFP_NOWARN, cpu); if (unlikely(!buffer)) { - WARN_ONCE(1, "%s: BTS buffer allocation failure\n", __func__); + pr_err_once(1, "%s: BTS buffer allocation failure\n", __func__); return -ENOMEM; } hwev->ds_bts_vaddr =3D buffer; --=20 2.55.0.897.gb25b4bd76c-goog