From nobody Wed Dec 17 15:34:55 2025 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2B21D1591EE; Tue, 9 Jul 2024 11:42:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720525322; cv=none; b=BX8dJ9s7CcuPRSLoTzo0dq1crOvEkUY8zO58oXYTvXWtGBmI0pivN3HVl9amXtZ2tAnQWzFDgMThnaJ6ZP1OIuTjm1Z50UFSw/Ehym7RPIuNHxoXgV8NKUXeJ3cE3/hIjspOq0qz4CbKgMsijTn9Uw/61fq+41ZfZyY8tRk1oY0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720525322; c=relaxed/simple; bh=s2fhowwMqPJtd8959CM9VSIve/yEDEgfgGO7elOAYPM=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=Ypc6L3ViyLE5YD5eeDKXVezBjtScuamvrIFGmVGPVcESdHBgD0cATMHOp6zWeDPyc5DdWumPDZV9N4K9THBeZzHmRJE08VDqTX6r5wdYQxMj6QhUAuJb+pzOJKKx0kizZQggTXkkxf28QSPvCNLbTO1RvQowvtKMQnn+oYa4+3E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=uj/S9yfl; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=KRgU+Wq3; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="uj/S9yfl"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="KRgU+Wq3" Date: Tue, 09 Jul 2024 11:41:58 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1720525318; h=from:from:sender:sender:reply-to: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; bh=4rn3HpoyNFxDFWcaa9J8PQ6XGMfOEyIfdKE370CbOQ8=; b=uj/S9yflIgkNMtYqNTR2dvdXsw7LpKkROSgZsHLnSfOd30GeMw54DDkhwQNQ2Y4DznfhDg PG/LDRpl5jK5i7bZN8pmjUIhS62ni8J1pYT9PMJv5A30DzIGDsproZdQdPBvsy5NFAQwCk 9LIIOvadsPJnsw14eIB6sQHkefi4CnhaOpQTfv7NWH54oJItc5I+TRrwy2RoE6Uad3xZGZ DQTWMIwU0wew0I0XZQuYLpr4142YX1xm6l1LzAstQD/x2e7W3PGxzvquZGk7anXcde/3r0 xj8uU3BVfNu5lZE840IUk07S6O9nHDb/TvxNsQizEuyx7urvSD41KN5nBqybUw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1720525318; h=from:from:sender:sender:reply-to: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; bh=4rn3HpoyNFxDFWcaa9J8PQ6XGMfOEyIfdKE370CbOQ8=; b=KRgU+Wq39QxDEkOgqmOqhT8bDDAKa6Z2nzNhBpCVTfbf6UjAa+q8DOFTviaKuKWiM160dg TPvl0E/qaj76r2AQ== From: "tip-bot2 for Sebastian Andrzej Siewior" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: perf/core] perf: Shrink the size of the recursion counter. Cc: Sebastian Andrzej Siewior , "Peter Zijlstra (Intel)" , Marco Elver , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20240704170424.1466941-5-bigeasy@linutronix.de> References: <20240704170424.1466941-5-bigeasy@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <172052531830.2215.8399866231682397481.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the perf/core branch of tip: Commit-ID: 5af42f928f3ac555c228740fb4a92d05b19fdd49 Gitweb: https://git.kernel.org/tip/5af42f928f3ac555c228740fb4a92d05b= 19fdd49 Author: Sebastian Andrzej Siewior AuthorDate: Thu, 04 Jul 2024 19:03:38 +02:00 Committer: Peter Zijlstra CommitterDate: Tue, 09 Jul 2024 13:26:35 +02:00 perf: Shrink the size of the recursion counter. There are four recursion counter, one for each context. The type of the counter is `int' but the counter is used as `bool' since it is only incremented if zero. The main goal here is to shrink the whole struct into 32bit int which can later be added task_struct into an existing hole. Reduce the type of the recursion counter to an unsigned char, keep the increment/ decrement operation. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Peter Zijlstra (Intel) Tested-by: Marco Elver Link: https://lore.kernel.org/r/20240704170424.1466941-5-bigeasy@linutronix= .de --- kernel/events/callchain.c | 2 +- kernel/events/core.c | 2 +- kernel/events/internal.h | 4 ++-- 3 files changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index 1273be8..ad57944 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -29,7 +29,7 @@ static inline size_t perf_callchain_entry__sizeof(void) sysctl_perf_event_max_contexts_per_stack)); } =20 -static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]); +static DEFINE_PER_CPU(u8, callchain_recursion[PERF_NR_CONTEXTS]); static atomic_t nr_callchain_events; static DEFINE_MUTEX(callchain_mutex); static struct callchain_cpus_entries *callchain_cpus_entries; diff --git a/kernel/events/core.c b/kernel/events/core.c index 73e1b02..53e2750 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -9765,7 +9765,7 @@ struct swevent_htable { int hlist_refcount; =20 /* Recursion avoidance in each contexts */ - int recursion[PERF_NR_CONTEXTS]; + u8 recursion[PERF_NR_CONTEXTS]; }; =20 static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); diff --git a/kernel/events/internal.h b/kernel/events/internal.h index 386d21c..7f06b79 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -208,7 +208,7 @@ arch_perf_out_copy_user(void *dst, const void *src, uns= igned long n) =20 DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user) =20 -static inline int get_recursion_context(int *recursion) +static inline int get_recursion_context(u8 *recursion) { unsigned char rctx =3D interrupt_context_level(); =20 @@ -221,7 +221,7 @@ static inline int get_recursion_context(int *recursion) return rctx; } =20 -static inline void put_recursion_context(int *recursion, int rctx) +static inline void put_recursion_context(u8 *recursion, int rctx) { barrier(); recursion[rctx]--;