From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:60836 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728235AbgIRCJH (ORCPT ); Thu, 17 Sep 2020 22:09:07 -0400 From: Sasha Levin Subject: [PATCH AUTOSEL 4.19 054/206] s390/cpum_sf: Use kzalloc and minor changes Date: Thu, 17 Sep 2020 22:05:30 -0400 Message-Id: <20200918020802.2065198-54-sashal@kernel.org> In-Reply-To: <20200918020802.2065198-1-sashal@kernel.org> References: <20200918020802.2065198-1-sashal@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit List-ID: To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Thomas Richter , Vasily Gorbik , Sasha Levin , linux-s390@vger.kernel.org From: Thomas Richter [ Upstream commit 32dab6828c42f087439d3e2617dc7283546bd8f7 ] Use kzalloc() to allocate auxiliary buffer structure initialized with all zeroes to avoid random value in trace output. Avoid double access to SBD hardware flags. Signed-off-by: Thomas Richter Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin --- arch/s390/kernel/perf_cpum_sf.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c index 74a296cea21cc..0e6d01225a670 100644 --- a/arch/s390/kernel/perf_cpum_sf.c +++ b/arch/s390/kernel/perf_cpum_sf.c @@ -1377,8 +1377,8 @@ static int aux_output_begin(struct perf_output_handle *handle, idx = aux->empty_mark + 1; for (i = 0; i < range_scan; i++, idx++) { te = aux_sdb_trailer(aux, idx); - te->flags = te->flags & ~SDB_TE_BUFFER_FULL_MASK; - te->flags = te->flags & ~SDB_TE_ALERT_REQ_MASK; + te->flags &= ~(SDB_TE_BUFFER_FULL_MASK | + SDB_TE_ALERT_REQ_MASK); te->overflow = 0; } /* Save the position of empty SDBs */ @@ -1425,8 +1425,7 @@ static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index, te = aux_sdb_trailer(aux, alert_index); do { orig_flags = te->flags; - orig_overflow = te->overflow; - *overflow = orig_overflow; + *overflow = orig_overflow = te->overflow; if (orig_flags & SDB_TE_BUFFER_FULL_MASK) { /* * SDB is already set by hardware. @@ -1660,7 +1659,7 @@ static void *aux_buffer_setup(struct perf_event *event, void **pages, } /* Allocate aux_buffer struct for the event */ - aux = kmalloc(sizeof(struct aux_buffer), GFP_KERNEL); + aux = kzalloc(sizeof(struct aux_buffer), GFP_KERNEL); if (!aux) goto no_aux; sfb = &aux->sfb; -- 2.25.1