From: akpm@linux-foundation.org
To: andreyknvl@google.com, aryabinin@virtuozzo.com,
dvyukov@google.com, james.morse@arm.com, keescook@chromium.org,
nicstange@gmail.com, quentin.casasnovas@oracle.com,
vegard.nossum@oracle.com, mm-commits@vger.kernel.org
Subject: [merged] kcov-properly-check-if-we-are-in-an-interrupt.patch removed from -mm tree
Date: Fri, 28 Oct 2016 11:30:13 -0700 [thread overview]
Message-ID: <58139935.y4qwoLpJCLyyrtao%akpm@linux-foundation.org> (raw)
The patch titled
Subject: kcov: properly check if we are in an interrupt
has been removed from the -mm tree. Its filename was
kcov-properly-check-if-we-are-in-an-interrupt.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Andrey Konovalov <andreyknvl@google.com>
Subject: kcov: properly check if we are in an interrupt
in_interrupt() returns a nonzero value when we are either in an
interrupt or have bh disabled via local_bh_disable(). Since we are
interested in only ignoring coverage from actual interrupts, do a
proper check instead of just calling in_interrupt().
As a result of this change, kcov will start to collect coverage from
within local_bh_disable()/local_bh_enable() sections.
Link: http://lkml.kernel.org/r/1476115803-20712-1-git-send-email-andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Nicolai Stange <nicstange@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: James Morse <james.morse@arm.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
kernel/kcov.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff -puN kernel/kcov.c~kcov-properly-check-if-we-are-in-an-interrupt kernel/kcov.c
--- a/kernel/kcov.c~kcov-properly-check-if-we-are-in-an-interrupt
+++ a/kernel/kcov.c
@@ -53,8 +53,15 @@ void notrace __sanitizer_cov_trace_pc(vo
/*
* We are interested in code coverage as a function of a syscall inputs,
* so we ignore code executed in interrupts.
+ * The checks for whether we are in an interrupt are open-coded, because
+ * 1. We can't use in_interrupt() here, since it also returns true
+ * when we are inside local_bh_disable() section.
+ * 2. We don't want to use (in_irq() | in_serving_softirq() | in_nmi()),
+ * since that leads to slower generated code (three separate tests,
+ * one for each of the flags).
*/
- if (!t || in_interrupt())
+ if (!t || (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_OFFSET
+ | NMI_MASK)))
return;
mode = READ_ONCE(t->kcov_mode);
if (mode == KCOV_MODE_TRACE) {
_
Patches currently in -mm which might be from andreyknvl@google.com are
reply other threads:[~2016-10-28 18:30 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=58139935.y4qwoLpJCLyyrtao%akpm@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=andreyknvl@google.com \
--cc=aryabinin@virtuozzo.com \
--cc=dvyukov@google.com \
--cc=james.morse@arm.com \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mm-commits@vger.kernel.org \
--cc=nicstange@gmail.com \
--cc=quentin.casasnovas@oracle.com \
--cc=vegard.nossum@oracle.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.