From: Jeremy Fitzhardinge <jeremy@goop.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
"Nick Piggin" <npiggin@kernel.dk>,
"Mathieu Desnoyers" <mathieu.desnoyers@polymtl.ca>,
"Américo Wang" <xiyou.wangcong@gmail.com>,
"Eric Dumazet" <dada1@cosmosbay.com>,
"Jan Beulich" <JBeulich@novell.com>,
"Avi Kivity" <avi@redhat.com>,
Xen-devel <xen-devel@lists.xensource.com>,
"H. Peter Anvin" <hpa@zytor.com>,
"Linux Virtualization"
<virtualization@lists.linux-foundation.org>,
"Srivatsa Vaddagiri" <vatsa@linux.vnet.ibm.com>,
"Jeremy Fitzhardinge" <jeremy.fitzhardinge@citrix.com>
Subject: [PATCH 10/14] x86/pvticketlock: use callee-save for lock_spinning
Date: Tue, 16 Nov 2010 13:08:41 -0800 [thread overview]
Message-ID: <598aba88fd8411b063884264e1521e8e64b3cb15.1289940821.git.jeremy.fitzhardinge@citrix.com> (raw)
In-Reply-To: <cover.1289940821.git.jeremy.fitzhardinge@citrix.com>
In-Reply-To: <cover.1289940821.git.jeremy.fitzhardinge@citrix.com>
From: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Although the lock_spinning calls in the spinlock code are on the
uncommon path, their presence can cause the compiler to generate many
more register save/restores in the function pre/postamble, which is in
the fast path. To avoid this, convert it to using the pvops callee-save
calling convention, which defers all the save/restores until the actual
function is called, keeping the fastpath clean.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
---
arch/x86/include/asm/paravirt.h | 2 +-
arch/x86/include/asm/paravirt_types.h | 2 +-
arch/x86/kernel/paravirt-spinlocks.c | 2 +-
arch/x86/xen/spinlock.c | 3 ++-
4 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index c864775..6f275ca 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -719,7 +719,7 @@ static inline void __set_fixmap(unsigned /* enum fixed_addresses */ idx,
static inline void __ticket_lock_spinning(struct arch_spinlock *lock, unsigned ticket)
{
- PVOP_VCALL2(pv_lock_ops.lock_spinning, lock, ticket);
+ PVOP_VCALLEE2(pv_lock_ops.lock_spinning, lock, ticket);
}
static inline void ____ticket_unlock_kick(struct arch_spinlock *lock, unsigned ticket)
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index 1078474..53f249a 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -315,7 +315,7 @@ struct pv_mmu_ops {
struct arch_spinlock;
struct pv_lock_ops {
- void (*lock_spinning)(struct arch_spinlock *lock, unsigned ticket);
+ struct paravirt_callee_save lock_spinning;
void (*unlock_kick)(struct arch_spinlock *lock, unsigned ticket);
};
diff --git a/arch/x86/kernel/paravirt-spinlocks.c b/arch/x86/kernel/paravirt-spinlocks.c
index c2e010e..4251c1d 100644
--- a/arch/x86/kernel/paravirt-spinlocks.c
+++ b/arch/x86/kernel/paravirt-spinlocks.c
@@ -9,7 +9,7 @@
struct pv_lock_ops pv_lock_ops = {
#ifdef CONFIG_SMP
- .lock_spinning = paravirt_nop,
+ .lock_spinning = __PV_IS_CALLEE_SAVE(paravirt_nop),
.unlock_kick = paravirt_nop,
#endif
};
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 5feb897..c31c5a3 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -137,6 +137,7 @@ out:
w->lock = NULL;
spin_time_accum_blocked(start);
}
+PV_CALLEE_SAVE_REGS_THUNK(xen_lock_spinning);
static void xen_unlock_kick(struct arch_spinlock *lock, unsigned next)
{
@@ -189,7 +190,7 @@ void xen_uninit_lock_cpu(int cpu)
void __init xen_init_spinlocks(void)
{
- pv_lock_ops.lock_spinning = xen_lock_spinning;
+ pv_lock_ops.lock_spinning = PV_CALLEE_SAVE(xen_lock_spinning);
pv_lock_ops.unlock_kick = xen_unlock_kick;
}
--
1.7.2.3
next prev parent reply other threads:[~2010-11-16 21:09 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-11-16 21:08 [PATCH 00/14] PV ticket locks without expanding spinlock Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 01/14] x86/ticketlock: clean up types and accessors Jeremy Fitzhardinge
2011-01-11 17:21 ` [Xen-devel] " Konrad Rzeszutek Wilk
2010-11-16 21:08 ` [PATCH 02/14] x86/ticketlock: convert spin loop to C Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 03/14] x86/ticketlock: Use C for __ticket_spin_unlock Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 04/14] x86/ticketlock: make large and small ticket versions of spin_lock the same Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 05/14] x86/ticketlock: make __ticket_spin_lock common Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 06/14] x86/ticketlock: make __ticket_spin_trylock common Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 07/14] x86/spinlocks: replace pv spinlocks with pv ticketlocks Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 08/14] x86/ticketlock: collapse a layer of functions Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 09/14] xen/pvticketlock: Xen implementation for PV ticket locks Jeremy Fitzhardinge
2010-11-17 8:11 ` Jan Beulich
2010-11-17 8:52 ` Jeremy Fitzhardinge
2010-11-17 9:57 ` [Xen-devel] " Jeremy Fitzhardinge
2010-11-17 10:34 ` Jan Beulich
2010-11-17 17:41 ` Jeremy Fitzhardinge
2010-11-16 21:08 ` Jeremy Fitzhardinge [this message]
2010-11-16 21:08 ` [PATCH 11/14] x86/ticketlock: don't inline _spin_unlock when using paravirt spinlocks Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 12/14] x86/ticketlocks: when paravirtualizing ticket locks, increment by 2 Jeremy Fitzhardinge
2010-11-16 21:08 ` [PATCH 13/14] x86/ticketlock: add slowpath logic Jeremy Fitzhardinge
2010-11-17 8:31 ` Jan Beulich
2010-11-17 8:52 ` Jeremy Fitzhardinge
2010-11-17 8:56 ` Jeremy Fitzhardinge
2010-11-17 9:08 ` Jeremy Fitzhardinge
2010-11-17 9:34 ` Jan Beulich
2010-11-17 8:58 ` Avi Kivity
2010-11-17 9:05 ` Jeremy Fitzhardinge
2010-11-17 9:10 ` Avi Kivity
2010-11-17 12:21 ` Peter Zijlstra
2010-11-17 15:25 ` [Xen-devel] " Jeremy Fitzhardinge
2011-01-17 15:22 ` Srivatsa Vaddagiri
2011-01-19 16:23 ` Srivatsa Vaddagiri
2011-01-24 21:56 ` Jeremy Fitzhardinge
2011-02-18 17:03 ` Srivatsa Vaddagiri
2011-01-19 18:31 ` Jeremy Fitzhardinge
2011-01-19 18:39 ` Srivatsa Vaddagiri
2011-01-19 18:55 ` Jeremy Fitzhardinge
2011-01-20 4:28 ` Srivatsa Vaddagiri
2011-01-20 9:52 ` Jan Beulich
2010-11-16 21:08 ` [PATCH 14/14] x86/ticketlocks: tidy up __ticket_unlock_kick() Jeremy Fitzhardinge
2010-11-17 8:56 ` [PATCH 00/14] PV ticket locks without expanding spinlock Avi Kivity
2011-01-19 16:44 ` Srivatsa Vaddagiri
2011-01-19 17:07 ` [PATCH 1/3] debugfs: Add support to print u32 array Srivatsa Vaddagiri
2011-01-19 17:12 ` [PATCH 2/3] kvm hypervisor : Add hypercalls to support pv-ticketlock Srivatsa Vaddagiri
2011-01-19 17:21 ` Peter Zijlstra
2011-01-19 18:29 ` Srivatsa Vaddagiri
2011-01-19 18:53 ` Jeremy Fitzhardinge
2011-01-20 11:42 ` Srivatsa Vaddagiri
2011-01-20 17:49 ` Jeremy Fitzhardinge
2011-01-20 11:59 ` Srivatsa Vaddagiri
2011-01-20 13:41 ` Peter Zijlstra
2011-01-20 14:34 ` Srivatsa Vaddagiri
2011-01-20 17:56 ` Jeremy Fitzhardinge
2011-01-21 14:02 ` Srivatsa Vaddagiri
2011-01-21 14:48 ` Rik van Riel
2011-01-22 6:14 ` Srivatsa Vaddagiri
2011-01-22 14:53 ` Rik van Riel
2011-01-24 17:49 ` Jeremy Fitzhardinge
2011-01-19 17:23 ` Srivatsa Vaddagiri
2011-01-19 17:50 ` Peter Zijlstra
2011-01-19 17:17 ` [PATCH 3/3] kvm guest : Add support for pv-ticketlocks Srivatsa Vaddagiri
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=598aba88fd8411b063884264e1521e8e64b3cb15.1289940821.git.jeremy.fitzhardinge@citrix.com \
--to=jeremy@goop.org \
--cc=JBeulich@novell.com \
--cc=avi@redhat.com \
--cc=dada1@cosmosbay.com \
--cc=hpa@zytor.com \
--cc=jeremy.fitzhardinge@citrix.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mathieu.desnoyers@polymtl.ca \
--cc=npiggin@kernel.dk \
--cc=peterz@infradead.org \
--cc=vatsa@linux.vnet.ibm.com \
--cc=virtualization@lists.linux-foundation.org \
--cc=xen-devel@lists.xensource.com \
--cc=xiyou.wangcong@gmail.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).