Re: [KJ] remove SPIN_LOCK_UNLOCKED
On Tue, 10 Apr 2007, Matthew Wilcox wrote:
> On Tue, Apr 10, 2007 at 05:45:07PM -0400, Robert P. J. Day wrote:
> > that works fine if you're defining a single spinlock, but what do you
> > do in cases like this:
> >
> > arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] =
> > SPIN_LOCK_UNLOCKED
> >
> > that is, when you're assigning an array of them? you still need
> > some kind of generic, unnamed spinlock in those circumstances, no?
>
> That's a special case for architecture-only code. It's not to be
> used by drivers.
be that as it may, it still means you need to take it into account
whenever someone says they want to entirely remove the
SPIN_LOCK_UNLOCKED macro from the source tree, as suggested in
Documentation/spinlocks.txt.
if you do that removal, you can always replace SPIN_LOCK_UNLOCKED with
its current definition of __SPIN_LOCK_UNLOCKED(old_style_spin_init),
or what have you. but you would obviously have to replace it with
*something* that represents an unnamed spinlock if SPIN_LOCK_UNLOCKED
goes away.
rday
p.s. just FYI:
$ grep -r "\.\.\..*SPIN_LOCK_UNLOCKED" *
arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] =
SPIN_LOCK_UNLOCKED
arch/cris/arch-v32/kernel/smp.c:spinlock_t cris_atomic_locks[] = { [0 ...
LOCK_COUNT - 1] = SPIN_LOCK_UNLOCKED};
arch/parisc/lib/bitops.c: [0 ... (ATOMIC_HASH_SIZE-1)] =
__RAW_SPIN_LOCK_UNLOCKED
arch/mips/kernel/gdb-stub.c:[0 ... NR_CPUS-1] = __RAW_SPIN_LOCK_UNLOCKED,
arch/powerpc/platforms/iseries/htab.c: { [0 ... 63] = SPIN_LOCK_UNLOCKED};
so, as matthew says, it's clearly not for drivers.
--
Robert P. J. Day
Linux Consulting, Training and Annoying Kernel Pedantry
Waterloo, Ontario, CANADA
http://fsdev.net/wiki/index.php?title=Main_Page
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Re: [KJ] remove SPIN_LOCK_UNLOCKED
On 4/11/07, Matthew Wilcox <[EMAIL PROTECTED]> wrote:
On Tue, Apr 10, 2007 at 05:45:07PM -0400, Robert P. J. Day wrote:
> that works fine if you're defining a single spinlock, but what do you
> do in cases like this:
>
> arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] =
SPIN_LOCK_UNLOCKED
>
> that is, when you're assigning an array of them? you still need some
> kind of generic, unnamed spinlock in those circumstances, no?
That's a special case for architecture-only code. It's not to be used
by drivers.
as per my understanding, [which i should have keyed in earlier]
different places where SPIN_LOCK_UNLOCKED currently appears are
1. static spinlock_t foobar = SPIN_LOCK_UNLOCKED;
needs to be replaced bye DEFINE_SPINLOCK
e.g linux-core/drm_memory_debug.h
-static spinlock_t drm_mem_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(drm_mem_lock);
there are very few occurrences left in the tree i see
2. allocating a data structure dynamically
& initializing the spinlock embedded within
use spin_lock_init()
e.g linux-core/via_dmablit.c
- blitq->blit_lock = SPIN_LOCK_UNLOCKED;
+ spin_lock_init(>blit_lock);
3. static initialization of structure members
struct foo bar ={
.
.
.
.lock = SPIN_LOCK_UNLOCKED,
.
}
use
struct foo bar ={
.
.
.
.lock = __SPIN_LOCK_UNLOCKED(bar.lock),
.
}
e.g arch/i386/kernel/traps.c
- .lock = SPIN_LOCK_UNLOCKED,
+ .lock = __SPIN_LOCK_UNLOCKED(die.lock),
plenty of these are still there
may be some patches queued
4. arrays of spinlocks
e.g arch/cris/arch-v32/kernel/smp.c
-spinlock_t cris_atomic_locks[] = { [0 ... LOCK_COUNT - 1] =
SPIN_LOCK_UNLOCKED};
+raw_spinlock_t cris_atomic_locks[] = { [0 ... LOCK_COUNT - 1] =
__RAW_SPIN_LOCK_UNLOCKED};
my question is still there in the original post
about spin_lock_init()
CMIIW
Refer:
http://lkml.org/lkml/2005/6/20/47
http://lkml.org/lkml/2007/1/16/90
http://lists.openwall.net/linux-kernel/2007/02/01/258
--
Milind Arun Choudhary
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Re: [KJ] remove SPIN_LOCK_UNLOCKED
On Tue, Apr 10, 2007 at 05:45:07PM -0400, Robert P. J. Day wrote: > that works fine if you're defining a single spinlock, but what do you > do in cases like this: > > arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] = > SPIN_LOCK_UNLOCKED > > that is, when you're assigning an array of them? you still need some > kind of generic, unnamed spinlock in those circumstances, no? That's a special case for architecture-only code. It's not to be used by drivers. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
> > Don't worry about the __RAW_SPIN_LOCK_UNLOCKED stuff, that's > > obviously not for generic code to use. The right answer (as I said > > before) is to use DEFINE_SPINLOCK(). > > that works fine if you're defining a single spinlock, but what do you > do in cases like this: > > arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] = > SPIN_LOCK_UNLOCKED > > that is, when you're assigning an array of them? you still need some > kind of generic, unnamed spinlock in those circumstances, no? Wow, I didn't realize there was code doing that. I guess for that handful of cases, you indeed would probably want to convert them to raw_spinlock_t and use __RAW_SPIN_LOCK_UNLOCKED. But in the vast majority of cases, DEFINE_SPINLOCK() is the right think to do. - R. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
On Tue, 10 Apr 2007, Roland Dreier wrote: > > >but that's where you would use the more explicit > > >__RAW_SPIN_LOCK_UNLOCKED, no? AFAIK, you really can remove the macro > > >SPIN_LOCK_UNLOCKED in its entirety. > > > > I don't remember LDD speaking about __RAW_*. (And other than not > > having looked into the code to date, I don't know the difference.) > > Don't worry about the __RAW_SPIN_LOCK_UNLOCKED stuff, that's > obviously not for generic code to use. The right answer (as I said > before) is to use DEFINE_SPINLOCK(). that works fine if you're defining a single spinlock, but what do you do in cases like this: arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED that is, when you're assigning an array of them? you still need some kind of generic, unnamed spinlock in those circumstances, no? rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://fsdev.net/wiki/index.php?title=Main_Page - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
> >but that's where you would use the more explicit > >__RAW_SPIN_LOCK_UNLOCKED, no? AFAIK, you really can remove the macro > >SPIN_LOCK_UNLOCKED in its entirety. > > I don't remember LDD speaking about __RAW_*. (And other than not > having looked into the code to date, I don't know the difference.) Don't worry about the __RAW_SPIN_LOCK_UNLOCKED stuff, that's obviously not for generic code to use. The right answer (as I said before) is to use DEFINE_SPINLOCK(). - R. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
On Apr 10 2007 17:25, Robert P. J. Day wrote: >On Tue, 10 Apr 2007, Jan Engelhardt wrote: >> On Apr 10 2007 23:46, Milind Arun Choudhary wrote: >> >> >"use spin_lock_init instead of SPIN_LOCK_UNLOCKED" >> >> Fact is, we cannot remove SPIN_LOCK_UNLOCKED. It's needed for >> variables outside functions: >> >> static spinlock_t foobar = SPIN_LOCK_UNLOCKED; > >but that's where you would use the more explicit >__RAW_SPIN_LOCK_UNLOCKED, no? AFAIK, you really can remove the macro >SPIN_LOCK_UNLOCKED in its entirety. I don't remember LDD speaking about __RAW_*. (And other than not having looked into the code to date, I don't know the difference.) Jan -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
On Tue, 10 Apr 2007, Jan Engelhardt wrote: > > On Apr 10 2007 23:46, Milind Arun Choudhary wrote: > > >"use spin_lock_init instead of SPIN_LOCK_UNLOCKED" > > Fact is, we cannot remove SPIN_LOCK_UNLOCKED. It's needed for > variables outside functions: > > static spinlock_t foobar = SPIN_LOCK_UNLOCKED; but that's where you would use the more explicit __RAW_SPIN_LOCK_UNLOCKED, no? AFAIK, you really can remove the macro SPIN_LOCK_UNLOCKED in its entirety. rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://fsdev.net/wiki/index.php?title=Main_Page - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
> Fact is, we cannot remove SPIN_LOCK_UNLOCKED. It's needed for > variables outside functions: > > static spinlock_t foobar = SPIN_LOCK_UNLOCKED; DEFINE_SPINLOCK() is provided to define variables that way. - R. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
On Apr 10 2007 23:46, Milind Arun Choudhary wrote: >"use spin_lock_init instead of SPIN_LOCK_UNLOCKED" Fact is, we cannot remove SPIN_LOCK_UNLOCKED. It's needed for variables outside functions: static spinlock_t foobar = SPIN_LOCK_UNLOCKED; >let me know if this is fine .. not for me to comment :) > aerdrv.c |2 +- > 1 files changed, 1 insertion(+), 1 deletion(-) > >diff --git a/drivers/pci/pcie/aer/aerdrv.c b/drivers/pci/pcie/aer/aerdrv.c >index db6ad8e..6846fb4 100644 >--- a/drivers/pci/pcie/aer/aerdrv.c >+++ b/drivers/pci/pcie/aer/aerdrv.c >@@ -157,7 +157,7 @@ static struct aer_rpc* aer_alloc_rpc(struct pcie_device >*dev) >* Initialize Root lock access, e_lock, to Root Error Status Reg, >* Root Error ID Reg, and Root error producer/consumer index. >*/ >- rpc->e_lock = SPIN_LOCK_UNLOCKED; >+ spin_lock_init(>e_lock); > > rpc->rpd = dev; > INIT_WORK(>dpc_handler, aer_isr); > > >-- >Milind Arun Choudhary >- >To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >the body of a message to [EMAIL PROTECTED] >More majordomo info at http://vger.kernel.org/majordomo-info.html >Please read the FAQ at http://www.tux.org/lkml/ > Jan -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
On Apr 10 2007 23:46, Milind Arun Choudhary wrote: use spin_lock_init instead of SPIN_LOCK_UNLOCKED Fact is, we cannot remove SPIN_LOCK_UNLOCKED. It's needed for variables outside functions: static spinlock_t foobar = SPIN_LOCK_UNLOCKED; let me know if this is fine .. not for me to comment :) aerdrv.c |2 +- 1 files changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/pcie/aer/aerdrv.c b/drivers/pci/pcie/aer/aerdrv.c index db6ad8e..6846fb4 100644 --- a/drivers/pci/pcie/aer/aerdrv.c +++ b/drivers/pci/pcie/aer/aerdrv.c @@ -157,7 +157,7 @@ static struct aer_rpc* aer_alloc_rpc(struct pcie_device *dev) * Initialize Root lock access, e_lock, to Root Error Status Reg, * Root Error ID Reg, and Root error producer/consumer index. */ - rpc-e_lock = SPIN_LOCK_UNLOCKED; + spin_lock_init(rpc-e_lock); rpc-rpd = dev; INIT_WORK(rpc-dpc_handler, aer_isr); -- Milind Arun Choudhary - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ Jan -- - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
Fact is, we cannot remove SPIN_LOCK_UNLOCKED. It's needed for variables outside functions: static spinlock_t foobar = SPIN_LOCK_UNLOCKED; DEFINE_SPINLOCK() is provided to define variables that way. - R. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
On Tue, 10 Apr 2007, Jan Engelhardt wrote: On Apr 10 2007 23:46, Milind Arun Choudhary wrote: use spin_lock_init instead of SPIN_LOCK_UNLOCKED Fact is, we cannot remove SPIN_LOCK_UNLOCKED. It's needed for variables outside functions: static spinlock_t foobar = SPIN_LOCK_UNLOCKED; but that's where you would use the more explicit __RAW_SPIN_LOCK_UNLOCKED, no? AFAIK, you really can remove the macro SPIN_LOCK_UNLOCKED in its entirety. rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://fsdev.net/wiki/index.php?title=Main_Page - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
On Apr 10 2007 17:25, Robert P. J. Day wrote: On Tue, 10 Apr 2007, Jan Engelhardt wrote: On Apr 10 2007 23:46, Milind Arun Choudhary wrote: use spin_lock_init instead of SPIN_LOCK_UNLOCKED Fact is, we cannot remove SPIN_LOCK_UNLOCKED. It's needed for variables outside functions: static spinlock_t foobar = SPIN_LOCK_UNLOCKED; but that's where you would use the more explicit __RAW_SPIN_LOCK_UNLOCKED, no? AFAIK, you really can remove the macro SPIN_LOCK_UNLOCKED in its entirety. I don't remember LDD speaking about __RAW_*. (And other than not having looked into the code to date, I don't know the difference.) Jan -- - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
but that's where you would use the more explicit __RAW_SPIN_LOCK_UNLOCKED, no? AFAIK, you really can remove the macro SPIN_LOCK_UNLOCKED in its entirety. I don't remember LDD speaking about __RAW_*. (And other than not having looked into the code to date, I don't know the difference.) Don't worry about the __RAW_SPIN_LOCK_UNLOCKED stuff, that's obviously not for generic code to use. The right answer (as I said before) is to use DEFINE_SPINLOCK(). - R. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
On Tue, 10 Apr 2007, Roland Dreier wrote: but that's where you would use the more explicit __RAW_SPIN_LOCK_UNLOCKED, no? AFAIK, you really can remove the macro SPIN_LOCK_UNLOCKED in its entirety. I don't remember LDD speaking about __RAW_*. (And other than not having looked into the code to date, I don't know the difference.) Don't worry about the __RAW_SPIN_LOCK_UNLOCKED stuff, that's obviously not for generic code to use. The right answer (as I said before) is to use DEFINE_SPINLOCK(). that works fine if you're defining a single spinlock, but what do you do in cases like this: arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED that is, when you're assigning an array of them? you still need some kind of generic, unnamed spinlock in those circumstances, no? rday -- Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry Waterloo, Ontario, CANADA http://fsdev.net/wiki/index.php?title=Main_Page - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ]remove SPIN_LOCK_UNLOCKED
Don't worry about the __RAW_SPIN_LOCK_UNLOCKED stuff, that's obviously not for generic code to use. The right answer (as I said before) is to use DEFINE_SPINLOCK(). that works fine if you're defining a single spinlock, but what do you do in cases like this: arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED that is, when you're assigning an array of them? you still need some kind of generic, unnamed spinlock in those circumstances, no? Wow, I didn't realize there was code doing that. I guess for that handful of cases, you indeed would probably want to convert them to raw_spinlock_t and use __RAW_SPIN_LOCK_UNLOCKED. But in the vast majority of cases, DEFINE_SPINLOCK() is the right think to do. - R. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ] remove SPIN_LOCK_UNLOCKED
On Tue, Apr 10, 2007 at 05:45:07PM -0400, Robert P. J. Day wrote: that works fine if you're defining a single spinlock, but what do you do in cases like this: arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] = SPIN_LOCK_UNLOCKED that is, when you're assigning an array of them? you still need some kind of generic, unnamed spinlock in those circumstances, no? That's a special case for architecture-only code. It's not to be used by drivers. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ] remove SPIN_LOCK_UNLOCKED
On 4/11/07, Matthew Wilcox [EMAIL PROTECTED] wrote:
On Tue, Apr 10, 2007 at 05:45:07PM -0400, Robert P. J. Day wrote:
that works fine if you're defining a single spinlock, but what do you
do in cases like this:
arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] =
SPIN_LOCK_UNLOCKED
that is, when you're assigning an array of them? you still need some
kind of generic, unnamed spinlock in those circumstances, no?
That's a special case for architecture-only code. It's not to be used
by drivers.
as per my understanding, [which i should have keyed in earlier]
different places where SPIN_LOCK_UNLOCKED currently appears are
1. static spinlock_t foobar = SPIN_LOCK_UNLOCKED;
needs to be replaced bye DEFINE_SPINLOCK
e.g linux-core/drm_memory_debug.h
-static spinlock_t drm_mem_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(drm_mem_lock);
there are very few occurrences left in the tree i see
2. allocating a data structure dynamically
initializing the spinlock embedded within
use spin_lock_init()
e.g linux-core/via_dmablit.c
- blitq-blit_lock = SPIN_LOCK_UNLOCKED;
+ spin_lock_init(blitq-blit_lock);
3. static initialization of structure members
struct foo bar ={
.
.
.
.lock = SPIN_LOCK_UNLOCKED,
.
}
use
struct foo bar ={
.
.
.
.lock = __SPIN_LOCK_UNLOCKED(bar.lock),
.
}
e.g arch/i386/kernel/traps.c
- .lock = SPIN_LOCK_UNLOCKED,
+ .lock = __SPIN_LOCK_UNLOCKED(die.lock),
plenty of these are still there
may be some patches queued
4. arrays of spinlocks
e.g arch/cris/arch-v32/kernel/smp.c
-spinlock_t cris_atomic_locks[] = { [0 ... LOCK_COUNT - 1] =
SPIN_LOCK_UNLOCKED};
+raw_spinlock_t cris_atomic_locks[] = { [0 ... LOCK_COUNT - 1] =
__RAW_SPIN_LOCK_UNLOCKED};
my question is still there in the original post
about spin_lock_init()
CMIIW
Refer:
http://lkml.org/lkml/2005/6/20/47
http://lkml.org/lkml/2007/1/16/90
http://lists.openwall.net/linux-kernel/2007/02/01/258
--
Milind Arun Choudhary
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
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Please read the FAQ at http://www.tux.org/lkml/
Re: [KJ] remove SPIN_LOCK_UNLOCKED
On Tue, 10 Apr 2007, Matthew Wilcox wrote:
On Tue, Apr 10, 2007 at 05:45:07PM -0400, Robert P. J. Day wrote:
that works fine if you're defining a single spinlock, but what do you
do in cases like this:
arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] =
SPIN_LOCK_UNLOCKED
that is, when you're assigning an array of them? you still need
some kind of generic, unnamed spinlock in those circumstances, no?
That's a special case for architecture-only code. It's not to be
used by drivers.
be that as it may, it still means you need to take it into account
whenever someone says they want to entirely remove the
SPIN_LOCK_UNLOCKED macro from the source tree, as suggested in
Documentation/spinlocks.txt.
if you do that removal, you can always replace SPIN_LOCK_UNLOCKED with
its current definition of __SPIN_LOCK_UNLOCKED(old_style_spin_init),
or what have you. but you would obviously have to replace it with
*something* that represents an unnamed spinlock if SPIN_LOCK_UNLOCKED
goes away.
rday
p.s. just FYI:
$ grep -r \.\.\..*SPIN_LOCK_UNLOCKED *
arch/sparc/lib/atomic32.c: [0 ... (ATOMIC_HASH_SIZE-1)] =
SPIN_LOCK_UNLOCKED
arch/cris/arch-v32/kernel/smp.c:spinlock_t cris_atomic_locks[] = { [0 ...
LOCK_COUNT - 1] = SPIN_LOCK_UNLOCKED};
arch/parisc/lib/bitops.c: [0 ... (ATOMIC_HASH_SIZE-1)] =
__RAW_SPIN_LOCK_UNLOCKED
arch/mips/kernel/gdb-stub.c:[0 ... NR_CPUS-1] = __RAW_SPIN_LOCK_UNLOCKED,
arch/powerpc/platforms/iseries/htab.c: { [0 ... 63] = SPIN_LOCK_UNLOCKED};
so, as matthew says, it's clearly not for drivers.
--
Robert P. J. Day
Linux Consulting, Training and Annoying Kernel Pedantry
Waterloo, Ontario, CANADA
http://fsdev.net/wiki/index.php?title=Main_Page
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
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