All of lore.kernel.org
 help / color / mirror / Atom feed
From: Valentine Barshak <vbarshak@ru.mvista.com>
To: linuxppc-dev@ozlabs.org
Subject: [RFC][PATCH] PowerPC: 4xx PCIe indirect DCR spinlock fix.
Date: Tue, 5 Feb 2008 21:36:49 +0300	[thread overview]
Message-ID: <20080205183649.GA5136@ru.mvista.com> (raw)
In-Reply-To: <1202158239.7079.4.camel@pasglop>

Since we have mfdcri() and mtdcri() as macros, we can't use constructions, such
as "mtdcri(base, reg, mfdcri(base, reg) | val)". In this case the mfdcri() stuff
is not evaluated first. It's evaluated inside the mtdcri() macro and we have
the dcr_ind_lock spinlock acquired twice. To avoid this error, I've added
__mfdcri()/__mtdcri() inline functions that take the lock after register name
fix-up.

Signed-off-by: Valentine Barshak <vbarshak@ru.mvista.com>
---
 include/asm-powerpc/dcr-native.h |   49 +++++++++++++++++++++++----------------
 1 files changed, 30 insertions(+), 19 deletions(-)

diff -pruN linux-2.6.orig/include/asm-powerpc/dcr-native.h linux-2.6.bld/include/asm-powerpc/dcr-native.h
--- linux-2.6.orig/include/asm-powerpc/dcr-native.h	2008-02-05 16:44:54.000000000 +0300
+++ linux-2.6.bld/include/asm-powerpc/dcr-native.h	2008-02-05 19:11:55.000000000 +0300
@@ -59,25 +59,36 @@ do {								\
 /* R/W of indirect DCRs make use of standard naming conventions for DCRs */
 extern spinlock_t dcr_ind_lock;
 
-#define mfdcri(base, reg)				\
-({							\
-	unsigned long flags; 				\
-	unsigned int val;				\
-	spin_lock_irqsave(&dcr_ind_lock, flags);	\
-	mtdcr(DCRN_ ## base ## _CONFIG_ADDR, reg);	\
-	val = mfdcr(DCRN_ ## base ## _CONFIG_DATA);	\
-	spin_unlock_irqrestore(&dcr_ind_lock, flags);	\
-	val;						\
-})
-
-#define mtdcri(base, reg, data)				\
-do {							\
-	unsigned long flags; 				\
-	spin_lock_irqsave(&dcr_ind_lock, flags);	\
-	mtdcr(DCRN_ ## base ## _CONFIG_ADDR, reg);	\
-	mtdcr(DCRN_ ## base ## _CONFIG_DATA, data);	\
-	spin_unlock_irqrestore(&dcr_ind_lock, flags);	\
-} while (0)
+static inline unsigned __mfdcri(int base_addr, int base_data, int reg)
+{
+	unsigned long flags;
+	unsigned int val;
+
+	spin_lock_irqsave(&dcr_ind_lock, flags);
+	__mtdcr(base_addr, reg);
+	val = __mfdcr(base_data);
+	spin_unlock_irqrestore(&dcr_ind_lock, flags);
+	return val;
+}
+
+static inline void __mtdcri(int base_addr, int base_data, int reg,
+			    unsigned val)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&dcr_ind_lock, flags);
+	__mtdcr(base_addr, reg);
+	__mtdcr(base_data, val);
+	spin_unlock_irqrestore(&dcr_ind_lock, flags);
+}
+
+#define mfdcri(base, reg)	__mfdcri(DCRN_ ## base ## _CONFIG_ADDR,	\
+					 DCRN_ ## base ## _CONFIG_DATA,	\
+					 reg)
+
+#define mtdcri(base, reg, data)	__mtdcri(DCRN_ ## base ## _CONFIG_ADDR,	\
+					 DCRN_ ## base ## _CONFIG_DATA,	\
+					 reg, data)
 
 #endif /* __ASSEMBLY__ */
 #endif /* __KERNEL__ */

  reply	other threads:[~2008-02-05 18:38 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-02-04 18:27 [RFC][PATCH] PowerPC: 4xx PCIe indirect DCR spinlock fix Valentine Barshak
2008-02-04 20:50 ` Benjamin Herrenschmidt
2008-02-05 18:36   ` Valentine Barshak [this message]
2008-02-05 20:47     ` Benjamin Herrenschmidt

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=20080205183649.GA5136@ru.mvista.com \
    --to=vbarshak@ru.mvista.com \
    --cc=linuxppc-dev@ozlabs.org \
    /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.