[PATCH 0/10] fix usages of local_irq_save() and local_irq_disable()

[PATCH 0/10] fix usages of local_irq_save() and local_irq_disable()

[Jiri Kosina]

Hi,

the following series of 10 trivial patches contains two changes:

- removes local_irq_disable() on redundant places after local_irq_save()
- turns local_save_flags() + local_irq_disable() into local_irq_save()

It was quite surprising to find it on so many places. There is another gem 
in drivers/block/ataflop.c::do_fd_request():

        local_save_flags(flags);        /* The request function is called with ints
        local_irq_disable();             * disabled... so must save the IPL for later */

I am not sure if the author was aware of the fact that he commented also 
the local_irq_disable() call :) I will look into the code a bit more 
later, to see whether it just really wants to save flags, or this should 
be converted into standard local_irq_save(flags).

-- 
Jiri Kosina

[PATCH 1/10] CRIS: local_irq_disable() is redundant after local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

CRIS: local_irq_disable() is redundant after local_irq_save()

arch/cris/arch-v10/kernel/time.c::get_ns_in_jiffie() contains
local_irq_disable() call after local_irq_save(). This looks
redundant.

arch/cris/kernel/time.c::do_gettimeofday() contains
local_irq_disable() call after local_irq_save(). This looks
redundant.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 arch/cris/arch-v10/kernel/time.c |    1 -
 arch/cris/kernel/time.c          |    1 -
 2 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/arch/cris/arch-v10/kernel/time.c b/arch/cris/arch-v10/kernel/time.c
index ebacf14..077e973 100644
--- a/arch/cris/arch-v10/kernel/time.c
+++ b/arch/cris/arch-v10/kernel/time.c
@@ -38,7 +38,6 @@ unsigned long get_ns_in_jiffie(void)
 	unsigned long flags;
 
 	local_irq_save(flags);
-	local_irq_disable();
 	timer_count = *R_TIMER0_DATA;
 	presc_count = *R_TIM_PRESC_STATUS;  
 	/* presc_count might be wrapped */
diff --git a/arch/cris/kernel/time.c b/arch/cris/kernel/time.c
index 0f9213c..22a1aa5 100644
--- a/arch/cris/kernel/time.c
+++ b/arch/cris/kernel/time.c
@@ -55,7 +55,6 @@ void do_gettimeofday(struct timeval *tv)
 	unsigned long flags;
 	signed long usec, sec;
 	local_irq_save(flags);
-	local_irq_disable();
 	usec = do_gettimeoffset();
 
         /*

[PATCH 2/10] X86_64: local_irq_disable() is redundant after local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

X86_64: local_irq_disable() is redundant after local_irq_save()

arch/x86_64/kernel/time.c::hpet_calibrate_tsc() contains
local_irq_disable() call after local_irq_save(). This looks
redundant.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 arch/x86_64/kernel/time.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index 5cc76d0..1a8afdc 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -683,7 +683,6 @@ static unsigned int __init hpet_calibrate_tsc(void)
 	unsigned long flags;
 
 	local_irq_save(flags);
-	local_irq_disable();
 
 	read_hpet_tsc(&hpet_start, &tsc_start);
 

[PATCH 3/10] POWERPC-86xx: local_irq_disable() is redundant after local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

POWERPC-86xx: local_irq_disable() is redundant after local_irq_save()

arch/powerpc/platforms/86xx/mpc86xx_smp.c::smp_86xx_kick_cpu() contains
local_irq_disable() call after local_irq_save(). This looks
redundant.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 arch/powerpc/platforms/86xx/mpc86xx_smp.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/platforms/86xx/mpc86xx_smp.c b/arch/powerpc/platforms/86xx/mpc86xx_smp.c
index bb7fb41..7ef0c68 100644
--- a/arch/powerpc/platforms/86xx/mpc86xx_smp.c
+++ b/arch/powerpc/platforms/86xx/mpc86xx_smp.c
@@ -65,7 +65,6 @@ smp_86xx_kick_cpu(int nr)
 	pr_debug("smp_86xx_kick_cpu: kick CPU #%d\n", nr);
 
 	local_irq_save(flags);
-	local_irq_disable();
 
 	/* Save reset vector */
 	save_vector = *vector;

[PATCH 4/10] POWERPC-Powermac: local_irq_disable() is redundant after local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

POWERPC-Powermac: local_irq_disable() is redundant after local_irq_save()

arch/powerpc/platforms/powermac/smp.c::smp_core99_kick_cpu() contains
local_irq_disable() call after local_irq_save(). This looks
redundant.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 arch/powerpc/platforms/powermac/smp.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/platforms/powermac/smp.c b/arch/powerpc/platforms/powermac/smp.c
index eeb2ae5..d73fb73 100644
--- a/arch/powerpc/platforms/powermac/smp.c
+++ b/arch/powerpc/platforms/powermac/smp.c
@@ -795,7 +795,6 @@ static void __devinit smp_core99_kick_cpu(int nr)
 		ppc_md.progress("smp_core99_kick_cpu", 0x346);
 
 	local_irq_save(flags);
-	local_irq_disable();
 
 	/* Save reset vector */
 	save_vector = *vector;

[PATCH 5/10] SCSI-BusLogic: local_irq_disable() is redundant after local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

SCSI-BusLogic: local_irq_disable() is redundant after local_irq_save()

drivers/scsi/BusLogic.c::BusLogic_Command() contains
local_irq_disable() call after local_irq_save(). This looks
redundant.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 drivers/scsi/BusLogic.c |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/BusLogic.c b/drivers/scsi/BusLogic.c
index 3075204..6272ec2 100644
--- a/drivers/scsi/BusLogic.c
+++ b/drivers/scsi/BusLogic.c
@@ -362,10 +362,8 @@ static int BusLogic_Command(struct BusLogic_HostAdapter *HostAdapter, enum BusLo
 	   interrupt could occur if the IRQ Channel was previously enabled by another
 	   BusLogic Host Adapter or another driver sharing the same IRQ Channel.
 	 */
-	if (!HostAdapter->IRQ_ChannelAcquired) {
+	if (!HostAdapter->IRQ_ChannelAcquired)
 		local_irq_save(ProcessorFlags);
-		local_irq_disable();
-	}
 	/*
 	   Wait for the Host Adapter Ready bit to be set and the Command/Parameter
 	   Register Busy bit to be reset in the Status Register.

[PATCH 6/10] CHAR-Amiserial: turn local_save_flags() + local_irq_disable() into local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

CHAR-Amiserial: turn local_save_flags() + local_irq_disable() into local_irq_save()

drivers/char/amiserial.c::rs_write() contains local_irq_disable()
after local_save_flags(). Turn it into local_irq_save().

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 drivers/char/amiserial.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/char/amiserial.c b/drivers/char/amiserial.c
index feb4ac8..61f646b 100644
--- a/drivers/char/amiserial.c
+++ b/drivers/char/amiserial.c
@@ -904,8 +904,7 @@ static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count
 	if (!info->xmit.buf)
 		return 0;
 
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	while (1) {
 		c = CIRC_SPACE_TO_END(info->xmit.head,
 				      info->xmit.tail,

[PATCH 7/10] CHAR-Amiserial: turn local_save_flags() + local_irq_disable() into local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

CHAR-Amiserial: turn local_save_flags() + local_irq_disable() into local_irq_save()

drivers/char/amiserial.c::rs_write() contains local_irq_disable()
after local_save_flags(). Turn it into local_irq_save().

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 drivers/char/amiserial.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/char/amiserial.c b/drivers/char/amiserial.c
index feb4ac8..61f646b 100644
--- a/drivers/char/amiserial.c
+++ b/drivers/char/amiserial.c
@@ -904,8 +904,7 @@ static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count
 	if (!info->xmit.buf)
 		return 0;
 
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	while (1) {
 		c = CIRC_SPACE_TO_END(info->xmit.head,
 				      info->xmit.tail,

[PATCH 8/10] NET-3c59x: turn local_save_flags() + local_irq_disable() into local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

NET-3c59x: turn local_save_flags() + local_irq_disable() into local_irq_save()

drivers/net/3c59x.c::poll_vortex() contains local_irq_disable()
after local_save_flags(). Turn it into local_irq_save().

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 drivers/net/3c59x.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/drivers/net/3c59x.c b/drivers/net/3c59x.c
index 80bdcf8..716a472 100644
--- a/drivers/net/3c59x.c
+++ b/drivers/net/3c59x.c
@@ -792,8 +792,7 @@ static void poll_vortex(struct net_device *dev)
 {
 	struct vortex_private *vp = netdev_priv(dev);
 	unsigned long flags;
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	(vp->full_bus_master_rx ? boomerang_interrupt:vortex_interrupt)(dev->irq,dev);
 	local_irq_restore(flags);
 }

[PATCH 9/10] CRIS: turn local_save_flags() + local_irq_disable() into local_irq_save() in headers

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

CRIS: turn local_save_flags() + local_irq_disable() into local_irq_save() in headers

Various headers for CRIS architecture contain local_irq_disable()
after local_save_flags(). Turn it into local_irq_save().

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 drivers/net/amd8111e.c              |    3 +--
 include/asm-cris/semaphore-helper.h |    9 +++------
 include/asm-cris/system.h           |    3 +--
 3 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/net/amd8111e.c b/drivers/net/amd8111e.c
index 18896f2..9c399aa 100644
--- a/drivers/net/amd8111e.c
+++ b/drivers/net/amd8111e.c
@@ -1334,8 +1334,7 @@ err_no_interrupt:
 static void amd8111e_poll(struct net_device *dev)
 {
 	unsigned long flags;
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	amd8111e_interrupt(0, dev);
 	local_irq_restore(flags);
 }
diff --git a/include/asm-cris/semaphore-helper.h b/include/asm-cris/semaphore-helper.h
index a8e1e6c..27bfeca 100644
--- a/include/asm-cris/semaphore-helper.h
+++ b/include/asm-cris/semaphore-helper.h
@@ -30,8 +30,7 @@ static inline int waking_non_zero(struct semaphore *sem)
 	unsigned long flags;
 	int ret = 0;
 
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	if (read(&sem->waking) > 0) {
 		dec(&sem->waking);
 		ret = 1;
@@ -46,8 +45,7 @@ static inline int waking_non_zero_interruptible(struct semaphore *sem,
 	int ret = 0;
 	unsigned long flags;
 
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	if (read(&sem->waking) > 0) {
 		dec(&sem->waking);
 		ret = 1;
@@ -64,8 +62,7 @@ static inline int waking_non_zero_trylock(struct semaphore *sem)
         int ret = 1;
 	unsigned long flags;
 
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	if (read(&sem->waking) <= 0)
 		inc(&sem->count);
 	else {
diff --git a/include/asm-cris/system.h b/include/asm-cris/system.h
index b869f61..fea0e8d 100644
--- a/include/asm-cris/system.h
+++ b/include/asm-cris/system.h
@@ -44,8 +44,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz
   /* since Etrax doesn't have any atomic xchg instructions, we need to disable
      irq's (if enabled) and do it with move.d's */
   unsigned long flags,temp;
-  local_save_flags(flags); /* save flags, including irq enable bit */
-  local_irq_disable();             /* shut off irq's */
+  local_irq_save(flags); /* save flags, including irq enable bit and shut off irqs */
   switch (size) {
   case 1:
     *((unsigned char *)&temp) = x;

[PATCH 10/10] CRIS: turn local_save_flags() + local_irq_disable() into local_irq_save()

[Jiri Kosina]

From: Jiri Kosina <jkosina@suse.cz>

CRIS: turn local_save_flags() + local_irq_disable() into local_irq_save()

TLB handling for CRIS contains local_irq_disable() after local_save_flags().
Turn this into local_irq_save().

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

---

 arch/cris/arch-v10/mm/tlb.c |    9 +++------
 arch/cris/arch-v32/mm/tlb.c |    9 +++------
 2 files changed, 6 insertions(+), 12 deletions(-)

diff --git a/arch/cris/arch-v10/mm/tlb.c b/arch/cris/arch-v10/mm/tlb.c
index 70a5523..7d9fec8 100644
--- a/arch/cris/arch-v10/mm/tlb.c
+++ b/arch/cris/arch-v10/mm/tlb.c
@@ -42,8 +42,7 @@ flush_tlb_all(void)
 	 * in the same 4-way entry group. details.. 
 	 */
 
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	for(i = 0; i < NUM_TLB_ENTRIES; i++) {
 		*R_TLB_SELECT = ( IO_FIELD(R_TLB_SELECT, index, i) );
 		*R_TLB_HI = ( IO_FIELD(R_TLB_HI, page_id, INVALID_PAGEID ) |
@@ -78,8 +77,7 @@ flush_tlb_mm(struct mm_struct *mm)
 	 * global pages. is it worth the extra I/O ? 
 	 */
 
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	for(i = 0; i < NUM_TLB_ENTRIES; i++) {
 		*R_TLB_SELECT = IO_FIELD(R_TLB_SELECT, index, i);
 		if (IO_EXTRACT(R_TLB_HI, page_id, *R_TLB_HI) == page_id) {
@@ -118,8 +116,7 @@ flush_tlb_page(struct vm_area_struct *vma,
 	 * and the virtual address requested 
 	 */
 
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 	for(i = 0; i < NUM_TLB_ENTRIES; i++) {
 		unsigned long tlb_hi;
 		*R_TLB_SELECT = IO_FIELD(R_TLB_SELECT, index, i);
diff --git a/arch/cris/arch-v32/mm/tlb.c b/arch/cris/arch-v32/mm/tlb.c
index 9d75d76..c2d12e9 100644
--- a/arch/cris/arch-v32/mm/tlb.c
+++ b/arch/cris/arch-v32/mm/tlb.c
@@ -54,8 +54,7 @@ __flush_tlb_all(void)
 	 * Mask with 0xf so similar TLB entries aren't written in the same 4-way
 	 * entry group.
 	 */
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 
 	for (mmu = 1; mmu <= 2; mmu++) {
 		SUPP_BANK_SEL(mmu); /* Select the MMU */
@@ -92,8 +91,7 @@ __flush_tlb_mm(struct mm_struct *mm)
 		return;
 
 	/* Mark the TLB entries that match the page_id as invalid. */
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 
 	for (mmu = 1; mmu <= 2; mmu++) {
 		SUPP_BANK_SEL(mmu);
@@ -140,8 +138,7 @@ __flush_tlb_page(struct vm_area_struct *vma, unsigned long addr)
 	 * Invalidate those TLB entries that match both the mm context and the
 	 * requested virtual address.
 	 */
-	local_save_flags(flags);
-	local_irq_disable();
+	local_irq_save(flags);
 
 	for (mmu = 1; mmu <= 2; mmu++) {
 		SUPP_BANK_SEL(mmu);