Subject: [merged] lglock-map-to-spinlock-when-config_smp.patch removed from -mm tree To: josh@xxxxxxxxxxxxxxxx,a.p.zijlstra@xxxxxxxxx,dhowells@xxxxxxxxxx,hpa@xxxxxxxxx,mmarek@xxxxxxx,npiggin@xxxxxxxxx,rusty@xxxxxxxxxxxxxxx,tglx@xxxxxxxxxxxxx,mm-commits@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Tue, 08 Apr 2014 14:49:21 -0700 The patch titled Subject: lglock: map to spinlock when !CONFIG_SMP has been removed from the -mm tree. Its filename was lglock-map-to-spinlock-when-config_smp.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Josh Triplett <josh@xxxxxxxxxxxxxxxx> Subject: lglock: map to spinlock when !CONFIG_SMP When the system has only one CPU, lglock is effectively a spinlock; map it directly to spinlock to eliminate the indirection and duplicate code. In addition to removing overhead, this drops 1.6k of code with a defconfig modified to have !CONFIG_SMP, and 1.1k with a minimal config. Signed-off-by: Josh Triplett <josh@xxxxxxxxxxxxxxxx> Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx> Cc: Michal Marek <mmarek@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: David Howells <dhowells@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Nick Piggin <npiggin@xxxxxxxxx> Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/lglock.h | 16 ++++++++++++++++ kernel/locking/Makefile | 3 ++- 2 files changed, 18 insertions(+), 1 deletion(-) diff -puN include/linux/lglock.h~lglock-map-to-spinlock-when-config_smp include/linux/lglock.h --- a/include/linux/lglock.h~lglock-map-to-spinlock-when-config_smp +++ a/include/linux/lglock.h @@ -25,6 +25,8 @@ #include <linux/cpu.h> #include <linux/notifier.h> +#ifdef CONFIG_SMP + #ifdef CONFIG_DEBUG_LOCK_ALLOC #define LOCKDEP_INIT_MAP lockdep_init_map #else @@ -57,4 +59,18 @@ void lg_local_unlock_cpu(struct lglock * void lg_global_lock(struct lglock *lg); void lg_global_unlock(struct lglock *lg); +#else +/* When !CONFIG_SMP, map lglock to spinlock */ +#define lglock spinlock +#define DEFINE_LGLOCK(name) DEFINE_SPINLOCK(name) +#define DEFINE_STATIC_LGLOCK(name) static DEFINE_SPINLOCK(name) +#define lg_lock_init(lg, name) spin_lock_init(lg) +#define lg_local_lock spin_lock +#define lg_local_unlock spin_unlock +#define lg_local_lock_cpu(lg, cpu) spin_lock(lg) +#define lg_local_unlock_cpu(lg, cpu) spin_unlock(lg) +#define lg_global_lock spin_lock +#define lg_global_unlock spin_unlock +#endif + #endif diff -puN kernel/locking/Makefile~lglock-map-to-spinlock-when-config_smp kernel/locking/Makefile --- a/kernel/locking/Makefile~lglock-map-to-spinlock-when-config_smp +++ a/kernel/locking/Makefile @@ -1,5 +1,5 @@ -obj-y += mutex.o semaphore.o rwsem.o lglock.o mcs_spinlock.o +obj-y += mutex.o semaphore.o rwsem.o mcs_spinlock.o ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_lockdep.o = -pg @@ -14,6 +14,7 @@ ifeq ($(CONFIG_PROC_FS),y) obj-$(CONFIG_LOCKDEP) += lockdep_proc.o endif obj-$(CONFIG_SMP) += spinlock.o +obj-$(CONFIG_SMP) += lglock.o obj-$(CONFIG_PROVE_LOCKING) += spinlock.o obj-$(CONFIG_RT_MUTEXES) += rtmutex.o obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o _ Patches currently in -mm which might be from josh@xxxxxxxxxxxxxxxx are origin.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html