Commit 531258aa authored by Mike Gerdts's avatar Mike Gerdts Committed by Jim Harris
Browse files

thread: get debug stack traces on spinlocks 



To help debug spinlocks, capture stack traces as spinlocks are used.
Future commits in this series will make debugging with these stack
traces easier.

Signed-off-by: default avatarMike Gerdts <mgerdts@nvidia.com>
Change-Id: I597b730ca771ea3c5b831f5ba4058d359215f7f6
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/15998


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <smatsumoto@nvidia.com>
parent 268078c1

include/spdk/thread.h

+1 −0
Original line number Diff line number Diff line
@@ -904,6 +904,7 @@ bool spdk_interrupt_mode_is_enabled(void); 
struct spdk_spinlock {

	pthread_spinlock_t spinlock;

	struct spdk_thread *thread;

	struct spdk_spinlock_internal *internal;

};



/**

lib/thread/thread.c

+55 −0
Original line number Diff line number Diff line
@@ -25,6 +25,11 @@ 
#ifdef __linux__

#include <sys/timerfd.h>

#include <sys/eventfd.h>

#include <execinfo.h>

#endif



#ifdef __FreeBSD__

#include <execinfo.h>

#endif



#define SPDK_MSG_BATCH_SIZE		8
@@ -2876,6 +2881,48 @@ spdk_interrupt_mode_is_enabled(void) 
	return g_interrupt_mode;

}



#define SSPIN_DEBUG_STACK_FRAMES 16



struct sspin_stack {

	void *addrs[SSPIN_DEBUG_STACK_FRAMES];

	uint32_t depth;

};



struct spdk_spinlock_internal {

	struct sspin_stack init_stack;

	struct sspin_stack lock_stack;

	struct sspin_stack unlock_stack;

};



static void

sspin_init_internal(struct spdk_spinlock *sspin)

{

#ifdef DEBUG

	sspin->internal = calloc(1, sizeof(*sspin->internal));

#endif

}



static void

sspin_fini_internal(struct spdk_spinlock *sspin)

{

#ifdef DEBUG

	free(sspin->internal);

	sspin->internal = NULL;

#endif

}



#ifdef DEBUG

#define SSPIN_GET_STACK(sspin, which) \

	do { \

		if (sspin->internal != NULL) { \

			struct sspin_stack *stack = &sspin->internal->which ## _stack; \

			stack->depth = backtrace(stack->addrs, SPDK_COUNTOF(stack->addrs)); \

		} \

	} while (0)

#else

#define SSPIN_GET_STACK(sspin, which) do { } while (0)

#endif



void

spdk_spin_init(struct spdk_spinlock *sspin)

{
@@ -2884,6 +2931,8 @@ spdk_spin_init(struct spdk_spinlock *sspin) 
	memset(sspin, 0, sizeof(*sspin));

	rc = pthread_spin_init(&sspin->spinlock, PTHREAD_PROCESS_PRIVATE);

	SPIN_ASSERT_RETURN_VOID(rc == 0, SPIN_ERR_PTHREAD);

	sspin_init_internal(sspin);

	SSPIN_GET_STACK(sspin, init);

}



void
@@ -2895,6 +2944,8 @@ spdk_spin_destroy(struct spdk_spinlock *sspin) 


	rc = pthread_spin_destroy(&sspin->spinlock);

	SPIN_ASSERT_RETURN_VOID(rc == 0, SPIN_ERR_PTHREAD);



	sspin_fini_internal(sspin);

}



void
@@ -2911,6 +2962,8 @@ spdk_spin_lock(struct spdk_spinlock *sspin) 


	sspin->thread = thread;

	sspin->thread->lock_count++;



	SSPIN_GET_STACK(sspin, lock);

}



void
@@ -2926,6 +2979,8 @@ spdk_spin_unlock(struct spdk_spinlock *sspin) 
	thread->lock_count--;

	sspin->thread = NULL;



	SSPIN_GET_STACK(sspin, unlock);



	rc = pthread_spin_unlock(&sspin->spinlock);

	SPIN_ASSERT_RETURN_VOID(rc == 0, SPIN_ERR_PTHREAD);

}

mk/spdk.common.mk

+1 −1
Original line number Diff line number Diff line
@@ -154,7 +154,7 @@ endif 
SYS_LIBS =



ifeq ($(OS),FreeBSD)

SYS_LIBS += -L/usr/local/lib

SYS_LIBS += -lexecinfo -L/usr/local/lib

COMMON_CFLAGS += -I/usr/local/include

endif