Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2565711f authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

perf: Improve the perf_sample_data struct layout 



This patch reorders fields in the perf_sample_data struct in order to
minimize the number of cachelines touched in perf_sample_data_init().
It also removes some intializations which are redundant with the code
in kernel/events/core.c

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1411559322-16548-7-git-send-email-eranian@google.com


Cc: cebbert.lkml@gmail.com
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: jolsa@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 4b6c5177

include/linux/perf_event.h

+17 −17
Original line number Original line Diff line number Diff line
@@ -580,35 +580,40 @@ extern u64 perf_event_read_value(struct perf_event *event, 








struct perf_sample_data {

struct perf_sample_data {

	u64				type;

	/*

	 * Fields set by perf_sample_data_init(), group so as to

	 * minimize the cachelines touched.

	 */

	u64				addr;

	struct perf_raw_record		*raw;

	struct perf_branch_stack	*br_stack;

	u64				period;

	u64				weight;

	u64				txn;

	union  perf_mem_data_src	data_src;





	/*

	 * The other fields, optionally {set,used} by

	 * perf_{prepare,output}_sample().

	 */

	u64				type;

	u64				ip;

	u64				ip;

	struct {

	struct {

		u32	pid;

		u32	pid;

		u32	tid;

		u32	tid;

	}				tid_entry;

	}				tid_entry;

	u64				time;

	u64				time;

	u64				addr;

	u64				id;

	u64				id;

	u64				stream_id;

	u64				stream_id;

	struct {

	struct {

		u32	cpu;

		u32	cpu;

		u32	reserved;

		u32	reserved;

	}				cpu_entry;

	}				cpu_entry;

	u64				period;

	union  perf_mem_data_src	data_src;

	struct perf_callchain_entry	*callchain;

	struct perf_callchain_entry	*callchain;

	struct perf_raw_record		*raw;

	struct perf_branch_stack	*br_stack;

	struct perf_regs		regs_user;

	struct perf_regs		regs_user;

	struct perf_regs		regs_intr;

	struct perf_regs		regs_intr;

	u64				stack_user_size;

	u64				stack_user_size;

	u64				weight;

} ____cacheline_aligned;

	/*

	 * Transaction flags for abort events:

	 */

	u64				txn;

};





/* default value for data source */

/* default value for data source */

#define PERF_MEM_NA (PERF_MEM_S(OP, NA)   |\

#define PERF_MEM_NA (PERF_MEM_S(OP, NA)   |\
@@ -625,14 +630,9 @@ static inline void perf_sample_data_init(struct perf_sample_data *data, 
	data->raw  = NULL;

	data->raw  = NULL;

	data->br_stack = NULL;

	data->br_stack = NULL;

	data->period = period;

	data->period = period;

	data->regs_user.abi = PERF_SAMPLE_REGS_ABI_NONE;

	data->regs_user.regs = NULL;

	data->stack_user_size = 0;

	data->weight = 0;

	data->weight = 0;

	data->data_src.val = PERF_MEM_NA;

	data->data_src.val = PERF_MEM_NA;

	data->txn = 0;

	data->txn = 0;

	data->regs_intr.abi = PERF_SAMPLE_REGS_ABI_NONE;

	data->regs_intr.regs = NULL;

}

}





extern void perf_output_sample(struct perf_output_handle *handle,

extern void perf_output_sample(struct perf_output_handle *handle,

kernel/events/core.c

+8 −8
Original line number Original line Diff line number Diff line
@@ -4471,8 +4471,11 @@ static void perf_sample_regs_user(struct perf_regs *regs_user, 
	}

	}





	if (regs) {

	if (regs) {

		regs_user->regs = regs;

		regs_user->abi  = perf_reg_abi(current);

		regs_user->abi  = perf_reg_abi(current);

		regs_user->regs = regs;

	} else {

		regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE;

		regs_user->regs = NULL;

	}

	}

}

}
@@ -4947,12 +4950,13 @@ void perf_prepare_sample(struct perf_event_header *header, 
		header->size += size;

		header->size += size;

	}

	}





	if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER))

		perf_sample_regs_user(&data->regs_user, regs);



	if (sample_type & PERF_SAMPLE_REGS_USER) {

	if (sample_type & PERF_SAMPLE_REGS_USER) {

		/* regs dump ABI info */

		/* regs dump ABI info */

		int size = sizeof(u64);

		int size = sizeof(u64);





		perf_sample_regs_user(&data->regs_user, regs);



		if (data->regs_user.regs) {

		if (data->regs_user.regs) {

			u64 mask = event->attr.sample_regs_user;

			u64 mask = event->attr.sample_regs_user;

			size += hweight64(mask) * sizeof(u64);

			size += hweight64(mask) * sizeof(u64);
@@ -4968,15 +4972,11 @@ void perf_prepare_sample(struct perf_event_header *header, 
		 * in case new sample type is added, because we could eat

		 * in case new sample type is added, because we could eat

		 * up the rest of the sample size.

		 * up the rest of the sample size.

		 */

		 */

		struct perf_regs *uregs = &data->regs_user;

		u16 stack_size = event->attr.sample_stack_user;

		u16 stack_size = event->attr.sample_stack_user;

		u16 size = sizeof(u64);

		u16 size = sizeof(u64);





		if (!uregs->abi)

			perf_sample_regs_user(uregs, regs);



		stack_size = perf_sample_ustack_size(stack_size, header->size,

		stack_size = perf_sample_ustack_size(stack_size, header->size,

						     uregs->regs);

						     data->regs_user.regs);





		/*

		/*

		 * If there is something to dump, add space for the dump

		 * If there is something to dump, add space for the dump