random: add tracepoints for easier debugging and verification (00ce1db1) · Commits · e / devices / android_kernel_teracube_emerald

drivers/char/random.c

+22 −4

Original line number	Diff line number	Diff line
		@@ -266,6 +266,9 @@
		#include <asm/irq_regs.h>
		#include <asm/io.h>

		#define CREATE_TRACE_POINTS
		#include <trace/events/random.h>

		/*
		* Configuration information
		*/
		@@ -478,7 +481,7 @@ static __u32 const twist_table[8] = {
		* it's cheap to do so and helps slightly in the expected case where
		* the entropy is concentrated in the low-order bits.
		*/
		static void __mix_pool_bytes(struct entropy_store r, const void in,
		static void _mix_pool_bytes(struct entropy_store r, const void in,
		int nbytes, __u8 out[64])
		{
		unsigned long i, j, tap1, tap2, tap3, tap4, tap5;
		@@ -531,13 +534,21 @@ static void __mix_pool_bytes(struct entropy_store r, const void in,
		((__u32 *)out)[j] = r->pool[(i - j) & wordmask];
		}

		static void __mix_pool_bytes(struct entropy_store r, const void in,
		int nbytes, __u8 out[64])
		{
		trace_mix_pool_bytes_nolock(r->name, nbytes, _RET_IP_);
		_mix_pool_bytes(r, in, nbytes, out);
		}

		static void mix_pool_bytes(struct entropy_store r, const void in,
		int nbytes, __u8 out[64])
		{
		unsigned long flags;

		trace_mix_pool_bytes(r->name, nbytes, _RET_IP_);
		spin_lock_irqsave(&r->lock, flags);
		__mix_pool_bytes(r, in, nbytes, out);
		_mix_pool_bytes(r, in, nbytes, out);
		spin_unlock_irqrestore(&r->lock, flags);
		}

		@@ -585,6 +596,7 @@ static void credit_entropy_bits(struct entropy_store *r, int nbits)
		retry:
		entropy_count = orig = ACCESS_ONCE(r->entropy_count);
		entropy_count += nbits;

		if (entropy_count < 0) {
		DEBUG_ENT("negative entropy/overflow\n");
		entropy_count = 0;
		@@ -599,6 +611,9 @@ static void credit_entropy_bits(struct entropy_store *r, int nbits)
		r->initialized = 1;
		}

		trace_credit_entropy_bits(r->name, nbits, entropy_count,
		r->entropy_total, _RET_IP_);

		/* should we wake readers? */
		if (r == &input_pool && entropy_count >= random_read_wakeup_thresh) {
		wake_up_interruptible(&random_read_wait);
		@@ -971,6 +986,7 @@ static ssize_t extract_entropy(struct entropy_store r, void buf,
		ssize_t ret = 0, i;
		__u8 tmp[EXTRACT_SIZE];

		trace_extract_entropy(r->name, nbytes, r->entropy_count, _RET_IP_);
		xfer_secondary_pool(r, nbytes);
		nbytes = account(r, nbytes, min, reserved);

		@@ -1005,6 +1021,7 @@ static ssize_t extract_entropy_user(struct entropy_store r, void __user buf,
		ssize_t ret = 0, i;
		__u8 tmp[EXTRACT_SIZE];

		trace_extract_entropy_user(r->name, nbytes, r->entropy_count, _RET_IP_);
		xfer_secondary_pool(r, nbytes);
		nbytes = account(r, nbytes, 0, 0);

		@@ -1062,6 +1079,7 @@ void get_random_bytes_arch(void *buf, int nbytes)
		{
		char *p = buf;

		trace_get_random_bytes(nbytes, _RET_IP_);
		while (nbytes) {
		unsigned long v;
		int chunk = min(nbytes, (int)sizeof(unsigned long));

include/trace/events/random.h

0 → 100644

+134 −0

Original line number	Diff line number	Diff line
		#undef TRACE_SYSTEM
		#define TRACE_SYSTEM random

		#if !defined(_TRACE_RANDOM_H) \|\| defined(TRACE_HEADER_MULTI_READ)
		#define _TRACE_RANDOM_H

		#include <linux/writeback.h>
		#include <linux/tracepoint.h>

		DECLARE_EVENT_CLASS(random__mix_pool_bytes,
		TP_PROTO(const char *pool_name, int bytes, unsigned long IP),

		TP_ARGS(pool_name, bytes, IP),

		TP_STRUCT__entry(
		__field( const char *, pool_name )
		__field( int, bytes )
		__field(unsigned long, IP )
		),

		TP_fast_assign(
		__entry->pool_name = pool_name;
		__entry->bytes = bytes;
		__entry->IP = IP;
		),

		TP_printk("%s pool: bytes %d caller %pF",
		__entry->pool_name, __entry->bytes, (void *)__entry->IP)
		);

		DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes,
		TP_PROTO(const char *pool_name, int bytes, unsigned long IP),

		TP_ARGS(pool_name, bytes, IP)
		);

		DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes_nolock,
		TP_PROTO(const char *pool_name, int bytes, unsigned long IP),

		TP_ARGS(pool_name, bytes, IP)
		);

		TRACE_EVENT(credit_entropy_bits,
		TP_PROTO(const char *pool_name, int bits, int entropy_count,
		int entropy_total, unsigned long IP),

		TP_ARGS(pool_name, bits, entropy_count, entropy_total, IP),

		TP_STRUCT__entry(
		__field( const char *, pool_name )
		__field( int, bits )
		__field( int, entropy_count )
		__field( int, entropy_total )
		__field(unsigned long, IP )
		),

		TP_fast_assign(
		__entry->pool_name = pool_name;
		__entry->bits = bits;
		__entry->entropy_count = entropy_count;
		__entry->entropy_total = entropy_total;
		__entry->IP = IP;
		),

		TP_printk("%s pool: bits %d entropy_count %d entropy_total %d "
		"caller %pF", __entry->pool_name, __entry->bits,
		__entry->entropy_count, __entry->entropy_total,
		(void *)__entry->IP)
		);

		TRACE_EVENT(get_random_bytes,
		TP_PROTO(int nbytes, unsigned long IP),

		TP_ARGS(nbytes, IP),

		TP_STRUCT__entry(
		__field( int, nbytes )
		__field(unsigned long, IP )
		),

		TP_fast_assign(
		__entry->nbytes = nbytes;
		__entry->IP = IP;
		),

		TP_printk("nbytes %d caller %pF", __entry->nbytes, (void *)__entry->IP)
		);

		DECLARE_EVENT_CLASS(random__extract_entropy,
		TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
		unsigned long IP),

		TP_ARGS(pool_name, nbytes, entropy_count, IP),

		TP_STRUCT__entry(
		__field( const char *, pool_name )
		__field( int, nbytes )
		__field( int, entropy_count )
		__field(unsigned long, IP )
		),

		TP_fast_assign(
		__entry->pool_name = pool_name;
		__entry->nbytes = nbytes;
		__entry->entropy_count = entropy_count;
		__entry->IP = IP;
		),

		TP_printk("%s pool: nbytes %d entropy_count %d caller %pF",
		__entry->pool_name, __entry->nbytes, __entry->entropy_count,
		(void *)__entry->IP)
		);


		DEFINE_EVENT(random__extract_entropy, extract_entropy,
		TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
		unsigned long IP),

		TP_ARGS(pool_name, nbytes, entropy_count, IP)
		);

		DEFINE_EVENT(random__extract_entropy, extract_entropy_user,
		TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
		unsigned long IP),

		TP_ARGS(pool_name, nbytes, entropy_count, IP)
		);



		#endif /* _TRACE_RANDOM_H */

		/* This part must be outside protection */
		#include <trace/define_trace.h>