Commit 7acc2d90 authored by Paul E. McKenney's avatar Paul E. McKenney Committed by Boqun Feng
Browse files

rcutorture: Make cur_ops->format_gp_seqs take buffer length 



The Tree and Tiny implementations of rcutorture_format_gp_seqs() use
hard-coded constants for the length of the buffer that they format into.
This is of course an accident waiting to happen, so this commit therefore
makes them take a length argument.  The rcutorture calling code uses
ARRAY_SIZE() to safely compute this new argument.

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
Signed-off-by: default avatarBoqun Feng <boqun.feng@gmail.com>
parent 65e6ff0f

kernel/rcu/rcu.h

+1 −1
Original line number Diff line number Diff line
@@ -591,7 +591,7 @@ void do_trace_rcu_torture_read(const char *rcutorturename, 
static inline void rcu_gp_set_torture_wait(int duration) { }

#endif

unsigned long long rcutorture_gather_gp_seqs(void);

void rcutorture_format_gp_seqs(unsigned long long seqs, char *cp);

void rcutorture_format_gp_seqs(unsigned long long seqs, char *cp, size_t len);



#ifdef CONFIG_TINY_SRCU

kernel/rcu/rcutorture.c

+5 −3
Original line number Diff line number Diff line
@@ -411,7 +411,7 @@ struct rcu_torture_ops { 
	void (*gp_slow_unregister)(atomic_t *rgssp);

	bool (*reader_blocked)(void);

	unsigned long long (*gather_gp_seqs)(void);

	void (*format_gp_seqs)(unsigned long long seqs, char *cp);

	void (*format_gp_seqs)(unsigned long long seqs, char *cp, size_t len);

	long cbflood_max;

	int irq_capable;

	int can_boost;
@@ -3688,8 +3688,10 @@ rcu_torture_cleanup(void) 
				char buf2[20+1];

				char sepchar = '-';



				cur_ops->format_gp_seqs(err_segs[i].rt_gp_seq, buf1);

				cur_ops->format_gp_seqs(err_segs[i].rt_gp_seq_end, buf2);

				cur_ops->format_gp_seqs(err_segs[i].rt_gp_seq,

							buf1, ARRAY_SIZE(buf1));

				cur_ops->format_gp_seqs(err_segs[i].rt_gp_seq_end,

							buf2, ARRAY_SIZE(buf2));

				if (err_segs[i].rt_gp_seq == err_segs[i].rt_gp_seq_end) {

					if (buf2[0]) {

						for (j = 0; buf2[j]; j++)

kernel/rcu/tiny.c

+2 −2
Original line number Diff line number Diff line
@@ -264,9 +264,9 @@ unsigned long long rcutorture_gather_gp_seqs(void) 
}

EXPORT_SYMBOL_GPL(rcutorture_gather_gp_seqs);



void rcutorture_format_gp_seqs(unsigned long long seqs, char *cp)

void rcutorture_format_gp_seqs(unsigned long long seqs, char *cp, size_t len)

{

	snprintf(cp, 8, "g%04llx", seqs & 0xffffULL);

	snprintf(cp, len, "g%04llx", seqs & 0xffffULL);

}

EXPORT_SYMBOL_GPL(rcutorture_format_gp_seqs);

#endif

kernel/rcu/tree.c

+2 −2
Original line number Diff line number Diff line
@@ -548,13 +548,13 @@ unsigned long long rcutorture_gather_gp_seqs(void) 
EXPORT_SYMBOL_GPL(rcutorture_gather_gp_seqs);



/* Format grace-period sequence numbers for rcutorture diagnostics. */

void rcutorture_format_gp_seqs(unsigned long long seqs, char *cp)

void rcutorture_format_gp_seqs(unsigned long long seqs, char *cp, size_t len)

{

	unsigned int egp = (seqs >> 16) & 0xffffffULL;

	unsigned int ggp = (seqs >> 40) & 0xffffULL;

	unsigned int pgp = seqs & 0xffffULL;



	snprintf(cp, 20, "g%04x:e%06x:p%04x", ggp, egp, pgp);

	snprintf(cp, len, "g%04x:e%06x:p%04x", ggp, egp, pgp);

}

EXPORT_SYMBOL_GPL(rcutorture_format_gp_seqs);