diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h index 3691e0e76a1a..9ec229dfddaa 100644 --- a/include/linux/trace_seq.h +++ b/include/linux/trace_seq.h @@ -8,11 +8,14 @@ /* * Trace sequences are used to allow a function to call several other functions - * to create a string of data to use (up to a max of PAGE_SIZE). + * to create a string of data to use. */ +#define TRACE_SEQ_BUFFER_SIZE (PAGE_SIZE * 2 - \ + (sizeof(struct seq_buf) + sizeof(size_t) + sizeof(int))) + struct trace_seq { - char buffer[PAGE_SIZE]; + char buffer[TRACE_SEQ_BUFFER_SIZE]; struct seq_buf seq; size_t readpos; int full; @@ -21,7 +24,7 @@ struct trace_seq { static inline void trace_seq_init(struct trace_seq *s) { - seq_buf_init(&s->seq, s->buffer, PAGE_SIZE); + seq_buf_init(&s->seq, s->buffer, TRACE_SEQ_BUFFER_SIZE); s->full = 0; s->readpos = 0; } diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index dba1328e454b..0be30cccabb4 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3753,7 +3753,7 @@ static bool trace_safe_str(struct trace_iterator *iter, const char *str, /* OK if part of the temp seq buffer */ if ((addr >= (unsigned long)iter->tmp_seq.buffer) && - (addr < (unsigned long)iter->tmp_seq.buffer + PAGE_SIZE)) + (addr < (unsigned long)iter->tmp_seq.buffer + TRACE_SEQ_BUFFER_SIZE)) return true; /* Core rodata can not be freed */ @@ -6932,8 +6932,8 @@ waitagain: goto out; } - if (cnt >= PAGE_SIZE) - cnt = PAGE_SIZE - 1; + if (cnt >= TRACE_SEQ_BUFFER_SIZE) + cnt = TRACE_SEQ_BUFFER_SIZE - 1; /* reset all but tr, trace, and overruns */ trace_iterator_reset(iter); diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c index 7be97229ddf8..c158d65a8a88 100644 --- a/kernel/trace/trace_seq.c +++ b/kernel/trace/trace_seq.c @@ -13,9 +13,6 @@ * trace_seq_init() more than once to reset the trace_seq to start * from scratch. * - * The buffer size is currently PAGE_SIZE, although it may become dynamic - * in the future. - * * A write to the buffer will either succeed or fail. That is, unlike * sprintf() there will not be a partial write (well it may write into * the buffer but it wont update the pointers). This allows users to