Commit-ID: 41033a18aa027a1260c2546c02a1b185e92e6cf5 Gitweb: http://git.kernel.org/tip/41033a18aa027a1260c2546c02a1b185e92e6cf5 Author: Eduard - Gabriel Munteanu <eduard.munteanu@xxxxxxxxxxx> AuthorDate: Mon, 23 Mar 2009 15:12:22 +0200 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Mon, 23 Mar 2009 16:06:54 +0100 tracing: provide trace_seq_reserve() trace_seq_reserve() allows a caller to reserve space in a trace_seq and write directly into it. This makes it easier to export binary data to userspace via the tracing interface, by simply filling in a struct. Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@xxxxxxxxxxx> LKML-Reference: <6698c7b983cc20ec84becc757362f48a8948762d.1237813499.git.eduard.munteanu@xxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- kernel/trace/trace_output.c | 13 +++++++++++++ kernel/trace/trace_output.h | 1 + 2 files changed, 14 insertions(+), 0 deletions(-) diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 19261fd..6595074 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -167,6 +167,19 @@ int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len) return trace_seq_putmem(s, hex, j); } +void *trace_seq_reserve(struct trace_seq *s, size_t len) +{ + void *ret; + + if (len > ((PAGE_SIZE - 1) - s->len)) + return NULL; + + ret = s->buffer + s->len; + s->len += len; + + return ret; +} + int trace_seq_path(struct trace_seq *s, struct path *path) { unsigned char *p; diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h index 35c422f..0ae20b8 100644 --- a/kernel/trace/trace_output.h +++ b/kernel/trace/trace_output.h @@ -33,6 +33,7 @@ int trace_seq_puts(struct trace_seq *s, const char *str); int trace_seq_putc(struct trace_seq *s, unsigned char c); int trace_seq_putmem(struct trace_seq *s, void *mem, size_t len); int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len); +void *trace_seq_reserve(struct trace_seq *s, size_t len); int trace_seq_path(struct trace_seq *s, struct path *path); int seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s, unsigned long sym_flags); -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html