| Message ID | 20180830150900.27412-1-tz.stoyanov@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Introduce new libtracevent API: tep_override_comm() | expand |
On Thu, 30 Aug 2018 18:09:00 +0300 "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> wrote: > Added a new API of tracevent library: tep_override_comm() > It registers a pid / comm mapping. If a mapping with the same > pid already exists, the entry is updated with the new comm. > > Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com> > --- > include/traceevent/event-parse.h | 1 + > lib/traceevent/event-parse.c | 67 +++++++++++++++++++++++++------- > 2 files changed, 53 insertions(+), 15 deletions(-) > > diff --git a/include/traceevent/event-parse.h b/include/traceevent/event-parse.h > index 713a4e4..0dcc024 100644 > --- a/include/traceevent/event-parse.h > +++ b/include/traceevent/event-parse.h > @@ -607,6 +607,7 @@ int tep_set_function_resolver(struct tep_handle *pevent, > tep_func_resolver_t *func, void *priv); > void tep_reset_function_resolver(struct tep_handle *pevent); > int tep_register_comm(struct tep_handle *pevent, const char *comm, int pid); > +int tep_override_comm(struct tep_handle *pevent, const char *comm, int pid); > int tep_register_trace_clock(struct tep_handle *pevent, const char *trace_clock); > int tep_register_function(struct tep_handle *pevent, char *name, > unsigned long long addr, char *mod); > diff --git a/lib/traceevent/event-parse.c b/lib/traceevent/event-parse.c > index ce1e202..e40f63c 100644 > --- a/lib/traceevent/event-parse.c > +++ b/lib/traceevent/event-parse.c > @@ -230,10 +230,11 @@ int tep_pid_is_registered(struct tep_handle *pevent, int pid) > * we must add this pid. This is much slower than when cmdlines > * are added before the array is initialized. > */ > -static int add_new_comm(struct tep_handle *pevent, const char *comm, int pid) > +static int add_new_comm(struct tep_handle *pevent, > + const char *comm, int pid, int overrite) Typo, should be "overwrite" or "override". Also make it a "bool" type. > { > struct cmdline *cmdlines = pevent->cmdlines; > - const struct cmdline *cmdline; > + struct cmdline *cmdline; > struct cmdline key; > > if (!pid) > @@ -245,8 +246,18 @@ static int add_new_comm(struct tep_handle *pevent, const char *comm, int pid) > cmdline = bsearch(&key, pevent->cmdlines, pevent->cmdline_count, > sizeof(*pevent->cmdlines), cmdline_cmp); > if (cmdline) { > - errno = EEXIST; > - return -1; > + if (!overrite) { > + errno = EEXIST; > + return -1; > + } > + if (cmdline->comm) > + free(cmdline->comm); > + cmdline->comm = strdup(comm); We don't want to lose the old comm if the new comm fails to be allocated. Thus, use a temp variable to save the strdup(). char *new_comm; new_comm = strdup(comm); if (!new_comm) { errno = ENOMEM; return -1; } free(cmdline->comm); cmdline->comm = new_comm; > + if(!cmdline->comm) { > + errno = ENOMEM; > + return -1; > + } > + return 0; > } > > cmdlines = realloc(cmdlines, sizeof(*cmdlines) * (pevent->cmdline_count + 1)); > @@ -273,21 +284,13 @@ static int add_new_comm(struct tep_handle *pevent, const char *comm, int pid) > return 0; > } > > -/** > - * tep_register_comm - register a pid / comm mapping > - * @pevent: handle for the pevent > - * @comm: the command line to register > - * @pid: the pid to map the command line to > - * > - * This adds a mapping to search for command line names with > - * a given pid. The comm is duplicated. > - */ > -int tep_register_comm(struct tep_handle *pevent, const char *comm, int pid) > +static int _tep_register_comm(struct tep_handle *pevent, > + const char *comm, int pid, int overrite) Same comment here for "overrite". > { > struct cmdline_list *item; > > if (pevent->cmdlines) > - return add_new_comm(pevent, comm, pid); > + return add_new_comm(pevent, comm, pid, overrite); > > item = malloc(sizeof(*item)); > if (!item) > @@ -310,6 +313,40 @@ int tep_register_comm(struct tep_handle *pevent, const char *comm, int pid) > return 0; > } > > +/** > + * tep_register_comm - register a pid / comm mapping > + * @pevent: handle for the pevent > + * @comm: the command line to register > + * @pid: the pid to map the command line to > + * > + * This adds a mapping to search for command line names with > + * a given pid. The comm is duplicated. If a command with the same pid > + * already exist, -1 is returned and errno is set to EEXIST > + */ > +int tep_register_comm(struct tep_handle *pevent, const char *comm, int pid) > +{ > + return _tep_register_comm(pevent, comm, pid, 0); Pass in "false" instead of 0. > +} > + > +/** > + * tep_override_comm - register a pid / comm mapping > + * @pevent: handle for the pevent > + * @comm: the command line to register > + * @pid: the pid to map the command line to > + * > + * This adds a mapping to search for command line names with > + * a given pid. The comm is duplicated. If a command with the same pid > + * already exist, the command string is udapted with the new one > + */ > +int tep_override_comm(struct tep_handle *pevent, const char *comm, int pid) > +{ > + if (!pevent->cmdlines && cmdline_init(pevent)) { > + errno = ENOMEM; > + return -1; > + } > + return _tep_register_comm(pevent, comm, pid, 1); Pass in "true" instead of 1. > +} > + Rest looks good. Thanks Tzvetomir! -- Steve > int tep_register_trace_clock(struct tep_handle *pevent, const char *trace_clock) > { > pevent->trace_clock = strdup(trace_clock);
diff --git a/include/traceevent/event-parse.h b/include/traceevent/event-parse.h index 713a4e4..0dcc024 100644 --- a/include/traceevent/event-parse.h +++ b/include/traceevent/event-parse.h @@ -607,6 +607,7 @@ int tep_set_function_resolver(struct tep_handle *pevent, tep_func_resolver_t *func, void *priv); void tep_reset_function_resolver(struct tep_handle *pevent); int tep_register_comm(struct tep_handle *pevent, const char *comm, int pid); +int tep_override_comm(struct tep_handle *pevent, const char *comm, int pid); int tep_register_trace_clock(struct tep_handle *pevent, const char *trace_clock); int tep_register_function(struct tep_handle *pevent, char *name, unsigned long long addr, char *mod); diff --git a/lib/traceevent/event-parse.c b/lib/traceevent/event-parse.c index ce1e202..e40f63c 100644 --- a/lib/traceevent/event-parse.c +++ b/lib/traceevent/event-parse.c @@ -230,10 +230,11 @@ int tep_pid_is_registered(struct tep_handle *pevent, int pid) * we must add this pid. This is much slower than when cmdlines * are added before the array is initialized. */ -static int add_new_comm(struct tep_handle *pevent, const char *comm, int pid) +static int add_new_comm(struct tep_handle *pevent, + const char *comm, int pid, int overrite) { struct cmdline *cmdlines = pevent->cmdlines; - const struct cmdline *cmdline; + struct cmdline *cmdline; struct cmdline key; if (!pid) @@ -245,8 +246,18 @@ static int add_new_comm(struct tep_handle *pevent, const char *comm, int pid) cmdline = bsearch(&key, pevent->cmdlines, pevent->cmdline_count, sizeof(*pevent->cmdlines), cmdline_cmp); if (cmdline) { - errno = EEXIST; - return -1; + if (!overrite) { + errno = EEXIST; + return -1; + } + if (cmdline->comm) + free(cmdline->comm); + cmdline->comm = strdup(comm); + if(!cmdline->comm) { + errno = ENOMEM; + return -1; + } + return 0; } cmdlines = realloc(cmdlines, sizeof(*cmdlines) * (pevent->cmdline_count + 1)); @@ -273,21 +284,13 @@ static int add_new_comm(struct tep_handle *pevent, const char *comm, int pid) return 0; } -/** - * tep_register_comm - register a pid / comm mapping - * @pevent: handle for the pevent - * @comm: the command line to register - * @pid: the pid to map the command line to - * - * This adds a mapping to search for command line names with - * a given pid. The comm is duplicated. - */ -int tep_register_comm(struct tep_handle *pevent, const char *comm, int pid) +static int _tep_register_comm(struct tep_handle *pevent, + const char *comm, int pid, int overrite) { struct cmdline_list *item; if (pevent->cmdlines) - return add_new_comm(pevent, comm, pid); + return add_new_comm(pevent, comm, pid, overrite); item = malloc(sizeof(*item)); if (!item) @@ -310,6 +313,40 @@ int tep_register_comm(struct tep_handle *pevent, const char *comm, int pid) return 0; } +/** + * tep_register_comm - register a pid / comm mapping + * @pevent: handle for the pevent + * @comm: the command line to register + * @pid: the pid to map the command line to + * + * This adds a mapping to search for command line names with + * a given pid. The comm is duplicated. If a command with the same pid + * already exist, -1 is returned and errno is set to EEXIST + */ +int tep_register_comm(struct tep_handle *pevent, const char *comm, int pid) +{ + return _tep_register_comm(pevent, comm, pid, 0); +} + +/** + * tep_override_comm - register a pid / comm mapping + * @pevent: handle for the pevent + * @comm: the command line to register + * @pid: the pid to map the command line to + * + * This adds a mapping to search for command line names with + * a given pid. The comm is duplicated. If a command with the same pid + * already exist, the command string is udapted with the new one + */ +int tep_override_comm(struct tep_handle *pevent, const char *comm, int pid) +{ + if (!pevent->cmdlines && cmdline_init(pevent)) { + errno = ENOMEM; + return -1; + } + return _tep_register_comm(pevent, comm, pid, 1); +} + int tep_register_trace_clock(struct tep_handle *pevent, const char *trace_clock) { pevent->trace_clock = strdup(trace_clock);
Added a new API of tracevent library: tep_override_comm() It registers a pid / comm mapping. If a mapping with the same pid already exists, the entry is updated with the new comm. Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com> --- include/traceevent/event-parse.h | 1 + lib/traceevent/event-parse.c | 67 +++++++++++++++++++++++++------- 2 files changed, 53 insertions(+), 15 deletions(-)