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readahead: add interface to sd-daemon.[ch] to control readahead

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This commit is contained in:
Lennart Poettering
2010-09-26 15:50:14 +02:00
parent f0cf061eda
commit 6624768c9c
11 changed files with 405 additions and 18 deletions
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src/notify.c
+29 -13
View File
@@ -36,16 +36,18 @@ static bool arg_ready = false;
static pid_t arg_pid = 0;
static const char *arg_status = NULL;
static bool arg_booted = false;
static const char *arg_readahead = NULL;
static int help(void) {
printf("%s [OPTIONS...] [VARIABLE=VALUE...]\n\n"
"Notify the init system about service status updates.\n\n"
" -h --help Show this help\n"
" --ready Inform the init system about service start-up completion\n"
" --pid[=PID] Set main pid of daemon\n"
" --status=TEXT Set status text\n"
" --booted Returns 0 if the system was booted up with systemd, non-zero otherwise\n",
" -h --help Show this help\n"
" --ready Inform the init system about service start-up completion\n"
" --pid[=PID] Set main pid of daemon\n"
" --status=TEXT Set status text\n"
" --booted Returns 0 if the system was booted up with systemd, non-zero otherwise\n"
" --readahead=ACTION Controls read-ahead operations\n",
program_invocation_short_name);
return 0;
@@ -57,16 +59,18 @@ static int parse_argv(int argc, char *argv[]) {
ARG_READY = 0x100,
ARG_PID,
ARG_STATUS,
ARG_BOOTED
ARG_BOOTED,
ARG_READAHEAD
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "ready", no_argument, NULL, ARG_READY },
{ "pid", optional_argument, NULL, ARG_PID },
{ "status", required_argument, NULL, ARG_STATUS },
{ "booted", no_argument, NULL, ARG_BOOTED },
{ NULL, 0, NULL, 0 }
{ "help", no_argument, NULL, 'h' },
{ "ready", no_argument, NULL, ARG_READY },
{ "pid", optional_argument, NULL, ARG_PID },
{ "status", required_argument, NULL, ARG_STATUS },
{ "booted", no_argument, NULL, ARG_BOOTED },
{ "readahead", required_argument, NULL, ARG_READAHEAD },
{ NULL, 0, NULL, 0 }
};
int c;
@@ -106,6 +110,10 @@ static int parse_argv(int argc, char *argv[]) {
arg_booted = true;
break;
case ARG_READAHEAD:
arg_readahead = optarg;
break;
case '?':
return -EINVAL;
@@ -119,7 +127,8 @@ static int parse_argv(int argc, char *argv[]) {
!arg_ready &&
!arg_status &&
!arg_pid &&
!arg_booted) {
!arg_booted &&
!arg_readahead) {
help();
return -EINVAL;
}
@@ -144,6 +153,13 @@ int main(int argc, char* argv[]) {
if (arg_booted)
return sd_booted() <= 0;
if (arg_readahead) {
if ((r = sd_readahead(arg_readahead)) < 0) {
log_error("Failed to issue read-ahead control command: %s", strerror(-r));
goto finish;
}
}
if (arg_ready)
our_env[i++] = (char*) "READY=1";
src/readahead-collect.c
+68 -5
View File
@@ -41,6 +41,7 @@
#include <sys/ioctl.h>
#include <sys/vfs.h>
#include <getopt.h>
#include <sys/inotify.h>
#include "missing.h"
#include "util.h"
@@ -56,6 +57,7 @@
* - sd_readahead_cancel
* - gzip?
* - remount rw?
* - handle files where nothing is in mincore
* - does ioprio_set work with fadvise()?
*/
@@ -199,12 +201,13 @@ static int qsort_compare(const void *a, const void *b) {
static int collect(const char *root) {
enum {
FD_FANOTIFY,
FD_FANOTIFY, /* Get the actualy fs events */
FD_SIGNAL,
FD_INOTIFY, /* We get notifications to quit early via this fd */
_FD_MAX
};
struct pollfd pollfd[_FD_MAX];
int fanotify_fd = -1, signal_fd = -1, r = 0;
int fanotify_fd = -1, signal_fd = -1, inotify_fd = -1, r = 0;
pid_t my_pid;
Hashmap *files = NULL;
Iterator i;
@@ -251,6 +254,11 @@ static int collect(const char *root) {
goto finish;
}
if ((inotify_fd = open_inotify()) < 0) {
r = inotify_fd;
goto finish;
}
not_after = now(CLOCK_MONOTONIC) + arg_timeout;
my_pid = getpid();
@@ -260,6 +268,8 @@ static int collect(const char *root) {
pollfd[FD_FANOTIFY].events = POLLIN;
pollfd[FD_SIGNAL].fd = signal_fd;
pollfd[FD_SIGNAL].events = POLLIN;
pollfd[FD_INOTIFY].fd = inotify_fd;
pollfd[FD_INOTIFY].events = POLLIN;
sd_notify(0,
"READY=1\n"
@@ -267,6 +277,17 @@ static int collect(const char *root) {
log_debug("Collecting...");
if (access("/dev/.systemd/readahead/cancel", F_OK) >= 0) {
log_debug("Collection canceled");
r = -ECANCELED;
goto finish;
}
if (access("/dev/.systemd/readahead/done", F_OK) >= 0) {
log_debug("Got termination request");
goto done;
}
for (;;) {
union {
struct fanotify_event_metadata metadata;
@@ -298,14 +319,52 @@ static int collect(const char *root) {
goto finish;
}
if (pollfd[FD_SIGNAL].revents != 0)
break;
if (h == 0) {
log_debug("Reached maximum collection time, ending collection.");
break;
}
if (pollfd[FD_SIGNAL].revents) {
log_debug("Got signal.");
break;
}
if (pollfd[FD_INOTIFY].revents) {
uint8_t inotify_buffer[sizeof(struct inotify_event) + FILENAME_MAX];
struct inotify_event *e;
if ((n = read(inotify_fd, &inotify_buffer, sizeof(inotify_buffer))) < 0) {
if (errno == EINTR || errno == EAGAIN)
continue;
log_error("Failed to read inotify event: %m");
r = -errno;
goto finish;
}
e = (struct inotify_event*) inotify_buffer;
while (n > 0) {
size_t step;
if ((e->mask & IN_CREATE) && streq(e->name, "cancel")) {
log_debug("Collection canceled");
r = -ECANCELED;
goto finish;
}
if ((e->mask & IN_CREATE) && streq(e->name, "done")) {
log_debug("Got termination request");
goto done;
}
step = sizeof(struct inotify_event) + e->len;
assert(step <= (size_t) n);
e = (struct inotify_event*) ((uint8_t*) e + step);
n -= step;
}
}
if ((n = read(fanotify_fd, &data, sizeof(data))) < 0) {
if (errno == EINTR || errno == EAGAIN)
@@ -352,6 +411,7 @@ static int collect(const char *root) {
}
}
done:
if (fanotify_fd >= 0) {
close_nointr_nofail(fanotify_fd);
fanotify_fd = -1;
@@ -451,6 +511,9 @@ finish:
if (signal_fd >= 0)
close_nointr_nofail(signal_fd);
if (inotify_fd >= 0)
close_nointr_nofail(inotify_fd);
if (pack) {
fclose(pack);
unlink(pack_fn_new);
src/readahead-common.c
+21
View File
@@ -24,6 +24,7 @@
#include <stdlib.h>
#include <string.h>
#include <sys/sysinfo.h>
#include <sys/inotify.h>
#include "log.h"
#include "readahead-common.h"
@@ -116,3 +117,23 @@ bool enough_ram(void) {
* with at least 128MB
* memory */
}
int open_inotify(void) {
int fd;
if ((fd = inotify_init1(IN_CLOEXEC|IN_NONBLOCK)) < 0) {
log_error("Failed to create inotify handle: %m");
return -errno;
}
mkdir("/dev/.systemd", 0755);
mkdir("/dev/.systemd/readahead", 0755);
if (inotify_add_watch(fd, "/dev/.systemd/readahead", IN_CREATE) < 0) {
log_error("Failed to watch /dev/.systemd/readahead: %m");
close_nointr_nofail(fd);
return -errno;
}
return fd;
}
src/readahead-common.h
+2
View File
@@ -32,4 +32,6 @@ int fs_on_ssd(const char *p);
bool enough_ram(void);
int open_inotify(void);
#endif
src/readahead-replay.c
+43
View File
@@ -33,6 +33,7 @@
#include <sys/stat.h>
#include <unistd.h>
#include <getopt.h>
#include <sys/inotify.h>
#include "missing.h"
#include "util.h"
@@ -119,6 +120,7 @@ static int replay(const char *root) {
char *pack_fn = NULL, c;
bool on_ssd, ready = false;
int prio;
int inotify_fd = -1;
assert(root);
@@ -141,6 +143,11 @@ static int replay(const char *root) {
goto finish;
}
if ((inotify_fd = open_inotify()) < 0) {
r = inotify_fd;
goto finish;
}
if (!(fgets(line, sizeof(line), pack))) {
log_error("Premature end of pack file.");
r = -EIO;
@@ -177,8 +184,40 @@ static int replay(const char *root) {
log_debug("Replaying...");
if (access("/dev/.systemd/readahead/noreplay", F_OK) >= 0) {
log_debug("Got termination request");
goto done;
}
while (!feof(pack) && !ferror(pack)) {
uint8_t inotify_buffer[sizeof(struct inotify_event) + FILENAME_MAX];
int k;
ssize_t n;
if ((n = read(inotify_fd, &inotify_buffer, sizeof(inotify_buffer))) < 0) {
if (errno != EINTR && errno != EAGAIN) {
log_error("Failed to read inotify event: %m");
r = -errno;
goto finish;
}
} else {
struct inotify_event *e = (struct inotify_event*) inotify_buffer;
while (n > 0) {
size_t step;
if ((e->mask & IN_CREATE) && streq(e->name, "noreplay")) {
log_debug("Got termination request");
goto done;
}
step = sizeof(struct inotify_event) + e->len;
assert(step <= (size_t) n);
e = (struct inotify_event*) ((uint8_t*) e + step);
n -= step;
}
}
if ((k = unpack_file(pack)) < 0) {
r = k;
@@ -193,6 +232,7 @@ static int replay(const char *root) {
}
}
done:
if (!ready)
sd_notify(0, "READY=1");
@@ -208,6 +248,9 @@ finish:
if (pack)
fclose(pack);
if (inotify_fd >= 0)
close_nointr_nofail(inotify_fd);
free(pack_fn);
return r;
src/sd-daemon.c
+38
View File
@@ -433,3 +433,41 @@ int sd_booted(void) {
return a.st_dev != b.st_dev;
#endif
}
static int touch(const char *path) {
#if !defined(DISABLE_SYSTEMD) && defined(__linux__)
int fd;
mkdir("/dev/.systemd", 0755);
mkdir("/dev/.systemd/readahead", 0755);
if ((fd = open(path, O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY, 0666)) < 0)
return -errno;
for (;;) {
if (close(fd) >= 0)
break;
if (errno != -EINTR)
return -errno;
}
#endif
return 0;
}
int sd_readahead(const char *action) {
if (!action)
return -EINVAL;
if (strcmp(action, "cancel") == 0)
return touch("/dev/.systemd/readahead/cancel");
else if (strcmp(action, "done") == 0)
return touch("/dev/.systemd/readahead/done");
else if (strcmp(action, "noreplay") == 0)
return touch("/dev/.systemd/readahead/noreplay");
return -EINVAL;
}
src/sd-daemon.h
+10
View File
@@ -254,6 +254,16 @@ int sd_notifyf(int unset_environment, const char *format, ...) _sd_printf_attr_(
*/
int sd_booted(void) _sd_hidden_;
/*
Controls ongoing disk read-ahead operations during boot-up. The argument
must be a string, and either "cancel", "done" or "noreplay".
cancel = terminate read-ahead data collection, drop collected information
done = terminate read-ahead data collection, keep collected information
noreplay = terminate read-ahead replay
*/
int sd_readahead(const char *action);
#ifdef __cplusplus
}
#endif