diff options
Diffstat (limited to 'src/pmlogger/src/fetch.c')
| -rw-r--r-- | src/pmlogger/src/fetch.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/src/pmlogger/src/fetch.c b/src/pmlogger/src/fetch.c new file mode 100644 index 0000000..05e0378 --- /dev/null +++ b/src/pmlogger/src/fetch.c @@ -0,0 +1,186 @@ +/* + * Copyright (c) 2013 Red Hat. + * Copyright (c) 1995 Silicon Graphics, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + * + * Thread-safe note + * + * myFetch() returns a PDU buffer that is pinned from _pmGetPDU() or + * __pmEncodeResult() and this needs to be unpinned by the myFetch() + * caller when safe to do so. + */ + +#include "logger.h" + +int +myFetch(int numpmid, pmID pmidlist[], __pmPDU **pdup) +{ + int n = 0; + int ctx; + __pmPDU *pb; + __pmContext *ctxp; + + if (numpmid < 1) + return PM_ERR_TOOSMALL; + + if ((ctx = pmWhichContext()) >= 0) { + ctxp = __pmHandleToPtr(ctx); + if (ctxp == NULL) + return PM_ERR_NOCONTEXT; + if (ctxp->c_type != PM_CONTEXT_HOST) { + PM_UNLOCK(ctxp->c_lock); + return PM_ERR_NOTHOST; + } + } + else + return PM_ERR_NOCONTEXT; + +#if CAN_RECONNECT + if (ctxp->c_pmcd->pc_fd == -1) { + /* lost connection, try to get it back */ + n = reconnect(); + if (n < 0) { + PM_UNLOCK(ctxp->c_lock); + return n; + } + } +#endif + + if (ctxp->c_sent == 0) { + /* + * current profile is _not_ already cached at other end of + * IPC, so send current profile + */ +#ifdef PCP_DEBUG + if (pmDebug & DBG_TRACE_PROFILE) + fprintf(stderr, "myFetch: calling __pmSendProfile, context: %d\n", ctx); +#endif + if ((n = __pmSendProfile(ctxp->c_pmcd->pc_fd, FROM_ANON, ctx, ctxp->c_instprof)) >= 0) + ctxp->c_sent = 1; + } + + if (n >= 0) { + int newcnt; + pmID *newlist = NULL; + int have_dm; + + /* for derived metrics, may need to rewrite the pmidlist */ + have_dm = newcnt = __pmPrepareFetch(ctxp, numpmid, pmidlist, &newlist); + if (newcnt > numpmid) { + /* replace args passed into myFetch */ + numpmid = newcnt; + pmidlist = newlist; + } + + n = __pmSendFetch(ctxp->c_pmcd->pc_fd, FROM_ANON, ctx, &ctxp->c_origin, numpmid, pmidlist); + if (n >= 0){ + int changed = 0; + do { + n = __pmGetPDU(ctxp->c_pmcd->pc_fd, ANY_SIZE, TIMEOUT_DEFAULT, &pb); + /* + * expect PDU_RESULT or + * PDU_ERROR(changed > 0)+PDU_RESULT or + * PDU_ERROR(real error < 0 from PMCD) or + * 0 (end of file) + * < 0 (local error or IPC problem) + * other (bogus PDU) + */ + if (n == PDU_RESULT) { + /* + * Success with a pmResult in a pdubuf. + * + * Need to process derived metrics, if any. + * This is ugly, we need to decode the pdubuf, rebuild + * the pmResult and encode back into a pdubuf ... the + * fastpath of not doing all of this needs to be + * preserved in the common case where derived metrics + * are not being logged. + */ + if (have_dm) { + pmResult *result; + __pmPDU *npb; + int sts; + if ((sts = __pmDecodeResult(pb, &result)) < 0) { + n = sts; + } + else { + __pmFinishResult(ctxp, sts, &result); + if ((sts = __pmEncodeResult(ctxp->c_pmcd->pc_fd, result, &npb)) < 0) + n = sts; + else { + /* using PDU with derived metrics */ + __pmUnpinPDUBuf(pb); + *pdup = npb; + } + } + } + else + *pdup = pb; + } + else if (n == PDU_ERROR) { + __pmDecodeError(pb, &n); + if (n > 0) { + /* PMCD state change protocol */ + changed = n; + n = 0; + } + else { + fprintf(stderr, "myFetch: ERROR PDU: %s\n", pmErrStr(n)); + disconnect(PM_ERR_IPC); + } + __pmUnpinPDUBuf(pb); + } + else if (n == 0) { + fprintf(stderr, "myFetch: End of File: PMCD exited?\n"); + disconnect(PM_ERR_IPC); + } + else if (n < 0) { + fprintf(stderr, "myFetch: __pmGetPDU: Error: %s\n", pmErrStr(n)); + disconnect(PM_ERR_IPC); + } + else { + fprintf(stderr, "myFetch: Unexpected %s PDU from PMCD\n", __pmPDUTypeStr(n)); + disconnect(PM_ERR_IPC); + __pmUnpinPDUBuf(pb); + } + } while (n == 0); + + if (changed & PMCD_ADD_AGENT) { + /* + * PMCD_DROP_AGENT does not matter, no values are returned. + * Trying to restart (PMCD_RESTART_AGENT) is less interesting + * than when we actually start (PMCD_ADD_AGENT) ... the latter + * is also set when a successful restart occurs, but more + * to the point the sequence Install-Remove-Install does + * not involve a restart ... it is the second Install that + * generates the second PMCD_ADD_AGENT that we need to be + * particularly sensitive to, as this may reset counter + * metrics ... + */ + int sts; + if ((sts = putmark()) < 0) { + fprintf(stderr, "putmark: %s\n", pmErrStr(sts)); + exit(1); + } + } + } + if (newlist != NULL) + free(newlist); + } + + if (n < 0 && ctxp->c_pmcd->pc_fd != -1) { + disconnect(n); + } + + PM_UNLOCK(ctxp->c_lock); + return n; +} |