[IA64] another perfmon fix (take2) (a5a70b75) · Commits · 戴 / test

- pfm_context_load(): change return value from EINVAL to EBUSY when context is already loaded. - pfm_check_task_state(): pass test if context state is MASKED. It is safe to give access on PFM_CTX_MASKED because the PMU state (PMD) is stable and saved in software state. This helps multiplexing programs such as the example given in libpfm-3.1. Signed-off-by:

stephane eranian <eranian@hpl.hp.com> Signed-off-by:

Tony Luck <tony.luck@intel.com>

arch/ia64/kernel/perfmon.c

+20 −10

Original line number	Diff line number	Diff line
		@@ -4215,7 +4215,7 @@ pfm_context_load(pfm_context_t ctx, void arg, int count, struct pt_regs *regs)
		DPRINT(("cannot load to [%d], invalid ctx_state=%d\n",
		req->load_pid,
		ctx->ctx_state));
		return -EINVAL;
		return -EBUSY;
		}

		DPRINT(("load_pid [%d] using_dbreg=%d\n", req->load_pid, ctx->ctx_fl_using_dbreg));
		@@ -4716,17 +4716,27 @@ recheck:
		*/
		if (task == current \|\| ctx->ctx_fl_system) return 0;

		/*
		* we are monitoring another thread
		*/
		switch(state) {
		case PFM_CTX_UNLOADED:
		/*
		* if context is UNLOADED we are safe to go
		*/
		if (state == PFM_CTX_UNLOADED) return 0;

		return 0;
		case PFM_CTX_ZOMBIE:
		/*
		* no command can operate on a zombie context
		*/
		if (state == PFM_CTX_ZOMBIE) {
		DPRINT(("cmd %d state zombie cannot operate on context\n", cmd));
		return -EINVAL;
		case PFM_CTX_MASKED:
		/*
		* PMU state has been saved to software even though
		* the thread may still be running.
		*/
		if (cmd != PFM_UNLOAD_CONTEXT) return 0;
		}

		/*

Admin message